Appl. Environ. Microbiol. doi:10.1128/AEM.02559-07
Copyright (c) 2008, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.
Cloning and Heterologous Production of Hiracin JM79, a Sec-Dependent Bacteriocin Produced by Enterococcus hirae DCH5, in Lactic Acid Bacteria (LAB) and Pichia pastoris
Jorge Sánchez,
Juan Borrero,
Beatriz Gómez-Sala,
Antonio Basanta,
Carmen Herranz,
Luis M. Cintas,
and
Pablo E. Hernández*
Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain
* To whom correspondence should be addressed. Email:
ehernan{at}vet.ucm.es.
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Abstract |
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Hiracin JM79 (HirJM79), a Sec-dependent bacteriocin produced by Enterococcus hirae DCH5, was cloned and produced in Lactococcus lactis, Lactobacillus sakei, Enterococcus faecium, Enterococcus faecalis, and Pichia pastoris. For heterologous production of HirJM79 in lactic acid bacteria (LAB) the HirJM79 structural gene (hirJM79), with or without the HirJM79 immunity gene (hiriJM79), was cloned in plasmid pMG36c under control of the constitutive promoter P32, and in plasmid pNZ8048 under control of the inducible PNisApromoter. For production of HirJM79 in P. pastoris, the gene encoding the mature HirJM79 was cloned into the pPICZ
A expression vector. The recombinant plasmids permitted the production of biologically active HirJM79 in the supernatants of L. lactis IL1403, L. lactis NZ9000, Lb. sakei 790, E. faecalis JH2-2, and P. pastoris X-33, the coproduction of HirJM79 and nisin A (NisA) in L. lactis DPC5598, and the coproduction of HirJM79 and enterocin P (EntP) in E. faecium L50/14-2. All recombinant LAB produced larger quantities of HirJM79 than E. hirae DCH5, although the antimicrobial activity of most transformants was lower than predicted from their production of HirJM79. The synthesis, processing, and secretion of HirJM79 proceeds efficiently in the recombinant LAB strains and P. pastoris.