Taxonomy
Morphology
Cultural characteristics
Biochemical characters
Ecology
Pathogenicity
References
Phylum Firmicutes, Class Bacilli, Order Bacillales, Family Bacillaceae, Genus Bacillus, Bacillus siamensis Sumpavapol, Tongyonk,
Tanasupawat, Chokesajjawatee, Luxananil and Visessanguan 2010.
Description is based on a single isolate.
Gram-positive, motile (peritrichous flagella) rods, 0.3-0.6 x 1.5-3.5 µm. Produce
central / subterminal, ellipsoidal endospores in swollen sporangia.
Colonies are creamy white, mucoid, translucent, raised, entire margins, 3-4 mm in
diameter after 2 days at 37 ºC on TSA; in liquid medium, a thin film is formed at the
surface whilst the rest of the medium is uniformly cloud.
Grows on MacConkey agar, not on bile salt medium.
Aerobic, facultatively anaerobic. Growth temperature 4-55 ºC (optimum 37 ºC), pH
4.5-9 (optimum pH 6-7). Grow in 0-14% NaCl (optimum 0% NaCl).
Isolated from salted crab (poo-khem) in Thailand.
Undetermined.
- Sumpavapol P., Tongyonk L., Tanasupawat S., Chokesajjawatee N., Luxananil P. and Visessanguan W., 2010. Bacillus siamensis
sp. nov., isolated from salted crab (poo-khem) in Thailand. IJSEM 60, 2364-2370.
Positive results for catalase, nitrate reduction, hydrolysis of casein, hydrolysis of starch, Voges-Proskauer, alkaline phosphatase,
esterase, esterase lipase, hydrolysis of esculin, hydrolysis of gelatin, acid production from: L-arabinose, amygdalin, arbutin,
cellobiose, fructose, beta-gentiobiose, D-glucose, glycerol, glycogen, meso-inositol, lactose, maltose, D-mannitol, raffinose, ribose,
sorbitol, salicin, starch, sucrose and D-xylose.
Negative results for degradation of tyrosine, deamination of phenylalanine, beta-galactosidase, hydrolysis of urea, oxidase, indole
production, H2S production, citrate utilization, lipase, hydrolysis of Tween 80, tryptophan deaminase, methyl-red, trypsin, acid
phosphatase, acid production from: adonitol, D-arabinose, D- or L-arabitol, dulcitol, erythritol, D- or L-fucose, galactose, gluconate,
N-acetyl-D-glucosamine, inulin, 2- or 5-ketogluconate, lyxose, D-mannose, melezitose, melibiose, rhamnose, sorbose, trehalose,
xylitol and L-xylose.
(c) Costin Stoica