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Characterization of benzoyl coenzyme A biosynthesis genes in the enterocin-producing bacterium "Streptomyces maritimus".

ABSTRACT: The novel benzoyl coenzyme A (benzoyl-CoA) biosynthesis pathway in "Streptomyces maritimus" was investigated through a series of target-directed mutations. Genes involved in benzoyl-CoA formation were disrupted through single-crossover homologous recombination, and the resulting mutants were analyzed for their ability to biosynthesize the benzoyl-CoA-primed polyketide antibiotic enterocin. Inactivation of the unique phenylalanine ammonia-lyase-encoding gene encP was previously shown to be absolutely required for benzoyl-CoA formation in "S. maritimus". The fatty acid beta-oxidation-related genes encH, -I, and -J, on the other hand, are necessary but not required. In each case, the yield of benzoyl-CoA-primed enterocin dropped below wild-type levels. We attribute the reduced benzoyl-CoA formation in these specific mutants to functional substitution and cross-talk between the products of genes encH, -I, and -J and the enzyme homologues of primary metabolism. Disruption of the benzoate-CoA ligase encN gene did not perturb enterocin production, however, demonstrating that encN is extraneous and that benzoic acid is not a pathway intermediate. EncN rather serves as a substitute pathway for utilizing exogenous benzoic acid. These experiments provide further support that benzoyl-CoA is formed in a novel bacterial pathway that resembles the eukaryotic assembly of benzoyl-CoA from phenylalanine via a beta-oxidative path.

SUBMITTER: Xiang L

PROVIDER: S-EPMC145315 | biostudies-literature | 2003 Jan

REPOSITORIES: biostudies-literature

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Characterization of benzoyl coenzyme A biosynthesis genes in the enterocin-producing bacterium "Streptomyces maritimus".

Xiang Longkuan L Moore Bradley S BS

Journal of bacteriology 20030101 2

The novel benzoyl coenzyme A (benzoyl-CoA) biosynthesis pathway in "Streptomyces maritimus" was investigated through a series of target-directed mutations. Genes involved in benzoyl-CoA formation were disrupted through single-crossover homologous recombination, and the resulting mutants were analyzed for their ability to biosynthesize the benzoyl-CoA-primed polyketide antibiotic enterocin. Inactivation of the unique phenylalanine ammonia-lyase-encoding gene encP was previously shown to be absolu ...[more]

PMID: 12511484

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Dataset Information

Characterization of benzoyl coenzyme A biosynthesis genes in the enterocin-producing bacterium "Streptomyces maritimus".

Publications

Characterization of benzoyl coenzyme A biosynthesis genes in the enterocin-producing bacterium "Streptomyces maritimus".

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