View source for 2aiq

[[Image:2aiq.gif|left|200px]]<br /><applet load="2aiq" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="2aiq, resolution 1.54&Aring;" />
'''Crystal structure of benzamidine-inhibited protein C activator from the venom of copperhead snake Agkistrodon contortrix contortrix'''<br />

==Overview==
Protein C activation initiated by the thrombin-thrombomodulin complex, forms the major physiological anticoagulant pathway. Agkistrodon, contortrix contortrix protein C activator, a glycosylated single-chain, serine proteinase, activates protein C without relying on thrombomodulin., The crystal structures of native and inhibited Agkistrodon contortrix, contortrix protein C activator determined at 1.65 and 1.54 A resolutions, respectively, indicate the pivotal roles played by the positively charged, belt and the strategic positioning of the three carbohydrate moieties, surrounding the catalytic site in protein C recognition, binding, and, activation. Structural changes in the benzamidine-inhibited enzyme suggest, a probable function in allosteric regulation for the anion-binding site, located in the C-terminal extension, which is fully conserved in snake, venom serine proteinases, that preferentially binds Cl(1-) instead of, SO(4)(2-).

==About this Structure==
2AIQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Agkistrodon_contortrix_contortrix Agkistrodon contortrix contortrix] with NAG, NDG, SO4, ACT, CL, BEN and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Venombin_A Venombin A], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.74 3.4.21.74] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2AIQ OCA]. 

==Reference==
Thrombomodulin-independent activation of protein C and specificity of hemostatically active snake venom serine proteinases: crystal structures of native and inhibited Agkistrodon contortrix contortrix protein C activator., Murakami MT, Arni RK, J Biol Chem. 2005 Nov 25;280(47):39309-15. Epub 2005 Sep 14. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16162508 16162508]
[[Category: Agkistrodon contortrix contortrix]]
[[Category: Single protein]]
[[Category: Venombin A]]
[[Category: Arni, R.K.]]
[[Category: Murakami, M.T.]]
[[Category: ACT]]
[[Category: BEN]]
[[Category: CL]]
[[Category: GOL]]
[[Category: NAG]]
[[Category: NDG]]
[[Category: SO4]]
[[Category: protein c activator]]
[[Category: snake venom serine proteinase]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 08:09:01 2007''