1nh7
ATP PHOSPHORIBOSYLTRANSFERASE (ATP-PRTASE) FROM MYCOBACTERIUM TUBERCULOSIS
OverviewOverview
The N-1-(5'-phosphoribosyl)-ATP transferase catalyzes the first step of the histidine biosynthetic pathway and is regulated by a feedback mechanism by the product histidine. The crystal structures of the N-1-(5'-phosphoribosyl)-ATP transferase from Mycobacterium tuberculosis in complex with inhibitor histidine and AMP has been determined to 1.8 A resolution and without ligands to 2.7 A resolution. The active enzyme exists primarily as a dimer, and the histidine-inhibited form is a hexamer. The structure represents a new fold for a phosphoribosyltransferase, consisting of three continuous domains. The inhibitor AMP binds in the active site cavity formed between the two catalytic domains. A model for the mechanism of allosteric inhibition has been derived from conformational differences between the AMP:His-bound and apo structures.
About this StructureAbout this Structure
1NH7 is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of ATP phosphoribosyltransferase from Mycobacterium tuberculosis., Cho Y, Sharma V, Sacchettini JC, J Biol Chem. 2003 Mar 7;278(10):8333-9. Epub 2003 Jan 2. PMID:12511575 Page seeded by OCA on Sat May 3 02:31:37 2008