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Alkylcysteine Sulfoxide C-S Monooxygenase Uses a Flavin-Dependent Pummerer Rearrangement.

ABSTRACT: Flavoenzymes are highly versatile and participate in the catalysis of a wide range of reactions, including key reactions in the metabolism of sulfur-containing compounds. S-Alkyl cysteine is formed primarily by the degradation of S-alkyl glutathione generated during electrophile detoxification. A recently discovered S-alkyl cysteine salvage pathway uses two flavoenzymes (CmoO and CmoJ) to dealkylate this metabolite in soil bacteria. CmoO catalyzes a stereospecific sulfoxidation, and CmoJ catalyzes the cleavage of one of the sulfoxide C-S bonds in a new reaction of unknown mechanism. In this paper, we investigate the mechanism of CmoJ. We provide experimental evidence that eliminates carbanion and radical intermediates and conclude that the reaction proceeds via an unprecedented enzyme-mediated modified Pummerer rearrangement. The elucidation of the mechanism of CmoJ adds a new motif to the flavoenzymology of sulfur-containing natural products and demonstrates a new strategy for the enzyme-catalyzed cleavage of C-S bonds.

SUBMITTER: Hazra S

PROVIDER: S-EPMC10863075 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Alkylcysteine Sulfoxide C-S Monooxygenase Uses a Flavin-Dependent Pummerer Rearrangement.

Hazra Sohan S Begley Tadhg P TP

Journal of the American Chemical Society 20230525 22

Flavoenzymes are highly versatile and participate in the catalysis of a wide range of reactions, including key reactions in the metabolism of sulfur-containing compounds. S-Alkyl cysteine is formed primarily by the degradation of S-alkyl glutathione generated during electrophile detoxification. A recently discovered S-alkyl cysteine salvage pathway uses two flavoenzymes (CmoO and CmoJ) to dealkylate this metabolite in soil bacteria. CmoO catalyzes a stereospecific sulfoxidation, and CmoJ catalyz ...[more]

PMID: 37229602

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Dataset Information

Alkylcysteine Sulfoxide C-S Monooxygenase Uses a Flavin-Dependent Pummerer Rearrangement.

Publications

Alkylcysteine Sulfoxide C-S Monooxygenase Uses a Flavin-Dependent Pummerer Rearrangement.

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