Substrate-induced double sided H-bond network as a means of domain closure in 3-phosphoglycerate kinase.
Closure of the two domains of 3-phosphoglycerate kinase, upon substrate binding, is essential for the enzyme function. The available crystal structures cannot provide sufficient information about the mechanism of substrate assisted domain closure and about the requirement of only one or both substrates, since lattice forces may hinder the large scale domain movements. In this study the known X-ray data, obtained for the open and closed conformations, were probed by solution small-angle X-ray scattering experiments. The results prove that binding of both substrates is essential for domain closure. Molecular graphical analysis, indeed, reveals formation of a double-sided H-bond network, which affects substantially the shape of the main molecular hinge at beta-strand L, under the concerted action of both substrates.
Varga
Andrea
A
Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1518 Budapest, P.O. Box 7, Hungary.
Flachner
Beáta
B
Konarev
Peter
P
Gráczer
Eva
E
Szabó
Judit
J
Svergun
Dmitri
D
Závodszky
Péter
P
Vas
Mária
M
D005988:Glyceric Acids / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D006860:Hydrogen Bonding; D008958:Models, Molecular; D010735:Phosphoglycerate Kinase / Q000737:chemistry* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity
D005988:Glyceric Acids; C005156:3-phosphoglycerate; D010735:Phosphoglycerate Kinase