[Isolation of a large aerobic sporulated sheathed bacteria from soil by elective culture].

Abstract

Eleven endospore-forming strains of a probably unknown species of Bacillus were isolated from samples of pasteurized soil by aerobic enrichment culture at 32 degrees C in a minimal medium containing benzoate, p-hydroxybenzoate or cyclohexane carboxylate, as source of carbon and energy. They grew in the form of unbranched, flexible filaments 1.8 micrograms in diameter and sometimes more than 1,000 micrograms in length. The organism was not coenocytic because transverse partitions were visible. The endospores were oval (1.8 x 2.2 micrograms) and did not deform the filaments. A thin, translucid sheath was present. The 11 strains were prototrophic, used benzoate and acetate as sources of carbon and energy but did not grow in common peptone media. Only the isolation technique has been described here.