Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Clin Microbiol Infect. 2011 Sep;17(9):1409-14. doi: 10.1111/j.1469-0691.2010.03446.x. Epub 2011 Jan 28.
Streptococcus pneumoniae resides on mucosal surfaces in the nasopharynx, where selection for horizontal transfer of antimicrobial resistance genes and virulence factors may provide a survival advantage. We investigated the distribution of genes for pneumococcal cell surface proteins and their correlations with multilocus sequence typing (MLST), Pneumococcal Molecular Epidemiology Network (PMEN) clones and antimicrobial resistance, to identify pneumococcal virulence factors predicting prevalent clones from 156 pneumococcal isolates recovered from adult patients with community-acquired pneumonia in Japan. Pneumococcal eno, pavA, piuA, cbpA and cbpG were present in all isolates, and hyl and piaA were distributed among the clinical isolates. In contrast, pneumococcal rlrA, pclA, psrP, nanC and pspA family 1-type genes were variably distributed and significantly associated with MLST (Wallace coefficients (W) were over 84%). Serotype was a weaker predictor of sequence type (W, 0.75) than vice versa (W, 0.97). A multiple logistic regression analysis adjusted to the presence of virulence genes, pspA family 1 genes and carriage serotypes revealed that pclA and rlrA correlated with PMEN clones and antimicrobial resistance, and are likely to contribute to the selection of prevalent clones.
肺炎链球菌定植于鼻咽部的黏膜表面，在这些部位，抗生素耐药基因和毒力因子的水平转移可能为其提供生存优势。我们研究了肺炎链球菌细胞表面蛋白基因的分布及其与多位点序列分型（MLST）、肺炎链球菌分子流行病学网络（PMEN）克隆和抗生素耐药性的相关性，以鉴定预测日本成人社区获得性肺炎患者分离的流行克隆的肺炎链球菌毒力因子。156 株肺炎链球菌分离株均携带肺炎链球菌 eno、pavA、piuA、cbpA 和 cbpG 基因，临床分离株中存在 hyl 和 piaA 基因。相反，肺炎链球菌 rlrA、pclA、psrP、nanC 和 pspA 家族 1 型基因的分布存在差异，与 MLST 显著相关（Wallace 系数（W）超过 84%）。血清型是序列型的弱预测因子（W，0.75），而反之则是强预测因子（W，0.97）。对携带毒力基因、pspA 家族 1 基因和携带血清型进行调整的多因素逻辑回归分析表明，pclA 和 rlrA 与 PMEN 克隆和抗生素耐药性相关，可能有助于流行克隆的选择。
