Paenibacillus thermophilus sp. nov., a novel bacterium isolated from a sediment of hot spring in Fujian province, China

Abstract

A Gram-positive, thermophilic, strictly aerobic bacterium, designated WP-1^T, was isolated from a sediment sample from a hot spring in Fujian province of China and subjected to a polyphasic taxonomic study. Cells of strain WP-1^T were rods (~0.6–0.8 × 2.5–3.5 μm) and motile by means of peritrichous flagella. Endospores were ellipsoidal in terminal or subterminal positions. Strain WP-1^T grew at 37–60 °C (optimum 42–45 °C), 0–3 % NaCl (optimum 1 %, w/v) and pH 3.0–9.0 (optimum pH 6.5–7.0). The predominant menaquinone was MK-7. The major fatty acids were anteiso-C_15:0, iso-C_16:0, C_16:0 and anteiso-C_17:0. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, two glycolipids, two unidentified phospholipids and two unknown polar lipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid (meso-DAP). The G + C content of the genomic DNA was 52.5 %. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain WP-1^T is a member of the genus Paenibacillus and exhibited sequence similarity of 99.3 % to Paenibacillus macerans DSM 24^T and both strains represented a separate lineage from all other Paenibacillus species. However, the level of DNA–DNA relatedness between strain WP-1^T and P. macerans DSM 24^T was 34.0 ± 4.7 %. On the basis of phylogenetic, physiological and chemotaxonomic analysis data, strain WP-1^T is considered to represent as a novel species of the genus Paenibacillus, for which the name Paenibacillus thermophilus sp. nov., is proposed, with the type strain WP-1^T (=DSM 24746^T = JCM 17693^T = CCTCC AB 2011115^T).