通过生理生化实验、16S rDNA 序列分析和同源性杂交,将分离到的XJU-1和XJU-80菌种进行了分类鉴定.XJU-1和XJU-80具有较宽的pH生长范围(分别是pH4.5～12.6和pH3.8～12.6),其G+C mol%含量分别是40.5mol%和42.2mol%.16S rDNA 序列分析和DNA-DNA同源杂交结果表明,XJU-1和XJU-80与Bacillus halodurans C-125和Bacillus halodurans DSM497T具有较高的同源性(99%);两者之间也具有85%的相关性,但其与Bacillus halodurans C-125和Bacillus halodurans DSM497T分别具有81.3%和71.5%的相关性.基于以上结果,将两株分离菌株分类为Bacillus halodurans的两个新品系.%Bacillus halodurans XJU-1 and XJU-80 were characterized in terms of physiological and biochemical characteristics, and 16S rDNA sequence homology and DNA-DNA hybridization analysis. The two isolates can grow in nutrient broth at a broad range of pH values from 4.5 to 12.6 for XJU-1 and from 3.8 to 12.8 for XJU-80, respectively. And the optimum temperature of growth were around 39℃and 42℃, respectively. Phylogenetic analysis of the two strains based on comparison of 16S rRNA sequence revealed that they are closely related to Bacillus halodurans C-125 and DSM497Twith 99% identity. DNA-DNA hybridization showed that the highest levels of DNA-DNA relatedness were found between the two strains (85%) and the B. Halodurans type strains (81.3% and 71.5%), respectively. Moreover, the G+C content of the genomic DNA was 40.5 mol% for XJU-1 and 42.2 mol% for XJU-80.Our results demonstrate that strains XJU-1 and XJU-80 should be classified as two new members of the species B. Halodurans.
展开▼
