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1gpd
From Proteopedia
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STUDIES OF ASYMMETRY IN THE THREE-DIMENSIONAL STRUCTURE OF LOBSTER D-GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE
Overview
An improved electron density map of lobster, holo-D-glyceraldehyde-3-phosphate dehydrogenase has been computed to 2.9 A, resolution based on two heavy atom isomorphous derivatives. This has been, averaged only over the Q molecular 2-fold axis, which is known to be exact, in the human holoenzyme. The map showed possible asymmetry between the, subunits in which the active centers are closely related across the R axis, (that is, between the red and green or between the yellow and blue, subunits). A difference map between the electron density of citrate and, sulfate-soaked crystals gave further evidence for possible asymmetry. The, major differences of electron density between R axis-related subunits, appear around the active center and suggest the following interpretations., 1. The conformation of the adenine about the glycosidic bond is the more, frequently observed anti with a C-2' endo conformation for the ribose ring, in the red and yellow subunits, but is probably syn with a C-3' endo, conformation in the green and blue subunits.2. The adenine ribose has its, 3'-hydroxyl group hydrogen-bonded to a main chain carbonyl group in the, red and yellow subunits but not in the green and blue subunits, as a, consequence of the differing ribose conformations. 3. Cysteine-149 is more, closely associated with histidine-176 in the green and blue subunits, and, appears nearer the nicotinamide in the red and yellow subunits.
About this Structure
1GPD is a Single protein structure of sequence from Homarus americanus with PO4, ACE and NAD as ligands. Active as Glyceraldehyde-3-phosphate dehydrogenase (phosphorylating), with EC number 1.2.1.12 Full crystallographic information is available from OCA.
Reference
Studies of asymmetry in the three-dimensional structure of lobster D-glyceraldehyde-3-phosphate dehydrogenase., Moras D, Olsen KW, Sabesan MN, Buehner M, Ford GC, Rossmann MG, J Biol Chem. 1975 Dec 10;250(23):9137-62. PMID:127793
Page seeded by OCA on Tue Nov 20 16:13:14 2007
