• Extensive bacteriocin gene shuffling in the Streptococcus bovis/Streptococcus equinus complex reveals gallocin D with activity against vancomycin resistant enterococci

      Hill, Daragh; O’Connor, Paula M.; Altermann, Eric; Day, Li; Hill, Colin; STANTON, CATHERINE; Ross, Paul; Teagasc Walsh Fellowship Programme; Science Foundation Ireland; SFI/12/RC/2273 (Springer Science and Business Media LLC, 2020-08-10)
      Streptococcus gallolyticus LL009 produces gallocin D, a narrow spectrum two component bacteriocin with potent activity against vancomycin-resistant enterococci. Gallocin D is distinct from gallocin A, a separate two component bacteriocin produced by S. gallolyticus. Although the gene clusters encoding gallocin A and gallocin D have a high degree of gene synteny, the structural genes are highly variable and appear to have undergone gene shufing with other streptococcal species. Gallocin D was analysed in laboratory-based experiments. The mature peptides are 3,343± 1 Da and 3,019 ± 1 Da and could be readily synthesized and display activity against a vancomycin resistant Enterococcus strain EC300 with a MIC value of 1.56 µM. Importantly, these bacteriocins could contribute to the ability of S. gallolyticus to colonize the colon where they have been associated with colorectal cancer.