Genetic characterisation and heterologous expression of leucocin C, a class IIa bacteriocin from Leuconostoc carnosum 4010

Genetic characterization and expression of leucocin B, a class IId bacteriocin from Leuconostoc carnosum 4010

“…In our previous study, we localized the leucocin C operon by partial sequencing of an 8-kb AclI restriction fragment from a large plasmid, pLC4010-1 [18]. Here, further sequencing of the AclI fragment revealed a single gene and a two-gene operon downstream of lecS, the leucocin C secretion gene (Fig.…”

“…As strain 4010 is generally regarded as safe for food, understanding its antimicrobial properties is important. The strain has been shown to produce antilisterial leucocins A and C. In our previous study, we characterized the gene clusters required for production of leucocins A and C in L. carnosum 4010 [18]. In this study, we identified a novel bacteriocin operon for leucocin B expression in L. carnosum 4010 and further studied bacteriocin production in native and heterologous hosts.…”

“…L. lactis strains used were lcnA and lebB expression strains LAC428 and LAC410 constructed in this study, and lecC expression strain LAC409 made previously [18]. L. lactis strain LAC360 carrying the vector pLEB690 [21] was used as a negative control.…”

“…The bacteriocins were concentrated from culture supernatants and the activities were analyzed on an L. pseudomesenteroides CIP103316 indicator plate. The leucocins A and B were compared with leucocin C previously cloned in L. lactis [18] and with the wild-type leucocins from L. carnosum 4010. All three heterologous leucocins and L. carnosum 4010 produced inhibition zones on the CIP103316 plate (Fig.…”

“…carnosum 4010 plasmids were isolated according to Anderson and McKay [19] with modifications described in our previous study [18]. Vectors and constructed plasmids from L. lactis were isolated with GeneJET Plasmid Miniprep Kit (Thermo Scientific, Waltham, MA, USA).…”