Separation of Mg-Protoporphyrin IX and Mg-Protoporphyrin IX Monomethyl Ester Synthesized de novo by Developing Cucumber Etioplasts

T P Fuesler; C M Hanamoto; P A Castelfranco

doi:10.1104/pp.69.2.421

Separation of Mg-Protoporphyrin IX and Mg-Protoporphyrin IX Monomethyl Ester Synthesized de novo by Developing Cucumber Etioplasts

Plant Physiol. 1982 Feb;69(2):421-3. doi: 10.1104/pp.69.2.421.

Authors

T P Fuesler¹, C M Hanamoto, P A Castelfranco

Affiliation

¹ Department of Botany, University of California, Davis, California 95616.

Abstract

High pressure liquid chromatography was used to demonstrate that chelation of Mg(2+) into protoporphyrin IX precedes methylation in isolated greening etioplasts from cucumber (Cucumis sativus L. var. Beit Alpha) cotyledons. Mg-protoporphyrin IX synthesized in vitro from protoporphyrin IX, Mg(2+), and ATP or exogenous Mg-protoporphyrin IX could serve as substrates for the methylation step. In either case, S-adenosylmethionine was the methyl donor and could not be replaced by ATP plus methionine.