Structure of the electron transfer complex between ferredoxin and ferredoxin-NADP(+) reductase

Citation
G. Kurisu et al., Structure of the electron transfer complex between ferredoxin and ferredoxin-NADP(+) reductase, NAT ST BIOL, 8(2), 2001, pp. 117-121
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
NATURE STRUCTURAL BIOLOGY
ISSN journal
1072-8368 → ACNP
Volume
8
Issue
2
Year of publication
2001
Pages
117 - 121
Database
ISI
SICI code
1072-8368(200102)8:2<117:SOTETC>2.0.ZU;2-O
Abstract
All oxygenic photosynthetically derived reducing equivalents are utilized b y combinations of a single multifuctional electron carrier protein, ferredo xin (Fd), and several Fd-dependent oxidoreductases, We report the first cry stal structure of the complex between maize leaf Pd and Fd-NADP(+) oxidored uctase (FNR), The redox centers in the complex - the 2Fe-2S cluster of Pd a nd flavin adenine dinucleotide (FAD) of FNR - are in close proximity; the s hortest distance is 6.0 Angstrom. The intermolecular interactions in the co mplex are mainly electrostatic, occurring through salt bridges, and the int erface near the prosthetic groups is hydrophobic. NMR experiments on the co mplex in solution confirmed the FNR recognition sites on Fd that are identi fied in the crystal structure. interestingly. the structures of Pd and FNR in the complex and in the free state differ in several ways. For example, i n the active site of FNR, Pd binding induces the formation of a new hydroge n bond between side chains of Glu 312 and Ser 96 of FNR. We propose that th is type of molecular communication not only determines the optimal orientat ion of the two proteins for electron transfer, but also contributes to the modulation of the enzymatic properties of FNR.