AUTHOR=Yang Lianzhi , Wang Yaping , Yu Pan , Ren Shunlin , Zhu Zhuoying , Jin Yinzhe , Yan Jizhou , Peng Xu , Chen Lanming 

TITLE=Prophage-Related Gene VpaChn25_0724 Contributes to Cell Membrane Integrity and Growth of Vibrio parahaemolyticus CHN25

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=10

YEAR=2020

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2020.595709

DOI=10.3389/fcimb.2020.595709

ISSN=2235-2988

ABSTRACT=<p><italic>Vibrio parahaemolyticus</italic> is a leading seafood-borne pathogen that can cause acute gastroenteritis and even death in humans. In aquatic ecosystems, phages constantly transform bacterial communities by horizontal gene transfer. Nevertheless, biological functions of prophage-related genes in <italic>V. parahaemolyticus</italic> remain to be fully unveiled. Herein, for the first time, we studied one such gene <italic>VpaChn25_0724</italic> encoding an unknown hypothetical protein in <italic>V. parahaemolyticus</italic> CHN25. This gene deletion mutant Δ<italic>VpaChn25_0724</italic> was constructed by homologous recombination, and its complementary mutant Δ<italic>VpaChn25_0724</italic>-com was also obtained. The Δ<italic>VpaChn25_0724</italic> mutant exhibited a sever defect in growth and swimming motility particularly at lower temperatures. Biofilm formation and cytotoxicity capacity of <italic>V. parahaemolyticus</italic> CHN25 was significantly lowered in the absence of <italic>VpaChn25_0724</italic>. Comparative secretomic analysis revealed an increase in extracellular proteins of Δ<italic>VpaChn25_0724</italic>, which likely resulted from its damaged cell membrane. Comparison of transcriptome data showed twelve significantly altered metabolic pathways in Δ<italic>VpaChn25_0724</italic>, suggesting inactive transport and utilization of carbon sources, repressed energy production and membrane biogenesis in <italic>ΔVpaChn25_0724</italic>. Comparative transcriptomic analysis also revealed several remarkably down-regulated key regulators in bacterial gene regulatory networks linked to the observed phenotypic variations. Overall, the results here facilitate better understanding of biological significance of prophage-related genes remaining in <italic>V. parahaemolyticus</italic>.</p>