TAXONOMY: cellular organisms -> Bacteria -> Proteobacteria -> Gammaproteobacteria -> Enterobacteriales -> Enterobacteriaceae -> Providencia
Straight rods, 0.6–0.8 × 1.5–2.5 µm, conforming to the general definition of the family Enterobacteriaceae. Gram negative. Motile by peritrichous flagella. They are facultatively anaerobic, chemoorganotrophic, having both a respiratory and a fermentative type metabolism. Optimal growth temperature is 37°C. Oxidatively deaminate phenylalanine and tryptophan. Acid is produced from d-mannose. All except Providencia rustigianii produce acid from one or more of the following polyhydric alcohols: inositol, d-mannitol, adonitol, d-arabitol, and erythritol. Except for Providencia heimbachae all are indole positive. Tartrate (Jordan) is utilized by all but a few strains of P. heimbachae. Simmons citrate is utilized by all species except P. heimbachae and some strains of P. rustigianii. Isolated from diarrhetic stools, urinary tract infections, wounds, burns, bacteremias, and contaminated environmental sources. DNA relatedness tests have shown that Providencia are more closely related to Proteus vulgaris and Proteus mirabilis than to other members of the family Enterobacteriaceae. Although 16S RNA sequence data are not available for the Providencia species, the close relationship of Providencia to Proteus indicates that Providencia, like Proteus, belongs to the Gammaproteobacteria within the family Enterobacteriaceae.
The mol% G + C of the DNA is: 39–42 (Falkow et al., 1962).
Type species: Providencia alcalifaciens
This genus contains microbial species that can reside in the human gastrointestinal tract. [PMC 4262072]