of taxonomy, "S. coelicolor A3(2)" belongs to the species S. violaceoruber, and is not a validly described separate species; "S. coelicolor A3(2)" is not to be mistaken for the actual S. coelicolor (Müller), although it is often referred to as S. coelicolor for convenience. The transcriptome and translatome analyses of the strain A3(2) were published in 2016. The first complete genome sequence of S. avermitilis was completed in 2003. Each of these genomes forms a chromosome with a linear structure, unlike most bacterial genomes, which exist in the form of circular chromosomes. The genome sequence of S. scabies, a member of the genus with the ability to cause potato scab disease, has been determined at the Wellcome Trust Sanger Institute. At 10.1 Mbp long and encoding 9,107 provisional genes, it is the largest known Streptomyces genome sequenced, probably due to the large pathogenicity island. Biotechnology In recent years, biotechnology researchers have begun using Streptomyces species for heterologous expression of proteins. Traditionally, Escherichia coli was the species of choice to express eukaryotic genes, since it was well understood and easy to work with. Expression of eukaryotic proteins in E. coli may be problematic. Sometimes, proteins do not fold properly, which may lead to insolubility, deposition in inclusion bodies, and loss of bioactivity of the product. Though E. coli strains have secretion mechanisms, these are of low efficiency and result in secretion into the periplasmic space, whereas secretion by a Gram-positive bacterium such as a Streptomyces species results in secretion directly into the extracellular medium. In addition, Streptomyces species have more efficient secretion mechanisms than E.coli. The properties of the secretion system is an advantage for industrial production of heterologously expressed protein because it simplifies subsequent purification steps and may increase yield. These properties among others make Streptomyces spp. an attractive alternative to other bacteria such as E. coli and Bacillus subtilis. Plant pathogenic bacteria So far, ten species belonging to this genus have been found to be pathogenic to plants: S. scabiei S. acidiscabies S. europaeiscabiei S. luridiscabiei S. niveiscabiei S. puniciscabiei S. reticuliscabiei S. stelliscabiei S. turgidiscabies (scab disease in potatoes) S. ipomoeae (soft rot disease in sweet potatoes) Medicine Streptomyces is the largest antibiotic-producing genus, producing antibacterial, antifungal, and antiparasitic drugs, and also a wide range of other bioactive compounds, such as immunosuppressants. Almost all of the bioactive compounds produced by Streptomyces are initiated during the time coinciding with