School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia.
Infect Genet Evol. 2012 Mar;12(2):492-5. doi: 10.1016/j.meegid.2012.01.001. Epub 2012 Jan 24.
Evolutionary studies using single nucleotide polymorphisms (SNPs) have separated Bordetella pertussis isolates into six major clusters, with recent isolates forming cluster I. The expansion of cluster I isolates was characterised by changes in genes encoding antigenic components in acellular vaccines, including pertactin (Prn). Here, we determined the initial emergence of the pertussis toxin promoter allele, ptxP3, from an evolutionary perspective. This allele was previously shown in a study from the Netherlands to be associated with increased pertussis toxin production as a result of a single base mutation in the ptxP. The ptxP region of 313 worldwide isolates was sequenced, including 208 isolates from Australia collected over a 40 year period. Eight alleles were identified, of which only two predominated: ptxP1 and ptxP3. One novel allele was also found. ptxP3 was only found in SNP cluster I of B. pertussis and its emergence is concurrent with the change to the non-vaccine prn2 allele. Our results suggest that the globally distributed cluster I of B. pertussis has the ability to evade vaccine induced selection pressure.
使用单核苷酸多态性 (SNP) 的进化研究将百日咳博德特氏菌分离株分为六个主要簇，最近的分离株形成簇 I。簇 I 分离株的扩张特征是无细胞疫苗中编码抗原成分的基因发生变化，包括 pertactin (Prn)。在这里，我们从进化的角度确定了百日咳毒素启动子等位基因 ptxP3 的最初出现。该等位基因之前在荷兰的一项研究中显示与百日咳毒素产量增加有关，这是由于 ptxP 中的单个碱基突变。对来自全球的 313 个分离株的 ptxP 区进行了测序，其中包括澳大利亚 40 年来收集的 208 个分离株。确定了 8 个等位基因，其中只有两个占主导地位：ptxP1 和 ptxP3。还发现了一个新的等位基因。ptxP3 仅在 B. pertussis 的 SNP 簇 I 中发现，其出现与非疫苗 prn2 等位基因的变化同时发生。我们的研究结果表明，在全球范围内分布的 B. pertussis 簇 I 具有逃避疫苗诱导的选择压力的能力。
