Divergicin 750, a novel bacteriocin produced by Carnobacterium divergens 750

Abstract Divergicin 750, a bacteriocin produced by Carnobacterium divergens 750, preferentially inhibited the growth of strains of Carnobacterium and Enterococcus . Selected strains of Listeria monocytogenes and Clostridium perfringens were also inhibited. The bacteriocin was purified to homogeneity by ammonium sulfate precipitation and sequential S-Sepharose, hydrophobic interaction and reversed phase chromatography. The complete amino acid sequence was determined by Edman degradation. The peptide consisted of 34 amino acid residues. The calculated ifM_r from the peptide sequence, 3447.7, agreed well with that obtained by mass spectrometry. Divergicin 750 did not show any sequence similarities to other known bacteriocins. The plasmid-located structural gene encoding divergicin 750 ( dvn750 ) was cloned and sequenced. The gene encoded a primary translation product of 63 amino acids with a deduced M _rmr = 6789.4 which is cleaved between amino acid residues 29 and 30 to yield the mature bacteriocin.