1J70: Crystal Structure Of Yeast Atp Sulfurylase

Citation:
Abstract
ATP sulfurylase catalyzes the first step in the activation of sulfate by transferring the adenylyl-moiety (AMP approximately ) of ATP to sulfate to form adenosine 5'-phosphosulfate (APS) and pyrophosphate (PP(i)). Subsequently, APS kinase mediates transfer of the gamma-phosphoryl group of ATP to APS to form 3'-phosphoadenosine 5'-phosphosulfate (PAPS) and ADP. The recently determined crystal structure of yeast ATP sulfurylase suggests that its C-terminal domain is structurally quite independent from the other domains, and not essential for catalytic activity. It seems, however, to dictate the oligomerization state of the protein. Here we show that truncation of this domain results in a monomeric enzyme with slightly enhanced catalytic efficiency. Structural alignment of the C-terminal domain indicated that it is extremely similar in its fold to APS kinase although not catalytically competent. While carrying out these structural and functional studies a surface groove was noted. Careful inspection and modeling revealed that the groove is sufficiently deep and wide, as well as properly positioned, to act as a substrate channel between the ATP sulfurylase and APS kinase-like domains of the enzyme.
PDB ID: 1J70Download
MMDB ID: 23299
PDB Deposition Date: 2001/5/15
Updated in MMDB: 2012/11
Experimental Method:
x-ray diffraction
Resolution: 2.3  Å
Source Organism:
Similar Structures:
Biological Unit for 1J70: hexameric; determined by author
Molecular Components in 1J70
Label Count Molecule
Proteins (6 molecules)
6
ATP Sulphurylase(Gene symbol: MET3)
Molecule annotation
Chemicals (9 molecules)
1
6
2
3
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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