The coral pathogen Vibrio coralliilyticus uses a T6SS to secrete a group of novel antieukaryotic effectors that contribute to virulence

Shir Mass, Hadar Cohen, Ram Podicheti, Douglas B. Rusch, Motti Gerlic, Blake Ushijima, Julia C. van Kessel, Eran Bosis, Dor Salomon

Research output: Contribution to journalArticlepeer-review

Abstract

Vibrio coralliilyticus is a pathogen of coral and shellfish, leading to devastating economic and ecological consequences worldwide. Although rising ocean temperatures correlate with increased V. coralliilyticus pathogenicity, the specific molecular mechanisms and determinants contributing to virulence remain poorly understood. Here, we systematically analyzed the type VI secretion system (T6SS), a contact-dependent toxin delivery apparatus, in V. coralliilyticus. We identified 2 omnipresent T6SSs that are activated at temperatures in which V. coralliilyticus becomes virulent; T6SS1 is an antibacterial system mediating interbacterial competition, whereas T6SS2 mediates anti-eukaryotic toxicity and contributes to mortality during infection of an aquatic model organism, Artemia salina. Using comparative proteomics, we identified the T6SS1 and T6SS2 toxin arsenals of 3 V. coralliilyticus strains with distinct disease etiologies. Remarkably, T6SS2 secretes at least 9 novel anti-eukaryotic toxins comprising core and accessory repertoires. We propose that T6SSs differently contribute to V. coralliilyticus's virulence: T6SS2 plays a direct role by targeting the host, while T6SS1 plays an indirect role by eliminating competitors.

Original languageEnglish
Article numbere3002734
JournalPLoS Biology
Volume22
Issue number9 September
DOIs
StatePublished - Sep 2024

All Science Journal Classification (ASJC) codes

  • General Neuroscience
  • General Biochemistry,Genetics and Molecular Biology
  • General Immunology and Microbiology
  • General Agricultural and Biological Sciences

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