1psd is a 2 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The crystal structure of the phosphoglycerate dehydrogenase from Escherichia coli is unique among dehydrogenases. It consists of three clearly separate domains connected by flexible hinges. The tetramer has approximate 222 symmetry with the principal contacts between the subunits forming between either the nucleotide binding domains or the regulatory domains. Two slightly different subunit conformations are present which vary only in the orientations of the domains. There is a hinge-like arrangement near the active site cleft and the serine effector site is provided by the regulatory domain of each of two subunits. Interdomain flexibility may play a key role in both catalysis and allosteric inhibition.
The allosteric ligand site in the Vmax-type cooperative enzyme phosphoglycerate dehydrogenase.,Schuller DJ, Grant GA, Banaszak LJ Nat Struct Biol. 1995 Jan;2(1):69-76. PMID:7719856[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Schuller DJ, Grant GA, Banaszak LJ. The allosteric ligand site in the Vmax-type cooperative enzyme phosphoglycerate dehydrogenase. Nat Struct Biol. 1995 Jan;2(1):69-76. PMID:7719856