Limited diversity of Streptococcus pneumoniae psaA among pneumococcal vaccine serotypes
Limited diversity of Streptococcus pneumoniae psaA among pneumococcal vaccine serotypes
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肺炎球菌疫苗血清型中肺炎链球菌 psaA 的多样性有限
DOI：
10.1128/iai.65.5.1967-1971.1997
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发表时间：
1997
影响因子：
3.1
通讯作者：
Andgeorge M. Carlone
中科院分区：
文献类型：
--
作者：
J. Sampson;Zabrina Furlow;Anne M. Whitney;Derrick B. Williams;R. Facklam;Andgeorge M. Carlone
肺炎球菌表面粘附素A(PsaA)是革兰氏阳性菌肺炎链球菌的一种表面暴露蛋白。它属于一组被称为脂蛋白受体I抗原家族的蛋白质。从肺炎球菌6B型包膜株中克隆了编码psaA的基因，并进行了序列测定。将该多肽序列与肺炎链球菌2型、绿色链球菌和粪肠球菌中发现的同源物进行比较。推导的多肽之间的同源性在57%到98%之间。应用聚合酶链式反应-限制性片段长度多态性分析方法，对23个微囊化疫苗血清型进行了psaA基因的多态性分析。用10种不同的酶分析了代表23价多糖疫苗中23个血清型的80个菌株。这一分析表明，该基因内的限制酶切位点是高度保守的，只有10%的菌株发生了微小的变异，这是额外的Tsp509I位点的结果。在这里检查的基因内的其他限制位点缺乏变异表明psaA在遗传上是保守的，这是候选共同蛋白疫苗所必需的重要特征。
The pneumococcal surface adhesin A (PsaA) is a surface-exposed protein of the gram-positive bacterium Streptococcus pneumoniae. It belongs to a group of proteins designated the lipoprotein receptor I antigen family. The gene encoding PsaA from an encapsulated strain of pneumococcal serotype 6B was cloned and sequenced. The peptide sequence was compared to that of homologs found in S. pneumoniae serotype 2, viridans streptococci, and Enterococcus faecalis. Identity values among the deduced peptides ranged from 57 to 98%. The polymorphism of psaA was examined among the 23 encapsulated vaccine serotypes by using PCR-restriction fragment length polymorphism analysis. Ten different enzymes were used to analyze 80 strains representing the 23 serotypes in a 23-valent polysaccharide vaccine. This analysis showed that restriction sites within the gene were highly conserved, with only a minor variation occurring in 10% of the strains, the result of an additional Tsp509I site. The lack of variation for the other restriction sites within the gene examined here indicates that psaA is genetically conserved, an important characteristic necessary for a candidate common protein vaccine.