嗜盐嗜碱菌株20-13的生物学特性及系统发育学分析

对大庆盐碱土中分离到的菌株20-13进行表型特征、生理生化特性和系统发育学研究表明,菌株20-13为革兰氏阴性、能运动的杆菌,末端形成膨大的芽孢,嗜碱且中度嗜盐,能在NaCl浓度为1%~25%(W/V)的改良S-G培养基中生长,最佳生长发生在3%NaC(lW/V);生长的温度范围20~50°C,最适为30~32°C;pH范围8.0~11.0,最适pH 10.0。16S rRNA基因序列的系统进化分析表明,该菌株与厚壁菌门、碱杆菌属Alkalibacillus haloalkaliphilus的成员亲缘关系最近,相似性达99.4%,菌株20-13与Alkalibacillus haloalkaliphilus的表型特征与生理生化特性基本一致。综合分析,确定该菌株与碱杆菌属Alkalibacillus haloalkaliphilus为同一种,且与模式菌株不同的菌株。

Biological characterization and phylogenetic analysis of the halophilic and alkaliphilic strain 20-13

A moderately halophilic and alkaliphilic bacterial strain 20-13 isolated by enrichment culture from a soil sample collected from a soda saline-alkaline soil in Daqing,China.We describe the taxonomic status of the strain 20-13 by phenotypic,physiological,biochemical and phylogenetic analysis.Morphological analysis of the cells of strain 20-13 revealed that they were Gram-negative rods and motility assays confirmed that these cells were motile.Spores are round-terminal.Strain 20-13 was able to grow at 1%-25%(W V) NaCl,with optimum growth at 3%(W V) NaCl.The temperature and pH ranges for growth 20~50 °C and 8.0~11.0,respectively.Optimum growth occurred at 30~32 °C and pH 10.0 in a modified S-G agar medium containing 10%(W V) NaCl.Phylogenetic analysis of 16S rRNA gene sequence showed that strain 20-13 was shown to belong to the genus Alkalibacillus within the phylum Firmicutes and had a close phylogenetic relationship with the specie Alkalibacillus haloalkaliphilus(99.4% sequence similarity).In addition,strain 20-13 was consistent with specie Alkalibacillus haloalkaliphilus basically the same on phenotypic,physiological and biochemical characteristics.In summary,we suggest that strain 20-13 as different strain with the type strain of knows species Alkalibacillus haloalkaliphilus within the genus Halomonas was proposed.