Providencia stuartii (commonly P. stuartii), is a Gram negative bacillus that is commonly found in soil, water, and sewage. P. stuartii is the most common of the 5 species found in the genus Providencia, with Providencia rettgeri, Providencia alcalifaciens, Providencia rustigianii, P heimbachae. Providencia stuartii can be incubated at 37 °C in nutrient agar or nutrient broth. P. stuartii is the genomic source for the restriction endonuclease, PstI. Some other important information about P. stuartii is that it is motile via flagella, non-sporulating, non-lactose fermenting, catalase positive and oxidase negative. It can also grow in anaerobic conditions and on Simmon’s Citrate Agar. Source: Wikipedia (en)