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Crystal structure of the dimethylsulfide monooxygenase DmoA from Hyphomicrobium sulfonivorans.

ABSTRACT: DmoA is a monooxygenase which uses dioxygen (O₂) and reduced flavin mononucleotide (FMNH₂) to catalyze the oxidation of dimethylsulfide (DMS). Although it has been characterized, the structure of DmoA remains unknown. Here, the crystal structure of DmoA was determined to a resolution of 2.28?Å and was compared with those of its homologues LadA and BdsA. The results showed that their overall structures are similar: they all share a conserved TIM-barrel fold which is composed of eight ?-helices and eight ?-strands. In addition, they all have five additional insertions. Detailed comparison showed that the structures have notable differences despite their high sequence similarity. The substrate-binding pocket of DmoA is smaller compared with those of LadA and BdsA.

SUBMITTER: Cao HY

PROVIDER: S-EPMC6277965 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Crystal structure of the dimethylsulfide monooxygenase DmoA from Hyphomicrobium sulfonivorans.

Cao Hai Yan HY Wang Peng P Peng Ming M Shao Xuan X Chen Xiu Lan XL Li Chun Yang CY

Acta crystallographica. Section F, Structural biology communications 20181126 Pt 12

DmoA is a monooxygenase which uses dioxygen (O<sub>2</sub>) and reduced flavin mononucleotide (FMNH<sub>2</sub>) to catalyze the oxidation of dimethylsulfide (DMS). Although it has been characterized, the structure of DmoA remains unknown. Here, the crystal structure of DmoA was determined to a resolution of 2.28 Å and was compared with those of its homologues LadA and BdsA. The results showed that their overall structures are similar: they all share a conserved TIM-barrel fold which is composed ...[more]

PMID: 30511672

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