1poa
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1poa.gif|left|200px]] | [[Image:1poa.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1poa", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | | | + | --> |
| - | | | + | {{STRUCTURE_1poa| PDB=1poa | SCENE= }} |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''INTERFACIAL CATALYSIS: THE MECHANISM OF PHOSPHOLIPASE A2''' | '''INTERFACIAL CATALYSIS: THE MECHANISM OF PHOSPHOLIPASE A2''' | ||
| Line 24: | Line 21: | ||
Interfacial catalysis: the mechanism of phospholipase A2., Scott DL, White SP, Otwinowski Z, Yuan W, Gelb MH, Sigler PB, Science. 1990 Dec 14;250(4987):1541-6. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2274785 2274785] | Interfacial catalysis: the mechanism of phospholipase A2., Scott DL, White SP, Otwinowski Z, Yuan W, Gelb MH, Sigler PB, Science. 1990 Dec 14;250(4987):1541-6. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2274785 2274785] | ||
[[Category: Naja atra]] | [[Category: Naja atra]] | ||
| - | [[Category: Phospholipase A(2)]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Otwinowski, Z.]] | [[Category: Otwinowski, Z.]] | ||
[[Category: Scott, D L.]] | [[Category: Scott, D L.]] | ||
[[Category: Sigler, P B.]] | [[Category: Sigler, P B.]] | ||
| - | [[Category: | + | [[Category: Hydrolase]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 05:18:15 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 02:18, 3 May 2008
INTERFACIAL CATALYSIS: THE MECHANISM OF PHOSPHOLIPASE A2
Overview
A chemical description of the action of phospholipase A2 (PLA2) can now be inferred with confidence from three high-resolution x-ray crystal structures. The first is the structure of the PLA2 from the venom of the Chinese cobra (Naja naja atra) in a complex with a phosphonate transition-state analogue. This enzyme is typical of a large, well-studied homologous family of PLA2S. The second is a similar complex with the evolutionarily distant bee-venom PLA2. The third structure is the uninhibited PLA2 from Chinese cobra venom. Despite the different molecular architectures of the cobra and bee-venom PLA2s, the transition-state analogue interacts in a nearly identical way with the catalytic machinery of both enzymes. The disposition of the fatty-acid side chains suggests a common access route of the substrate from its position in the lipid aggregate to its productive interaction with the active site. Comparison of the cobra-venom complex with the uninhibited enzyme indicates that optimal binding and catalysis at the lipid-water interface is due to facilitated substrate diffusion from the interfacial binding surface to the catalytic site rather than an allosteric change in the enzyme's structure. However, a second bound calcium ion changes its position upon the binding of the transition-state analogue, suggesting a mechanism for augmenting the critical electrophile.
About this Structure
1POA is a Single protein structure of sequence from Naja atra. Full crystallographic information is available from OCA.
Reference
Interfacial catalysis: the mechanism of phospholipase A2., Scott DL, White SP, Otwinowski Z, Yuan W, Gelb MH, Sigler PB, Science. 1990 Dec 14;250(4987):1541-6. PMID:2274785 Page seeded by OCA on Sat May 3 05:18:15 2008
