1td7
From Proteopedia
| |||||||
, resolution 2.50Å | |||||||
---|---|---|---|---|---|---|---|
Ligands: | and | ||||||
Activity: | Phospholipase A(2), with EC number 3.1.1.4 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
Interactions of a specific non-steroidal anti-inflammatory drug (NSAID) with group I phospholipase A2 (PLA2): Crystal structure of the complex formed between PLA2 and niflumic acid at 2.5 A resolution
Overview
Phospholipase A(2) (PLA(2); EC 3.1.3.4) catalyzes the first step of the production of proinflammatory compounds collectively known as eicosanoids. The binding of phospholipid substrates to PLA(2) occurs through a well formed hydrophobic channel. Surface plasmon resonance studies have shown that niflumic acid binds to Naja naja sagittifera PLA(2) with an affinity that corresponds to a dissociation constant (K(d)) of 4.3 x 10(-5) M. Binding studies of PLA(2) with niflumic acid were also carried out using a standard PLA(2) kit that gave an approximate binding constant, K(i), of 1.26 +/- 0.05 x 10(-6) M. Therefore, in order to establish the viability of PLA(2) as a potential target molecule for drug design against inflammation, arthritis and rheumatism, the three-dimensional structure of the complex of PLA(2) with the known anti-inflammatory agent niflumic acid [2-[3-(trifluoromethyl)anilino]nicotinic acid] has been determined at 2.5 Angstroms resolution. The structure of the complex has been refined to an R factor of 0.187. The structure determination reveals the presence of one niflumic acid molecule at the substrate-binding site of PLA(2). It shows that niflumic acid interacts with the important active-site residues His48 and Asp49 through two water molecules. It is observed that the niflumic acid molecule is completely buried in the substrate-binding hydrophobic channel. The conformations of the binding site in PLA(2) as well as that of niflumic acid are not altered upon binding. However, the orientation of the side chain of Trp19, which is located at the entry of the substrate-binding site, has changed from that found in the native PLA(2), indicating its familiar role.
About this Structure
1TD7 is a Single protein structure of sequence from Naja sagittifera. Full crystallographic information is available from OCA.
Reference
Non-steroidal anti-inflammatory drugs as potent inhibitors of phospholipase A2: structure of the complex of phospholipase A2 with niflumic acid at 2.5 Angstroms resolution., Jabeen T, Singh N, Singh RK, Sharma S, Somvanshi RK, Dey S, Singh TP, Acta Crystallogr D Biol Crystallogr. 2005 Dec;61(Pt 12):1579-86. Epub 2005, Nov 19. PMID:16301791
Page seeded by OCA on Thu Mar 20 14:16:51 2008
Categories: Naja sagittifera | Phospholipase A(2) | Single protein | Betzel, C. | Jabeen, T. | Perbandt, M. | Sharma, S. | Singh, N. | Singh, R K. | Singh, T P. | CA | NFL | Enzyme | Inhibitor | Phospholipase a2