Intestinal host analysis of F-specific RNA bacteriophage YM1

Abstract:

[Background] In recent years, F-specific RNA bacteriophages have been recognized as indicators of human norovirus contamination in aquatic environments. Recently, using Escherichia coli ATCC700891^T as host, our group isolated an F-specific RNA bacteriophage YM1 from human stool sample. This bacteriophage has the closest relationship to E. coli bacteriophage MS2. The hosts of MS2 are usually the male E. coli containing pili. [Objective] To explore the interaction of F-specific RNA bacteriophage with its host and norovirus living in the intestine, this study aimed to screen out the intestinal hosts of YM1. [Methods] Selective medium was used to screen out the E. coli strains in YM1-positive stool sample, and YM1 infection was verified. In addition, the 16S rRNA gene amplicon sequencing was employed to analyze the differences of bacterial community in stool samples before and after YM1 inoculation, and the potential intestinal hosts of YM1 in the YM1-postive stool sample were analyzed. [Results] A total of 351 E. coli strains were isolated from YM1-positive stool sample. However, YM1 infection results showed that none of them were the hosts of YM1 bacteriophage. The 16S rRNA gene amplicon sequencing showed that the relative abundance of Enterobacter sp. (OTU144) and Enterobacter sp. (OTU11) in stool samples were significantly decreased after being infected with YM1, which indicated that these two kinds of bacteria might be the potential hosts of YM1. [Conclusion] YM1 targets to certain host in an extremely specific manner. E. coli is not the intestinal host of YM1 in stool sample. At the same time, two potential hosts of YM1 have been identified, which provided directions and references for the isolation and screening of the intestinal hosts of YM1.

Key words:F-specific RNA bacteriophage;intestinal host;stool;Escherichia coli