Genus Trabulsiella
Cultural characteristics
Biochemical characters
Phylum Proteobacteria, Class Gammaproteobacteria, Order Enterobacterales, Family Enterobacteriaceae, Genus Trabulsiella,
- Trabulsiella guamensis  McWhorter et al. 1992, type species of the genus;
- Trabulsiella odontotermitis Chou et al. 2007.
Gram-negative rods, 0.5-0.7 x 1.0-1.5 μm, nonspore-forming. Motile.
S-type colonies, non-pigmented. Facultatively anaerobic, optimum growth temperature
is 28 ºC (may range from -2 to 45 ºC). Grow very slowly at 4 ºC (1-3 weeks).
Media: Nutrient Agar or Nutrient Broth, Trypticase Soy Agar ± 5% sheep blood.
Trabulsiella guamensis was isolated from dust, soil & human feces (rarely). Resistant to penicillin, ampicillin and cephalothin.
Trabulsiella odontotermitis was isolated from the gut of the termite Odontotermes formosanus.
Unknown pathogenicity. Possible cause of diarrhea in humans.
  1. J. G. Holt et al., 1994. Facultatively Anaerobic Gram-Negative Rods. Subgroup 1. Family Enterobacteriaceae. In: Begey’s Manual of
    Determinative Bacteriology, 9th-edition, Williams & Wilkins, pp 175-189.
  2. McWhorter A.C., Haddock R.L., Nocon F.A., Steigerwalt A.G., Brenner D.J., Aleksic S., Bockemuhl J. & Farmer III (J.J.): Trabulsiella
    guamensis, a new genus and species of the family Enterobacteriaceae that subgroups 4 and 5. J. Clin. Microbiol., 1991, 29, 1480-
  3. Don J. Brenner and J.J. Farmer III, 2001. Family I. Enterobacteriaceae. In:  Bergey’s Manual of Systematic Bacteriology, Second
    edition, Vol two, part B, George M. Garrity (Editor-in-Chief), pp 587-897.
  4. Jui-Hsing Chou, Wen-Ming Chen, A. B. Arun, and Chiu-Chung Young: Trabulsiella odontotermitis sp. nov., isolated from the gut of
    the termite Odontotermes formosanus Shiraki. Int J Syst Evol Microbiol April 2007 57:696-700.
  5. Adeolu M, Alnajar S, Naushad S, S Gupta R. Genome-based phylogeny and taxonomy of the 'Enterobacteriales': proposal for
    Enterobacterales ord. nov. divided into the families Enterobacteriaceae, Erwiniaceae fam. nov., Pectobacteriaceae fam. nov.,
    Yersiniaceae fam. nov., Hafniaceae fam. nov., Morganellaceae fam. nov., and Budviciaceae fam. nov. Int J Syst Evol Microbiol
    2016; 66:5575-5599.
T. guamensis biochemically resembles Salmonella spp. in some tests (H2S positive,
lactose and sacharose negative) and misidentification may occur. Some strains isolated from human feces were indole negative and
might be considered a separated biogroup.

Positive results for catalase, methyl red, citrate utilization (Simmons), H
2S production (TSI), arginine dihydrolase (delayed), lysine
decarboxylase, ornithine decarboxylase, KCN test, esculin hydrolysis, ONPG, tyrosine hydrolysis, acid production from L-arabinose,
cellobiose, esculin, D-galactose, D-mannitol, maltose, mucate, D-mannose, L-rhamnose, D-sorbitol, trehalose and D-xylose.

Negative results for oxidase, Voges–Proskauer test, urea hydrolysis, phenylalanine deaminase, malonate utilization, gelatin
hydrolysis, lipase, DN-ase, acid production from sucrose, dulcitol, adonitol, myo-inositol, raffinose, alpha-methyl-D-glucoside,
erythritol, lactose, melibiose, D-arabitol and salicin.

T. odontotermitis can be differentiated from T. guamensis by negative nitrate reduction, no H2S production and positive Voges-
Proskauer test.
(c) Costin Stoica
Culture media
Biochemical tests
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