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Saturation mutagenesis of selected residues of the ?-peptide of the lantibiotic lacticin 3147 yields a derivative with enhanced antimicrobial activity.

ABSTRACT: The lantibiotic lacticin 3147 consists of two ribosomally synthesized and post-translationally modified antimicrobial peptides, Ltn? and Ltn?, which act synergistically against a wide range of Gram-positive microorganisms. We performed saturation mutagenesis of specific residues of Ltn? to determine their functional importance. The results establish that Ltn? is more tolerant to change than previously suggested by alanine scanning mutagenesis. One substitution, Ltn?H23S, was identified which improved the specific activity of lacticin 3147 against one pathogenic strain, Staphylococcus aureus?NCDO1499. This represents the first occasion upon which the activity of a two peptide lantibiotic has been enhanced through bioengineering.

SUBMITTER: Field D

PROVIDER: S-EPMC3918158 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Saturation mutagenesis of selected residues of the α-peptide of the lantibiotic lacticin 3147 yields a derivative with enhanced antimicrobial activity.

Field Des D Molloy Evelyn M EM Iancu Catalin C Draper Lorraine A LA O' Connor Paula M PM Cotter Paul D PD Hill Colin C Ross R Paul RP

Microbial biotechnology 20130225 5

The lantibiotic lacticin 3147 consists of two ribosomally synthesized and post-translationally modified antimicrobial peptides, Ltnα and Ltnβ, which act synergistically against a wide range of Gram-positive microorganisms. We performed saturation mutagenesis of specific residues of Ltnα to determine their functional importance. The results establish that Ltnα is more tolerant to change than previously suggested by alanine scanning mutagenesis. One substitution, LtnαH23S, was identified which imp ...[more]

PMID: 23433070

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