Proteus (bacterium)

Proteus is a genus of Gram-negative Proteobacteria, which includes pathogens responsible for many human urinary tract infections. Proteus species do not usually ferment lactose, but have shown to be capable lactose fermenters depending on the species in a TSI test, Triple Sugar Iron. They are oxidase negative, and urease positive; some species are motile.

Pathogenesis
Three species&mdash;P. vulgaris, P. mirabilis, and P. penneri&mdash;are opportunistic human pathogens.