where does the process of translation occur in a bacterial cell
in the cytoplasm
1906423
Translation (biology) In molecular biology and genetics, translation is the process in which ribosomes in the cytoplasm or ER synthesize proteins after the process of transcription of DNA to RNA in the cell's nucleus. The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in a ribosome to produce a specific amino acid chain, or polypeptide. The polypeptide later folds into an active protein and performs its functions in the cell. The ribosome facilitates decoding by inducing the binding of complementary tRNA anticodon sequences to mRNA codons. The tRNAs carry specific amino acids that are chained
Translation (biology)
9850035
until the next one is reached. This phenomenon is known as antitermination and is utilised by certain bacteriophages. Bacterial transcription Bacterial transcription is the process in which messenger RNA transcripts of genetic material in bacteria are produced, to be translated for the production of proteins. Unlike in eukaryotes, bacterial transcription and translation can occur simultaneously in the cytoplasm. This is impossible in eukaryotes, where transcription occurs in a membrane-bound nucleus while translation occurs outside the nucleus in the cytoplasm (see also Eukaryotic transcription). In bacteria genetic material is not enclosed in a membrane-enclosed nucleus and has access to ribosomes in
Bacterial transcription
9850032
Bacterial transcription Bacterial transcription is the process in which messenger RNA transcripts of genetic material in bacteria are produced, to be translated for the production of proteins. Unlike in eukaryotes, bacterial transcription and translation can occur simultaneously in the cytoplasm. This is impossible in eukaryotes, where transcription occurs in a membrane-bound nucleus while translation occurs outside the nucleus in the cytoplasm (see also Eukaryotic transcription). In bacteria genetic material is not enclosed in a membrane-enclosed nucleus and has access to ribosomes in the cytoplasm. Transcription is carried out by RNA polymerase but its specificity is controlled by sequence-specific DNA binding
Bacterial transcription
19530414
cell as the capsid is kept outside the cell. Biosynthesis After the bacterial DNA is inserted into the cell, the process of biosynthesis is initiated. Biosynthesis involves the utilization of the host cells' nucleotides and enzymes to make copies of the phage DNA. The mRNA in the cytoplasm are transcribed from the phage DNA being involved in the biosynthesis of phage enzymes and capsids proteins. Therefore, the ribosomes, enzymes, and amino acids of the host are involved in translation. Maturation Maturation is submitted by the assembly of bacteriophage DNA and capsids into virions. Late proteins are important in assembly. Assembly
T-even bacteriophages
9564122
components of the cytoplasm within the cell. Unlike eukaryotic cells, bacteria usually lack large membrane-bound structures in their cytoplasm such as a nucleus, mitochondria, chloroplasts and the other organelles present in eukaryotic cells. However, some bacteria have protein-bound organelles in the cytoplasm which compartmentalize aspects of bacterial metabolism, such as the carboxysome. Additionally, bacteria have a multi-component cytoskeleton to control the localisation of proteins and nucleic acids within the cell, and to manage the process of cell division. Many important biochemical reactions, such as energy generation, occur due to concentration gradients across membranes, creating a potential difference analogous to a
Bacteria
19324473
TMS model has been reported for FtsW of "Streptococcus pneumoniae". The "S. pneumoniae" protein has both its N- and C-termini in the cytoplasm, a large (~ 60 residue) cytoplasmic domain between TMSs 4 and 5, and a large (~ 80 residue) extracytoplasmic loop between TMSs 7 and 8. Bacterial cell growth necessitates synthesis of peptidoglycan. Assembly of peptidoglycan is a multistep process starting in the cytoplasm and ending in the exterior cell surface. The intracellular part of the pathway results in the production of the membrane-anchored cell wall precursor, Lipid II. After synthesis, this lipid intermediate is translocated across the
Bacterial murein precursor exporter
7270593
change. After uncoating is completed, the active virus is released in the cytoplasm where replication of the genome and virion takes place. Replication of the virus takes places in the cytoplasm of the host cell. Since the genome of this virus is dsRNA, early transcription of the genome must take place inside the capsid where it is safe and will not be degraded by the host cell. dsRNA inside of a cell is a tip off to the immune system that the cell is infected with a virus, since dsRNA does not occur in the normal replication of a cell.
Orthoreovirus
1391898
a messenger RNA that is still in the process of being created. In eukaryotes translation can occur in a variety of regions of the cell depending on where the protein being written is supposed to be. Major locations are the cytoplasm for soluble cytoplasmic proteins and the membrane of the endoplasmic reticulum for proteins that are for export from the cell or insertion into a cell membrane. Proteins that are supposed to be expressed at the endoplasmic reticulum are recognised part-way through the translation process. This is governed by the signal recognition particle—a protein that binds to the ribosome and
Gene expression
13082368
several thyousand copies per cell, making a good target for microassays. Single nucleotide polymorphisms present in the bacterial rRNA sequence are used to differentiate bacteria at the genus, species and strain level. This is a unique feature of this microchip that does not require PCR based amplification. The process for detecting bacterial is relatively simple. The bacteria are cultured, washed and pelleted. Lysosome is used to lyse the pellets - to destroy the cell walls and release the nucleic acid. Lysed bacteria are passed through a colourmn preparation where nucleic acid from the cell is immobilized and other debris is
MAGIChip
2838316
bacterial cell can be assessed using plate assays. Bacteria are streaked across the agar, and are left to incubate. The release of the enzyme into the surroundings of the cell cause the breakdown of the macromolecule on the plate. If a reaction does not occur, this means that the bacteria does not create an exoenzyme capable of interacting with the surroundings. If a reaction does occur, it becomes clear that the bacteria does possess an exoenzyme, and which macromolecule is hydrolyzed determines its identity. Amylase breaks down carbohydrates into mono- and disaccharides, so a starch agar must be used for
Exoenzyme
7238049
DNA is not enclosed inside of a membrane-bound nucleus but instead resides inside the bacterial cytoplasm. This means that the transfer of cellular information through the processes of translation, transcription and DNA replication all occur within the same compartment and can interact with other cytoplasmic structures, most notably ribosomes. The bacterial DNA is not packaged using histones to form chromatin as in eukaryotes but instead exists as a highly compact supercoiled structure, the precise nature of which remains unclear. Most bacterial chromosomes are circular although some examples of linear DNA exist (e.g. "Borrelia burgdorferi"). Along with chromosomal DNA, most bacteria
Bacterial cell structure
1655866
Bacterial gliding Bacterial gliding is a process of motility whereby a bacterium can move under its own power. This process does not involve the use of flagella, pili, or fimbriae, all of which are more well-understood apparatuses used in bacterial motility. The mechanisms of gliding are only partially known. Generally, the process occurs whereby the bacterium moves along a surface in the general direction of its long axis. Gliding may occur via distinctly different mechanisms, depending on the type of bacterium. This type of movement has been observed in phylogenetically diverse bacteria such as cyanobacteria, myxobacteria, cytophaga, flavobacteria, and mycoplasmas,
Bacterial gliding
12780913
the bacteria and surface collector, the deposition could occur due to other interaction such as the steric impact of the presence of flagella on the cell environment and the strong hydrophobicity of the cell. Bacterial adhesion in aquatic system Bacterial adhesion involves the attachment (or deposition) of bacteria on the surface (solid, gel layer, etc.). This interaction plays an important role in natural system as well as in environmental engineering. The attachment of biomass on the membrane surface will result in membrane fouling, which can significantly reduce the efficiency of the treatment system using membrane filtration process in wastewater treatment
Bacterial adhesion in aquatic system
3052358
genome by homologous recombination. Transfer of DNA between bacterial cells can occur in three main ways. First, a bacterium can take up exogenous DNA released into the intervening medium from another bacterium by a process called transformation. DNA can also be transferred from one bacterium to another by the process of transduction, which is mediated by an infecting virus (bacteriophage). The third method of DNA transfer is "conjugation", in which a plasmid mediates transfer through direct cell contact between cells. Transformation, unlike transduction or conjugation, depends on numerous bacterial gene products that specifically interact to perform this complex process, and
Mating system
51239
an existing organism is transformed. During conjugation the "donor" cell provides a conjugative or mobilizable genetic element that is most often a plasmid or transposon. Most conjugative plasmids have systems ensuring that the "recipient" cell does not already contain a similar element. The genetic information transferred is often beneficial to the recipient. Benefits may include antibiotic resistance, xenobiotic tolerance or the ability to use new metabolites. Such beneficial plasmids may be considered bacterial endosymbionts. Other elements, however, may be viewed as bacterial parasites and conjugation as a mechanism evolved by them to allow for their spread. The process was discovered
Bacterial conjugation
7238044
generally short in length and present in high numbers about the entire bacterial cell surface. Fimbriae usually function to facilitate the attachment of a bacterium to a surface (e.g. to form a biofilm) or to other cells (e.g. animal cells during pathogenesis). A few organisms (e.g. "Myxococcus") use fimbriae for motility to facilitate the assembly of multicellular structures such as fruiting bodies. Pili are similar in structure to fimbriae but are much longer and present on the bacterial cell in low numbers. Pili are involved in the process of bacterial conjugation where they are called conjugation pili or "sex pili".
