Please enable JavaScript.
Coggle requires JavaScript to display documents.
Escherichia coli (Gen Features (Gram-negative, Motile via flagella,…
Escherichia coli
Gen Features
Gram-negative
Motile via flagella
Facultative anaerobe (can grow with or without oxygen
Obtains energy and oxidation and reduction of organic sources
Frequently harmless commensal but some strains are virulent
Virulence factors
Adhesions such as pili and fimbriae that allow attachment to host cells and tissues
some fibril types (e.g. k88 in pigs)
Toxins that act on the gut
Secretion systems that deliver host proteins to alter function/ structure of host cells
Bacterial components that activate innate immunity
Broadly grouped into 2 groups
Inestinal
Diarrheagenic E.coli
e.g. enterohaemorrhagic toxin E.coli
Extra-intestinal
further grouped into pathotypes on the basis of clinical features
Toxins
Enterotoxins important in ETEC
Shiga-like toxins act on blood and
most dangerous
Six-toxins
APEC
Most important endemic disease of broiler and layer chickens in UK
Major cause of mortality in young broilers
2-5% of mortality of chickens in UK
can be both a pathogen and commensal
can cause disease in almost any species
Horizontal gene transfer between bacteria can increase virulence of bacteria
Pathogeniecity islands are regions of DNA acquired into the genome encoding for virulence factors
Mastitis
Particular problem in housed dairy cattle over winter
bacteria infect under and cause inflammation response
E.coli plays role in biosynthesis of vitamin K
E.coli is a ubiquitous in microbes of mammals and birds
Disease is usually the result of virulence working in concert
Summary