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Enterococcus faecalis pCF10-encoded surface proteins PrgA, PrgB (aggregation substance) and PrgC contribute to plasmid transfer, biofilm formation and virulence. | LitMetric

AI Article Synopsis

  • Enterococcus faecalis pCF10 transfers plasmids efficiently when the prgQ operon is activated by pheromones, utilizing PrgA, PrgB, PrgC, and a type IV secretion system for delivery to recipient cells.* -
  • The study shows that PrgB and extracellular DNA are essential for cell aggregation and high-frequency plasmid transfer, while PrgA is crucial for binding to surfaces and biofilm development.* -
  • Although PrgB is linked to virulence, PrgA and PrgC are needed for effective killing in a worm infection model, suggesting that the surface functions of these proteins play a vital role in bacterial attachment and gene transfer in natural environments.*

Article Abstract

Enterococcus faecalis pCF10 transfers at high frequencies upon pheromone induction of the prgQ transfer operon. This operon codes for three cell wall-anchored proteins - PrgA, PrgB (aggregation substance) and PrgC - and a type IV secretion system through which the plasmid is delivered to recipient cells. Here, we defined the contributions of the Prg surface proteins to plasmid transfer, biofilm formation and virulence using the Caenorhabditis elegans infection model. We report that a combination of PrgB and extracellular DNA (eDNA), but not PrgA or PrgC, was required for extensive cellular aggregation and pCF10 transfer at wild-type frequencies. In addition to PrgB and eDNA, production of PrgA was necessary for extensive binding of enterococci to abiotic surfaces and development of robust biofilms. However, although PrgB is a known virulence factor in mammalian infection models, we determined that PrgA and PrgC, but not PrgB, were required for efficient killing in the worm infection model. We propose that the pheromone-responsive, conjugative plasmids of E. faecalis have retained Prg-like surface functions over evolutionary time for attachment, colonization and robust biofilm development. In natural settings, these biofilms are polymicrobial in composition and constitute optimal environments for signal exchange, mating pair formation and widespread lateral gene transfer.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4329047PMC
http://dx.doi.org/10.1111/mmi.12893DOI Listing

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