where does the most metabolic activity in the cell occur
cytosol
84822
Cytosol The cytosol, also known as intracellular fluid (ICF) or cytoplasmic matrix, is the liquid found inside cells. It is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondrion into many compartments. In the eukaryotic cell, the cytosol is surrounded by the cell membrane and is part of the cytoplasm, which also comprises the mitochondria, plastids, and other organelles (but not their internal fluids and structures); the cell nucleus is separate. The cytosol is thus a liquid matrix around the organelles. In prokaryotes, most of the chemical reactions of metabolism take place in the cytosol, while
Cytosol
84845
cell are localized to the cytosol. The most complete data are available in yeast, where metabolic reconstructions indicate that the majority of both metabolic processes and metabolites occur in the cytosol. Major metabolic pathways that occur in the cytosol in animals are protein biosynthesis, the pentose phosphate pathway, glycolysis and gluconeogenesis. The localization of pathways can be different in other organisms, for instance fatty acid synthesis occurs in chloroplasts in plants and in apicoplasts in apicomplexa. Cytosol The cytosol, also known as intracellular fluid (ICF) or cytoplasmic matrix, is the liquid found inside cells. It is separated into compartments by
Cytosol
281057
of the pathway in the given compartment of the cell. For instance, the citric acid cycle, electron transport chain, and oxidative phosphorylation all take place in the mitochondrial membrane. In contrast, glycolysis, pentose phosphate pathway, and fatty acid biosynthesis all occur in the cytosol of a cell. There are two types of metabolic pathways that are characterized by their ability to either synthesize molecules with the utilization of energy (anabolic pathway) or break down of complex molecules by releasing energy in the process (catabolic pathway). The two pathways complement each other in that the energy released from one is used
Metabolic pathway
8898806
prepare for cell death. Recently, researchers have discovered that AIF's activity is dependent upon the type of cell, the apoptotic insult, and its DNA-binding ability. AIF also plays a significant role in the mitochondrial respiratory chain and metabolic redox reactions. The AIF protein is located across 16 exons on the X chromosome in humans. AIF1 (the most abundant type of AIF) is translated in the cytosol and recruited to the mitochondrial membrane and intermembrane space by its N-terminal mitochondrial localization signal (MLS). Inside the mitochondria, AIF folds into its functional configuration with the help of the cofactor flavin adenine dinucleotide
Apoptosis-inducing factor
111881
an inducible high activity from a second enzyme. Enzymes determine what steps occur in these pathways. Without enzymes, metabolism would neither progress through the same steps and could not be regulated to serve the needs of the cell. Most central metabolic pathways are regulated at a few key steps, typically through enzymes whose activity involves the hydrolysis of ATP. Because this reaction releases so much energy, other reactions that are thermodynamically unfavorable can be coupled to ATP hydrolysis, driving the overall series of linked metabolic reactions. There are five main ways that enzyme activity is controlled in the cell. Enzymes
Enzyme
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
12380222
the periphery of the neuron and extends inwards towards the nucleus of the cell. Peripheral chromatolysis has been observed to occur in lithium-induced chromatolysis and it could be useful in investigating and countering the hypothesis that waves of enzymatic activity always progress from the perinuclear area, or the area situated around the nucleus, to the peripheral of the cell. When an axon is injured, the whole neuron reacts to provide increased metabolic activity that is necessary for regeneration of the axon. Part of this reaction includes structural alternations caused by the chromatolysis event. The enlargement of nuclear components due to
Chromatolysis
1349324
Cellular differentiation In developmental biology, cellular differentiation is the process where a cell changes from one cell type to another. Most commonly the cell changes to a more specialized type. Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover. Some differentiation occurs in response to antigen exposure. Differentiation dramatically changes a cell's size, shape, membrane potential, metabolic activity, and
Cellular differentiation
16391991
have been concerned with bacteria. A recent paper (Braissant et al. 2010) provides a general introduction to IMC metabolismic methods in microbiology and an overview of applications in medical and environmental microbiology. The paper also explains how heat flow vs. time data for bacteria in culture are an exact expression—as they occur over time—of the fluctuations in microorganism metabolic activity and replication rates in a given medium (Fig. 6). In general, bacteria are about 1/10 the size of mammalian cells and produce perhaps 1/10 as much metabolic heat-i.e. ca. 3x10 W/cell. Thus, compared to mammalian cells (see above) ca. 10X
Isothermal microcalorimetry
4630376
leaves to mammalian blood flow, dooms attempts to account for motor activity as part of metabolism. This is why metabolic rates are almost always associated with the organism at rest, where metabolic rate is figured by the basal rate for the cell rather than for the rate for the organism in its day-to-day life in the field. West et al. claim that Kleiber's law refers to the basal metabolic rate of an organism's cells, not the field metabolic rate of the organism itself, and regard field metabolic rate to be the product of the average basal metabolic rate and number
Kleiber's law
12251749
monoamines during REM is not allowed to occur, which causes the concentration of neurotransmitters in the brain, that are depleted in clinically depressed persons, to increase. Sleep outside of the REM phase may allow enzymes to repair brain cell damage caused by free radicals. High metabolic activity while awake damages the enzymes themselves preventing efficient repair. This study observed the first evidence of brain damage in rats as a direct result of sleep deprivation. Animal studies suggest that sleep deprivation increases levels of stress hormones, which may reduce new cell production in adult brains. A 1999 study found that sleep
Sleep deprivation
15939379
process of endospore formation has profound morphological and physiological consequences: radical post-replicative remodelling of two progeny cells, accompanied eventually by cessation of metabolic activity in one daughter cell (the spore) and death by lysis of the other (the ‘mother cell’). Although sporulation in" B. subtilis" is induced by starvation, the sporulation developmental program is not initiated immediately when growth slows due to nutrient limitation. A variety of alternative responses can occur, including the activation of flagellar motility to seek new food sources by chemotaxis, the production of antibiotics to destroy competing soil microbes, the secretion of hydrolytic enzymes to scavenge
Sporulation in Bacillus subtilis
2882639
direct various activities within the growing zygote. The DNA of a cell is vulnerable to the damaging effect of oxidative free radicals produced as byproducts of cellular metabolism. DNA damage occurring in oocytes, if not repaired, can be lethal and result in reduced fecundity and loss of potential progeny. Oocytes are substantially larger than the average somatic cell, and thus considerable metabolic activity is necessary for their provisioning. If this metabolic activity were carried out by the oocyte’s own metabolic machinery, the oocyte genome would be exposed to the reactive oxidative by-products generated. Thus it appears that a process evolved
Oocyte
2817668
