1XNJ

APS complex of human PAPS synthetase 1

Summary for 1XNJ

• Entry DOI: 10.2210/pdb1xnj/pdb
• Related: 1X6V 1XJQ
• Descriptor: Bifunctional 3'-phosphoadenosine 5'-phosphosulfate synthetase 1, ADENOSINE-5'-DIPHOSPHATE, ADENOSINE-5'-PHOSPHOSULFATE, ... (4 entities in total)
• Functional Keywords: transferase, atp sulfurylase, aps kinase, paps, phosphoadenosine phosphosulfate
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 2
• Total formula weight: 145106.94

Authors

Harjes, S.,Bayer, P.,Scheidig, A.J. (deposition date: 2004-10-05, release date: 2005-08-30, Last modification date: 2023-08-23)

Primary citation

Harjes, S.,Bayer, P.,Scheidig, A.J.
The crystal structure of human PAPS synthetase 1 reveals asymmetry in substrate binding
J.Mol.Biol., 347:623-635, 2005

PubMed Abstract: The high energy sulfate donor 3'-phosphoadenosine-5-phosphosulfate (PAPS) is used for sulfate conjugation of extracellular matrix, hormones and drugs. Human PAPS synthetase 1 catalyzes two subsequent reactions starting from ATP and sulfate. First the ATP sulfurylase domain forms APS, then the APS kinase domain phosphorylates the APS intermediate to PAPS. Up to now the interaction between the two enzymatic activities remained elusive, mainly because of missing structural information. Here we present the crystal structure of human PAPSS1 at 1.8 angstroms resolution. The structure reveals a homodimeric, asymmetric complex with the shape of a chair. The two kinase domains adopt different conformational states, with only one being able to bind its two substrates. The asymmetric binding of ADP to the APS kinase is not only observed in the crystal structure, but can also be detected in solution, using an enzymatic assay. These observations strongly indicate structural changes during the reaction cycle. Furthermore crystals soaked with ADP and APS could be prepared and the corresponding structures could be solved.

PubMed: 15755455
DOI: 10.1016/j.jmb.2005.01.005

Experimental method

X-RAY DIFFRACTION (1.98 Å)