Sequence diversity within the capsular genes of Streptococcus pneumoniae serogroup 6 and 19.
Sequence diversity within the capsular genes of Streptococcus pneumoniae serogroup 6 and 19.
复制标题
DOI：
10.1371/journal.pone.0025018
复制
发表时间：
2011
期刊：
影响因子：
3.7
通讯作者：
Schouls L
中科院分区：
文献类型：
--
作者：
Elberse K;Witteveen S;van der Heide H;van de Pol I;Schot C;van der Ende A;Berbers G;Schouls L
肺炎链球菌的主要毒力因子是荚膜。构成该荚膜的多糖由大约 15 个基因编码，这些基因的差异导致不同的血清型。本研究的目的是调查荷兰 6A、6B、6C、19A 和 19F 血清型荚膜基因的序列多样性，并探讨疫苗接种对这些血清型变异和分布的可能影响。对 25 个血清组 6 和 20 个血清组 19 分离株的完整荚膜基因座进行了测序。如果一个或多个基因与参考序列有 10 个或更多碱基对的差异，则将其指定为荚膜亚型。对 184 个血清组 6 和 195 个血清组 19 分离株进行等位基因特异性 PCR 和高度可变荚膜基因的特异性基因测序，以鉴定荚膜亚型。这揭示了血清型 6A、6B 和 6C 中分别存在 6、3 和单一荚膜亚型。血清型19A和19F分离株分别包含3种和4种荚膜亚型。对于血清组 6，通过多位点序列分型 (MLST) 和多位点可变串联重复次数分析 (MLVA) 确定的遗传背景似乎与荚膜亚型密切相关，但对于血清组 19 分离株而言，这一点不太明显。数据还表明，引入 7 价肺炎球菌疫苗后，血清型 6A 和 19A 中荚膜亚型的出现发生了变化。这些非疫苗血清型内的变化可能表明这些荚膜亚型正在填补疫苗血清型的空白。总之，肺炎球菌血清群 6 和 19 内的荚膜基因存在相当大的 DNA 序列变异。这种变化可能导致多糖改变或产生更多荚膜多糖的菌株。因此，这些改变的胶囊可能对疫苗诱导的免疫不太敏感。
The main virulence factor of Streptococcus pneumoniae is the capsule. The polysaccharides comprising this capsule are encoded by approximately 15 genes and differences in these genes result in different serotypes. The aim of this study was to investigate the sequence diversity of the capsular genes of serotypes 6A, 6B, 6C, 19A and 19F and to explore a possible effect of vaccination on variation and distribution of these serotypes in the Netherlands. The complete capsular gene locus was sequenced for 25 serogroup 6 and for 20 serogroup 19 isolates. If one or more genes varied in 10 or more base pairs from the reference sequence, it was designated as a capsular subtype. Allele-specific PCRs and specific gene sequencing of highly variable capsular genes were performed on 184 serogroup 6 and 195 serogroup 19 isolates to identify capsular subtypes. This revealed the presence of 6, 3 and a single capsular subtype within serotypes 6A, 6B and 6C, respectively. The serotype 19A and 19F isolates comprised 3 and 4 capsular subtypes, respectively. For serogroup 6, the genetic background, as determined by multi locus sequence typing (MLST) and multiple- locus variable number of tandem repeat analysis (MLVA), seemed to be closely related to the capsular subtypes, but this was less pronounced for serogroup 19 isolates. The data also suggest shifts in the occurrence of capsular subtypes within serotype 6A and 19A after introduction of the 7-valent pneumococcal vaccine. The shifts within these non-vaccine serotypes might indicate that these capsular subtypes are filling the niche of the vaccine serotypes. In conclusion, there is considerable DNA sequence variation of the capsular genes within pneumococcal serogroup 6 and 19. Such changes may result in altered polysaccharides or in strains that produce more capsular polysaccharides. Consequently, these altered capsules may be less sensitive for vaccine induced immunity.
登录
查看更多内容
影响因子：
6.4
作者：
Beall, Bernard W.;Gertz, Robert E.;Brueggemann, Angela B.
通讯作者：
Brueggemann, Angela B.
影响因子：
9.4
作者：
Jefferies, JMC;Smith, A;Mitchell, TJ
通讯作者：
Mitchell, TJ
影响因子：
15.3
作者：
Llull, D;Munoz, R;Lopez, R;Garcia, E
通讯作者：
Garcia, E
影响因子：
3.2
作者：
Cartee, RT;Forsee, WT;Yother, J
通讯作者：
Yother, J
DOI：
10.1099/00221287-144-11-3049
发表时间：
1998-11-01
期刊：
MICROBIOLOGY-UK
影响因子：
--
作者：
Enright, MC;Spratt, BG
通讯作者：
Spratt, BG