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Photoactivation studies of zinc porphyrin-myoglobin system and its application for light-chemical energy conversion.

ABSTRACT: An artificial zinc porphyrin-myoglobin-based photo-chemical energy conversion system, consisting of ZnPP-Mb or ZnPE(1)-Mb as a photosensitizer, NADP(+) as an electron acceptor, and triethanolamine as an electron donor, has been constructed to mimic photosystem I. The photoirradiated product is able to reduce a single-electron acceptor protein cytochrome c, but cannot catalyze the two-electron reduction of acetaldehyde by alcohol dehydrogenase, thus demonstrating a single electron transfer mechanism. Furthermore, the artificial system can bifunctionally promote oxidoredox reactions, depending on the presence or absence of a sacrificial electron donor, thus suggesting its potential application in electrochemical regeneration steps involved in chemical transformation and/or energy conversion.

SUBMITTER: Chang CH

PROVIDER: S-EPMC3204410 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Photoactivation studies of zinc porphyrin-myoglobin system and its application for light-chemical energy conversion.

Chang Chin-Hao CH Hu Yi-Ting YT Lo Chen-Fu CF Luo Liyang L Lin Hung-Ming HM Chang Cheng-Hsiang CH Lin Ching-Yao CY Diau Eric Wei-Guang EW Wu Tung-Kung TK

International journal of biological sciences 20111027 8

An artificial zinc porphyrin-myoglobin-based photo-chemical energy conversion system, consisting of ZnPP-Mb or ZnPE(1)-Mb as a photosensitizer, NADP(+) as an electron acceptor, and triethanolamine as an electron donor, has been constructed to mimic photosystem I. The photoirradiated product is able to reduce a single-electron acceptor protein cytochrome c, but cannot catalyze the two-electron reduction of acetaldehyde by alcohol dehydrogenase, thus demonstrating a single electron transfer mechan ...[more]

PMID: 22043177

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