|Lactobacillus (Limosilactobacillus) gastricus
Phylum Firmicutes, Class Bacilli, Order Lactobacillales, Family Lactobacillaceae, Genus Lactobacillus [Group C lactobacilli
(obligately heterofermentative), Lactobacillus reuteri - phylogenetic group], Lactobacillus gastricus Roos, Engstrand and Jonsson
2005, emend. Endo, Roos, Satoh, Morita and Okada, 2008.
Homotypic synonym: Limosilactobacillus gastricus (Roos et al. 2005) Zheng et al. 2020.
Gram-positive oval or spherical cocci, 0.6-0.8 x 1.0-2.0 µm, occurring as single cells
or in pairs. Tetrad-like cells are uncommon. Nonspore-forming. Nonmotile.
Colonies on MRS agar are 2 mm in diameter, white, smooth & convex, in anaerobic
conditions at 37 ºC for 48 h; growth on MRS agar under aerobic conditions is very
weak. Growth temperature is 25-42 ºC. No growth at 15 or 45 ºC.
Isolated from a biopsy of the healthy human gastric mucosa.
- Hammes W.P. and Hertel C., 2009. Genus I. Lactobacillus Beijerinck 1901. 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,
- Roos S., Engstrand L. and Jonsson H., 2005. Lactobacillus gastricus sp. nov., Lactobacillus antri sp. nov., Lactobacillus
kalixensis sp. nov. and Lactobacillus ultunensis sp. nov., isolated from human stomach mucosa. IJSEM 55, 77-82.
- Endo A., Roos S., Satoh E., Morita H. and Okada S., 2008. Lactobacillus equigenerosi sp. nov., a coccoid species isolated from
faeces of thoroughbred racehorses. IJSEM 58, 914-918.
Obligately heterofermentative (hexoses are fermented to lactic acid, acetic acid (ethanol), and CO2 via the phosphogluconate pathway;
pentoses are fermented to lactic acid and acetic acid by the related pentose phosphate pathaway).
Positive results for esculin hydrolysis, fermentation of: amygdalin, arbutin, cellobiose, fructose, galactose, glucose (with gas
production), gluconate, lactose, maltose, mannose, melibiose, raffinose, salicin, sucrose, and trehalose.
Negative results for catalase, fermentation of: adonitol, D-arabinose, L-arabitol, D-arabitol, dulcitol, erythritol, esculin, glycerol,
glycogen, inositol, inulin, mannitol, melezitose, rhamnose, sorbitol, sorbose, starch, xylose, 2- and 5-ketogluconate.
Variable results for fermentation of: L-arabinose, N-acetylglucosamine, and ribose.
(c) Costin Stoica