1ZUN

Crystal Structure of a GTP-Regulated ATP Sulfurylase Heterodimer from Pseudomonas syringae

Summary for 1ZUN

• Entry DOI: 10.2210/pdb1zun/pdb
• Descriptor: Sulfate adenylyltransferase subunit 2, sulfate adenylate transferase, subunit 1/adenylylsulfate kinase, MAGNESIUM ION, ... (7 entities in total)
• Functional Keywords: beta barrel, switch domain, heterodimer, pyrophosphate, g protein, gtpase, transferase
• Biological source: Pseudomonas syringae; More
• Total number of polymer chains: 2
• Total formula weight: 87232.37

Authors

Mougous, J.D.,Lee, D.H.,Hubbard, S.C.,Schelle, M.W.,Vocadlo, D.J.,Berger, J.M.,Bertozzi, C.R. (deposition date: 2005-05-31, release date: 2006-01-17, Last modification date: 2024-11-13)

Primary citation

Mougous, J.D.,Lee, D.H.,Hubbard, S.C.,Schelle, M.W.,Vocadlo, D.J.,Berger, J.M.,Bertozzi, C.R.
Molecular basis for g protein control of the prokaryotic ATP sulfurylase.
Mol.Cell, 21:109-122, 2006

PubMed Abstract: 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.

PubMed: 16387658
DOI: 10.1016/j.molcel.2005.10.034

Experimental method

X-RAY DIFFRACTION (2.7 Å)