Stress-related genes promote Edwardsiella ictaluri pathogenesis

PLoS One. 2018 Mar 19;13(3):e0194669. doi: 10.1371/journal.pone.0194669. eCollection 2018.

Abstract

Edwardsiella ictaluri is a Gram-negative facultative anaerobic rod and the causative agent of enteric septicemia of channel catfish (ESC), which is one of the most prevalent diseases of catfish, causing significant economic losses in the catfish industry. E. ictaluri is resistant to complement system and macrophage killing, which results in rapid systemic septicemia. However, mechanisms of E. ictaluri stress responses under conditions of host environment are not studied well. Therefore, in this work, we report E. ictaluri stress responses during hydrogen peroxide, low pH, and catfish serum stresses as well as during catfish invasion. E. ictaluri stress responses were characterized by identifying expression of 13 universal stress protein (USP) genes (usp01-usp13) and seven USP-interacting protein genes (groEL, groES, dnaK, grpE, and clpB, grpE, relA). Data indicated that three usp genes (usp05, usp07, and usp13) were highly expressed in all stress conditions. Similarly, E. ictaluri heat shock proteins groEL, groES, dnaK, grpE, and clpB were highly expressed in oxidative stress. Also, E. ictaluri grpE and relA were highly expressed in catfish spleen and head kidney. These findings contribute to our understanding of stress response mechanisms in E. ictaluri stress response, and stress-related proteins that are essential for E. ictaluri could be potential targets for live attenuated vaccine development against ESC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Progression
  • Edwardsiella ictaluri*
  • Enterobacteriaceae Infections / genetics*
  • Enterobacteriaceae Infections / pathology
  • Enterobacteriaceae Infections / veterinary
  • Fish Diseases / genetics*
  • Fish Diseases / pathology
  • Fish Proteins / genetics
  • Heat-Shock Proteins / genetics
  • Ictaluridae / microbiology*
  • Stress, Physiological / genetics*
  • Virulence / genetics

Substances

  • Fish Proteins
  • Heat-Shock Proteins

Grants and funding

This project was supported by Agriculture and Food Research Initiative competitive grant no. 2016-67015-24909 from the USDA National Institute of Food and Agriculture (AK). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.