1clp
From Proteopedia
(New page: 200px<br /><applet load="1clp" size="450" color="white" frame="true" align="right" spinBox="true" caption="1clp, resolution 2.8Å" /> '''CRYSTAL STRUCTURE OF ...) |
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| - | [[Image:1clp.gif|left|200px]]<br /><applet load="1clp" size=" | + | [[Image:1clp.gif|left|200px]]<br /><applet load="1clp" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1clp, resolution 2.8Å" /> | caption="1clp, resolution 2.8Å" /> | ||
'''CRYSTAL STRUCTURE OF A CALCIUM-INDEPENDENT PHOSPHOLIPASELIKE MYOTOXIC PROTEIN FROM BOTHROPS ASPER VENOM'''<br /> | '''CRYSTAL STRUCTURE OF A CALCIUM-INDEPENDENT PHOSPHOLIPASELIKE MYOTOXIC PROTEIN FROM BOTHROPS ASPER VENOM'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Myotoxin II, a myotoxic calcium-independent phospholipase-like protein | + | Myotoxin II, a myotoxic calcium-independent phospholipase-like protein isolated from the venom of Bothrops asper, possesses no detectable phospholipase activity. The crystal structure has been determined and refined at 2.8 A to an R-factor of 16.5% (F > 3sigma) with excellent stereochemistry. Amino-acid differences between catalytically active phospholipases and myotoxin II in the Ca(2+)-binding region, specifically the substitutions Tyr28-->Asn, Gly32-->Leu and Asp49-->Lys, result in an altered local conformation. The key difference is that the epsilon-amino group of Lys49 fills the site normally occupied by the calcium ion in catalytically active phospholipases. In contrast to the homologous monomeric Lys49 variant from Agkistrodon piscivorus piscivorus, myotoxin II is present as a dimer both in solution and in the crystalline state. The two molecules in the asymmetric unit are related by a nearly perfect twofold axis, yet the dimer is radically different from the dimer formed by the phospholipase from Crotalus atrox. Whereas in C. atrox the dimer interface occludes the active sites, in myotoxin II they are exposed to solvent. |
==About this Structure== | ==About this Structure== | ||
| - | 1CLP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bothrops_asper Bothrops asper]. Active as [http://en.wikipedia.org/wiki/Phospholipase_A(2) Phospholipase A(2)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.4 3.1.1.4] Full crystallographic information is available from [http:// | + | 1CLP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bothrops_asper Bothrops asper]. Active as [http://en.wikipedia.org/wiki/Phospholipase_A(2) Phospholipase A(2)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.4 3.1.1.4] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CLP OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Phospholipase A(2)]] | [[Category: Phospholipase A(2)]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Arni, R | + | [[Category: Arni, R K.]] |
| - | [[Category: Gutierrez, J | + | [[Category: Gutierrez, J M.]] |
[[Category: Tulinsky, A.]] | [[Category: Tulinsky, A.]] | ||
| - | [[Category: Ward, R | + | [[Category: Ward, R J.]] |
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:07:22 2008'' |
Revision as of 10:07, 21 February 2008
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CRYSTAL STRUCTURE OF A CALCIUM-INDEPENDENT PHOSPHOLIPASELIKE MYOTOXIC PROTEIN FROM BOTHROPS ASPER VENOM
Overview
Myotoxin II, a myotoxic calcium-independent phospholipase-like protein isolated from the venom of Bothrops asper, possesses no detectable phospholipase activity. The crystal structure has been determined and refined at 2.8 A to an R-factor of 16.5% (F > 3sigma) with excellent stereochemistry. Amino-acid differences between catalytically active phospholipases and myotoxin II in the Ca(2+)-binding region, specifically the substitutions Tyr28-->Asn, Gly32-->Leu and Asp49-->Lys, result in an altered local conformation. The key difference is that the epsilon-amino group of Lys49 fills the site normally occupied by the calcium ion in catalytically active phospholipases. In contrast to the homologous monomeric Lys49 variant from Agkistrodon piscivorus piscivorus, myotoxin II is present as a dimer both in solution and in the crystalline state. The two molecules in the asymmetric unit are related by a nearly perfect twofold axis, yet the dimer is radically different from the dimer formed by the phospholipase from Crotalus atrox. Whereas in C. atrox the dimer interface occludes the active sites, in myotoxin II they are exposed to solvent.
About this Structure
1CLP is a Single protein structure of sequence from Bothrops asper. Active as Phospholipase A(2), with EC number 3.1.1.4 Full crystallographic information is available from OCA.
Reference
Structure of a calcium-independent phospholipase-like myotoxic protein from Bothrops asper venom., Arni RK, Ward RJ, Gutierrez JM, Tulinsky A, Acta Crystallogr D Biol Crystallogr. 1995 May 1;51(Pt 3):311-7. PMID:15299297
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