Bacterial cell structure
1906425
ER for future vesicle transport and secretion outside the cell, or immediately secreted. Many types of transcribed RNA, such as transfer RNA, ribosomal RNA, and small nuclear RNA, do not undergo translation into proteins. A number of antibiotics act by inhibiting translation. These include clindamycin, anisomycin, cycloheximide, chloramphenicol, tetracycline, streptomycin, erythromycin, and puromycin. Prokaryotic ribosomes have a different structure from that of eukaryotic ribosomes, and thus antibiotics can specifically target bacterial infections without any harm to a eukaryotic host's cells. The basic process of translation is the addition of three amino acids at a time to the end of the
Translation (biology)
3251005
continues to infect another bacterial cell. This bacterial material may become recombined into another bacterium upon infection. When the new DNA is inserted into this recipient cell it can fall to one of three fates "Specialized transduction" is the process by which a "restricted" set of bacterial genes is transferred to another bacterium. The genes that get transferred (donor genes) depend on where the phage genome is located on the chromosome. Specialized transduction occurs when the prophage excises imprecisely from the chromosome so that bacterial genes lying adjacent to the prophage are included in the excised DNA. The excised DNA
Transduction (genetics)
7238034
for a large surface area-to-volume ratio which allows for rapid uptake and intracellular distribution of nutrients and excretion of wastes. At low surface area-to-volume ratios the diffusion of nutrients and waste products across the bacterial cell membrane limits the rate at which microbial metabolism can occur, making the cell less evolutionarily fit. The reason for the existence of large cells is unknown, although it is speculated that the increased cell volume is used primarily for storage of excess nutrients. The cell envelope is composed of the plasma membrane and cell wall. As in other organisms, the bacterial cell wall provides
Bacterial cell structure
16820749
tissue plasminogen activator. This technology was applied to sheep, pigs, cows and other livestock. In 2010 scientists at the J. Craig Venter Institute announced that they had created the first synthetic bacterial genome. The researchers added the new genome to bacterial cells and selected for cells that contained the new genome. To do this the cells undergoes a process called resolution, where during bacterial cell division one new cell receives the original DNA genome of the bacteria, whilst the other receives the new synthetic genome. When this cell replicates it uses the synthetic genome as its template. The resulting bacterium
History of genetic engineering
20891331
targets specific proteins to the endoplasmic reticulum in eukaryotes and to the cell membrane in prokaryotes. The two pathways require different molecular chaperones and ultimately use a protein-transporting channel SecYEG for transporting the proteins across the inner cell membrane. In the SecA pathway, SecB acts as a chaperone, helping protein transport to the periplasm after complete synthesis of the peptide chains. Whereas in the SRP pathway, YidC is the chaperone, and transport proteins to the cell membrane while they are still undergoing peptide synthesis. Proteins are synthesised in ribosomes by a process of serially adding amino acids, called translation. In
Bacterial secretion system
278118
interphase nuclei. During mitotic progression, typically after the anaphase onset, the cell may undergo cytokinesis. In animal cells, a cell membrane pinches inward between the two developing nuclei to produce two new cells. In plant cells, a cell plate forms between the two nuclei. Cytokinesis does not always occur; coenocytic (a type of multinucleate condition) cells undergo mitosis without cytokinesis. The mitotic phase is a relatively short period of the cell cycle. It alternates with the much longer "interphase", where the cell prepares itself for the process of cell division. Interphase is divided into three phases: G (first gap), S
Mitosis
3755246
animal and protozoa cells which do not have cell walls. The reverse process is plasmolysis. Osmotic lysis is often one result of a stroke, because of improper nutrient perfusion and waste removal alter cell metabolism. Such malfunction results in an inflow of extracellular fluid into the cells. Osmotic lysis would be expected to occur when bacterial cells are treated with a hypotonic solution with added lysozyme, which destroys the bacteria's cell walls. Different cells and organisms have adapted different ways of preventing cytolysis from occurring. For example, the paramecium uses a contractile vacuole, which rapidly pumps out excessive water to
Cytolysis
11388307
to its target does not permeabilize the bacterial cell wall like defensins and other antimicrobial peptides. Instead, PGLYRP1 binding activates a bacterial stress response that causes the bacterium to shut down transcription and translation, and induces oxidative stress. As a cytotoxic agent, the PGLYRP1-HSP70 complex In humans, single nuclear polymorphisms of the "PGLYRP1" gene have been associated with the development of ulcerative colitis. In mice, the lack of "PGLYRP1" is associated with increased susceptibility to infectious disease, but also decreased susceptibility to autoimmune disease. The lack of "PGLYRP1" was found to have increased susceptibility to corneal infections, reduced corneal wound
Peptidoglycan recognition protein 1
11265154
amino acid building blocks based on information coded in DNA. Each type of protein is a specialist that usually only performs one function, so if a cell needs to do something new, it must make a new protein. Viruses force the cell to make new proteins that the cell does not need, but are needed for the virus to reproduce. Protein synthesis consists of two major steps: transcription and translation. Transcription is the process where information in DNA, called the genetic code, is used to produce RNA copies called messenger RNA (mRNA). These migrate through the cell and carry the
Introduction to viruses
11631418
translation mechanisms. IVC has used bacterial cell, wheat germ and rabbit reticulocyte (RRL) extracts for transcription and translation. It is also possible to use bacterial reconstituted translation system such as PURE in which translation components are individually purified and later combined. When expressing eukaryote or complex proteins, it is desirable to use eukaryotic translation systems such as wheat germ extract or more superior alternative, RRL extract. In order to use RRL for transcription and translation, traditional emulsion formulation cannot be used as it abolishes translation. Instead, a novel emulsion formulation: 4% Abil EM90 / light mineral oil was developed and
In vitro compartmentalization
20968757
increasing Ca availability and increasing pH will increase the rate of mineralization. Negatively charged surfaces on microbes have a high affinity for cations such as Ca and, though metabolic function, increase saturation of CO in solution. In addition, bacterial ureolysis (hydrolysis of urea) increases pH of the solution. The microbial electrolytic process uses wastewater as a source of charged ions and outputs hydrogen gas through the use of the microbial electrolysis cell. The wastewater itself provides electrolytes and is used to dissolve minerals. It is in the wastewater where reactions occur that bind CO molecules to make new substances. On
Microbial electrolysis carbon capture
3031420
protein synthesis inhibitors, though additional mechanisms are implicated for some specific agents, and/or thorough mechanistic descriptions are as yet unavailable. The inhibition of protein synthesis is mediated through aminoglycosides' energy-dependent, sometimes irreversible binding, to the cytosolic, membrane-associated bacterial ribosome (image at right). (Aminoglycosides first cross bacterial cell walls—lipopolysaccharide in gram-negative bacteria—and cell membranes, where they are actively transported.) While specific steps in protein synthesis affected may vary somewhat between specific aminoglycoside agents, as can their affinity and degree of binding, aminoglycoside presence in the cytosol generally disturbs peptide elongation at the 30S ribosomal subunit, giving rise to inaccurate mRNA translation
Aminoglycoside
10969507
