Premium
Structure and mechanism of the iron‐sulfur flavoprotein phthalate dioxygenase reductase
Author(s) -
Gassner George T.,
Ludwig Martha L.,
Gatti Domenico L.,
Correll Carl C.,
Ballou David P.
Publication year - 1995
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.9.14.7589982
Subject(s) - ferredoxin , flavoprotein , chemistry , flavin group , reductase , nad+ kinase , electron transfer , cofactor , stereochemistry , flavin mononucleotide , flavin adenine dinucleotide , photochemistry , biochemistry , enzyme
Transfer of electrons between pyri‐dine nucleotides (obligatory two‐electron carriers) and hemes or [2Fe‐2S] centers (obligatory one‐electron carriers) is an essential step mediated by flavins in respiration, photosynthesis, and many oxygenase systems. Phthalate dioxygenase reductase (PDR), a soluble iron‐sulfur flavoprotein from Pscudomofias cepacia , is a convenient model for the study of this type of electron transfer. PDR is folded into thrjee domains; the NH2terminal FMN binding and central NAD(H) binding domains are closely related to ferredoxin‐NADP + reductase (FNR). The COOH‐términal [2Fe‐2S] domain is similar to plaUt ferredoxins, and can be removed by proteolysis without significantly altering the reactivity of the FNR‐like domains. Kinetic studies have identified sequential steps in the reaction of PDR with NADH that involve pyridine nucleotide binding, hydrijde transfer to FMN, and intramolecular electron transfer from the reduced flavin to the [2Fe‐2S] cluster. Crystal structures of reduced and liganded PDR correspond to some of the intermediates formed during reduction by NADH. Small structural changes that are observed in the vicinity of the cofactors upon reduction or NAD(H) binding may provide part of the reorganization energy or contribute to the gating mechanism that controls intramolecular electron transfer.—Gassner, G. T., Ludwig, M. L., Gatti, D. L., Correll, C. C., Ballou, D. P. Structure and mechanism of the iron‐sulfur flavoprotein phthalate dioxygenase reductase. FASEB J. 9, 1411‐1418 (1995)