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Enzymological and structural characterization of Arabidopsis thaliana heme oxygenase-1.

ABSTRACT: Arabidopsis thaliana heme oxygenase-1 (AtHO-1), a metabolic enzyme in the heme degradation pathway, serves as a prototype for study of the bilin-related functions in plants. Past biological analyses revealed that AtHO-1 requires ferredoxin-NADP⁺ reductase (FNR) and ferredoxin for its enzymatic activity. Here, we characterized the binding and degradation of heme by AtHO-1, and found that ferredoxin is a dispensable component of the reducing system that provides electrons for heme oxidation. Furthermore, we reported the crystal structure of heme-bound AtHO-1, which demonstrates both conserved and previously undescribed features of plant heme oxygenases. Finally, the electron transfer pathway from FNR to AtHO-1 is suggested based on the known structural information.

SUBMITTER: Wang J

PROVIDER: S-EPMC9433822 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Enzymological and structural characterization of Arabidopsis thaliana heme oxygenase-1.

Wang Jia J Li Xiaoyi X Chang Jing-Wen JW Ye Tong T Mao Ying Y Wang Xiao X Liu Lin L

FEBS open bio 20220620 9

Arabidopsis thaliana heme oxygenase-1 (AtHO-1), a metabolic enzyme in the heme degradation pathway, serves as a prototype for study of the bilin-related functions in plants. Past biological analyses revealed that AtHO-1 requires ferredoxin-NADP<sup>+</sup> reductase (FNR) and ferredoxin for its enzymatic activity. Here, we characterized the binding and degradation of heme by AtHO-1, and found that ferredoxin is a dispensable component of the reducing system that provides electrons for heme oxida ...[more]

PMID: 35689519

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