PDF(Pubmed)
Abstract：
Vibrio parahaemolyticus is a food-borne pathogen, which is often isolated from various seafood products. In this study, two kinds of bacteriophages was isolated from the offshore sediments samples. The anti-phage mutant strain were obtained after seventeen rounds of co-culture of Vibrio parahaemolyticus and mixed bacteriophage, multigroup sequencing was carried out on spontaneous the anti-phage mutant strain and the wild-type strain. We used the Sanger sequencing to verify the accuracy of the mutation sites. Biolog GEN III MicroPlates were used to evaluate the metabolic capacity of wild-type strains and the anti-phage mutant strain. In this study, we found that with flaG gene (slight homology to N terminus of multiple flagellins) mutated, making the bacteriophage unable to absorb to the cell surface of the host. And, the growth competitiveness of the anti-phage mutant strain is lower than the wild-type strain. These results indicated that the fitness cost, including loss of the growth competitiveness, constitutes a barrier to the prevalence of these defense mechanisms. And the selection pressure on different anti-phage strategies depends on the trade-off between mortality imposed by bacteriophages and fitness cost of the defense strategy under the given environmental conditions. In conclusion, this study provides valuable insights into the phage-host interaction and phage resistance in Vibrio parahaemolyticus. Our study provided knowledge for the evolutionary adaption of bacteria against the bacteriophage, which could add more information to understand the phage resistance mechanism before applying in the industry.
摘要：
副溶血性弧菌是一种食源性病原体，通常从各种海鲜产品中分离出来。在这项研究中,从近海沉积物样品中分离出两种噬菌体。副溶血性弧菌与混合噬菌体共培养17轮后获得抗噬菌体突变株,对自发的抗噬菌体突变株和野生型株进行了多组测序。我们使用Sanger测序来验证突变位点的准确性。BiologGENIII微板用于评估野生型菌株和抗噬菌体突变菌株的代谢能力。在这项研究中,我们发现flaG基因（与多个鞭毛蛋白的N末端略有同源性）突变，使噬菌体不能吸收到宿主的细胞表面。And,抗噬菌体突变株的生长竞争力低于野生型株。这些结果表明，健身成本，包括增长竞争力的丧失，构成了这些防御机制盛行的障碍。在给定的环境条件下，不同抗噬菌体策略的选择压力取决于噬菌体施加的死亡率与防御策略的适应性成本之间的权衡。总之,这项研究为副溶血性弧菌的噬菌体-宿主相互作用和噬菌体抗性提供了有价值的见解。我们的研究为细菌对噬菌体的进化适应提供了知识，这可以在行业应用之前为了解噬菌体抗性机制增加更多信息。
