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Structural and Functional Analysis of Nonheme Iron Enzymes BCMO-1 and BCMO-2 from Caenorhabditis elegans.

ABSTRACT: Carotenoid metabolism is critical for diverse physiological processes. The nematode Caenorhabditis elegans has two genes that are annotated as β-carotene 15,15'-monooxygenase (BCMO) and are 17 centimorgan apart on chromosome II, but the function of BCMO-1 and BCMO-2 remains uncharacterized. Sequence homology indicates that the two enzymes belong to the carotenoid cleavage dioxygenase family that share a seven-bladed β-propeller fold with a nonheme iron center. Here we determined crystal structures of BCMO-1 and BCMO-2 at resolutions of 1.8 and 1.9 Å, respectively. Structural analysis reveals that BCMO-1 and BCMO-2 are strikingly similar to each other. We also characterized their β-carotene cleavage activity, but the results suggest that they may not act as β-carotene 15,15'-oxygenases.

SUBMITTER: Pan W

PROVIDER: S-EPMC8866865 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Structural and Functional Analysis of Nonheme Iron Enzymes BCMO-1 and BCMO-2 from <i>Caenorhabditis elegans</i>.

Pan Weimin W Zhou Yong-Ling YL Wang Jian J Dai Huai-En HE Wang Xiao X Liu Lin L

Frontiers in molecular biosciences 20220210

Carotenoid metabolism is critical for diverse physiological processes. The nematode <i>Caenorhabditis elegans</i> has two genes that are annotated as β-carotene 15,15'-monooxygenase (BCMO) and are 17 centimorgan apart on chromosome II, but the function of BCMO-1 and BCMO-2 remains uncharacterized. Sequence homology indicates that the two enzymes belong to the carotenoid cleavage dioxygenase family that share a seven-bladed β-propeller fold with a nonheme iron center. Here we determined crystal s ...[more]

PMID: 35223999

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