The RNA Chaperone Hfq Is Involved in Colony Morphology, Nutrient Utilization and Oxidative and Envelope Stress Response in Vibrio alginolyticus.

Yiqin Deng,Xiaochun Huang,Yiying Yang,Jingjing Zhao,Annick Jacq,Chang Chen,Zhe Zhao,Mikael Skurnik

doi:10.1371/journal.pone.0163689

Abstract

Hfq is a global regulator that is involved in environmental adaptation of bacteria and in pathogenicity. To gain insight into the role of Hfq in Vibrio alginolyticus, an hfq deletion mutant was constructed in V. alginolyticus ZJ-T strain and phenotypically characterized. Deletion of hfq led to an alteration of colony morphology and reduced extracellular polysaccharide production, a general impairment of growth in both rich medium and minimal media with different carbon sources or amino acids, enhanced sensitivity to oxidative stress and to several antibiotics. Furthermore, a differential transcriptomic analysis showed significant changes of transcript abundance for 306 protein coding genes, with 179 genes being up regulated and 127 down-regulated. Several of these changes could be related to the observed phenotypes of the mutant. Transcriptomic data also provided evidence for the induction of the extracytoplasmic stress response in absence of Hfq. Altogether, these findings point to broad regulatory functions for Hfq in V. alginolyticus cells, likely to underlie an important role in pathogenicity.

Highlights

Vibrio alginolyticus is a common gram-negative halophilic bacterium that is part of the normal microflora in marine environment worldwide
Escherichia coli strains were cultured in Luria–Bertani (LB) (Invitrogen, USA) medium supplemented with appropriate antibiotics at 37°C
We checked by Quantitative RT-PCR (qPCR) expression of all three genes in the three strains: WT, Δhfq and the complementation strain

Summary

Introduction

Vibrio alginolyticus is a common gram-negative halophilic bacterium that is part of the normal microflora in marine environment worldwide. More and more studies suggest that it is a potential threat to marine animals and humans by causing serious infections [1,2,3]. A recent report showed that the incidence of diseases caused by vibrios in USA has dramatically increased in the last decade and V. alginolyticus has been listed as one of the most. The Role of RNA Chaperone Hfq in Vibrio alginolyticus (2014B030301064), http://www.gdstc.gov.cn/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

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