Alcaligenes faecalis

Alcaligenes faecalis is a Gram-negative, rod-shaped, motile, non-nitrate reducing, oxidase positive, catalase positive, beta hemolytic, and citrate positive obligate aerobe that is commonly found in the environment. It was originally named for its first discovery in feces, but was later found to be much more common in other places as well. Optimum growth occurs at about 37°C with no pigmentation. While opportunistic infections do occur, the bacterium is generally considered non-pathogenic. When an opportunistic infection does occur, it is usually observed in the form of a urinary tract infection. The bacterium degrades urea, creating ammonia which increases the pH of the environment. Although A. faecalis is considered to be alkaline tolerant, it maintains a neutral pH in its cytosol to prevent the damaging or denaturing of its charged species and macromolecules.

A. faecalis has been used for the production of non-standard amino acids. A. faecalis is normally found in soil, water, and environments in association with humans.