1zun
From Proteopedia
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Crystal Structure of a GTP-Regulated ATP Sulfurylase Heterodimer from Pseudomonas syringae
Overview
Sulfate assimilation is a critical component of both primary and secondary, metabolism. An essential step in this pathway is the activation of sulfate, through adenylation by the enzyme ATP sulfurylase (ATPS), forming, adenosine 5'-phosphosulfate (APS). Proteobacterial ATPS overcomes this, energetically unfavorable reaction by associating with a regulatory G, protein, coupling the energy of GTP hydrolysis to APS formation. To, discover the molecular basis of this unusual role for a G protein, we, biochemically characterized and solved the X-ray crystal structure of a, complex between Pseudomonas syringae ATPS (CysD) and its associated, regulatory G protein (CysN). The structure of CysN*D shows the two, proteins in tight association; however, the nucleotides bound to each, subunit are spatially segregated. We provide evidence that conserved, switch motifs in the G domain of CysN allosterically mediate interactions, between the nucleotide binding sites. This structure suggests a molecular, mechanism by which conserved G domain architecture is used to, energetically link GTP turnover to the production of an essential, metabolite.
About this Structure
1ZUN is a Protein complex structure of sequences from Pseudomonas syringae and Pseudomonas syringae pv. tomato str. dc3000 with MG, NA, GDP and AGS as ligands. Active as Sulfate adenylyltransferase, with EC number 2.7.7.4 Full crystallographic information is available from OCA.
Reference
Molecular basis for G protein control of the prokaryotic ATP sulfurylase., Mougous JD, Lee DH, Hubbard SC, Schelle MW, Vocadlo DJ, Berger JM, Bertozzi CR, Mol Cell. 2006 Jan 6;21(1):109-22. PMID:16387658
Page seeded by OCA on Wed Nov 21 07:40:21 2007
Categories: Protein complex | Pseudomonas syringae | Pseudomonas syringae pv. tomato str. dc3000 | Sulfate adenylyltransferase | Berger, J.M. | Bertozzi, C.R. | Hubbard, S.C. | Lee, D.H. | Mougous, J.D. | Schelle, M.W. | Vocadlo, D.J. | AGS | GDP | MG | NA | Beta barrel | G protein | Gtpase | Heterodimer | Pyrophosphate | Switch domain