基于脂肪酸生物标记芽胞杆菌属种类的系统发育

Phylogeny of the genus Bacillus based on fatty acids biomarkers

【目的】测定芽胞杆菌属90个种(亚种)的脂肪酸成分,构建芽胞杆菌属脂肪酸系统发育分类体系。【方法】利用脂肪酸微生物鉴定系统(MIS)分析供试芽胞杆菌种类脂肪酸生物标记,根据脂肪酸生物标记分布特性,选取10种脂肪酸参数即16:0 iso、16:0、17:0 iso、17:0 anteiso、15:0 iso、15:0 anteiso、15:0 iso/15:0anteiso、17:0 iso/17:0 anteiso以及香农指数(H)和均匀度指数(J)构建芽胞杆菌属种类的脂肪酸系统发育分类体系,【结果】从芽胞杆菌属90个种(亚种)共检测到29个脂肪酸生物标记,脂肪酸碳链长度从10到20,前6个相对百分比含量总和最大的脂肪酸是15:0 anteiso、15:0 iso、17:0 anteiso、16:0、17:0 iso和16:0 iso;在测定的90个种(亚种)的脂肪酸组成中,15:0 anteiso和15:0 iso属于高含量完全分布,17:0 anteiso、16:0、17:0 iso和16:0 iso属于中含量不完全分布,其余23个标记属于低含量不完全分布。可将90种(亚种)芽胞杆菌分为5个脂肪酸群,分别为第I群窄温芽胞杆菌脂肪酸群、第II群广温芽胞杆菌脂肪酸群、第III群嗜碱芽胞杆菌脂肪酸群、第IV群嗜酸芽胞杆菌脂肪酸群、第V群嗜温芽胞杆菌脂肪酸群。【结论】芽胞杆菌属的脂肪酸生物标记系统发育分析,可将其划分为5个类群,且各类群的特性与芽胞杆菌的生长特性和生理生化特紧密相关,这是其他分类方法所不具有的,有望成为一种新的分类体系。

[ Object ] The phylogenetic relationship of 90 species of the genus Bacillus was analyzed using fatty acid biomarkers. [ Methods] Fatty acid biomarkers were detected by Microorganism Identification System （Sherlock MIS） with gas chromatography （Agilent 7890 N, MIDI Inc. , Newark, DE）. Based on the distribution characteristics of fatty acid, 10 parameters e.g. 16：0 iso, 16：0, 17：0iso, 17：0 anteiso, 15：0iso, 15：0 anteiso, 15：0 iso/15：0 anteiso, 17：0 iso/ 17：0 anteiso, diversity index （H） and evenness index （J） were constructed to perform fatty acid phylogeny of the genus Bacillus. [ Resultsl In the 90 Bacillus species 29 fatty acid biomarkers were found with the carbon lengths ranging from 10 to 20. From statistical analysis, sum of relative percentage content of the 6 largest fatty acid biomarkers were 15：0 anteiso, 15：0 iso, 17：0 anteiso, 16：0, 17：0 iso and 16：0 iso. Among them, 15：0 anteiso and 15：0 iso possessed high content with fully distribution in all species tested. Of the biomarkers, 17：0 anteiso, 16：0, 17：0 iso and 16：0 iso had middle content, being not fully distributed, and the rest belonged to low content and not fully distributed. Ninety Bacillus species were divided into five fatty acid groups, e.g. stenothermic group, eurithermophile group, alkaliphilic group, acidophilus group and mesophilic group. The cluster analyses of phenetic classification and fatty acid classification were further compared to find that both classification systems yielded an identical result. [ Conclusion ] Phylogenetie classification system of the genus Bacillus using fatty acid biomarkers embraces Bacillus phylogeny with physiological and biochemical charateristics. This fatty acid-based phylogenetic system may become a new system for classification.