Comparative genomic analysis of the Streptococcus dysgalactiae species group: gene content, molecular adaptation, and promoter evolution.
Comparative genomic analysis of the Streptococcus dysgalactiae species group: gene content, molecular adaptation, and promoter evolution.
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DOI：
10.1093/gbe/evr006
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发表时间：
2011
影响因子：
3.3
通讯作者：
Stanhope MJ
中科院分区：
文献类型：
--
作者：
Suzuki H;Lefébure T;Hubisz MJ;Pavinski Bitar P;Lang P;Siepel A;Stanhope MJ
具有不同致病机理和宿主偏好的密切相关的细菌物种的比较基因组学可以提供鉴定适应性差异的具体细节的手段。停乳链球菌（Streptococcus dysgalactiae，SD）由两个亚种组成：S.停乳亚种equisimilis既是人类的寄生生物又是人类的病原体，S.停乳亚种停乳症是一种动物病原体在这里，我们提出了完整的基因组序列的两个类群，涉及其他物种的链球菌，但专注于适应在SD物种组的分析。我们发现几乎没有证据表明每个SD菌株携带的基因在生化类别中富集，然而，毒力基因库的差异是明显的。一些差异可以归因于原噬菌体和整合接合元件。我们确定了大约9%的非重组核心基因组处于正选择之下，其中一些涉及其他细菌中的已知毒力因子。通过按生化类别、进化枝或分支汇总基因间数据来分析蛋白质组，为几个基因类别以及树的外部分支的进化速率增加提供了证据。启动子主要在纯化选择下进化，但某些类别的基因进化得更快。这些快速进化的类别中有许多与蛋白质的快速进化有关。总体而言，这些结果表明，适应不断变化的环境和新的主机在SD物种组涉及收购的关键毒力基因沿着选择的orthophosphorus蛋白编码位点和操纵子启动子。
Comparative genomics of closely related bacterial species with different pathogenesis and host preference can provide a means of identifying the specifics of adaptive differences. Streptococcus dysgalactiae (SD) is comprised of two subspecies: S. dysgalactiae subsp. equisimilis is both a human commensal organism and a human pathogen, and S. dysgalactiae subsp. dysgalactiae is strictly an animal pathogen. Here, we present complete genome sequences for both taxa, with analyses involving other species of Streptococcus but focusing on adaptation in the SD species group. We found little evidence for enrichment in biochemical categories of genes carried by each SD strain, however, differences in the virulence gene repertoire were apparent. Some of the differences could be ascribed to prophage and integrative conjugative elements. We identified approximately 9% of the nonrecombinant core genome to be under positive selection, some of which involved known virulence factors in other bacteria. Analyses of proteomes by pooling data across genes, by biochemical category, clade, or branch, provided evidence for increased rates of evolution in several gene categories, as well as external branches of the tree. Promoters were primarily evolving under purifying selection but with certain categories of genes evolving faster. Many of these fast-evolving categories were the same as those associated with rapid evolution in proteins. Overall, these results suggest that adaptation to changing environments and new hosts in the SD species group has involved the acquisition of key virulence genes along with selection of orthologous protein-coding loci and operon promoters.
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影响因子：
14.9
作者：
Benson DA;Cavanaugh M;Clark K;Karsch-Mizrachi I;Lipman DJ;Ostell J;Sayers EW
通讯作者：
Sayers EW
影响因子：
14.9
作者：
Davidsen T;Beck E;Ganapathy A;Montgomery R;Zafar N;Yang Q;Madupu R;Goetz P;Galinsky K;White O;Sutton G
通讯作者：
Sutton G
影响因子：
1.5
作者：
Chenier, Sonia;Leclere, Mathilde;Fecteau, Gilles
通讯作者：
Fecteau, Gilles
影响因子：
5.8
作者：
Arakawa, K;Mori, K;Tomita, M
通讯作者：
Tomita, M
影响因子：
3.5
作者：
Bourgoin, F;Pluvinet, A;Guédon, G
通讯作者：
Guédon, G