Reconstitution of a sequential reaction of two nitrogenase-like enzymes in the bacteriochlorophyll biosynthetic pathway of Rhodobacter capsulatus.
The parental structure of bacteriochlorophyll a, bacteriochlorin, is formed by a sequential operation of two nitrogenase-like enzymes, dark-operative protochlorophyllide oxidoreductase (DPOR) and chlorophyllide a oxidoreductase (COR). Both DPOR and COR consist of two components, Fe protein and MoFe protein cognates. Here we determined kinetic parameters of COR and established the reconstitution system for the formation of bacteriochlorin (3-vinyl bacteriochlorophyllide a) from porphyrin (protochlorophyllide) with purified components of DPOR and COR from Rhodobacter capsulatus. This reconstitution system confirmed the recent finding that COR catalyzes 8-vinyl reduction of 8-vinyl chlorophyllide a in addition to the known activity of C7C8 double bond reduction, and provides a promising model to investigate how two nitrogenase-like enzymes are coordinated in bacteriochlorophyll biosynthesis.
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
Haruki
H
Yamamoto
School of Agricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
Mina
M
Kato
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
Kaori
K
Yamanashi
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan. Electronic address: fujita@agr.nagoya-u.ac.jp.
Yuichi
Y
Fujita
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D001429:Bacteriochlorophylls / Q000096:biosynthesis* / Q000378:metabolism; D053898:Biosynthetic Pathways; D007700:Kinetics; D009591:Nitrogenase / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000737:chemistry / Q000378:metabolism*; D011166:Porphyrins / Q000737:chemistry / Q000378:metabolism; D011521:Protochlorophyllide / Q000737:chemistry / Q000378:metabolism; D016354:Rhodobacter capsulatus / Q000201:enzymology / Q000378:metabolism*
D001426:Bacterial Proteins; D001429:Bacteriochlorophylls; D011166:Porphyrins; C452433:bacteriochlorin; D011521:Protochlorophyllide; D009591:Nitrogenase; D044925:Oxidoreductases Acting on CH-CH Group Donors; C023886:protochlorophyllide reductase
8-Vinyl reductase; Bacteriochlorophyll; Chlorophyllide; Nitrogenase; Protochlorophyllide