1m8p
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Crystal Structure of P. chrysogenum ATP Sulfurylase in the T-state
OverviewOverview
The structure of the cooperative hexameric enzyme ATP sulfurylase from, Penicillium chrysogenum bound to its allosteric inhibitor, 3'-phosphoadenosine-5'-phosphosulfate (PAPS), was determined to 2.6 A, resolution. This structure represents the low substrate-affinity T-state, conformation of the enzyme. Comparison with the high substrate-affinity, R-state structure reveals that a large rotational rearrangement of domains, occurs as a result of the R-to-T transition. The rearrangement is, accompanied by the 17 A movement of a 10-residue loop out of the active, site region, resulting in an open, product release-like structure of the, catalytic domain. Binding of PAPS is proposed to induce the allosteric, transition by destabilizing an R-state-specific salt linkage between Asp, 111 in an N-terminal domain of one subunit and Arg 515 in the allosteric, domain of a trans-triad subunit. Disrupting this salt linkage by, site-directed mutagenesis induces cooperative inhibition behavior in the, absence of an allosteric effector, confirming the role of these two, residues.
About this StructureAbout this Structure
1M8P is a Single protein structure of sequence from Penicillium chrysogenum with PPS as ligand. Active as Sulfate adenylyltransferase, with EC number 2.7.7.4 Full crystallographic information is available from OCA.
ReferenceReference
Allosteric inhibition via R-state destabilization in ATP sulfurylase from Penicillium chrysogenum., MacRae IJ, Segel IH, Fisher AJ, Nat Struct Biol. 2002 Dec;9(12):945-9. PMID:12426581
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