RRC ID 56368
Author Dar Y, Salomon D, Bosis E.
Title The Antibacterial and Anti-Eukaryotic Type VI Secretion System MIX-Effector Repertoire in Vibrionaceae.
Journal Mar Drugs
Abstract Vibrionaceae is a widespread family of aquatic bacteria that includes emerging pathogens and symbionts. Many Vibrionaceae harbor a type VI secretion system (T6SS), which is a secretion apparatus used to deliver toxins, termed effectors, into neighboring cells. T6SSs mediate both antibacterial and anti-eukaryotic activities. Notably, antibacterial effectors are encoded together with a gene that encodes a cognate immunity protein so as to antagonize the toxicity of the effector. The MIX (Marker for type sIX effectors) domain has been previously defined as a marker of T6SS effectors carrying polymorphic C-terminal toxins. Here, we set out to identify the Vibrionaceae MIX-effector repertoire and to analyze the various toxin domains they carry. We used a computational approach to search for the MIX-effectors in the Vibrionaceae genomes, and grouped them into clusters based on the C-terminal toxin domains. We classified MIX-effectors as either antibacterial or anti-eukaryotic, based on the presence or absence of adjacent putative immunity genes, respectively. Antibacterial MIX-effectors carrying pore-forming, phospholipase, nuclease, peptidoglycan hydrolase, and protease activities were found. Furthermore, we uncovered novel virulence MIX-effectors. These are encoded by "professional MIXologist" strains that employ a cocktail of antibacterial and anti-eukaryotic MIX-effectors. Our findings suggest that certain Vibrionaceae adapted their antibacterial T6SS to mediate interactions with eukaryotic hosts or predators.
Volume 16(11)
Published 2018-11-4
DOI 10.3390/md16110433
PII md16110433
PMID 30400344
PMC PMC6267618
MeSH Anti-Bacterial Agents / metabolism Anti-Bacterial Agents / toxicity* Aquatic Organisms / metabolism* Bacterial Proteins / genetics Bacterial Proteins / metabolism Bacterial Proteins / toxicity* Computational Biology Eukaryota / physiology* Host Microbial Interactions / physiology Protein Domains / genetics Type VI Secretion Systems / genetics Type VI Secretion Systems / metabolism Type VI Secretion Systems / toxicity* Vibrionaceae / genetics Vibrionaceae / metabolism* Virulence Factors / genetics Virulence Factors / metabolism Virulence Factors / toxicity
IF 3.772
Times Cited 4
Pathogenic bacteria