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Chlorophyll a oxygenase (CAO) is involved in chlorophyll b formation from chlorophyll a.

ABSTRACT: Chlorophyll b is an ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. Its biosynthesis plays a key role in the adaptation to various light environments. We isolated six chlorophyll b-less mutants by insertional mutagenesis by using the nitrate reductase or argininosuccinate lyase genes as tags and examined the rearrangement of mutant genomes. We found that an overlapping region of a nuclear genome was deleted in all mutants and that this encodes a protein whose sequence is similar to those of methyl monooxygenases. This coding sequence also contains putative binding domains for a [2Fe-2S] Rieske center and for a mononuclear iron. The results demonstrate that a chlorophyll a oxygenase is involved in chlorophyll b formation. The reaction mechanism of chlorophyll b formation is discussed.

SUBMITTER: Tanaka A

PROVIDER: S-EPMC22897 | biostudies-literature | 1998 Oct

REPOSITORIES: biostudies-literature

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Chlorophyll a oxygenase (CAO) is involved in chlorophyll b formation from chlorophyll a.

Tanaka A A Ito H H Tanaka R R Tanaka N K NK Yoshida K K Okada K K

Proceedings of the National Academy of Sciences of the United States of America 19981001 21

Chlorophyll b is an ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. Its biosynthesis plays a key role in the adaptation to various light environments. We isolated six chlorophyll b-less mutants by insertional mutagenesis by using the nitrate reductase or argininosuccinate lyase genes as tags and examined the rearrangement of mutant genomes. We found that an overlapping region of a nuclear genome was deleted in all mutants and that this encodes a protein whose seque ...[more]

PMID: 9770552

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