factor would bind, which prevents the transcription of genes that are transcribed via the activity of that factor. While this does occur, the results are not consistent for all cell types and conditions; there is no generally accepted, general mechanism for transrepression. New mechanisms are being discovered where transcription is repressed, but the activated glucocorticoid receptor is not interacting with DNA, but rather with another transcription factor directly, thus interfering with it, or with other proteins that interfere with the function of other transcription factors. This latter mechanism appears to be the most likely way that activated glucocorticoid receptor interferes
Glucocorticoid
61400
polyphasic system in which all of resolvable cytoplasmic elements of are suspended, including the larger organelles such as the ribosomes, mitochondria, the plant plastids, lipid droplets, and vacuoles. Most cellular activities take place within the cytoplasm, such as many metabolic pathways including glycolysis, and processes such as cell division. The concentrated inner area is called the endoplasm and the outer layer is called the cell cortex or the ectoplasm. Movement of calcium ions in and out of the cytoplasm is a signaling activity for metabolic processes. In plants, movement of the cytoplasm around vacuoles is known as cytoplasmic streaming. The
Cytoplasm
1731830
Interphase Interphase is the phase of the cell cycle in which a typical cell spends most of its life. During this phase, the cell copies its DNA in preparation for mitosis. Interphase is the 'daily living' or metabolic phase of the cell, in which the cell obtains nutrients and metabolizes them, grows, reads its DNA, and conducts other "normal" cell functions. The majority of eukaryotic cells spend most of their time in interphase. This phase was formerly called the resting phase. However, interphase does not describe a cell that is merely resting; rather, the cell is living, and preparing for
Interphase
17073940
influence mTORC1 activity do so through activation or inactivation of the TSC1/TSC2 complex, upstream of mTORC1. mTORC1 interacts at the Ragulator-Rag complex on the surface of the lsyosome in response to amino acid levels in the cell. Even if a cell has the proper energy for protein synthesis, if it does not have the amino acid building blocks for proteins, no protein synthesis will occur. Studies have shown that depriving amino acid levels inhibits mTORC1 signaling to the point where both energy abundance and amino acids are necessary for mTORC1 to function. When amino acids are introduced to a deprived
MTORC1
473715
the amount of cyclin increases, more and more cyclin dependent kinases attach to cyclin signaling the cell further into interphase. The peak of the cyclin attached to the cyclin dependent kinases this system pushes the cell out of interphase and into the M phase, where mitosis, meiosis, and cytokinesis occur. There are three transition checkpoints the cell goes through before entering the M phase. The most important being the G1-S transition checkpoint. If the cell does not pass this phase, then the cell will most likely not go through the rest of the cell division cycle. Prophase is the first
Cell division
956158
succinate overproduction or underconsumption and occurs due to reduced, reverse or completely absent activity of SDH or alternative changes in metabolic state. Mutations in SDH, hypoxia or energetic misbalance are all linked to an alteration of flux through the TCA cycle and succinate accumulation. Upon exiting the mitochondria, succinate serves as a signal of metabolic state, communicating to neighboring cells how metabolically active the originating cell population is. As such, succinate links TCA cycle dysfunction or metabolic changes to cell-cell communication and to oxidative stress-related responses. Succinate requires specific transporters to move through both the mitochondrial and plasma membrane. Succinate
Succinic acid
3937223
are provided with the right kind of nutrition. During batch fermentation, the rate of ethanol production per milligram of cell protein is maximal for a brief period early in this process and declines progressively as ethanol accumulates in the surrounding broth. Studies demonstrate that the removal of this accumulated ethanol does not immediately restore fermentative activity, and they provide evidence that the decline in metabolic rate is due to physiological changes (including possible ethanol damage) rather than to the presence of ethanol. Several potential causes for the decline in fermentative activity have been investigated. Viability remained at or above 90%,
Ethanol fermentation
11306151
heat denaturation prior to the actual PCR, carry-over contamination of PCRs can be controlled effectively if the contaminants contain uracils in place of thymines. Uracil "N"-glycosylase was also used in a study to detect evidence of ongoing low-level metabolic activity and DNA repair in ancient bacteria. Long-term survival of bacteria can occur either through endospore formation (in which the bacterium enters total dormancy, with no metabolic activity at all taking place, and, thus, no DNA repair), or else through reduction of metabolic activity to a very low rate, just sufficient to carry out ongoing DNA repair and prevent the depletion
Uracil-DNA glycosylase
1869423
insulin binding after metformin treatment has also been demonstrated in patients with NIDDM. AMPK probably also plays a role in increased peripheral insulin sensitivity, as metformin administration increases AMPK activity in skeletal muscle. AMPK is known to cause GLUT4 deployment to the plasma membrane, resulting in insulin-independent glucose uptake. Some metabolic actions of metformin do appear to occur by AMPK-independent mechanisms; the metabolic actions of metformin in the heart muscle can occur independent of changes in AMPK activity and may be mediated by p38 MAPK- and PKC-dependent mechanisms. Metformin hydrochloride (1,1-dimethylbiguanide hydrochloride) is freely-soluble in water, slightly soluble in ethanol,
Metformin
10610499
to feed endoparasitically. Nematode feeding on floret primordia induces rapid cell division, cell enlargement, and subsequent cell degeneration and collapse. The continuation of this process results in the formation of a large central cavity (in which the now-sedentary nematodes reside) enveloped by a gall wall. Gall size increases rapidly as nematodes grow and reproduce. The gall wall is several cell layers thick. Inner cells of the gall wall (near the cavity) have dense cytoplasm with several mitochondria, indicating high levels of metabolic activity. These cells most likely provide nutrients to the nematodes. The outer layers of the gall wall are
Anguina agrostis
78021
in combinations during chemical synthesis in order to obtain a desired product. In biochemistry, a consecutive series of chemical reactions (where the product of one reaction is the reactant of the next reaction) form metabolic pathways. These reactions are often catalyzed by protein enzymes. Enzymes increase the rates of biochemical reactions, so that metabolic syntheses and decompositions impossible under ordinary conditions can occur at the temperatures and concentrations present within a cell. The general concept of a chemical reaction has been extended to reactions between entities smaller than atoms, including nuclear reactions, radioactive decays, and reactions between elementary particles, as
Chemical reaction
20450387
incidence of osteoporosis) and low rates of hot flashes, are lost when are combined with castration. However, the risk and severity of gynecomastia with are also greatly diminished in this context. Unlike spironolactone, bicalutamide has no antimineralocorticoid activity, and for this reason, has no risk of hyperkalemia (which can, rarely/in severe cases, result in hospitalization or death) or other antimineralocorticoid side effects such as urinary frequency, dehydration, hypotension, hyponatremia, metabolic acidosis, or decreased renal function that may occur with spironolactone treatment. In women, unlike and spironolactone, bicalutamide does not produce menstrual irregularity or amenorrhea, nor does it interfere with ovulation.
