Genetic import and phenotype specific alleles associated with hyper-invasion in Campylobacter jejuni.
Genetic import and phenotype specific alleles associated with hyper-invasion in Campylobacter jejuni.
复制标题
DOI：
10.1186/s12864-015-2087-y
复制
发表时间：
2015-10-24
期刊：
影响因子：
4.4
通讯作者：
Manning G
中科院分区：
文献类型：
--
作者：
Baig A;McNally A;Dunn S;Paszkiewicz KH;Corander J;Manning G
空肠弯曲菌是一种主要的人畜共患病原体，可引起人类胃肠炎。侵袭是空肠弯曲菌引起疾病的重要发病机制特征。在这里，我们报告了 134 个菌株的基因组分析，以确定高侵袭性菌株的独特性状。总共 134 个空肠弯曲菌基因组被用来创建系统发育树来定位高度侵入性菌株。比较基因组学导致了嵌合胶囊区域的鉴定。泛基因组方法发现了高侵袭性菌株的独特基因座或具有独特等位基因的基因座。系统发育分析表明，高侵袭性表型是一种通才性状。尽管基于全基因组系统发育，高侵入性菌株只是远缘相关，但它们都在荚膜区域内拥有与来自空肠弯曲菌亚种的荚膜基因具有高度同一性的基因。 doylei 和 C. lari。此外，还有一些高侵入性菌株特有的基因，与非 C.空肠弯曲菌基因，以及其他空肠弯曲菌中已知的主要发病机制相关基因的等位基因变体。特别是，鞭毛基因 flgD-E 和 flgL 的序列在高侵入性菌株中高度保守，与其他空肠弯曲菌中的序列不同。除了其他空肠弯曲菌中存在的经典 cdt 操纵子之外，还鉴定出一种新型细胞致死膨胀毒素 (cdt) 操纵子存在于所有高侵袭性菌株中。总体而言，除了观察到的与鞭毛基因和次级 cdt 操纵子中独特的等位基因变异的关联之外，超侵袭性表型与其他弯曲杆菌属物种在其基因组中的直系同源基因的存在密切相关，特别是在荚膜区域内，这在不同谱系中随机共享辅助等位基因的情况下不太可能。本文的在线版本 (doi:10.1186/s12864-015-2087-y) 包含补充材料，可供授权用户使用。
Campylobacter jejuni is a major zoonotic pathogen, causing gastroenteritis in humans. Invasion is an important pathogenesis trait by which C. jejuni causes disease. Here we report the genomic analysis of 134 strains to identify traits unique to hyperinvasive isolates. A total of 134 C. jejuni genomes were used to create a phylogenetic tree to position the hyperinvasive strains. Comparative genomics lead to the identification of mosaic capsule regions. A pan genome approach led to the discovery of unique loci, or loci with unique alleles, to the hyperinvasive strains. Phylogenetic analysis showed that the hyper-invasive phenotype is a generalist trait. Despite the fact that hyperinvasive strains are only distantly related based on the whole genome phylogeny, they all possess genes within the capsule region with high identity to capsule genes from C. jejuni subsp. doylei and C. lari. In addition there were genes unique to the hyper-invasive strains with identity to non-C. jejuni genes, as well as allelic variants of mainly pathogenesis related genes already known in the other C. jejuni. In particular, the sequence of flagella genes, flgD-E and flgL were highly conserved amongst the hyper-invasive strains and divergent from sequences in other C. jejuni. A novel cytolethal distending toxin (cdt) operon was also identified as present in all hyper-invasive strains in addition to the classic cdt operon present in other C. jejuni. Overall, the hyper-invasive phenotype is strongly linked to the presence of orthologous genes from other Campylobacter species in their genomes, notably within the capsule region, in addition to the observed association with unique allelic variants in flagellar genes and the secondary cdt operon which is unlikely under random sharing of accessory alleles in separate lineages. The online version of this article (doi:10.1186/s12864-015-2087-y) contains supplementary material, which is available to authorized users.