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Cytochrome P450–catalyzed L-tryptophan nitration in thaxtomin phytotoxin biosynthesis.

ABSTRACT: Thaxtomin phytotoxins produced by plant-pathogenic Streptomyces species contain a nitro group that is essential for phytotoxicity. The N,N'-dimethyldiketopiperazine core of thaxtomins is assembled from L-phenylalanine and L-4-nitrotryptophan by a nonribosomal peptide synthetase, and nitric oxide synthase-generated NO is incorporated into the nitro group, but the biosynthesis of the nonproteinogenic amino acid L-4-nitrotryptophan is unclear. Here we report that TxtE, a unique cytochrome P450, catalyzes L-tryptophan nitration using NO and O(2).

SUBMITTER: Barry SM

PROVIDER: S-EPMC3522571 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Cytochrome P450–catalyzed L-tryptophan nitration in thaxtomin phytotoxin biosynthesis.

Barry Sarah M SM Kers Johan A JA Johnson Evan G EG Song Lijiang L Aston Philip R PR Patel Bhumit B Krasnoff Stuart B SB Crane Brian R BR Gibson Donna M DM Loria Rosemary R Challis Gregory L GL

Nature chemical biology 20121001 10

Thaxtomin phytotoxins produced by plant-pathogenic Streptomyces species contain a nitro group that is essential for phytotoxicity. The N,N'-dimethyldiketopiperazine core of thaxtomins is assembled from L-phenylalanine and L-4-nitrotryptophan by a nonribosomal peptide synthetase, and nitric oxide synthase-generated NO is incorporated into the nitro group, but the biosynthesis of the nonproteinogenic amino acid L-4-nitrotryptophan is unclear. Here we report that TxtE, a unique cytochrome P450, cat ...[more]

PMID: 22941045

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