A New Pneumococcal Serotype, 11E, Has a Variably Inactivated wcjE Gene
A New Pneumococcal Serotype, 11E, Has a Variably Inactivated wcjE Gene
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DOI：
10.1086/653123
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发表时间：
2010-07-01
影响因子：
6.4
通讯作者：
Nahm, Moon H.
中科院分区：
文献类型：
--
作者：
Calix, Juan J.;Nahm, Moon H.
最近，在肺炎链球菌11 A血清型分离株中发现了两种血清学和生物化学上不同的亚型11 A α和11 A β。2种亚型的荚膜多糖合成（cps）位点的序列比较确定了wcjE基因（一种假定的O-乙酰转移酶）的破坏是11 A β表型的遗传标志。在11 A α菌株中，体外wcjE的定向破坏将菌株转换为11 A β表型，证实了该基因在亚型之间的分歧中所起的作用。此外，7个11 A β临床菌株的序列中，每个菌株在wcjE基因中含有不相关的破坏性突变，在肺炎球菌血清型中显示出前所未有的遗传异质性。我们建议将11 A α亚型命名为血清型11 A，将11 A β亚型命名为11 E，这是一种新的血清型。我们的研究结果还表明，肺炎球菌荚膜的多样性比以前认识到的要大得多。
Recently, 2 serologically and biochemically distinct subtypes-11A alpha and 11A beta-were discovered among serotype 11A isolates of Streptococcus pneumoniae. Sequence comparison of the capsular polysaccharide synthesis (cps) loci of the 2 subtypes identified disruption of the wcjE gene, a putative O-acetyltransferase, as the genetic hallmark of the 11A beta phenotype. Directed disruption of wcjE in vitro in an 11A alpha strain switched the strain to the 11A beta phenotype, confirming the role played by the gene in the divergence between the subtypes. Furthermore, sequences from 7 11A beta clinical strains each contained unrelated disruptive mutations in the wcjE gene, displaying an unprecedented degree of genetic heterogeneity in a pneumococcal serotype. We propose to name the 11A alpha subtype as serotype 11A and the 11A beta subtype as 11E, a new serotype. Our findings also suggest that the diversity of pneumococcal capsules is much greater than was previously recognized.