1株碱杆菌属菌株的分离和鉴定

Isolation and identification one Alkalibacillus strain

从新疆采集的盐土样品中分离到1株革兰氏阳性、严格好氧、产孢、嗜盐细菌菌株YIM012，对其进行了系统分类学研究．菌株YIM 012为杆菌，生长最适温度为28～45℃，最适pH7．0～8．0，并能在70～250g/L的盐质量浓度中生长良好．其DNA的G＋c的摩尔分数为39％，16SrRNA基因序列分析结果显示，该菌株与碱杆菌属Alkalibacillus salilacus（DSM 16460^T）亲缘关系最近，相似性达到99．6％，但与同属其它2个有效种间相似性低于96％．杂交结果显示其与A．salilacus亲缘关系低于20％，并且在生理生化方面也有差异．综合分析，确定该菌株为碱杆菌属的1个新种，将其命名为嗜盐碱杆菌（Alkalibacillus halophilus）．

A spore-forming, gram positive Bacillus-like, strain YIM 012, was isolated from one hypersaline soil sample collected from Xinjiang Province, China and was subjected to a polyphasic taxonomy study, i ne isolated strain was motile, aerobic and appearing as halophilic in nature, based on its optimum growth condition between 70-250 g/L of NaC1 concentration. The genomic DNA G ＋ C content of the strain was 39 mol %.Phylogenetic analysis based on 16S rRNA gene sequences showed that the closest relative of the strain was Alkalibacillus salilacus（99.6 % ） and the relatedness value of DNA-DNA hybridization was of 20 %. Their physiological and biochemical characterizations were different in many aspects. Therefore, on the basis of polyphasic taxonomic data presented, a novel species of the genus Alkalibacillus, Alkalibacillus halophilus sp. nov, was proposed. The type strain was YIM 012.