Nic site The "nic" site or nick region is found within the origin of transfer ("oriT") site and is a key in starting bacterial conjugation.[1] A single strand of DNA, called the T-strand, is cut at "nic" by an enzyme called relaxase. This single strand is eventually transferred to the recipient cell during the process of bacterial conjugation. Before this cleavage can occur, however, it is necessary for a group of proteins to attach to the "oriT" site. This group of proteins is called the relaxosome. It is thought that portions of the "oriT" site are bent in a way
Nic site
499598
Bacterial growth Bacterial growth is the asexual reproduction, or cell division, of a bacterium into two daughter cells, in a process called binary fission. Providing no mutational event occurs, the resulting daughter cells are genetically identical to the original cell. Hence, bacterial growth occurs. Both daughter cells from the division do not necessarily survive. However, if the number surviving exceeds unity on average, the bacterial population undergoes exponential growth. The measurement of an exponential bacterial growth curve in batch culture was traditionally a part of the training of all microbiologists; the basic means requires bacterial enumeration (cell counting) by direct
Bacterial growth
3598193
when concomitant oral or genital lesions occur, significantly affects patients’ quality of life. The cause of lichen planus is unknown, but it is not contagious and does not involve any known pathogen. It is thought to be a T cell mediated autoimmune reaction (where the body's immune system targets its own tissues). This autoimmune process triggers apoptosis of the epithelial cells. Several cytokines are involved in lichen planus, including tumor necrosis factor alpha, interferon gamma, interleukin-1 alpha, interleukin 6, and interleukin 8. This autoimmune, T cell mediated, process is thought to be in response to some antigenic change in the
Lichen planus
1851766
the RNA genome has 2 U’s attached to it. The purpose of these U’s is to modify the VPg protein which serves as a protein primer which the viral RdRP can recognize and start forming more genome from the negative-sense. The viral protein 2C brings positive sense RNA genomes to the endoplasmic reticulum where assembly and maturation will occur. While all of this is occurring, viral proteinases are working to turn off host cell protein synthesis by cleaving the eIF-4 initiation factor. This process accomplishes the inhibition of ribosomes binding to host cell mRNAs. This effectively shuts down cap-dependent translation
Coxsackie B4 virus
3251001
viruses, including bacteriophages (viruses that infect bacteria), infect bacterial cells, their normal mode of reproduction is to harness the replicational, transcriptional, and translation machinery of the host bacterial cell to make numerous virions, or complete viral particles, including the viral DNA or RNA and the protein coat. Transduction was discovered by Norton Zinder and Joshua Lederberg at the University of Wisconsin–Madison in 1952 in Salmonella. Transduction happens through either the lytic cycle or the lysogenic cycle. If the lysogenic cycle is adopted, the phage chromosome is integrated (by covalent bonds) into the bacterial chromosome, where it can stay dormant for
Transduction (genetics)
7207670
example, Spratt (1977) reports that six different PBPs are routinely detected in all strains of "E. coli" ranging in molecular weight from 40,000 to 91,000. The different PBPs occur in different numbers per cell and have varied affinities for penicillin (see appendix). The PBPs are usually broadly classified into high-molecular-weight (HMW) and low-molecular-weight (LMW) categories. Proteins that have evolved from PBPs occur in many higher organisms and include the mammalian LACTB protein. PBPs are all involved in the final stages of the synthesis of peptidoglycan, which is the major component of bacterial cell walls. Bacterial cell wall synthesis is essential
Penicillin binding proteins
3031422
ribosomal structures that lead to the infidelities in translation (ibid.). Inhibition of ribosomal translocation—i.e., movement of the peptidyl-tRNA from the A- to the P-site—has also been suggested. (Spectinomycin, a related but distinct chemical structure class often discussed with aminoglycosides, does not induce mRNA misreading and is generally not bactericidal.) Finally, a further "cell-membrane effect" also occurs with aminoglycosides; "functional integrity of the bacterial cell membrane" can be lost, later in time courses of aminoglycoside exposure and transport. There is a significant variability in the relationship between the dose administered and the resultant plasma level in blood. Therapeutic drug monitoring (TDM)
Aminoglycoside
15567091
Phage-ligand technology The Phage-ligand technology is a technology to detect, bind and remove bacteria and bacterial toxins by using highly specific bacteriophage derived proteins. The host recognition of bacteriophages occur via bacteria-binding proteins that have strong binding affinities to specific protein or carbohydrate structures on the surface of the bacterial host. At the end of the infection life cycle the bacteria-lysing Endolysin is synthesized and degrades the bacterial peptidoglycan cell wall, resulting in lysis (and therefore killing) of the bacterial cell. Bacteriophage derived proteins are used for detection and removal of bacteria and bacterial components (especially endotoxin contaminations) in pharmaceutical
Phage-ligand technology
6849914
provide for antibiotic resistance or other advantages. Regardless of the nature of selection for competence, the composite nature of bacterial genomes provides abundant evidence that the horizontal gene transfer caused by competence contributes to the genetic diversity that makes evolution possible. Natural competence In microbiology, genetics, cell biology, and molecular biology, competence is the ability of a cell to alter its genetics by taking up extracellular ("naked") DNA from its environment in the process called transformation. Competence may be differentiated between "natural competence", a genetically specified ability of bacteria which is thought to occur under natural conditions as well as
Natural competence
1187013
cell resulting from the direct uptake and incorporation of exogenous DNA from its surroundings. For bacterial transformation to take place, the recipient bacteria must be in a state of competence, which may occur in nature as a response to conditions such as starvation, high cell density or exposure to DNA damaging agents. In chromosomal transformation, homologous transforming DNA can be integrated into the recipient genome by homologous recombination, and this process appears to be an adaptation for repairing DNA damage. Historically, bacteria were first classified as plants constituting the class Schizomycetes, which along with the Schizophyceae (blue-green algae/Cyanobacteria) formed the
Cyanobacteria
19530413
of the T even bacteriophage tail plays a role in the attachment site. Therefore, there must be specific receptor attachment as the receptor determines the host preference. Penetration This stage involves for the virus to penetrate itself in the host cell. It does so by injecting its DNA into the cell. The process of penetration happens when the bacteriophage's tail secretes the enzyme lysozyme, which breaks down the bacterial cell wall into segments. Therefore, the break down of the cell by the enzyme lysozyme forms a hole on the host cell;so, the bacteriophage inserts the DNA (genetic material) within the
T-even bacteriophages
937542
cycle. During the prophase in the process of cell division called mitosis, the centrosomes migrate to opposite poles of the cell. The mitotic spindle then forms between the two centrosomes. Upon division, each daughter cell receives one centrosome. Aberrant numbers of centrosomes in a cell have been associated with cancer. Doubling of a centrosome is similar to DNA replication in two respects: the semiconservative nature of the process and the action of CDK2 as a regulator of the process. But the processes are essentially different in that centrosome doubling does not occur by template reading and assembly. The mother centriole
Centrosome
20469484
detachments, in turn, lead to limited cellular energy through the drop in the level of ATP and it undermines the cell wall integrity. Additionally, MP196 leads to osmotic destabilization in bacterial cells. These factors lead to bacterial cell death.MP196 does not need to be stereospecific to bring about bacterial cell death. When MP196 was equally effective when synthesized with all D amino acids or all L amino acids. MP196 is shown to be effective against some strains of methicillin-resistant "Staphylococcus aureus" (MRSA) and vancomycin intermediate-resistant "Staphylococcus aureus" (VISA). MP196 brings about bacterial cell death through a wide variety of mechanisms,
