Isolation of a sakacin G producing lactic acid bacteria and food application

The objective of this work was to characterize and study the factors affecting the production and the application of sakacin G produced by Lactobacillus sakei CWBI-B1365. After a first screening, four bacteriocin producing lactic acid bacteria were selected. The structural genes for some of the bacteriocins were identified in the genome of these strains by amplification using specific PCR primers. Lb. sakei CWBI-B1365 has then been specifically studied. Sakacin G was identified as the only bacteriocin produced. Sequencing of a part of the sakacin G gene clusters involved in the bacteriocin production allowed to identify an original genetic organization. The pH, the temperature, the carbon source used and its concentration, as well as the meat extract quantity, strongly influence sakacin G production. Sakacin G was produced and showed antilisterial activity in beef. To obtain antilisterial activity in poultry meat, it was necessary to combine Lb. sakei CWBI-B1365 and Lb. curvatus CWBI-B28, a sakacin P producer.