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Arabidopsis CHL27, located in both envelope and thylakoid membranes, is required for the synthesis of protochlorophyllide.

ABSTRACT: CHL27, the Arabidopsis homologue to Chlamydomonas Crd1, a plastid-localized putative diiron protein, is required for the synthesis of protochlorophyllide and therefore is a candidate subunit of the aerobic cyclase in chlorophyll biosynthesis. delta-Aminolevulinic acid-fed antisense Arabidopsis plants with reduced amounts of Crd1/CHL27 accumulate Mg-protoporphyrin IX monomethyl ester, the substrate of the cyclase reaction. Mutant plants have chlorotic leaves with reduced abundance of all chlorophyll proteins. Fractionation of Arabidopsis chloroplast membranes shows that Crd1/CHL27 is equally distributed on a membrane-weight basis in the thylakoid and inner-envelope membranes.

SUBMITTER: Tottey S

PROVIDER: S-EPMC307702 | biostudies-literature | 2003 Dec

REPOSITORIES: biostudies-literature

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Arabidopsis CHL27, located in both envelope and thylakoid membranes, is required for the synthesis of protochlorophyllide.

Tottey Stephen S Block Maryse A MA Allen Michael M Westergren Tomas T Albrieux Catherine C Scheller Henrik V HV Merchant Sabeeha S Jensen Poul Erik PE

Proceedings of the National Academy of Sciences of the United States of America 20031212 26

CHL27, the Arabidopsis homologue to Chlamydomonas Crd1, a plastid-localized putative diiron protein, is required for the synthesis of protochlorophyllide and therefore is a candidate subunit of the aerobic cyclase in chlorophyll biosynthesis. delta-Aminolevulinic acid-fed antisense Arabidopsis plants with reduced amounts of Crd1/CHL27 accumulate Mg-protoporphyrin IX monomethyl ester, the substrate of the cyclase reaction. Mutant plants have chlorotic leaves with reduced abundance of all chloroph ...[more]

PMID: 14673103

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