MP196
8159948
and its recombinational incorporation into the recipient chromosome depends on the expression of numerous bacterial genes whose products direct this process. In general, transformation is a complex, energy-requiring developmental process that appears to be an adaptation for repairing DNA damage. Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. Bacterial conjugation has been extensively studied in "Escherichia coli", but also occurs in other bacteria such as "Mycobacterium smegmatis". Conjugation requires stable and extended contact between a donor and a recipient strain, is DNase resistant, and the
Microbial genetics
7108569
modern eukaryotic nucleus may have relied on multiple infections of archaeal cells carrying bacterial mitochondrial precursors with lysogenic viruses. The viral eukaryogenesis hypothesis depicts a model of eukaryotic evolution in which a virus, similar to a modern pox virus, evolved into a nucleus via gene acquisition from existing bacterial and archaeal species. The lysogenic virus then became the information storage center for the cell, while the cell retained its capacities for gene translation and general function despite the viral genome's entry. Similarly, the bacterial species involved in this eukaryogenesis retained its capacity to produce energy in the form of ATP
Viral eukaryogenesis
3251000
Transduction (genetics) Transduction is the process by which foreign DNA is introduced into a cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another and hence an example of horizontal gene transfer. Transduction does not require physical contact between the cell donating the DNA and the cell receiving the DNA (which occurs in conjugation), and it is DNase resistant (transformation is susceptible to DNase). Transduction is a common tool used by molecular biologists to stably introduce a foreign gene into a host cell's genome (both bacterial and mammalian cells). When
Transduction (genetics)
43645
the S phase of the cell cycle. In meiosis, the DNA is replicated only once, while the cell divides twice. DNA replication only occurs before meiosis I. DNA replication does not occur when the cells divide the second time, in meiosis II. Replication, like all cellular activities, requires specialized proteins for carrying out the job. Between successive cell divisions, cells grow through the functioning of cellular metabolism. Cell metabolism is the process by which individual cells process nutrient molecules. Metabolism has two distinct divisions: catabolism, in which the cell breaks down complex molecules to produce energy and reducing power, and
Cell (biology)
9564129
distributed over the surface of the cell, and resemble fine hairs when seen under the electron microscope. Fimbriae are believed to be involved in attachment to solid surfaces or to other cells, and are essential for the virulence of some bacterial pathogens. Pili ("sing". pilus) are cellular appendages, slightly larger than fimbriae, that can transfer genetic material between bacterial cells in a process called conjugation where they are called conjugation pili or sex pili (see bacterial genetics, below). They can also generate movement where they are called type IV pili. Glycocalyx is produced by many bacteria to surround their cells,
Bacteria
15786246
quickly and the bacterial cells relay on a cell to cell communication method called Quorum sensing. In Quorum sensing the cells communicate with each other via small signaling molecules. The bacterial cells can reproduce in the intercellular spaces and can generate enzymes that degrade or destroy the plant cell wall. Once the cell wall is degraded a liquification of the stem and the original seed tuber occurs. New tubers growing alongside the diseased tuber may become contaminated in the late summer into the early fall. During harvest, mechanical injuries can occur on the tuber which can provide more entry spots
Dickeya solani
2465565
toxin kept "within" the bacterial cell and released only after destruction of the bacterial cell wall. Subsequent work showed that release of LPS from gram negative microbes does not necessarily require the destruction of the bacterial cell wall, but rather, LPS is secreted as part of the normal physiological activity of membrane vesicle trafficking in the form of bacterial outer membrane vesicles (OMVs), which may also contain other virulence factors and proteins. Today, the term 'endotoxin' is mostly used synonymously with LPS, although there are a few endotoxins that are not related to LPS, such as the so-called delta endotoxin
Lipopolysaccharide
19530411
(T4-like phage) mechanism of penetration and it has shown that the phages tail does not penetrate inside the bacterial cell wall and penetration of this phage involves electrochemical membrane potential on the inner membrane. Virulent bacteriophages multiply in their bacterial host immediately after entry. After the number of progeny phages reach a certain amount, they cause the host to lyse or break down, therefore they would be released and infect new host cells. The process of host lyses and release is called the lytic cycle. Lytic cycle is a cycle of viral reproduction that involves the destruction of the infected
T-even bacteriophages
3489013
daughter cells after it undergoes mitosis. As a consequence, the DNA repair process is constantly active as it responds to damage in the DNA structure. When normal repair processes fail, and when cellular apoptosis does not occur, irreparable DNA damage may occur, including double-strand breaks and DNA crosslinkages (interstrand crosslinks or ICLs). This can eventually lead to malignant tumors, or cancer as per the two hit hypothesis. The rate of DNA repair is dependent on many factors, including the cell type, the age of the cell, and the extracellular environment. A cell that has accumulated a large amount of DNA
DNA repair
15682284
between two cells. Discovered in 1946 by Joshua Lederberg and Edward Tatum, conjugation is a mechanism of horizontal gene transfer as are transformation and transduction although these two other mechanisms do not involve cell-to-cell contact. Bacterial conjugation is often regarded as the bacterial equivalent of sexual reproduction or mating since it involves the exchange of genetic material. During conjugation the donor cell provides a conjugative or mobilizable genetic element that is most often a plasmid or transposon.[4][5] Most conjugative plasmids have systems ensuring that the recipient cell does not already contain a similar element. The genetic information transferred is often
Bacterial genetics
664328
depends on the gene it is transcribed from and on the current physiological state of the cell. Proteomics confirms the presence of the protein and provides a direct measure of the quantity present. Not only does the translation from mRNA cause differences, but many proteins also are subjected to a wide variety of chemical modifications after translation. Many of these post-translational modifications are critical to the protein's function. One such modification is phosphorylation, which happens to many enzymes and structural proteins in the process of cell signaling. The addition of a phosphate to particular amino acids—most commonly serine and threonine
Proteomics
1655870
large macromolecular assemblies located on the bacterium's cell body, while yet another utilize "focal adhesion complexes" and "treadmilling" of surface adhesins distributed along the cell body. The gliding motility of "Flavobacterium johnsoniae" uses a helical track superficially similar to "M. xanthus", but via a different mechanism. Here the adhesin SprB is propelled along the cell surface (spiraling from pole to pole), pulling the bacterium along 25 times faster than "M. xanthus". "Flavobacterium johnsoniae" move via a screw-like mechanism and are powered by a proton motive force. Bacterial gliding Bacterial gliding is a process of motility whereby a bacterium can move
Bacterial gliding
17199702
of copies. The main draw backs to using MALBA, is it has reduced accuracy compared to DOP-PCR and MDA due to the enzyme used to copy the DNA. Once amplified using any of the above techniques, the DNA can be sequenced using Sanger or next-generation sequencing (NGS). There are two major applications to studying the genome at the single cell level. One application is to track the changes that occur in bacterial populations, where phenotypic differences are often seen. These differences are missed by bulk sequencing of a population, but can be observed in single cell sequencing. The second major