Comparison of bicalutamide with other antiandrogens
281062
reaction is the phosphorylation of fructose-6-phosphate to form the intermediate fructose-1,6-bisphosphate by the enzyme phosphofructokinase accompanied by the hydrolysis of ATP in the pathway of glycolysis. The resulting chemical reaction within the metabolic pathway is highly thermodynamically favorable and, as a result, irreversible in the cell. formula_1 A core set of energy-producing catabolic pathways occur within all living organisms in some form. These pathways transfer the energy released by breakdown of nutrients into ATP and other small molecules used for energy (e.g. GTP, NADPH, FADH). All cells can perform anaerobic respiration by glycolysis. Additionally, most organisms can perform more efficient
Metabolic pathway
12185547
autoimmune attack by the body. Metabolic diseases are usually a result of abnormal functioning of one of the metabolic processes required for regular production and utilization of energy in a cell. This can occur by damaging or disabling an important enzyme, or when a feedback system is abnormally functioning. Toxic diseases are a result of a form of poison that effects neuromuscular junction functioning. Most commonly animal venom or poison, or other toxic substances are the origin of the problem. Neuromuscular junction diseases in this category include snake venom poisoning, botulism, arthropod poisoning, organophosphates and hypermagnesemia.(reference 13) Organophosphates are present
Neuromuscular junction disease
231237
facilitate reactions. Another function is to combine with nitrogen released in the cell, therefore preventing nitrogen overload. α-Ketoglutarate is one of the most important nitrogen transporters in metabolic pathways. The amino groups of amino acids are attached to it (by transamination) and carried to the liver where the urea cycle takes place. α-Ketoglutarate is transaminated, along with glutamine, to form the excitatory neurotransmitter glutamate. Glutamate can then be decarboxylated (requiring vitamin B) into the inhibitory neurotransmitter GABA. It is reported that high ammonia and/or high nitrogen levels may occur with high protein intake, excessive aluminum exposure, Reye's syndrome, cirrhosis, and
Alpha-Ketoglutaric acid
161025
severe skeletal disorder of which achondroplasics could be viewed as carriers. Sickle-cell anemia is also considered a recessive condition, but heterozygous carriers have increased resistance to malaria in early childhood, which could be described as a related dominant condition. When a couple where one partner or both are sufferers or carriers of a single-gene disorder wish to have a child, they can do so through "in vitro" fertilization, which enables preimplantation genetic diagnosis to occur to check whether the embryo has the genetic disorder. Most congenital metabolic disorders known as inborn errors of metabolism result from single-gene defects. Only one
Genetic disorder
17570245
neurotoxins, and reduces adhesion to endothelial cells. The most common treatment is hormone replacement therapy or estrogen therapy. Women using hormone therapy for at least two years have increased blood flow to the hippocampus and temporal lobe as compared to those who did not undergo therapy. These areas of the brain are key to memory. Also, women who do not undergo therapy have been found to have less metabolic activity in the posterior cingulate cortex, while those with estrogen therapy did not show a significant metabolic change. This is important as declines in cerebral metabolism occur in the early stages
Postmenopausal confusion
12371055
into a diverse array of detection methodologies ranging from the sensing of environmental contaminants to the real-time monitoring of pathogen infections in living mice. Nonspecific "lux" bioreporters are typically used for the detection of chemical toxins. They are usually designed to continuously bioluminesce. Upon exposure to a chemical toxin, either the cell dies or its metabolic activity is retarded, leading to a decrease in bioluminescent light levels. Their most familiar application is in the Microtox assay where, following a short exposure to several concentrations of the sample, the decreased bioluminescence can be correlated to relative levels of toxicity. Firefly luciferase
Bioreporter
16555651
and THC exert their immuno-modulating effects via different metabolic pathways. The anti-inflammatory activity of C. sativa extracts was studied on three lines of epithelial cells and on colon tissue in a model of inflammatory bowel diseases (IBDs), where C. sativa flowers were extracted with ethanol, found the anti-inflammatory activity of Cannabis extracts derives from THCA present in fraction 7 (F7) of the extract. However, all fractions of C. sativa at a certain combination of concentrations show a significant increased cytotoxic activity and suppress COX-2 and MMP9 gene expression in both cell culture and colon tissue, suggest the anti-inflammatory activity of
Tetrahydrocannabinolic acid
9014859
of the basal metabolic rate and the physical activity level. This caloric requirement can be met with protein, fat, carbohydrates, alcohol, or a mixture of those. Glucose is the general metabolic fuel, and can be metabolized by any cell. Fructose and some other nutrients can only be metabolized in the liver, where their metabolites transform into either glucose stored as glycogen in the liver and in muscles, or into fatty acids stored in adipose tissue. Because of the blood–brain barrier, getting nutrients to the human brain is especially dependent on molecules that can pass this barrier. The brain itself consumes
Starvation response
91172
oscillator, they are coupled in a manner that requires both to ensure the proper timing of cell cycle events. Other work indicates that phosphorylation, a post-translational modification, of cell cycle transcription factors by Cdk1 may alter the localization or activity of the transcription factors in order to tightly control timing of target genes. While oscillatory transcription plays a key role in the progression of the yeast cell cycle, the CDK-cyclin machinery operates independently in the early embryonic cell cycle. Before the midblastula transition, zygotic transcription does not occur and all needed proteins, such as the B-type cyclins, are translated from
Cell cycle
4656721
reduced almost 1000-fold to near physiological levels. Thus the metabolic, biophysical, recruitment, and signaling roles of PA may be interrelated. As PA is rapidly converted to DAG, it is very short-lived in the cell. This means that it is difficult to measure PA production and therefore to study the role of PA in the cell. However, PLD activity can be measured by the addition of primary alcohols to the cell. PLD then carries out a transphosphatidylation reaction, instead of hydrolysis, producing phosphatidyl alcohols in place of PA. The phosphatidyl alcohols are metabolic dead-ends, and can be readily extracted and measured.
