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Dibenzothiophene Catabolism Proceeds via a Flavin-N5-oxide Intermediate.

ABSTRACT: The dibenzothiophene catabolic pathway converts dibenzothiophene to 2-hydroxybiphenyl and sulfite. The third step of the pathway, involving the conversion of dibenzothiophene sulfone to 2-(2-hydroxyphenyl)-benzenesulfinic acid, is catalyzed by a unique flavoenzyme DszA. Mechanistic studies on this reaction suggest that the C2 hydroperoxide of dibenzothiophene sulfone reacts with flavin to form a flavin-N5-oxide. The intermediacy of the flavin-N5-oxide was confirmed by LC-MS analysis, a co-elution experiment with chemically synthesized FMN-N5-oxide and (18)O2 labeling studies.

SUBMITTER: Adak S

PROVIDER: S-EPMC6078383 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Dibenzothiophene Catabolism Proceeds via a Flavin-N5-oxide Intermediate.

Adak Sanjoy S Begley Tadhg P TP

Journal of the American Chemical Society 20160510 20

The dibenzothiophene catabolic pathway converts dibenzothiophene to 2-hydroxybiphenyl and sulfite. The third step of the pathway, involving the conversion of dibenzothiophene sulfone to 2-(2-hydroxyphenyl)-benzenesulfinic acid, is catalyzed by a unique flavoenzyme DszA. Mechanistic studies on this reaction suggest that the C2 hydroperoxide of dibenzothiophene sulfone reacts with flavin to form a flavin-N5-oxide. The intermediacy of the flavin-N5-oxide was confirmed by LC-MS analysis, a co-elutio ...[more]

PMID: 27120486

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