Escherichia coli

Escherichia coli is a species of enterobacteriaceae closely related to Shigella, Salmonella, Klebsiella, Enterobacter, and Citrobacter, including nonvirulent strains making up 0.1% - 1% of the normal human microbiome. Most E. coli strains are harmless or beneficial, but can become pathogenic if they acquire virulence factors in plasmid exchange with virulent coliforms. Pathogenic Escherichia coli include strains responsible for gastroenteritis, urinary tract infection, neonatal meningitis, hemolytic-uremic syndrome, peritonitis, mastitis, gram-negative pneumonia, and sepsis.