Single-cell analysis
16687650
is to help cell adhesion and to increase virulence. YadA is a collagen-binding outer membrane protein. It forms the fibrillar matrix on the bacterial cell surface. This aids cell attachment and helps the bacteria invade eukaryotic cells. Additionally, by forming the fibrillar matrix, the YadA domain protects the bacteria by facilitating agglutination resistance, serum resistance, complement inactivation and phagocytosis resistance. The importance of adhesins to YadA function and "Yersinia" survival is huge. Attachment further allows more interactions and increase of biofilm formation to aid bacterial colonization. In "Yersinia", it helps initiate the infectious process in host cells and are critical
YadA bacterial adhesin protein domain
18088505
in activation of ClpP. This binding initiates ClpP to undergo a conformational change such that its N-terminal region opens up its axial pore to allow for partial degradation of products, as compared to progressive degradation with ClpA. ADEP activation of ClpP does not allow for folded protein degradation, but even with unfolded protein and peptide degradation, ADEP still causes bacterial cell death. Research has shown that ADEP-activated ClpP targets cell division rather than metabolic processes. ADEP appears to initiate ClpP to preferably degrade FtsZ, an important bacterial protein involved in septum formation that is necessary for bacterial cell division. As
Acyldepsipeptide antibiotics
2826293
cholera toxin in pathogenic bacteria for example "Vibrio cholerae") from across the interior (cytoplasm or cytosol) of a bacterial cell to its exterior. Secretion is a very important mechanism in bacterial functioning and operation in their natural surrounding environment for adaptation and survival. Eukaryotic cells, including human cells, have a highly evolved process of secretion. Proteins targeted for the outside are synthesized by ribosomes docked to the rough endoplasmic reticulum (ER). As they are synthesized, these proteins translocate into the ER lumen, where they are glycosylated and where molecular chaperones aid protein folding. Misfolded proteins are usually identified here and
Secretion
12425353
of cell function, relating mostly to transcription, translation, and nucleotide metabolism. Other characteristic archaeal features are the organization of genes of related function—such as enzymes that catalyze steps in the same metabolic pathway into novel operons, and large differences in tRNA genes and their aminoacyl tRNA synthetases. Transcription in archaea more closely resembles eukaryotic than bacterial transcription, with the archaeal RNA polymerase being very close to its equivalent in eukaryotes; while archaeal translation shows signs of both bacterial and eukaryal equivalents. Although archaea only have one type of RNA polymerase, its structure and function in transcription seems to be close
Archaea
3924758
bioluminescence is regulated by autoinduction. An autoinducer is a transcriptional promoter of the enzymes necessary for bioluminescence. Before the glow can be luminized, a certain concentration of an autoinducer must be present. So, for bioluminescence to occur, high colony concentrations of "A. fischeri" should be present in the organism. Natural bacterial transformation is an adaptation for transferring DNA from one individual cell to another. Natural transformation, including the uptake and incorporation of exogenous DNA into the recipient genome, has been demonstrated in "A. fischeri". This process requires induction by chitohexaose and is likely regulated by genes "tfoX" and "tfoY". Natural
Aliivibrio fischeri
11239915
way to produce a signal and a way to respond to that signal. These cellular processes are often tightly coordinated and involve changes in gene expression. The production of autoinducers generally increases as bacterial cell densities increase. Most signals are produced intracellularly and are subsequently secreted in the extracellular environment. Detection of autoinducers often involves diffusion back into cells and binding to specific receptors. Usually, binding of autoinducers to receptors does not occur until a threshold concentration of autoinducers is achieved. Once this has occurred, bound receptors alter gene expression either directly or indirectly. Some receptors are transcription factors themselves,
Autoinducer
611110
lung disease, as well as an increased burden of chronic bacterial infections. Several mutations in the "CFTR" gene can occur, and different mutations cause different defects in the CFTR protein, sometimes causing a milder or more severe disease. These protein defects are also targets for drugs which can sometimes restore their function. ΔF508-CFTR, which occurs in >90% of patients in the U.S., creates a protein that does not fold normally and is not appropriately transported to the cell membrane, resulting in its degradation. Other mutations result in proteins that are too short (truncated) because production is ended prematurely. Other mutations
Cystic fibrosis
15580339
Paracytophagy Paracytophagy () is the cellular process whereby a cell engulfs a protrusion which extends from a neighboring cell. This protrusion may contain material which is actively transferred between the cells. The process of paracytophagy was first described as a crucial step during cell-to-cell spread of the intracellular bacterial pathogen "Listeria monocytogenes", and is also commonly observed in "Shigella flexneri". Paracytophagy allows these intracellular pathogens to spread directly from cell to cell, thus escaping immune detection and destruction. Studies of this process have contributed significantly to our understanding of the role of the actin cytoskeleton in eukaryotic cells. Actin is
Paracytophagy
19119599
as dinoflagellates. The structure of the nucleoid has been implicated in the unusual radiation tolerance of "G. obscuriglobus". Transcription and translation of genes have been reported to occur in spatially segregated locations within the cell, which is otherwise characteristic of eukaryotic but not prokaryotic cells. "G. obscuriglobus" is one of the few prokaryotes known to synthesize sterols, a process critical to the maintenance of eukaryotic cell membranes and ubiquitous in eukaryotes. The sterols identified in the bacterium, lanosterol and parkeol, are relatively simple compared to eukaryotic sterols; as indicated by phylogenetic analysis, the "G. obscuriglobus" sterol biosynthetic pathway was among
Gemmata obscuriglobus
13779228
These techniques lose dynamic information from individual cells and give the impression that transcription is a continuous smooth process. Observed at an individual cell level, transcription is irregular, with strong periods of activity interspersed by long periods of inactivity. Bursting may result from the stochastic nature of biochemical events superimposed upon a two step fluctuation. In its most simple form, the gene is proposed to exist in two states, one where activity is negligible and one where there is a certain probability of activation. Only in the second state does transcription readily occur. It seems likely that some rudimentary eukaryotes
Transcriptional bursting
18211497
eminent Australian and international researchers to the institute, including that of our current Director, Professor Ian Charles. Professor Harry's research on bacterial cell division has had a significant impact on our understanding of how bacterial cells multiply, and how they control this process to ensure equal partitioning of chromosomes vital for survival. Her research has often changed the direction of thinking in the field, and has afforded excellent opportunities in antibacterial discovery. Her cutting-edge cell biology techniques including super resolution microscopy have provided unique insights in the mechanism and spatiotemporal control of the division process in bacteria. She made the
Elizabeth Harry
9997261
contrast to the catalytic domain, the cell-binding domain is variable, which allows a great specificity and decreases bacterial resistance. Binding affinity to the cell wall substrate tends to be high, possibly so as to sequester onto cell wall fragments any free enzyme, which could compete with phage progeny from infecting adjacent host bacteria. It has been proposed that the main mechanism of evolution in phage lysins is the exchange of modular units, a process by which different catalytic and cell-binding domains have been swapped between lysins, which would have resulted in new combinations of both bacterial binding and catalytic specificities.
Lysin
6295395
is a broad-spectrum antibiotic that is active against both Gram-positive and Gram-negative bacteria. It functions by inhibiting DNA gyrase, a type II topoisomerase, and topoisomerase IV, enzymes necessary to separate bacterial DNA, thereby inhibiting cell division. Norfloxacin does not bind to DNA gyrase but does bind to the substrate DNA. A review in 2001 suggests that Cytotoxicity of fluoroquinolones is likely a 2-step process involving (1) conversion of the topoisomerase-quinolone-DNA complex to an irreversible form and (2) generation of a double-strand break by denaturation of the topoisomerase. As noted above, under licensed use, norfloxacin is also now considered to be
Norfloxacin
1407095
occur within a single bacterial species, as well as between diverse species. Both Gram-positive and gram-negative bacteria use quorum sensing, but there are some major differences in their mechanisms. For the bacteria to use quorum sensing constitutively, they must possess three characteristics: to secrete a signaling molecule, an autoinducer, to detect the change in concentration of signaling molecules, and to regulate gene transcription as a response. This process is highly dependent on the diffusion mechanism of the signaling molecules. QS Signaling molecules are usually secreted at a low level by individual bacteria. At low cell density, the molecules may just
Quorum sensing
2946373
million bases). The length transferred is likely double stranded DNA and is often more than a third of the total chromosome length of 4215 kb. It appears that about 7-9% of the recipient cells take up an entire chromosome. The capacity for natural transformation appears to occur in a number of prokaryotes, and thus far 67 prokaryotic species (in seven different phyla) are known to undergo this process. Competence for transformation is typically induced by high cell density and/or nutritional limitation, conditions associated with the stationary phase of bacterial growth. Transformation in "Haemophilus influenzae" occurs most efficiently at the end
Transformation (genetics)
14273448
advanced cytoskeleton was necessary to organize the chromosomes during asexual cell replication. After the loss of the rigid bacterial outer wall, the advanced cytoskeleton allowed the cells to flow and move. The loss of the rigid bacterial cell wall, which helped prevent water from entering the cell and diluting the cytoplasm, required ancestral eukaryotes to develop pumping mechanisms to counteract osmosis. Once the advanced cytoskeleton was in place and cell wall removed, ancestral eukaryotic cells had the ability to flow around and engulf other cells using the process of phagocytosis, which is a more efficient way of obtaining nutrients than
Boring Billion
18818582
quorum sensing, a process of cell-to-cell bacterial communication. As of June 2015, he is a professor at the University of Washington and his lab studies fields such as quorum sensing and biofilms. Greenberg was elected to the National Academy of Sciences in 2004. In 2015, Greenberg and Bonnie Bassler of Princeton University were awarded the Shaw Prize in Life Science and Medicine "for their discovery of quorum sensing, a process whereby bacteria communicate with each other and which offers innovative ways to interfere with bacterial pathogens or to modulate the microbiome for health applications." Everett Peter Greenberg Everett Peter Greenberg
Everett Peter Greenberg
20302419
but some are unresponsive to bacteria. In "Arabidopsis" "Xcc" does not revert bacteria-induced or ABA-induced stomatal closure. Scientists are not certain if MAPK cascades are responsible for the signaling, so further investigation is needed for this. The identification of MEKK1-MKK1/2-MPK4 in pathogen signaling has been a tremendous finding. "Mekk1, mkk1/mkk2" double and "mpk4" mutations are dwarfed and acquire too much of reactive oxygen species. The mutations are considered to be from the enhancement of SA levels, which is partially reversed by bacterial SA hydrolase. "Mekk1, mkk1/mkk2" double and "mpk4" mutations have cell death occur spontaneously, pathogenesis-related genes and increased resistance
MAPK networks
2818638
Cell adhesion Cell adhesion is the process by which cells interact and attach to neighbouring cells through specialised molecules of the cell surface. This process can occur either through direct contact between cell surfaces or indirect interaction, where cells attach to surrounding extracellular matrix, a gel-like structure containing molecules released by cells into spaces between them. Cells adhesion occurs from the interactions between cell-adhesion molecules (CAMs), transmembrane proteins located on the cell surface. Cell adhesion link cells in different ways and can be involved in signal transduction for cells to detect and respond to changes in the surroundings. Other cellular
Cell adhesion
3049568
referred to as a "morula." It is possible for errors to occur during this process of repetitive cell division. Common among these errors is for the genetic material to not be divided evenly. Normally, when a cell divides each daughter cell has the same genetic material as the parent cell. If the genetic material does not split evenly between the two daughter cells, an event called "nondisjunction" occurs. Since this event occurs in only one of the several cells that exist at this point, the embryo will continue to develop but will have some normal cells and some abnormal cells.
