Bacillus pasinlerensis sp. nov., a thermophilic bacterium isolated from a hot spring in Turkey

Abstract

A Gram-reaction-positive, endospore-forming bacterium, designated strain P1^T, was isolated from water samples collected from Pasinler Hot Spring and characterized using a polyphasic approach to clarify its taxonomic position. Strain P1^T was found to have chemotaxonomic and morphological characteristics consistent with its classification in the genus Bacillus. The strain shared the highest 16S rRNA gene sequence identity values with Bacillus thermolactis R-6488^T (97.6 %) and Bacillus kokeshiiformis MO-04^T (97.2 %) and formed a distinct clade with both type strains in the phylogenetic trees based on 16S rRNA gene sequences. Strain P1^T could grow optimally at 55 °C and in the presence of 2 % NaCl. The organism was found to contain meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The predominant menaquinone was determined to be MK-7. The major cellular fatty acids were identified as iso-C_{15 : 0}, iso-C_{17 : 0} and anteiso-C_{17 : 0}. Based upon the consensus of phenotypic and phylogenetic analyses, strain P1^T represents a novel species of the genus Bacillus, for which the name Bacillus pasinlerensis sp. nov. is proposed. The type strain is P1^T (=DSM 107529^T=CECT 9885^T=NCCB 100674^T).

Keywords: Bacillus; hot spring; new species; polyphasic taxonomy; thermophilic.