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1g8m
From Proteopedia
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CRYSTAL STRUCTURE OF AVIAN ATIC, A BIFUNCTIONAL TRANSFORMYLASE AND CYCLOHYDROLASE ENZYME IN PURINE BIOSYNTHESIS AT 1.75 ANG. RESOLUTION
Overview
ATIC, the product of the purH gene, is a 64 kDa bifunctional enzyme that, possesses the final two activities in de novo purine biosynthesis, AICAR, transformylase and IMP cyclohydrolase. The crystal structure of avian ATIC, has been determined to 1.75 A resolution by the MAD method using a, Se-methionine modified enzyme. ATIC forms an intertwined dimer with an, extensive interface of approximately 5,000 A(2) per monomer. Each monomer, is composed of two novel, separate functional domains. The N-terminal, domain (up to residue 199) is responsible for the IMPCH activity, whereas, the AICAR Tfase activity resides in the C-terminal domain (200-593). The, active sites of the IMPCH and AICAR Tfase domains are approximately 50 A, apart, with no structural evidence of a tunnel connecting the two active, sites. The crystal structure of ATIC provides a framework to probe both, catalytic mechanisms and to design specific inhibitors for use in cancer, chemotherapy and inflammation.
About this Structure
1G8M is a Single protein structure of sequence from Gallus gallus with K and G as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of a bifunctional transformylase and cyclohydrolase enzyme in purine biosynthesis., Greasley SE, Horton P, Ramcharan J, Beardsley GP, Benkovic SJ, Wilson IA, Nat Struct Biol. 2001 May;8(5):402-6. PMID:11323713
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