Sal.mon.el' la . M.L. ‐ ella dim. ending; M.L. fem. n. Salmonella named after D.E. Salmon, an American bacteriologist. Proteobacteria / Gammaproteobacteria / Enterobacteriales / Enterobacteriaceae / Salmonella Straight rods, 0.7–1.5 × 2.0–5.0 µm, conforming to the general definition of the family Enterobacteriaceae . Gram negative. Usually motile (peritrichous flagella). Facultatively anaerobic. Colonies are generally 2–4 mm in diameter. Nitrates are reduced to nitrites. Gas is usually produced from D ‐glucose . Hydrogen sulfide is usually produced on triple‐sugar iron agar. Indole negative. Citrate is usually utilized as a sole carbon source . Lysine and ornithine decarboxylase (Møller's) reactions are usually positive. Urease negative. Phenylalanine and tryptophan are not oxidatively deaminated. Sucrose, salicin, inositol, and amygdalin are usually not fermented. Lipase and deoxyribonuclease are not produced. Pathogenic for humans, causing enteric fevers, gastroenteritis, and septicemia; may also infect many animal species besides humans. Some serovars are strictly host‐adapted. The mol % G + C of the DNA is : 50–53. Type species : Salmonella choleraesuis (Smith 1894) Weldin 1927, 155 ( Bacillus cholerae suis Smith 1894, 9.)