coli infections and are caused by uropathogenic E. UTIs are the most common extraintestinal E. Among the intestinal pathogens there are six well-described categories: enteropathogenic E. Three general clinical syndromes can result from infection with one of these pathotypes: enteric/diarrhoeal disease, urinary tract infections (UTIs) and sepsis/meningitis. coli that are capable of causing disease in healthy individuals. Only the most successful combinations of virulence factors have persisted to become specific ' PATHOTYPES' of E. These virulence attributes are frequently encoded on genetic elements that can be mobilized into different strains to create novel combinations of virulence factors, or on genetic elements that might once have been mobile, but have now evolved to become 'locked' into the genome. coli clones that have acquired specific virulence attributes, which confers an increased ability to adapt to new niches and allows them to cause a broad spectrum of disease. However, there are several highly adapted E. coli might exploit its ability to utilize gluconate in the colon more efficiently than other resident species, thereby allowing it to occupy a highly specific metabolic niche 1. One interesting hypothesis suggests that E. coli assures this auspicious symbiosis in the colon are poorly characterized. Despite the enormous body of literature on the genetics and physiology of this species, the mechanisms whereby E. The bacterium is a highly successful competitor at this crowded site, comprising the most abundant facultative anaerobe of the human intestinal microflora. coli is the mucous layer of the mammalian colon. coli strains rarely cause disease except in immunocompromised hosts or where the normal gastrointestinal barriers are breached - as in peritonitis, for example. coli and its human host coexist in good health and with mutual benefit for decades. coli.Įscherichia coli typically colonizes the gastrointestinal tract of human infants within a few hours after birth. coli, and by 'housekeeping' regulators that are present in commensal E. coli are regulated by both pathotype-specific regulators that are absent from commensal E. Genes that encode virulence factors of pathogenic E. Up to 0.53 MB of DNA present in K-12 can also be absent from pathogenic E. coli pathotypes that have been sequenced so far show a striking mosaic pattern, with 2,000 genes present in 247 islands in one pathotype that are not present in K-12. coli are frequently encoded on genetic elements such as plasmids, bacteriophage, transposons and pathogenicity islands that can be mobilized into different strains to create novel combinations of virulence factors. coli can affect a wide range of eukaryotic cellular processes, including cell signalling, ion secretion, protein synthesis, mitosis, cytoskeletal function and mitochondrial function. At least six different pathotypes cause enteric disease, such as diarrhoea or dysentery, and other pathotypes cause extra-intestinal infections, including urinary tract infections and meningitis. In addition to being an important member of the normal intestinal microflora of humans and other mammals, the species Escherichia coli contains many pathotypes that cause a variety of diseases.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |