Purification and characterization of a bacteriocin produced by Leuconostoc mesenteroides E131

Leuconostoc mesenteroides E131, isolated from Greek traditional fermented sausage, prepared without the addition of starters, produces a bacteriocin which is active against the pathogen Listeria monocytogenes. The bacteriocin was purified by 50% ammonium sulphate precipitation, cation exchange, and reverse-phase chromatography. Bacteriocin is active at pH values between 4.0 and 9.0 and retains activity after incubation for 1 h at 100 degrees C. Proteolytic enzymes inactivated the bacteriocin after 1 h of incubation, while renin resulted in full inactivation only after 24 h. Lipase resulted in full inactivation after 4 h. Applying molecular methods, it was determined that the bacteriocin produced, named as mesenterocin E131, was identical to mesenterocin Y105 and was expressed during the exponential growth phase. (C) 2007 Elsevier Ltd. All rights reserved.