Phosphatidic acid
3712541
Asplenia Asplenia refers to the absence of normal spleen function and is associated with some serious infection risks. Hyposplenism is used to describe reduced ('hypo-') splenic functioning, but not as severely affected as with asplenism. Functional" asplenia occurs when splenic tissue is present but does not work well (e.g. sickle-cell disease, polysplenia) -such patients are managed as if asplenic-, while in anatomic" asplenia, the spleen itself is absent. Acquired asplenia occurs for several reasons: Functional asplenia can occur when patients with metabolic or haematological disorders have their splenic tissue organisation altered. This can lead to results similar to those seen
Asplenia
7238055
cell that do not possess metabolic activity and are not bounded by membranes. The most common inclusions are glycogen, lipid droplets, crystals, and pigments. Volutin granules are cytoplasmic inclusions of complexed inorganic polyphosphate. These granules are called metachromatic granules due to their displaying the metachromatic effect; they appear red or blue when stained with the blue dyes methylene blue or toluidine blue. Gas vacuoles are membrane-bound, spindle-shaped vesicles, found in some planktonic bacteria and "Cyanobacteria", that provides buoyancy to these cells by decreasing their overall cell density. Positive buoyancy is needed to keep the cells in the upper reaches of
Bacterial cell structure
5602935
Metabolic disorder A metabolic disorder can happen when abnormal chemical reactions in the body alter the normal metabolic process. It can also be defined as inherited single gene anomaly, most of which are autosomal recessive. Some of the possible symptoms that can occur with metabolic disorders are lethargy, weight loss, jaundice and seizures. The symptoms expressed would vary with the type of metabolic disorder. There are four categories of symptoms: acute symptoms, late-onset acute symptoms, progressive general symptoms and permanent symptoms. Inherited metabolic disorders are one cause of metabolic disorders, and occur when a defective gene causes an enzyme deficiency.
Metabolic disorder
281056
Metabolic pathway In biochemistry, a metabolic pathway is a linked series of chemical reactions occurring within a cell. The reactants, products, and intermediates of an enzymatic reaction are known as metabolites, which are modified by a sequence of chemical reactions catalyzed by enzymes. In most cases of a metabolic pathway, the product of one enzyme acts as the substrate for the next. However, side products are considered waste and removed from the cell. These enzymes often require dietary minerals, vitamins, and other cofactors to function. Different metabolic pathways function based on the position within a eukaryotic cell and the significance
Metabolic pathway
7110162
be caused by metabolic changes such as endoneurial microvessel disease, which is the degeneration of pericytes due to hyperglycemia, and the reproduction of basement membranes when the pericytes are no longer regulating their cell cycle. The decreased size of the lumen plus the absence of the pericyte, which regulate capillary blood flow and phagocytosis of cellular debris, leads to ischemia. Nerve biopsies have shifted the view toward an immune mechanism that causes Micro Vasculitis, which could eventually lead to ischemia. Experimental treatments using immunosuppressive proteins have provided further corroborative evidence to the immune mechanism theory. Although this disease does occur
Proximal diabetic neuropathy
111891
to be successful, and a few enzymes have now been designed "from scratch" to catalyze reactions that do not occur in nature. General Etymology and history Enzyme structure and mechanism Kinetics and inhibition Enzyme Enzymes are macromolecular biological catalysts. Enzymes accelerate chemical reactions. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is
Enzyme
7855079
damage (see DNA damage (naturally occurring) and Sedelnikova et al.). In humans, about 10,000 oxidative DNA damages occur per cell per day. In the rat, which has a higher metabolic rate than humans, about 100,000 oxidative DNA damages occur per cell per day. In aerobically growing bacteria, ROS appear to be a major source of DNA damage, as indicated by the observation that 89% of spontaneously occurring base substitution mutations are caused by introduction of ROS-induced single-strand damages followed by error-prone replication past these damages. Oxidative DNA damages usually involve only one of the DNA strands at any damaged site,
Cell damage
2719884
does not require APC to be phosphorylated in order to bind, in fact, phosphorylation of Cdh1 by Cdks prevents it from binding to APC from S to M phase. With destruction of M-Cdk, release of CDC20 from the APC amd binding of Cdh1 can now occur, allowing APC activity to continue on during G1 entry. While Cdh1 recognizes M and S cyclins, allowing for their destruction until the entire cell commits to proceed to a new cycle, it does not recognize G1/S cyclins, and during G1/S phase, their cyclin activity can rise unhindered and phosphorylate and thus inactivating Cdh1 and
Anaphase-promoting complex
8581012
condition is unknown. In some cases, close family members may share this condition. In other cases, no other related persons have this condition. The scientific name for the condition is syndactyly, although this term covers both webbed fingers and webbed toes. Syndactyly occurs when apoptosis or programmed cell death during gestation is absent or incomplete. Webbed toes occur most commonly in the following circumstances: It is also associated with a number of rare conditions, notably: Webbed toes in humans are a purely cosmetic condition. This condition does not impair the ability to perform any activity, including walking, running, or swimming.
Webbed toes
9863747
findings. After Shojaei et al. performed experiments testing properties of the 484 strain, aerobic metabolic properties were found. "M. elephantis" is catalase, nitrate reductase, and urease positive as well as weakly acid alcohol fast. The 484 strain was found to be negative for tellurite reduction as well as activity with aryl sulphatase. The optimal growth temperature for this species is about 42° Celsius with its first strains showing at the third day of growth at this temperature. Growth at lower temperatures around 30° Celsius occurs, but growth is minimal over 45° Celsius. Growth of this organism does not occur at
Mycobacterium elephantis
20903307
the transfected cells. As a result, fewer transfected cells survive and more untransfected cells survive. In this case an alternative antibiotic should be considered. The method uses a modified MTT assay. The MTT assay is a colorimetric assay used to assess cell metabolic activity. The assay is based on the reduction of yellow tetrazolium salt (MTT) by active cells to produce purple formazan crystals which accumulate in living cells.Cells are lysed, the crystals are dissolved, and the absorbance of the solution is analysed on a spectrophotometer as a measure of cell viability. In situations where the use of MTT is
Selectivity factor
69190
what are known as altered states of consciousness. Some altered states occur naturally; others can be produced by drugs or brain damage. Altered states can be accompanied by changes in thinking, disturbances in the sense of time, feelings of loss of control, changes in emotional expression, alternations in body image and changes in meaning or significance. The two most widely accepted altered states are sleep and dreaming. Although dream sleep and non-dream sleep appear very similar to an outside observer, each is associated with a distinct pattern of brain activity, metabolic activity, and eye movement; each is also associated with
Consciousness
2861137
the earliest metabolic responses to incoming carbohydrates. It is suspected that these cells are involved in incretin functions. Because insulin is one of, if not the most important, regulators of glucokinase synthesis, diabetes mellitus of all types diminishes glucokinase synthesis and activity by a variety of mechanisms. Glucokinase activity is sensitive to oxidative stress of cells, especially the beta cells. Around 200 mutations of the human glucokinase gene "GCK" have been discovered, that can change the efficiency of glucose binding and phosphorylation, increasing or decreasing the sensitivity of beta cell insulin secretion in response to glucose, and producing clinically significant
