Background Helicobacter pylori is a pathogenic bacterium that causes various gastrointestinal diseases in the human stomach. H. pylori is well adapted to the human stomach but does not easily infect other animals. As a model animal, Mongolian gerbils are often used, however, the genome of the inoculated H. pylori may accumulate mutations to adapt to the new host. To investigate mutations occurring in H. pylori after infection in Mongolian gerbils, we compared the whole genome sequence of TN2 wild type strain (TN2wt) and next generation sequencing data of retrieved strains from the animals after different lengths of infection. Results We identified mutations in 21 loci of 17 genes of the post-inoculation strains. Of the 17 genes, five were outer membrane proteins that potentially influence on the colonization and inflammation. Missense and nonsense mutations were observed in 15 and 6 loci, respectively. Multiple mutations were observed in three genes. Mutated genes included babA, tlpB, and gltS, which are known to be associated with adaptation to murine. Other mutations were involved with chemoreceptor, pH regulator, and outer membrane proteins, which also have potential to influence on the adaptation to the new host. Conclusions We confirmed mutations in genes previously reported to be associated with adaptation to Mongolian gerbils. We also listed up genes that mutated during the infection to the gerbils, though it needs experiments to prove the influence on adaptation.

中文翻译：

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幽门螺杆菌接种蒙古沙鼠后的全基因组突变分析。

背景幽门螺杆菌是一种致病菌，可在人体胃部引起各种胃肠道疾病。H. pylori 很好地适应了人类的胃，但不容易感染其他动物。作为模型动物，蒙古沙鼠经常被使用，然而，接种H. pylori的基因组可能会积累突变以适应新的宿主。为了研究蒙古沙鼠感染后幽门螺杆菌中发生的突变，我们比较了 TN2 野生型菌株 (TN2wt) 的全基因组序列和在不同感染长度后从动物中检索到的菌株的下一代测序数据。结果 我们在接种后菌株的 17 个基因的 21 个位点中鉴定出突变。在 17 个基因中，有 5 个是可能影响定植和炎症的外膜蛋白。分别在 15 个和 6 个位点观察到错义和无义突变。在三个基因中观察到多个突变。突变基因包括 babA、tlpB 和 gltS，已知它们与对鼠的适应有关。其他突变与化学感受器、pH 调节剂和外膜蛋白有关，它们也有可能影响对新宿主的适应。结论 我们证实了先前报道的与蒙古沙鼠适应有关的基因突变。我们还列出了在沙鼠感染期间发生突变的基因，尽管它需要实验来证明对适应的影响。已知与对鼠的适应有关。其他突变与化学感受器、pH 调节剂和外膜蛋白有关，它们也有可能影响对新宿主的适应。结论 我们证实了先前报道的与蒙古沙鼠适应有关的基因突变。我们还列出了在沙鼠感染期间发生突变的基因，尽管它需要实验来证明对适应的影响。已知与对鼠的适应有关。其他突变与化学感受器、pH 调节剂和外膜蛋白有关，它们也有可能影响对新宿主的适应。结论 我们证实了先前报道的与蒙古沙鼠适应有关的基因突变。我们还列出了在沙鼠感染期间发生突变的基因，尽管它需要实验来证明对适应的影响。