Ornithinibacillus xuwenensis sp. nov., A Novel Thermotolerant Bacterium Isolated from Mangrove Sediment.

Abstract

A Gram-stain positive, long-rod-shaped, motile, and aerobic bacterial strain, designated 16A2E^T, was isolated from mangrove sediment sample. The 16S rRNA gene sequence similarity analysis indicated that strain 16A2E^T exhibited high similarity to Ornithinibacillus contaminans CCUG 53201^T (98.2%), Ornithinibacillus bavariensis WSBC 24001^T (98.1%), and Ornithinibacillus scapharcae TW25^T (97.7%). Strain 16A2E^T grew within a temperature range of 20-50 °C (optimum 40 °C), a pH range of 6.0-9.0 (optimum pH 8.0), and in the presence of 0-10% (w/v) NaCl (optimum 1%). The genome size of strain 16A2E^T is 3.60 Mbp, with a G + C content of 36.7%. The overall genome related index (OGRI) analyses revealed low average nucleotide identity (ANI < 75.9%), average amino acid identity (AAI < 77.5%), and digital DNA-DNA hybridization (dDDH < 19.8%) with other species in the genus Ornithinibacillus. Chemotaxonomic analyses revealed that the major polar lipids include diphosphatidylglycerol, phosphatidylglycerol, phospholipids, and an aminophospholipid. The predominant fatty acids were iso-C_15:0, anteiso-C_15:0, and anteiso-C_17:0. The sole respiratory quinone was menaquinone-7 (MK-7), and the peptidoglycan amino acid type was determined to be A4β. Based on phenotypic and genotypic analyses, strain 16A2E^T (= GDMCC 1.4379^T = JCM 36753^T) represents a novel species within the genus Ornithinibacillus, for which the name Ornithinibacillus xuwenensis sp. nov. is proposed.