Glucokinase
531678
the dormant endospore starting metabolic activity and thus breaking hibernation. It is commonly characterised by rupture or absorption of the spore coat, swelling of the endospore, an increase in metabolic activity, and loss of resistance to environmental stress. Outgrowth follows germination and involves the core of the endospore manufacturing new chemical components and exiting the old spore coat to develop into a fully functional vegetative bacterial cell, which can divide to produce more cells. Endospores possess five times more sulfur than vegetative cells. This excess sulfur is concentrated in spore coats as an amino acid, cysteine. It is believed that
Endospore
9830722
(where the kinase is known as Ipl1) to man. Notably, histone-H3 phosphorylation by Aurora B seems not to be responsible for chromatin condensation. Though Aurora B is enriched at centromeres, it localizes diffusely to all chromatin. In Drosophila cells, Aurora B depletion disrupts chromosome structure and compaction. In these cells, the condensin complex does not localize appropriately to the chromosomes. Similarly, in C. elegans, condensin activity is dependent on Aurora B in metaphase. However, in Xenopus egg cell-free extracts, condensin binding and chromosome condensation occur normally even in the absence of Aurora B. Likewise, after treating cells with an Aurora
Aurora B kinase
8903667
type, and more specifically, with a tissue’s primary metabolic substrate. In pancreatic beta cells, ATP is the primary metabolic source, and the ATP/ADP ratio determines K channel activity. Under resting conditions, the weakly inwardly rectifying K channels in pancreatic beta cells are spontaneously active, allowing potassium ions to flow out of the cell and maintaining a negative resting membrane potential (slightly more positive than the K reversal potential). In the presence of higher glucose metabolism, and consequently increased relative levels of ATP, the K channels close, causing the membrane potential of the cell to depolarize, activating voltage-gated calcium channels, and
ATP-sensitive potassium channel
17098884
(increased T) due to adhesion. 3. Bacteriostatic activity, causing cells to become unable to enter exponential growth even though they are not killed. Transient bacteriostatic activity can cause lag times, increasing T. 4. The metabolic lag phase of bacterial growth. Such a lag phase would be expected to occur in the assay as cells growing slowly or not at all during the initial exposure to antimicrobial peptides in the low-salt buffer are shifted to exponential growth upon addition of twice-concentrated rich media. If this metabolic lag phase increases in the presence of the antimicrobial peptide, it could be considered a
Virtual colony count
20096566
scale, particles can behave as molecules when interacting with a cell which allows them to easily penetrate the cell membrane and interfere in vital molecular pathways if the chemistry is possible. A strong research focus has been placed on triggering production of excessive reactive oxygen species (ROS) using nanoparticles injected into bacterial cells. The presence of excessive ROS can stress the cell structure leading to damaged DNA/RNA, decreased membrane activity, disrupted metabolic activity, and harmful side reactions generating chemicals such as peroxides. ROS production has been induced generally through the introduction of both metal oxide and positively charged metal nanoparticles
Antibiotic properties of nanoparticles
11445586
multicellular organism. Changes in size, shape, metabolic activities, and responsiveness can occur as a result of adjustments in gene expression. Cell diversity and differentiation, in this species, involves decisions made from cell-cell interactions in pathways to either stalk cells or spore cells. These cell fates depend on their environment and pattern formation. Therefore, the organism is an excellent model for studying cell differentiation. Chemotaxis is defined as a passage of an organism toward or away from a chemical stimulus along a chemical concentration gradient. Certain organisms demonstrate chemotaxis when they move toward a supply of nutrients. In "D. discoideum", the
Dictyostelium discoideum
2423035
its stability. ... When an axon of cell "A" is near enough to excite a cell "B" and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that "A"s efficiency, as one of the cells firing "B", is increased. The theory is often summarized as "Cells that fire together wire together." This summary, however, should not be taken too literally. Hebb emphasized that cell "A" needs to "take part in firing" cell "B", and such causality can occur only if cell "A" fires just before, not at
Hebbian theory
9071678
Flux (metabolism) Flux, or metabolic flux is the rate of turnover of molecules through a metabolic pathway. Flux is regulated by the enzymes involved in a pathway. Within cells, regulation of flux is vital for all metabolic pathways to regulate the pathway's activity under different conditions. Flux is therefore of great interest in metabolic network modelling, where it is analysed via flux balance analysis. In this manner, flux is the movement of matter through metabolic networks that are connected by metabolites and cofactors, and is therefore a way of describing the activity of the metabolic network as a whole using
Flux (metabolism)
17487514
Wade–Giles table This Wade–Giles table is a complete listing of all Wade–Giles syllables used in Standard Chinese. Each syllable in a cell is composed of an initial (columns) and a final (rows). An empty cell indicates that the corresponding syllable does not exist in Standard Chinese. The below table indicates possible combinations of initials and finals in Standard Chinese, but does not indicate tones, which are equally important to the proper pronunciation of Chinese. Although some initial-final combinations occur with each of the five different tones, most do not. Some only occur with one tone. Finals are grouped into subsets
Wade–Giles table
21009172
cells are working together and activation one another to aid in wound repair. Time-lapse microscopy enabled detection of propagating pulsatile ERK activity as waves emanating from cell of initial activation to adjacent cells, supporting the conclusion that these wave dynamics occur both "in vitro" and "in vivo". In wound healing, epithelial cell movements occur by cell sheet coordinated migration as a unit. Wounds induce ERK activity signal waves that propagates across the cell sheet during migration, causing force generation. Lesions in the epidermis initiate many wave-like signal cascades, one of which is ERK activation signaling. Injury to the skin induces
Spatial propagation of radial ERK distribution
21009166
activity - as cell density increases, basal ERK activity steadily decreases. However, cell density and pulse frequency are graphing ERK activity pulse frequency as a function of cell density gives a bell-shaped plot, with peak frequency at intermediate cell density, where the majority of cells are in contact with one or two other cells. Intermediate cell density shows propagation of signals in a radially distributing-like manner (lower and higher cell density did not exhibit this behavior). This density also correlates with peak cell proliferation observed. At low cellular density, where most cells are in little to zero contact with another
Spatial propagation of radial ERK distribution
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
9120473
Metabolic bone disease Metabolic bone disease is an umbrella term referring to abnormalities of bones caused by a broad spectrum of disorders. Most commonly these disorders are caused by abnormalities of minerals such as calcium, phosphorus, magnesium or vitamin D leading to dramatic clinical disorders that are commonly reversible once the underlying defect has been treated. These disorders are to be differentiated from a larger group of genetic bone disorders where there is a defect in a specific signaling system or cell type that causes the bone disorder. There may be overlap. For example, genetic or hereditary hypophosphatemia may cause
Metabolic bone disease
3456853
operations involved in the cell cycle occur in the proper temporal order. In "Caulobacter", this is accomplished by the genetic regulatory circuit composed of five master regulators and an associated phospho-signaling network. The phosphosignaling network monitors the state of progression of the cell cycle and plays an essential role in accomplishing asymmetric cell division. The cell cycle control system manages the time and place of the initiation of chromosome replication and cytokinesis as well as the development of polar organelles. Underlying all these operations are the mechanisms for production of protein and structural components and energy production. The “housekeeping” metabolic
Caulobacter crescentus
9356543
and other stressors. In order for viruses to replicate within a host cell and for bacteria to carry out the metabolic processes needed to grow and divide, they must first take in necessary nutrients and transcription factors from their surroundings. Even if a virus is able to bind to a host cell and transfer its genetic material through the cell membrane, the cell may not contain the necessary polymerases and enzymes necessary for viral replication to occur and for pathogenesis to continue. Many pathogens also contain important virulence factors within their genomes. In particular, pathogenic bacteria are capable of translating
Host tropism
12461890
Spermatocytic seminoma Spermatocytic seminoma is a neoplasm of the testis ("i.e." a tumour of the testis), and classified as a germ cell tumour. The name of the tumour comes from the similarity (under the microscope) between the small cells of the tumour and secondary spermatocytes. Spermatocytic seminoma is not considered a subtype of seminoma and, unlike seminoma and most other germ cell tumours, it does not arise from "intratubular germ cell neoplasia". It has not been described as arising in locations outside the testis, and does not occur in association with other germ cell tumours. The new WHO classification, due
Spermatocytic seminoma
5687272
debilitating organ damage (particularly the liver, kidneys, heart, and brain), and even death, have been known to occur. Ethanol, morphine, paracetamol (acetaminophen), cyclooxygenase inhibitors (NSAIDs), endogenous steroids, and certain benzodiazepines are all capable of contributing to GCA depletion, with ethanol and acetaminophen being the most commonly implicated substances involved in cases of accidental overdoses which have been positively attributed to glucuronic acid depletion. Excessive quantities of GCA can also be hazardous to health, tobacco smoke, most barbiturates, and some carbamates are known to actually stimulate GCA production. Increased GCA activity results in a decrease of the concentration and metabolic half-life
Glucuronic acid
4909342
of protein synthesis. Only in postmitotic cells (i.e. cells in early G) did serum withdrawal force cells into quiescence (G). In fact, Zetterberg found that virtually all of the variability in cell cycle length can be accounted for in the time it takes the cell to move from the restriction point to S phase. Except for early embryonic development, most cells in multicellular organisms persist in a quiescent state known as G, where proliferation does not occur, and cells are typically terminally differentiated; other specialized cells continue to divide into adulthood. For both of these groups of cells, a decision
Restriction point
9600809
will see later how multiple, parallel buffer lines can be determined for a given system). One of the most important features of the Davenport Diagram is its usefulness in depicting movement from one point on the equilibrium surface to another following changes in respiration and/or metabolism. Four fundamental changes may occur that affect acid-base balance in the body: respiratory acidosis, respiratory alkalosis, metabolic acidosis and metabolic alkalosis. Additionally, a respiratory and a metabolic disturbance may occur simultaneously, such as respiratory acidosis followed by a compensatory shift towards metabolic alkalosis. To understand how changes in respiration might affect blood pH, consider
Davenport diagram
7771297
strengthens the synapse if there was sufficient activity in both the presynaptic and postsynaptic cells. If the postsynaptic cell does not become sufficiently depolarized then there is no coincidence detection and LTP/LTD do not occur. LTD, or long-term depression, works the same way however it focuses on a lack of depolarization coincidence. LTD can be induced by electrical impulses at around 5 Hz. These changes are synapse specific. A neuron can have many different synapses all controlled via the same mechanisms defined here. The earliest proposed mechanism for plastic activity is based around glutamate receptors and their ability to change
Metaplasticity
5495921
and proteins into the oocyte via ring canals. Due to their high metabolic activity, nurse cells likely experience the DNA damaging effect of oxidative free radicals produced as a byproduct of this metabolism. This damaging effect would otherwise befall the DNA of the egg cells if they were responsible for their own synthesis. The many genome copies in each nurse cell may provide redundancy of genetic information that would allow the nurse cell to carry out its provisioning function even in the face of considerable oxidative DNA damage. Nurse cell In general biology or reproductive physiology the term nurse cell
Nurse cell
1995465
subunit. This cleavage allows the active-site loops to take up a conformation favourable for enzymatic activity. "Cleavage of Initiator and Executioner caspases" occur by different methods outlined in the table below. Apoptosis is a form of programmed cell death where the cell undergoes morphological changes, to minimize its effect on surrounding cells to avoid inducing an immune response. The cell shrinks and condenses - the cytoskeleton will collapse, the nuclear envelope disassembles and the DNA fragments up. This results in the cell forming self-enclosed bodies called 'blebs', to avoid release of cellular components into the extracellular medium. Additionally, the cell
Caspase
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
2340488
one of various forms of dormancy where the thermoregulation process temporarily allows the body temperature to drop, thereby conserving energy. Examples include hibernating bears and torpor in bats. Thermoregulation in organisms runs along a spectrum from endothermy to ectothermy. Endotherms create most of their heat via metabolic processes, and are colloquially referred to as warm-blooded. When the surrounding temperatures are cold, endotherms increase metabolic heat production to keep their body temperature constant, thus making the internal body temperature of an endotherm more or less independent of the temperature of the environment. One metabolic activity, in terms of generating heat, that
Thermoregulation
10551055
is demonstrated by noticeable changes both in blood circulating cells and haemopoietic cells (these are cells involved in all blood cell production, stem cells found in bone marrow). There are other decreases seen in these cells, and these include enzymatic activity. Because it is necessary for some supplementation of this, the liver increases in activity during this period. It is as if there is a shift in responsibility from the haemopoietic cells to the liver. There is a high correlation between increased activity of the liver and decreased myelopoietic activity. Decrease in metabolic activity could be due to the low
Italian crested newt
17704829
weight and surface charge (both being generation-dependent) increases their cytotoxic behavior. Initial studies on PAMAM toxicity showed that PAMAM was less toxic (in some cases, much less so) than related dendrimers, exhibiting minimal cytotoxicity across multiple toxicity screens, including tests of metabolic activity (MTT assay), cell breakdown (LDH assay), and nucleus morphology (DAPI staining). However, in other cell lines, the MTT assay and several other assays revealed some cytotoxicity. These disparate observations could be due to differences in sensitivity of the various cell lines used in each study to PAMAM; although cytotoxicity for PAMAM varies among cell lines, they remain
Poly(amidoamine)
4748164
Hypermetabolism Hypermetabolism is the physiological state of increased rate of metabolic activity and is characterized by an abnormal increase in the body’s basal metabolic rate. Hypermetabolism is accompanied by a variety of internal and external symptoms, most notably extreme weight loss, and can also be a symptom in itself. This state of increased metabolic activity can signal underlying issues, especially hyperthyroidism or fatal familial insomnia. The drastic impact of the hypermetabolic state on patient nutritional requirements is often understated or overlooked as well. Hypermetabolism typically occurs after significant injury to the body. In hospitals and institutions, the most common causes
Hypermetabolism
111843
Enzyme Enzymes are macromolecular biological catalysts. Enzymes accelerate chemical reactions. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called "enzymology" and a new field of pseudoenzyme analysis has recently grown up, recognising that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in
Enzyme
4268325
cell membrane from expansion induced damage, the plant cell changes the proportions of almost all lipids in the cell membrane, and increases the amount of total soluble protein and other cryoprotecting molecules, like sugar and proline. Chilling injury occurs at 0–10 degrees Celsius, as a result of membrane damage, metabolic changes, and toxic buildup. Symptoms include wilting, water soaking, necrosis, chlorosis, ion leakage, and decreased growth. Freezing injury may occur at temperatures below 0 degrees Celsius. Symptoms of extracellular freezing include structural damage, dehydration, and necrosis. If intracellular freezing occurs, it will lead to death. Freezing injury is a result
Cold hardening
3254749
from deficiency (salt-wasting) in early infancy to excess (hypertension) in childhood and adult life. Salt-wasting in early infancy does not occur in most cases of 11β-OH CAH but can occur because of impaired production of aldosterone aggravated by inefficiency of salt conservation in early infancy. When it occurs it resembles the salt-wasting of severe 21-hydroxylase deficient CAH: poor weight gain and vomiting in the first weeks of life progress and culminate in life-threatening dehydration, hyponatremia, hyperkalemia, and metabolic acidosis in the first month. Despite the inefficient production of aldosterone, the more characteristic mineralocorticoid effect of 11β-OH CAH is hypertension. Progressive
Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency
4352795
breathing called Kussmaul respirations which is classically associated with diabetic ketoacidosis. Rapid deep breaths increase the amount of carbon dioxide exhaled, thus lowering the serum carbon dioxide levels, resulting in some degree of compensation. Overcompensation via respiratory alkalosis to form an alkalemia does not occur. Extreme acidemia leads to neurological and cardiac complications: Physical examination occasionally reveals signs of disease, but is otherwise normal. Cranial nerve abnormalities are reported in ethylene glycol poisoning, and retinal edema can be a sign of methanol intoxication. Longstanding chronic metabolic acidosis leads to osteoporosis and can cause fractures. Metabolic acidosis occurs when the body
Metabolic acidosis
2758575
affect pyruvate kinase through the inhibition of gluconeogenesis. Specifically, the addition of metformin is linked to a marked decrease in glucose flux and increase in lactate/pyruvate flux from various metabolic pathways. Although metformin does not directly affect pyruvate kinase activity, it causes a decrease in the concentration of ATP. Due to the allosteric inhibitory effects of ATP on pyruvate kinase, a decrease in ATP results in diminished inhibition and the subsequent stimulation of pyruvate kinase. Consequently, the increase in pyruvate kinase activity directs metabolic flux through glycolysis rather than gluconeogenesis. Genetic defects of this enzyme cause the disease known as
Pyruvate kinase
4702693
how easy it is to modify the pathway of the organism. "Escherichia coli" ("E. coli") is widely used in metabolic engineering to synthesize a wide variety of products such as amino acids because it is relatively easy to maintain and modify. If the organism does not contain the complete pathway for the desired product or result, then genes that produce the missing enzymes must be incorporated into the organism. The completed metabolic pathway is modeled mathematically to find the theoretical yield of the product or the reaction fluxes in the cell. A flux is the rate at which a given
Metabolic engineering
21009161
signal firing is seen in the induced, and time delayed, ERK activity propagation patterns, all of which require MPP-mediated cleavage of pro-EFGR ligands. ERK activity pulses occur then from either stochastic, non-ordered, firing or from lateral propagation of ERK activity signal from adjacent cell. Lateral propagation of these signals is distributed radially; cross-correlation analyses indicate a delay of 3–6 minutes for the time course of ERK activity signal-waves distribution. Importantly, in SPREAD, activation of ERK in the cell receiving propagated signal is always transient regardless of the duration and intensity of the ERK activity in the propagating cell. ERK is
Spatial propagation of radial ERK distribution
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
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
935206
a variety of adverse developments such as arterial microinjuries and clot formation (i.e. heart disease) and exaggerated cell division (i.e. cancer). Hyperinsulinemia and insulin resistance (the so-called metabolic syndrome) are characterized by a combination of abdominal obesity, elevated blood sugar, elevated blood pressure, elevated blood triglycerides, and reduced HDL cholesterol. Obesity can unfavourably alter hormonal and metabolic status via resistance to the hormone leptin, and a vicious cycle may occur in which insulin/leptin resistance and obesity aggravate one another. The vicious cycle is putatively fuelled by continuously high insulin/leptin stimulation and fat storage, as a result of high intake of
Human nutrition
2899130
is usually more significant. It can be measured by manual counting of cells under microscopy observation, using the dye exclusion method (i.e. trypan blue) to count only viable cells. Less fastidious, scalable, methods include the use of cytometers, while flow cytometry allows combining cell counts ('events') with other specific parameters: fluorescent probes for membranes, cytoplasm or nuclei allow distinguishing dead/viable cells, cell types, cell differentiation, expression of a biomarker such as Ki67. Beside the increasing number of cells, one can be assessed regarding the metabolic activity growth, that is, the CFDA and calcein-AM measure (fluorimetrically) not only the membrane functionality
Cell growth
2341406
Mg may return to the roots in the phloem sap. When a Mg ion has been absorbed by a cell requiring it for metabolic processes, it is generally assumed that the ion stays in that cell for as long as the cell is active. In vascular cells, this is not always the case; in times of plenty, Mg is stored in the vacuole, takes no part in the day-to-day metabolic processes of the cell (Stelzer "et al.", 1990), and is released at need. But for most cells it is death by senescence or injury that releases Mg and many of
Magnesium in biology
175330
systems that are causally or independently evolving over genes. Research into modes and mechanisms of epigenetic inheritance is still in its scientific infancy, however, this area of research has attracted much recent activity as it broadens the scope of heritability and evolutionary biology in general. DNA methylation marking chromatin, self-sustaining metabolic loops, gene silencing by RNA interference, and the three dimensional conformation of proteins (such as prions) are areas where epigenetic inheritance systems have been discovered at the organismic level. Heritability may also occur at even larger scales. For example, ecological inheritance through the process of niche construction is defined
Heredity
2897688
