2PW3: Structure Of The Pde4d-Camp Complex

Phosphodiesterases (PDEs) are key enzymes that control the cellular concentrations of the second messengers cAMP and cGMP. The mechanism for selective recognition of substrates cAMP and cGMP by individual PDE families remains a puzzle. To understand the mechanism for substrate recognition by PDE enzymes, the crystal structure of the catalytic domain of an inactive D201N mutant of PDE4D2 in complex with substrate cAMP has been determined at 1.56 A resolution. The structure shows that Gln369 forms only one hydrogen bond with the adenine of cAMP. This finding provides experimental evidence against the hypothesis of two hydrogen bonds between the invariant glutamine and the substrate cAMP in PDE4, and thus suggests that the widely circulated "glutamine switch" model is unlikely the mechanism for substrate recognition by PDEs. A structure comparison between PDE4D2-cAMP and PDE10A2-cAMP reveals an anti configuration of cAMP in PDE4D2 but syn in PDE10A2, in addition to different contact patterns of cAMP in these two structures. These observations imply that individual PDE families have their characteristic mechanisms for substrate recognition.
PDB ID: 2PW3Download
MMDB ID: 60177
PDB Deposition Date: 2007/5/10
Updated in MMDB: 2007/11
Experimental Method:
x-ray diffraction
Resolution: 1.56  Å
Source Organism:
Similar Structures:
Biological Unit for 2PW3: dimeric; determined by author
Molecular Components in 2PW3
Label Count Molecule
Proteins (2 molecules)
Camp-specific 3',5'-cyclic Phosphodiesterase 4D(Gene symbol: PDE4D)
Molecule annotation
Chemicals (4 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB