Article citationsMore>>

Nayar, P., Brun, A., Harriman, A., Begley, T.P. (1992) Mechanistic studies on protochlorophyllide reductase: A model system for the enzymatic reaction. Journal of the Chemical Society, Chemical Communications, 5, 395-397. doi:10.1039/c39920000395

has been cited by the following article:

• TITLE: Advances in understanding of the primary reactions of protochlorophyll(ide) photoreduction in cells and model systems

  AUTHORS: Olga B. Belyaeva, Felix F. Litvin

  KEYWORDS: Protochlorophyllide; Chlorophyllide; Photoreduction; Fluorescence; Spectroscopy

  JOURNAL NAME: Journal of Biophysical Chemistry, Vol.2 No.1, February 22, 2011

  ABSTRACT: The key step in chlorophyll biosynthesis is photoreduction of its immediate precursor, protochlorophyllide. This reaction is catalyzed by a photoenzyme, protochlorophyllide oxidoreductase (POR) and consists in the attachment of two hydrogen atoms in positions C17 and C18 of the tetrapyrrole molecule of protochlorophyllide; the double bond is replaced with the single bond. Two hydrogen donors involved in protochloro-phyllide photoreduction are NADPH [1,2] and a conserved tyrosine residue Tyr193 of the photoenzyme POR [3]. The structure of active pigment-enzyme complex (Pchlide-POR-NADPH) ensures a favorable steric conditions for the transfer of hydride ion and proton. This review does not examine the ternary complex structure, but concentrates upon the mechanisms of primary photophysical and photochemical reactions during formation of chlorophyllide from protochlorophyllide in living objects (etiolated leaves and leaf homogenates) and model systems.