Blastomere
19495329
began to study the phenomenon of neoplasms in plants. Building on early grafting studies in plants as well as work by other researchers that demonstrated the transfer of genetic material between bacteria, they hypothesized that a similar phenomenon might occur between bacterial cells and plants. Their research in the late 1960s demonstrated that this process did indeed exist and led them to study whether a similar mechanism occurred in higher-order species, where Stroun published further research showing transfer of genetic material from bacteria to frogs. In an article published in "Science", November 10, 1972, bacterial RNA was demonstrated in frog
Maurice Stroun
15580353
directly in an efficient manner, and the previously described macrophage hand-off is thought to be necessary for this mode of spread. The process of paracytophagy is considered distinct from similar but unrelated processes such as phagocytosis and trogocytosis. Some related concepts include: Paracytophagy Paracytophagy () is the cellular process whereby a cell engulfs a protrusion which extends from a neighboring cell. This protrusion may contain material which is actively transferred between the cells. The process of paracytophagy was first described as a crucial step during cell-to-cell spread of the intracellular bacterial pathogen "Listeria monocytogenes", and is also commonly observed in
Paracytophagy
91157
cytokinesis together define the division of the mother cell into two daughter cells, genetically identical to each other and to their parent cell. This accounts for approximately 10% of the cell cycle. Because cytokinesis usually occurs in conjunction with mitosis, "mitosis" is often used interchangeably with "M phase". However, there are many cells where mitosis and cytokinesis occur separately, forming single cells with multiple nuclei in a process called endoreplication. This occurs most notably among the fungi and slime moulds, but is found in various groups. Even in animals, cytokinesis and mitosis may occur independently, for instance during certain stages
Cell cycle
12886876
levels of lactate in CSF indicate a higher likelihood of bacterial meningitis, as does a higher white blood cell count. If lactate levels are less than 35 mg/dl and the person has not previously received antibiotics then this may rule out bacterial meningitis. A diagnostic and therapeutic difficulty is "partially treated meningitis", where there are meningitis symptoms after receiving antibiotics (such as for presumptive sinusitis). When this happens, CSF findings may resemble those of viral meningitis, but antibiotic treatment may need to be continued until there is definitive positive evidence of a viral cause (e.g. a positive enterovirus PCR). Meningitis
Meningitis
20751810
sibling cells which are in possession of the immunity protein BcpI. This change in gene expression leads to increased biofilm formation in the bacterial population through a phenomenon now known as Contact-Dependent Signalling. Furthermore, the T6SS in "V. cholerae" is active in biofilms, enabling a cell expressing T6SS to kill nearby cells which do not have the specific immunity. Contact-dependent growth inhibition Contact-dependent growth inhibition (CDI) is a phenomenon where a bacterial cell may deliver a polymorphic toxin molecule into neighbouring bacterial cells upon direct cell-cell contact, causing growth arrest or cell death. CDI is now a blanket term to
Contact-dependent growth inhibition
10607182
quickly degrades. If a daughter cell has inherited the R1 plasmid, it has inherited the "sok" gene and a strong promoter which brings about high levels of transcription. So much so that in an R1-positive cell, Sok transcript exists in considerable molar excess over Hok mRNA. Sok RNA then indirectly inhibits the translation of "hok" by inhibiting "mok" translation. There is a complementary region where "sok" transcript binds "hok" mRNA directly ("pictured"), but it does not occlude the Shine-Dalgarno sequence. Instead, "sok" RNA regulates the translation of the "mok" open reading frame, which nearly entirely overlaps that of "hok". It
Hok/sok system
8554817
Antigen presentation Antigen presentation describes a vital immune process which is essential for T cell immune response triggering. Because T cells recognise only fragmented antigens displayed on cell surfaces, antigen processing must occur before the antigen fragment, now bound to the major histocompatibility complex (MHC), is transported to the surface of the cell, a process known as presentation, where it can be recognized by a T cell receptor. If there has been an infection with viruses or bacteria, the cell will present an endogenous or exogenous peptide fragment derived from the antigen bound to MHC molecules. There are two types
Antigen presentation
14322684
electrode in an electrochemical cell. As a result of its properties Nyex can undergo quick adsorption and fast electrochemical regeneration in a combined adsorption-electrochemical regeneration cell achieving 100% regeneration efficiency. The adsorption regeneration process is divided into three key elements which occur in different parts of the cell. All three occur continuously and simultaneously, with parameters such as charge passed, rate of effluent in/outflow and air inlet rate varied according to pollutant type and concentration. Polluted effluent is added into the bottom of the cell and mixed with the adsorbent in the adsorption zone 1.1 where adsorption of the pollutants
Continuous adsorption-regeneration
12971363
transport along the axon. While neuronal mitophagy is thought to occur primarily in the cell body, it also occurs locally in the axon at sites distant from the cell body; in both the cell body and the axon, neuronal mitophagy occurs via the PINK1-Parkin pathway. Mitophagy in the nervous system may also occur transcellularly, where damaged mitochondria in retinal ganglion cell axons can be passed to neighboring astrocytes for degradation. This process is known as transmitophagy. Mitophagy in yeast was first presumed after the discovery of Yeast Mitochondrial Escape genes (yme), specifically yme1. Yme1 like other genes in the family
Mitophagy
12993722
of bacterial cell production. Cultured flagellates in laboratory experiments demonstrate that they are adapted to predation on bacteria-sized particles and occur in concentrations to control bacterial biomass. Tight fluctuations in numbers of bacteria and flagellates have been found in an eutrophic estuary, particularly in the summer. The amplitude of these fluctuations increases in response to artificial eutrophication with inorganic nutrients and decreases in response to predation. Losses of bacterioplankton by grazing is indirectly related to carbon balances and directly related to prokaryotic inhibitors. A surplus of substrate would cause increased flagellate biomass, increased grazing on bacterioplankton and therefore decreased bacterial
Bacterioplankton
2818658
therapy can be used to prevent infection by targeting adhesion molecules either on the pathogen or on the host cell. Apart from altering the production of adhesion molecules, competitive inhibitors that bind to adhesion molecules to prevent binding between cells can also be used, acting as anti-adhesive agents. Cell adhesion Cell adhesion is the process by which cells interact and attach to neighbouring cells through specialised molecules of the cell surface. This process can occur either through direct contact between cell surfaces or indirect interaction, where cells attach to surrounding extracellular matrix, a gel-like structure containing molecules released by cells
Cell adhesion
4397652
viewed, bacterial cells as well as the surface they are on, are stained dark, while the capsule remains pale or colorless and appears as a ring, or halo, around the cell. The capsule is considered a virulence factor because it enhances the ability of bacteria to cause disease (e.g. prevents phagocytosis). The capsule can protect cells from engulfment by eukaryotic cells, such as macrophages. A capsule-specific antibody may be required for phagocytosis to occur. Capsules also contain water which protects the bacteria against desiccation. They also exclude bacterial viruses and most hydrophobic toxic materials such as detergents. Immunity to one
Bacterial capsule
12967463
single-celled eukaryotes may have evolved from bacterial transformation, or from a similar process in archaea (see below). On the other hand, bacterial conjugation is a type of direct transfer of DNA between two bacteria through an external appendage called the conjugation pilus. Bacterial conjugation is controlled by plasmid genes that are adapted for spreading copies of the plasmid between bacteria. The infrequent integration of a plasmid into a host bacterial chromosome, and the subsequent transfer of a part of the host chromosome to another cell do not appear to be bacterial adaptations. Exposure of hyperthermophilic archaeal Sulfolobus species to DNA
Sexual reproduction
2922011
seasoned, it is popular as a main course and as a dressing in Belgium, where it is known as filet américain ("American fillet"). Food safety of ground meat issues occur because of the possibility of bacterial contamination. Undercooked hamburgers contaminated with were responsible for four deaths and the illness of hundreds of people in the U.S. in 1993. Ground beef must be cooked to 72 °C (160 °F) to ensure all bacterial contamination—whether it be endogenous to the product or contaminated after purchasing by the consumer—is killed. The color of cooked meat does not always indicate the beef has reached
