Abstract

Bacteria in nature are widely exposed to differential fluid shears which are often a trigger for phenotypic switches. The latter mediates transcriptional and translation remodelling of cellular metabolism impacting among others virulence, antimicrobial resistance and stress resistance. In this study, we evaluated the role of fluid shear on phenotypic switch in an acute hepatopancreatic necrosis disease (AHPND)-causing Vibrio parahaemolyticus M0904 strain under both in vitro and in vivo conditions. The results showed that V. parahaemolyticus M0904 grown at lower shaking speed (110 rpm constant agitation, M0904/110), causing low fluid shear, develop cellular aggregates or floccules. These cells increased levan production (as verified by concanavalin binding) and developed differentially stained colonies on Congo red agar plates and resistance to antibiotics. In addition, the phenotypic switch causes a major shift in the protein secretome. At 120 rpm (M0904/120), PirA(VP)/PirB(VP) toxins are mainly produced, while at 110 rpm PirA(VP)/PirB(VP) toxins production is stopped and an alkaline phosphatase (ALP) PhoX becomes the dominant protein in the protein secretome. These observations are matched with a very strong reduction in virulence of M0904/110 towards two crustacean larvae, namely, Artemia and Macrobrachium. Taken together, our study provides substantial evidence for the existence of two phenotypic forms in AHPND V. parahaemolyticus strain displaying differential phenotypes. Moreover, as aerators and pumping devices are frequently used in shrimp aquaculture facilities, they can inflict fluid shear to the standing microbial agents. Hence, our study could provide a basis to understand the behaviour of AHPND-causing V. parahaemolyticus in aquaculture settings and open the possibility to monitor and control AHPND by steering phenotypes.

Published in

Environmental Microbiology
2020, Volume: 22, number: 10, pages: 4212-4230
Publisher: WILEY

SLU Authors

• Baruah, Kartik

  • Department of Applied Animal Science and Welfare, Swedish University of Agricultural Sciences
    
  • Ghent University

Associated SLU-program

AMR: Bacteria


Sustainable Development Goals

SDG14 Conserve and sustainably use the oceans, seas and marine resources for sustainable development
SDG3 Ensure healthy lives and promote well-being for all at all ages


UKÄ Subject classification

Microbiology


Publication identifier

DOI: https://doi.org/10.1111/1462-2920.14903

Permanent link to this page (URI)

https://res.slu.se/id/publ/103841