蜡样芽孢杆菌群分类地位的基因组学见解。
Genomic insights into the taxonomic status of the Bacillus cereus group.
作者信息
Liu Yang, Lai Qiliang, Göker Markus, Meier-Kolthoff Jan P, Wang Meng, Sun Yamin, Wang Lei, Shao Zongze
机构信息
State Key Laboratory Breeding Base of Marine Genetic Resources; Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, SOA; South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Centre; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources; Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, China.
Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH, Inhoffenstraβe 7B, 38124, Braunschweig, Germany.
出版信息
Sci Rep. 2015 Sep 16;5:14082. doi: 10.1038/srep14082.
The identification and phylogenetic relationships of bacteria within the Bacillus cereus group are controversial. This study aimed at determining the taxonomic affiliations of these strains using the whole-genome sequence-based Genome BLAST Distance Phylogeny (GBDP) approach. The GBDP analysis clearly separated 224 strains into 30 clusters, representing eleven known, partially merged species and accordingly 19-20 putative novel species. Additionally, 16S rRNA gene analysis, a novel variant of multi-locus sequence analysis (nMLSA) and screening of virulence genes were performed. The 16S rRNA gene sequence was not sufficient to differentiate the bacteria within this group due to its high conservation. The nMLSA results were consistent with GBDP. Moreover, a fast typing method was proposed using the pycA gene, and where necessary, the ccpA gene. The pXO plasmids and cry genes were widely distributed, suggesting little correlation with the phylogenetic positions of the host bacteria. This might explain why classifications based on virulence characteristics proved unsatisfactory in the past. In summary, this is the first large-scale and systematic study of the taxonomic status of the bacteria within the B. cereus group using whole-genome sequences, and is likely to contribute to further insights into their pathogenicity, phylogeny and adaptation to diverse environments.
蜡样芽孢杆菌群内细菌的鉴定及其系统发育关系存在争议。本研究旨在使用基于全基因组序列的基因组BLAST距离系统发育(GBDP)方法来确定这些菌株的分类归属。GBDP分析明确地将224株菌株分为30个簇,代表11个已知的、部分合并的物种以及相应的19 - 20个假定的新物种。此外,还进行了16S rRNA基因分析、多位点序列分析的一种新变体(nMLSA)以及毒力基因筛选。由于16S rRNA基因序列高度保守,不足以区分该菌群内的细菌。nMLSA结果与GBDP一致。此外,提出了一种使用pycA基因并在必要时使用ccpA基因的快速分型方法。pXO质粒和cry基因广泛分布,这表明它们与宿主细菌的系统发育位置相关性不大。这可能解释了为什么过去基于毒力特征的分类并不令人满意。总之,这是首次使用全基因组序列对蜡样芽孢杆菌群内细菌的分类地位进行大规模、系统性研究,可能有助于进一步深入了解它们的致病性、系统发育以及对不同环境的适应性。