1gpd
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| , resolution 2.9Å | |||||||
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| Ligands: | , and | ||||||
| Activity: | Glyceraldehyde-3-phosphate dehydrogenase (phosphorylating), with EC number 1.2.1.12 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STUDIES OF ASYMMETRY IN THE THREE-DIMENSIONAL STRUCTURE OF LOBSTER D-GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE
OverviewOverview
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 StructureAbout this Structure
1GPD is a Single protein structure of sequence from Homarus americanus. Full crystallographic information is available from OCA.
ReferenceReference
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
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