Phylum Firmicutes, Class Bacilli, Order Bacillales, Family Bacillaceae, Genus Bacillus, Bacillus simplex (ex Meyer and Gottheil 1901,
ex Priest, Goodfellow and Todd 1989) Heyman, Logan, Rodriguez-Diaz,Scheldeman, Lebbe, Swings, Heyndrickx and De Vos 2005.
Two biovars may be recognized: Bacillus simplex Biovar 1 and Biovar 2 , differentiate by some sugars fermentation.
Strains of Bacillus carotarum, Bacillus capri, Bacillus cobayae, Bacillus musculi, Bacillus maroccanus, and Bacillus macroides were
proposed to be reclassified as Bacillus simplex.
Gram-variable rods, 0.7-0.9 µm in diameter. Motile. Centrally, paracentrally or subterminally, ellipsoidal, occasionally spherical
endospores in not obviously swollen sporangia.
Colonies are cream, glossy, 3-6 mm in diameter after 2 days, with irregular margins,
slightly raised and umbonate. Grow at pH 7 - 9 and at 20 and 30 ºC but are not able to
grow at 45 ºC. NaCl, allantoin or urate are not required for growth.
Isolated from soil.
- N.A. Logan and P. De Vos, 2009. Genus I. Bacillus Cohn 1872. In: (Eds.) P.D. Vos, G. Garrity, D. Jones, N.R. Krieg, W. Ludwig, F.A.
Rainey, K.-H. Schleifer, W.B. Whitman. Bergey’s Manual of Systematic Bacteriology, Volume 3: The Firmicutes, Springer, 21-127.
- Heyrman J., Logan N.A., Rodriguez-Diaz M., Scheldeman P., Lebbe L., Swings J., Heyndricks M. and DE VOS P., 2005.Study of
mural painting isolates, leading to the transfer of “Bacillus maroccanus” and “Bacillus carotarum” to Bacillus simplex , emended
description of Bacillus simplex, re-examination of the strains previously attributed to “Bacillus macroides” and description of
Bacillus muralis sp.nov. IJSEM 55, 119-131.
Positive results for hydrolysis of hippurate, catalase, nitrate reduction, hydrolysis of
starch, Voges-Proskauer & hydrolysis of Tween 20. Weak positive reaction for acid
production from: L-arabinose (biovar 2), D-glucose, D-mannitol (biovar 2), D-xylose
(biovar 2), N-acetyl-D-glucosamine, fructose, raffinose (biovar 2), ribose (biovar 2),
sorbitol (biovar 2), sucrose & trehalose.
Negative results for arginine dihydrolase beta-galactosidase, lysine decarboxylase,
ornithine decarboxylase, hydrolysis of urea, egg yolk reaction, oxidase, indole, H2S,
acid production from: adonitol, amygdalin, D-arabinose, D-arabitol, L-arabitol, arbutin, cellobiose (biovar 1), dulcitol, erythritol,
D-fucose, L-fucose, galactose, beta-gentibiose, gluconate, glycerol (biovar 1), glycogen, meso-inositol (biovar 1), 2-ketogluconat,
5-ketogluconate, lactose, lyxose, maltose (biovar 1), melezitose, melibiose, D-mannose, methyl beta-xyloside, rhamnose, sorbose,
starch, xylitol, L-xylose, D-xylose (biovar 1).
Variable result for hydrolysis of esculin, hydrolysis of gelatin, hydrolysis of casein, citrate utilization, hydrolysis of Tween 80, acid
production from: L-arabinose (biovar 1), D-mannitol (biovar 1), glycerol (biovar 2), salicin, cellobiose(biovar 2), meso-inositol (biovar
2), maltose (biovar 2), raffinose (biovar 1) & ribose(biovar 1).
(c) Costin Stoica