Genetic boundaries delineate the potential human pathogen Salmonella bongori into discrete lineages: divergence and speciation
Genetic boundaries delineate the potential human pathogen Salmonella bongori into discrete lineages: divergence and speciation
复制标题
遗传边界将潜在的人类病原体邦戈里沙门氏菌划分为离散的谱系：分歧和物种形成
DOI：
10.1186/s12864-019-6259-z
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发表时间：
2019-12-04
期刊：
影响因子：
4.4
通讯作者：
Liu，Shu-Lin
中科院分区：
文献类型：
--
作者：
Wang，Xiaoyu;Zhu，Songling;Liu，Shu-Lin
背景邦戈里沙门氏菌主要感染冷血宿主，但也有沙门氏菌感染。已有报道 bongoriin 温血宿主。我们假设 S. bongori可能已经分化成不同的系统发育谱系，其中一些能够感染温血宿主。 bongori，我们首先对长尾小鹦鹉分离株RKS3044进行了完整测序，并将其与其他已测序的S进行了比较。邦戈里斯列车。我们发现RKS3044除了包含所有S共有的SPI-22编码的T6SS之外，还包含一个以致病性岛状结构编码的新型T6SS。迄今为止报道的邦戈里斯菌株。这种新颖的 T6SS 类似于感染沙门氏菌 I 亚组谱系的温血宿主的 SPI-19 T6SS。基因组序列比较揭示了 S 之间不同的基因组序列改善事件。 bongoristrains，包括 RKS3044 中独特的 CTAG 四核苷酸变性模式，表明 RKS3044 和 otherS 之间的基因库不重叠。 bongorilineages/菌株导致其基因组变异的独立积累。我们进一步证明了RKS3044与其他S之间存在明确的遗传界限。本研究中分析了 bongorilineages/菌株。 结论bongoristrain RKS3044 与其他菌株具有不同的基因组特征。 bongoristrains，包括一种新的 T6SS，编码为以前未报道的致病性岛状结构和独特的基因组序列退化模式。这些发现提醒人们注意，通过获得特定的致病性状，源自非致病祖先的新病原体的出现。
BackgroundSalmonella bongoriinfect mainly cold-blooded hosts, but infections byS. bongoriin warm-blooded hosts have been reported. We hypothesized thatS. bongorimight have diverged into distinct phylogenetic lineages, with some being able to infect warm-blooded hosts.ResultsTo inspect the divergence status ofS. bongori, we first completely sequenced the parakeet isolate RKS3044 and compared it with other sequencedS. bongoristrains. We found that RKS3044 contained a novel T6SS encoded in a pathogenicity island-like structure, in addition to a T6SS encoded in SPI-22, which is common to allS. bongoristrains so far reported. This novel T6SS resembled the SPI-19 T6SS of the warm-blooded host infectingSalmonellaSubgroup I lineages. Genomic sequence comparisons revealed different genomic sequence amelioration events among theS. bongoristrains, including a unique CTAG tetranucleotide degeneration pattern in RKS3044, suggesting non-overlapping gene pools between RKS3044 and otherS. bongorilineages/strains leading to their independent accumulation of genomic variations. We further proved the existence of a clear-cut genetic boundary between RKS3044 and the otherS. bongorilineages/strains analyzed in this study.ConclusionsThe warm-blooded host-infectingS. bongoristrain RKS3044 has diverged with distinct genomic features from otherS. bongoristrains, including a novel T6SS encoded in a previously not reported pathogenicity island-like structure and a unique genomic sequence degeneration pattern. These findings alert cautions about the emergence of new pathogens originating from non-pathogenic ancestors by acquiring specific pathogenic traits.