BACTERIOCIN PRODUCTION BY CARNOBACTERIUM-PISCICOLA LV-61

Carnobacterium piscicola LV 61 produces a bacteriocin designated pisci colin 61, that is heat resistant, active over a wide pH range and inac tivated by alpha-chymotrypsin, pepsin, trypsin and papain. It is effec tive against strains of the genera Carnobacterium, Enterococcus and Li steria. Other lactic acid bacteria tested were less sensitive or resis tant to piscicolin. It is produced at temperatures from 1 to 30-degree s-C. Maximum bacteriocin activity was detected after the culture had e ntered the stationary phase of growth and when the culture was grown i n a medium with an initial pH between 8.0 and 9.0. The same high amoun ts of bacteriocin could be obtained in a culture at a constant pH of 6 .5. No bacteriocin was produced at pH 5.0. Peptone in the growth mediu m promotes bacteriocin production, whereas meat and yeast extract did not influence the amounts of bacteriocin produced. Bacteriocin product ion and immunity are probably encoded by a 22 kb plasmid.