4BR7: Legionella Pneumophila Ntpdase1 Crystal Form I, Open, Ampnp Complex

Citation:
Abstract
In vertebrates, membrane-bound ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) on the cell surface are responsible for signal conversion and termination in purinergic signaling by extracellular nucleotides. Here we present apo and complex structures of the rat NTPDase2 extracellular domain and Legionella pneumophila NTPDase1, including a high-resolution structure with a transition-state analog. Comparison of ATP and ADP binding modes shows how NTPDases engage the same catalytic site for hydrolysis of nucleoside triphosphates and diphosphates. We find that this dual specificity is achieved at the expense of base specificity. Structural and mutational studies indicate that a conserved active-site water is replaced by the phosphate product immediately after phosphoryl transfer. Partial base specificity for purines in LpNTPDase1 is based on a different intersubunit base binding site for pyrimidine bases. A comparison of the bacterial enzyme in six independent crystal forms shows that NTPDases can undergo a domain closure motion of at least 17 degrees .
PDB ID: 4BR7Download
MMDB ID: 111774
PDB Deposition Date: 2013/6/4
Updated in MMDB: 2013/12
Experimental Method:
x-ray diffraction
Resolution: 1.8  Å
Source Organism:
Similar Structures:
Biological Unit for 4BR7: dimeric; determined by author and by software (PISA)
Molecular Components in 4BR7
Label Count Molecule
Proteins (2 molecules)
2
Ectonucleoside Triphosphate Diphosphohydrolase I
Molecule annotation
Chemicals (7 molecules)
1
1
2
2
3
4
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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