> one gram, where W is the organization of all of the BMRs of the organism's structure, but also includes the activity of the structure, as ME increases over 25%, MR/MPLS increases rather than decreases, as it does for BMR. An MR made up of an organization of BMRs will be referred to as an FMR. As ME decreases below 25%, FMR diminishes rather than increases as it does for BMR. The antagonism between FMR and BMR is what marks the process of aging of biomass W in energetic terms. The ME for the organism is the same as that
Basal metabolic rate
19755197
to the early up regulation of cell adhesion proteins such as fibronectin and tenascin in the fetus. During early gestation in the fetal wounds of rabbits, the production of fibronectin occurs around 4 hours after wounding, much faster than in adult wounds where expression of fibronectin does not occur until 12 hours post wounding. The same pattern can be seen in the deposition of tenascin. It is this ability of the fetal fibroblast to quickly express and deposit fibronectin and tenascin, which ultimately allows cell migration and attachment to occur, resulting in an organised matrix with less scarring. Another major
Scar free healing
20571653
flora. The lamina propria of connective tissue is under the epithelium. The basal layer of the epithelium is the most mitotically active and reproduces new cells. This layer is composed of one layer of cuboidal cells laying on top of the basal membrane. The parabasal cells include the stratum granulousum and the stratum spinosum. In these two layers, cells from the lower basal layer transition from active metabolic activity to death (apoptosis). In these mid-layers of the epithelia, the cells begin to lose their mitochondria and other cell organelles. The multiple layers of parabasal cells are polyhedral in shape with
Vaginal epithelium
7983255
pathogen's survival is absent or very different in humans. In the example above, humans do not make peptidoglycan, therefore inhibitors of this process are selectively toxic to bacteria. Selective toxicity is also produced in antibiotics by exploiting differences in the structure of the ribosomes in bacteria, or how they make fatty acids. Enzyme inhibitors are also important in metabolic control. Many metabolic pathways in the cell are inhibited by metabolites that control enzyme activity through allosteric regulation or substrate inhibition. A good example is the allosteric regulation of the glycolytic pathway. This catabolic pathway consumes glucose and produces ATP, NADH
Enzyme inhibitor
111880
Different enzymes digest different food substances. In ruminants, which have herbivorous diets, microorganisms in the gut produce another enzyme, cellulase, to break down the cellulose cell walls of plant fiber. Several enzymes can work together in a specific order, creating metabolic pathways. In a metabolic pathway, one enzyme takes the product of another enzyme as a substrate. After the catalytic reaction, the product is then passed on to another enzyme. Sometimes more than one enzyme can catalyze the same reaction in parallel; this can allow more complex regulation: with, for example, a low constant activity provided by one enzyme but
Enzyme
8074665
up microbial fermentations is the stability of the microbial strain: the engineered microorganism will attempt to mutate or shed the metabolic pathway, in part because intermediates in the metabolic pathway accumulate and are toxic to the cells. To balance pathway flux and reduce the cost of producing a desired biofuel, Keasling’s laboratory developed dynamic regulators to sense the levels of intermediates in the pathway and regulate pathway activity. These regulators stabilized the pathway and the cell and improved biofuel yields making it possible to grow the engineered cells in large-scale fermentation tanks for fuel production. Many of the best fuels
Jay Keasling
15451482
responsible for expressing the mitogenic and metabolic actions of Insulin, respectively. The activation of MAP-Kinase leads to completion of mitogenic functions like cell growth and gene expression. The activation of PI-3K leads to crucial metabolic functions such as synthesis of lipids, proteins and glycogen. It also leads to cell survival and cell proliferation. Most importantly, the PI-3K pathway is responsible for the distribution of glucose for important cell functions.The activation of PI-3K leads to the activation of PKB (AKT) that induces the impact of insulin on the liver. For example, the suppression of hepatic glucose synthesis and the activation glycogen
Insulin signal transduction pathway
4630377
of cells in the organism. Biologists point out that BMR cannot possibly account for motor activity even by this reckoning, and the equation is therefore of limited value either way. That metabolic efficiency should deviate from the favored high values is not part of the current debate, even though it creates inconsistencies within standard models, especially with regard to the nature of aging and the nature of the metabolic relation between the cell and the organism's mass. The standard versions of the equation's exponent (those that do not consider ME) cannot account for the wide variation in the lifetimes between
Kleiber's law
11388826
another. PTPrho does not bind to other subfamily members to mediate cell-cell aggregation, similar to other type R2B subfamily members. The MAM domain, Ig domain and all four fibronectin III domain of PTPrho are necessary for cell-cell aggregation. PTPrho is the most frequently mutated RPTP in colon, lung, skin and stomach cancers. Many of the mutations observed in cancer occur in the extracellular domain of PTPrho, suggesting that defective cell-cell aggregation may contribute to the tumorigenicity of these mutations. When PTPrho proteins are engineered with the different point mutations observed in cancer and then are expressed in non-adherent Sf9 cells,
PTPRT
20879855
Calcium cycle The calcium cycle allows for the transition of calcium between its soluble and insoluble forms, thus allowing the continual movement of calcium between living organisms and the earth. Calcium present within sedimentary rock can be released into both the soil and ocean. Here it can be used by marine and terrestrial plants and animals. Plants require calcium for both cell wall structure and promoting enzyme activity, which coordinates growth processes"." These calcium containing plants are then consumed by marine and terrestrial animals where it can be stored and used to form bone and enable cellular processes. This metabolic
Calcium cycle
2713183
and sedatives), and brain tumors can cause this acidemia. Pneumothorax, emphysema, chronic bronchitis, asthma, severe pneumonia, and aspiration are among the most frequent causes. It can also occur as a compensatory response to chronic metabolic alkalosis. One key to distinguish between respiratory and metabolic acidosis is that in respiratory acidosis, the CO is increased while the bicarbonate is either normal (uncompensated) or increased (compensated). Compensation occurs if respiratory acidosis is present, and a chronic phase is entered with partial buffering of the acidosis through renal bicarbonate retention. However, in cases where chronic illnesses that compromise pulmonary function persist, such as
Acidosis
4600732
is illustrated by the pathologies resulting from their mutation. Thomsen’s disease, Dent’s disease, infantile malignant osteopetrosis, and Bartter’s syndrome are all genetic disorders due to such mutations. At least one role of the cytoplasmic CBS domains regards regulation via adenosine nucleotides. Particular CLC transporters and proteins have modulated activity when bound with ATP, ADP, AMP, or adenosine at the CBS domains. The specific effect is unique to each protein, but the implication is that certain CLC transporters and proteins are sensitive to the metabolic state of the cell. The S acts as the primary selectivity filter for most CLC proteins,
Chloride channel
7983264
molecule of ricin to kill a cell. Enzyme inhibitor An enzyme inhibitor is a molecule that binds to an enzyme and decreases its activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used in pesticides. Not all molecules that bind to enzymes are inhibitors; "enzyme activators" bind to enzymes and increase their enzymatic activity, while enzyme substrates bind and are converted to products in the normal catalytic cycle of the enzyme. The binding of an inhibitor can stop a substrate from entering the enzyme's active site
Enzyme inhibitor