Cloning, nucleotide sequence, and expression of the gene encoding the bacteriocin boticin B from Clostridium botulinum strain 213B

Boticin B is a heat-stable bacteriocin produced by Clostridium botulinum st rain 213B that has inhibitory activity against various strains of C, botuli num and related clostridia, The gene encoding the bacteriocin was localized to a 3.0-kb HindIII fragment of an 18.8-kb plasmid, cloned, and sequenced. DNA sequencing revealed the boticin B structural gene, btcB, to be an open reading frame encoding 50 amino acids. A C, botulinum strain 62A transconj ugant containing the HindIII fragment inserted into a clostridial shuttle v ector expressed boticin B, although at much lower levels than those observe d in C, botulinum 213B, To our knowledge, this is the first demonstration a nd characterization of a bacteriocin from toxigenic group I C. botulinum.