PROPERTIES OF THE NEW OBLIGATELY OXALOTROPHIC BACTERIUM BACILLUS-OXALOPHILUS

Bacterial strain using oxalate as the sole carbon and energy source wa s isolated from rhizosphere of sorrel (Rumex acetosa). Cells of the st rain were motile, Gram-positive rods with peritrichous flagella. The i solate formed endospores. Capsules were absent. In addition to oxalate the organism grew on mixtures of formate and glyoxylate, formate and D-glycerate, or methanol and glyoxylate. The strain was a strict aerob e growing at 10 - 40 degrees C and pH 6.8 - 9.0; no growth factors wer e required. Oxalate was oxidized by means of oxalyl-CoA decarboxylase and formate dehydrogenase. Assimilation of oxalate occurred via format ion of tartronic semialdehyde and also via the serine pathway. The Kre bs cycle was disconnected at the level of alpha-ketoglutarate dehydrog enase. The glyoxylate bypass did not function. Ammonium salts were use d as nitrogen sources. G + C content of DNA was 46.7 mole%. The level of DNA homology of the strain studied with typical representatives of the genus Bacillus did not exceed 15%. Based on morphological, biochem ical, and genetic data, we propose to assign the isolated strain to a new species Bacillus oxalophilus sp. nov. A description of the new spe cies is presented.