title: Induction of bacteriocin production by coculture is widespread among plantaricin-producing Lactobacillus plantarum strains with different regulatory operons.
abstract: We describe the bacteriocin-production phenotype in a group of eight singular bacteriocinogenic Lactobacillus plantarum strains with three distinct genotypes regarding the plantaricin locus. Genotyping of these strains revealed the existence of two different plantaricin-production regulatory operons, plNC8-plNC8HK-plnD or plnABCD, involving three-component systems controlled each of them by a specific autoinducer peptide (AIP), i.e. PLNC8IF or PlnA. While all of the strains produced antimicrobial activity when growing on solid medium, most of them halted this production when cultured in broth, thus reflecting the functionality of regulatory mechanisms. Antimicrobial activity in broth cultures was re-established or enhanced when the specific AIP was added to the culture or by coculturing with specific bacterial strains. The latter trait appeared to be widespread in bacteriocinogenic L. plantarum strains independently of the regulatory system used to regulate bacteriocin production or the specific bacteriocins produced. The induction spectrum through coculture, i.e. the pattern of bacterial strains able to induce bacteriocin production, was characteristic of each individual L. plantarum strain. Also, the ability of some bacteria to induce bacteriocin production in L. plantarum by coculture appeared to be strain specific. The fact that induction of bacteriocin production by coculturing appeared to be a common feature in L. plantarum can be exploited accordingly to enhance the viability of this species in food and feed fermentations, as well as to contribute to probiotic functionality when colonising the gastrointestinal tract.
authors.affiliation: Departamento de Biotecnología de Alimentos, Instituto de la Grasa, Consejo Superior de Investigaciones Científicas, Avda. Padre García Tejero 4, Aptdo. 1078, 41012 Sevilla, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Maldonado-Barragán
authors.forename: Belén
authors.initials: B
authors.lastname: Caballero-Guerrero
authors.forename: Helena
authors.initials: H
authors.lastname: Lucena-Padrós
authors.forename: José Luis
authors.initials: JL
authors.lastname: Ruiz-Barba
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001430:Bacteriocins / Q000096:biosynthesis*; D018920:Coculture Techniques; D015964:Gene Expression Regulation, Bacterial; D048191:Lactiplantibacillus plantarum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D009876:Operon; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins