Publications by authors named "Loreto Gutiez"

In this work, synthetic genes designed from (a), the native amino acid sequence of the class IIa bacteriocins enterocin HF (EntHF) and enterocin CRL35 (EntCRL35), (b) from hybrid bacteriocins derived from fusion of enterocin A (EntA) to itself and to EntHF and EntCRL35 through a tri-glycine peptide linker, and (c) from bacteriocin-derived chimeras devised from fusion of the N-terminal region of EntA and enterocin P (EntP) to the C-terminal end of EntHF and EntCRL35, were cloned in plasmid pPICZαA for expression by P. pastoris X-33. Synthetic genes encoding EntHF and EntCRL35 were also cloned in plasmid pP-αhSUMO3 for expression of the hSUMO3-fused bacteriocins by P.

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Background: Lactic acid bacteria (LAB) are part of the gut microbiota and produce ribosomally synthesized antimicrobial peptides or bacteriocins with interest as natural food preservatives and therapeutic agents. Bacteriocin-producing LAB are also attractive as probiotics. Griffon vultures (Gyps fulvus subspecies fulvus) are scavenger birds that feed almost exclusively on carrion without suffering apparent ill effects.

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Background: Bacteriocins produced by lactic acid bacteria (LAB) attract considerable interest as natural and nontoxic food preservatives and as therapeutics whereas the bacteriocin-producing LAB are considered potential probiotics for food, human and veterinary applications, and in the animal production field. Within LAB the lactobacilli are increasingly used as starter cultures for food preservation and as probiotics. The lactobacilli are also natural inhabitants of the gastrointestinal (GI) tract and attractive vectors for delivery of therapeutic peptides and proteins, and for production of bioactive peptides.

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We have evaluated the cloning and functional expression of previously described broad antimicrobial spectrum bacteriocins SRCAM 602, OR-7, E-760, and L-1077, by recombinant Pichia pastoris. Synthetic genes, matching the codon usage of P. pastoris, were designed from the known mature amino acid sequence of these bacteriocins and cloned into the protein expression vector pPICZαA.

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In this work, genes encoding gelatinase (gelE) and serine proteinase (sprE), two extracellular proteases produced by Enterococcus faecalis DBH18, were cloned in the protein expression vector pMG36c, containing the constitutive P32 promoter, generating the recombinant plasmids pCG, pCSP, and pCGSP encoding gelE, sprE, and gelE-sprE, respectively. Transformation of noncaseinolytic E. faecalis P36, E.

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The use of synthetic genes may constitute a successful approach for the heterologous production and functional expression of bacterial antimicrobial peptides (bacteriocins) by recombinant yeasts. In this work, synthetic genes with adapted codon usage designed from the mature amino acid sequence of the bacteriocin enterocin A (EntA), produced by Enterococcus faecium T136, and the mature bacteriocin E 50-52 (BacE50-52), produced by E. faecium NRRL B-32746, were synthesized.

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Enterococcus faecalis isolates from food and environmental origin were evaluated for their angiotensin-converting enzyme (ACE)-inhibitory activity (ACE-IA) after growth in bovine skim milk (BSM). Most (90% active) but not all (10% inactive) E. faecalis strains produced BSM-derived hydrolysates with high ACE-IA.

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Mature sakacin A (SakA, encoded by sapA) and its cognate immunity protein (SakI, encoded by sapiA), and two SakA-derived chimeras mimicking the N-terminal end of mature enterocin P (EntP/SakA) and mature enterocin A (EntA/SakA) together with SakI, were fused to different signal peptides (SP) and cloned into the protein expression vectors pNZ8048 and pMG36c for evaluation of their production and functional expression by different lactic acid bacteria. The amount, antimicrobial activity, and specific antimicrobial activity of SakA and its chimeras produced by Lactococcus lactis subsp. cremoris NZ9000 depended on the SP and the expression vector.

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The bacteriocin enterocin A (EntA) produced by Enterococcus faecium T136 has been successfully cloned and produced by the yeasts Pichia pastoris X-33EA, Kluyveromyces lactis GG799EA, Hansenula polymorpha KL8-1EA, and Arxula adeninivorans G1212EA. Moreover, P. pastoris X-33EA and K.

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Replacement of the leader sequence (LS) of the bacteriocin enterocin A (LS(entA)) by the signal peptides (SP) of the protein Usp45 (SP(usp45)), and the bacteriocins enterocin P (SP(entP)), and hiracin JM79 (SP(hirJM79)) permits the production, secretion, and functional expression of EntA by different lactic acid bacteria (LAB). Chimeric genes encoding the SP(usp45), the SP(entP), and the SP(hirJM79) fused to mature EntA plus the EntA immunity genes (entA+entiA) were cloned into the expression vectors pNZ8048 and pMSP3545, under control of the inducible P(nisA) promoter, and in pMG36c, under control of the constitutive P(32) promoter. The amount, antimicrobial activity, and specific antimicrobial activity of the EntA produced by the recombinant Lactococcus lactis, Enterococcus faecium, E.

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Replacement of the signal peptide (SP) of the bacteriocins enterocin P (EntP) and hiracin JM79 (HirJM79), produced by Enterococcus faecium P13 and Enterococcus hirae DCH5, respectively, by the signal peptide of Usp45 (SP(usp45)), the major Sec-dependent protein secreted by Lactococcus lactis, permits the production, secretion, and functional expression of EntP and HirJM79 by L. lactis. Chimeric genes encoding the SP(usp45) fused to either mature EntP (entP), with or without the immunity gene (entiP) or to mature HirJM79 (hirJM79), with or without the immunity gene (hiriJM79), were cloned into the expression vector pMG36c, carrying the P(32) constitutive promoter, and into pNZ8048 under control of the inducible PnisA promoter.

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