Biological Characterization and Evolution of Bacteriophage T7-Delta holin During the Serial Passage Process

文献类型： 外文期刊

第一作者： Xu, Hai

作者： Xu, Hai;Hong, Weiming;Wang, Anping;Dong, Hongyan;Xu, Hai;Bao, Xi;Hou, Jibo;Deng, Bihua;Xu, Hai;Govinden, Roshini;Chenia, Hafizah Y. Y.;Wang, Kaimin;Deng, Bihua

作者机构：

关键词： T7 phage; holin; lysis; compensatory host; evolution

期刊名称：FRONTIERS IN MICROBIOLOGY （ 影响因子：5.64； 五年影响因子：6.32 ）

ISSN：

年卷期： 2021 年 12 卷

页码：

收录情况： SCI

摘要： Bacteriophage T7 gene 17.5 coding for the only known holin is one of the components of its lysis system, but the holin activity in T7 is more complex than a single gene, and evidence points to the existence of additional T7 genes with holin activity. In this study, a T7 phage with a gene 17.5 deletion (T7-Delta holin) was rescued and its biological characteristics and effect on cell lysis were determined. Furthermore, the genomic evolution of mutant phage T7-Delta holin during serial passage was assessed by whole-genome sequencing analysis. It was observed that deletion of gene 17.5 from phage T7 delays lysis time and enlarges the phage burst size; however, this biological characteristic recovered to normal lysis levels during serial passage. Scanning electron microscopy showed that the two opposite ends of E. coli BL21 cells swell post-T7-Delta holin infection rather than drilling holes on cell membrane when compared with T7 wild-type infection. No visible progeny phage particle accumulation was observed inside the E. coli BL21 cells by transmission electron microscopy. Following serial passage of T7- Delta holin from the 1st to 20th generations, the mRNA levels of gene 3.5 and gene 19.5 were upregulated and several mutation sites were discovered, especially two missense mutations in gene 19.5, which indicate a potential contribution to the evolution of the T7-Delta holin. Although the burst size of T7-Delta holin increased, high titer cultivation of T7-Delta holin was not achieved by optimizing the culture process. Accordingly, these results suggest that gene 19.5 is a potential lysis-related component that needs to be studied further and that the T7-Delta holin strain with its gene 17.5 deletion is not adequate to establish the high-titer phage cultivation process.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序