Ground beef
7214802
Jarisch–Herxheimer reaction A Jarisch–Herxheimer reaction () is a reaction to endotoxin-like products released by the death of harmful microorganisms within the body during antibiotic treatment. Efficacious antimicrobial therapy results in lysis (destruction) of bacterial cell membranes, and in the consequent release into the bloodstream of bacterial toxins, resulting in a systemic inflammatory response. Jarisch–Herxheimer reactions are usually not life-threatening. It resembles bacterial sepsis and can occur after initiation of antibacterials, such as mild silver protein, penicillin or tetracycline, for the treatment of louse-borne relapsing fever (80–90% of patients) and in tick-borne relapsing fever (30–40%). It usually manifests within a few
Jarisch–Herxheimer reaction
7214806
syphilis treated with Salvarsan, mercury, or antibiotics. Jarisch thought that the reaction was caused by a toxin released from the dying spirochetes. Jarisch–Herxheimer reaction A Jarisch–Herxheimer reaction () is a reaction to endotoxin-like products released by the death of harmful microorganisms within the body during antibiotic treatment. Efficacious antimicrobial therapy results in lysis (destruction) of bacterial cell membranes, and in the consequent release into the bloodstream of bacterial toxins, resulting in a systemic inflammatory response. Jarisch–Herxheimer reactions are usually not life-threatening. It resembles bacterial sepsis and can occur after initiation of antibacterials, such as mild silver protein, penicillin or tetracycline,
Jarisch–Herxheimer reaction
1683259
Two components of the immune system are particularly affected in AIDS, due to its CD4 T cell dependency: If the patient does not respond to (or does not receive) HIV treatment they will succumb usually to either cancers or infections; the immune system finally reaches a point where it is no longer coordinated or stimulated enough to deal with the disease. Inhibition of CD4 T-cell expansion during HIV infection may occur due to microbial translocation in an IL-10-dependent way. Triggering PD-1 expressed on activated monocytes by its ligand PD-L1, induces IL-10 production which inhibits CD4 T-cell function. T helper cell
T helper cell
8554827
the form of immune complexes. Some APCs expressing comparatively lower levels of lysosomal enzymes are thus less likely to digest the antigen they have captured before presenting it to B cells. Antigen presentation Antigen presentation describes a vital immune process which is essential for T cell immune response triggering. Because T cells recognise only fragmented antigens displayed on cell surfaces, antigen processing must occur before the antigen fragment, now bound to the major histocompatibility complex (MHC), is transported to the surface of the cell, a process known as presentation, where it can be recognized by a T cell receptor. If
Antigen presentation
10528237
transferred to the plant cell but remains within the bacterial cell. Plasmids replicate to produce many plasmid molecules in each host bacterial cell. The number of copies of each plasmid in a bacterial cell is determined by the replication origin. This is the position within the plasmids molecule where DNA replication is initiated. Most binary vectors have a higher number of plasmids copies when they replicate in "E. coli", the plasmid copy-number is usually less when the plasmid is resident within "Agrobacterium tumefaciens". Plasmids can also be replicated in the polymerase chain reaction (PCR). T-DNA contains two types of genes:
Plant transformation vector
15567092
and biological products, human diagnostics, food, and decolonization of bacteria causing nosocomial infections (e.g. MRSA). Protein modifications allow the biotechnological adaption to specific requirements. Affinity magnetic separation Phage-ligand technology The Phage-ligand technology is a technology to detect, bind and remove bacteria and bacterial toxins by using highly specific bacteriophage derived proteins. The host recognition of bacteriophages occur via bacteria-binding proteins that have strong binding affinities to specific protein or carbohydrate structures on the surface of the bacterial host. At the end of the infection life cycle the bacteria-lysing Endolysin is synthesized and degrades the bacterial peptidoglycan cell wall, resulting in
Phage-ligand technology
8893943
and the new RNA molecule to be released. Moving of the transcription bubble in the process may be seen with specialized staining techniques, spectroscopy or microscopy. This process can be seen in live bacterial cells and purified polymerase enzymes. However, in the bacterial cells, topological problems may occur during the process of transcription, but they are resolved by topoisomerase enzymes. Transcription bubble A transcription bubble is a molecular structure that is formed during the transcription of DNA when a limited portion of the DNA double strand is unwound. The Transcription bubble ranges from around 12-14 base pairs, but can be
Transcription bubble
12697194
The facility has fermentation, formulation, vial, freeze drying bacterial facilities classified as Biosafety Level 2 (CDC-NIH BL2-LS) and ISO 9001. The facility includes both the upstream and downstream operations when the fermentation process is scaled up for bacterial polysaccharide product development. The facilities were designed for manufacture of vaccines in compliance with cGMP and European standards. The facility has fermentation, formulations and lyophilization and handling of bacterial polysaccharide products. Utilities include Water-For-Injection Grade Water (WFI) system, oil-free compressed air system (USP), clean steam system, process chilled system and Clean-in-Place systems. Processes include; seed bank, media preparation, fermentation, cell harvest, centrifugation
JN-International Medical Corporation
4147702
bacterial growth, sulfamethoxazole is considered a bacteriostatic antibiotic. Sulfonamides are selective against bacteria because they interfere with the synthesis of folate, a process which does not occur in humans. Humans do not synthesize folate, and must acquire it through diet. Absorption Sulfamethoxazole is well-absorbed when administered topically. It is rapidly absorbed when it is orally administered. Distribution Sulfamethoxazole distributes into most body tissues as well as into sputum, vaginal fluid, and middle ear fluid. It also crosses the placenta. About 70% of the drug is bound to plasma proteins. Its Tmax (or time to reach maximum drug concentration in plasma)
Sulfamethoxazole
2976402
Cell envelope The cell envelope comprises the inner cell membrane and the cell wall of a bacterium. In gram-negative bacteria an outer membrane is also included. This envelope is not present in the Mollicutes where the cell wall is absent. Bacterial cell envelopes fall into two major categories: a gram-positive type and a gram-negative type, distinguished by Gram staining. Either type may have an enclosing capsule of polysaccharide for extra protection. As a group these are known as polysaccharide encapsulated bacteria. As in other organisms, the bacterial cell wall provides structural integrity to the cell. In prokaryotes, the primary function
Cell envelope
16323872
it does not produce any endospores. This is due to its waxy cell wall which retains the malachite green dye even after the decolorizing process. A different type of staining called acid-fast stain will have to be done in order to get further information about this particular type of bacterium. Endospore staining Endospore Staining is a technique used in bacteriology to identify the presence of endospores in a bacterial sample, which can be useful for classifying bacteria. Within bacteria, endospores are protective structures used to survive extreme conditions, but this protective nature makes them difficult to stain using normal techniques
Endospore staining
2899121
M phase, consists of nuclear division (karyokinesis) and cytoplasmic division (cytokinesis), accompanied by the formation of a new cell membrane. This is the physical division of "mother" and "daughter" cells. The M phase has been broken down into several distinct phases, sequentially known as prophase, prometaphase, metaphase, anaphase and telophase leading to cytokinesis. Cell division is more complex in eukaryotes than in other organisms. Prokaryotic cells such as bacterial cells reproduce by binary fission, a process that includes DNA replication, chromosome segregation, and cytokinesis. Eukaryotic cell division either involves mitosis or a more complex process called meiosis. Mitosis and meiosis
Cell growth
3981568
Bacterial oxidation Bacteria biooxidation is an oxidation process caused by microbes where the valuable metal remains (but becomes enriched) in the solid phase.In this process, the metal remains in the solid phase and the liquid can be discarded. Bacterial oxidation is a biohydrometallurgical process developed for pre-cyanidation treatment of refractory gold ores or concentrates. The bacterial culture is a mixed culture of "Acidithiobacillus ferrooxidans", "Acidithiobacillus thiooxidans" and "Leptospirillum ferrooxidans". The bacterial oxidation process comprises contacting refractory sulfide ROM ore or concentrate with a strain of the bacterial culture for a suitable treatment period under an optimum operating environment. The bacteria
Bacterial oxidation