1psh: Difference between revisions

Revision as of 15:32, 21 February 2008

CRYSTAL STRUCTURE OF PHOSPHOLIPASE A2 FROM INDIAN COBRA REVEALS A TRIMERIC ASSOCIATION

OverviewOverview

Phospholipase A2 (PLA2) from Indian cobra venom (Naja naja naja) was crystallized from ethanol in space group P4(3)2(1)2 in the presence of Ca2+. The x-ray crystal structure was determined to 2.3-A resolution by molecular replacement techniques using a theoretical model constructed from homologous segments of the bovine pancreatic, porcine pancreatic, and rattlesnake venom crystal structures. The structure was refined to an R value of 0.174 for 17,542 reflections between 6.0- and 2.3-A resolution (F > 2 sigma), including 148 water molecules. The 119-amino acid enzyme has an overall architecture strikingly similar to the other known PLA2 structures with regions implicated in catalysis showing the greatest structural conservation. Unexpectedly, three monomers were found to occupy the asymmetric unit and are oriented with their catalytic sites facing the pseudo-threefold axis with approximately 15% of the solvent accessible surface of each monomer buried in trimer contacts. The majority of the interactions at the subunit interfaces are made by residues unique to PLA2 sequences from cobra and krait venoms. The possible relevance of this unique trimeric structure is considered.

About this StructureAbout this Structure

1PSH is a Single protein structure of sequence from Naja naja with as ligand. Active as Phospholipase A(2), with EC number 3.1.1.4 Full crystallographic information is available from OCA.

ReferenceReference

Crystal structure of phospholipase A2 from Indian cobra reveals a trimeric association., Fremont DH, Anderson DH, Wilson IA, Dennis EA, Xuong NH, Proc Natl Acad Sci U S A. 1993 Jan 1;90(1):342-6. PMID:8419939

Page seeded by OCA on Thu Feb 21 14:32:06 2008

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OCA

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-[[Image:1psh.gif|left|200px]]<br /><applet load="1psh" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1psh.gif|left|200px]]<br /><applet load="1psh" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1psh, resolution 2.3&Aring;" />
 '''CRYSTAL STRUCTURE OF PHOSPHOLIPASE A2 FROM INDIAN COBRA REVEALS A TRIMERIC ASSOCIATION'''<br />
 ==Overview==
-Phospholipase A2 (PLA2) from Indian cobra venom (Naja naja naja) was, crystallized from ethanol in space group P4(3)2(1)2 in the presence of, Ca2+. The x-ray crystal structure was determined to 2.3-A resolution by, molecular replacement techniques using a theoretical model constructed, from homologous segments of the bovine pancreatic, porcine pancreatic, and, rattlesnake venom crystal structures. The structure was refined to an R, value of 0.174 for 17,542 reflections between 6.0- and 2.3-A resolution (F, &gt; 2 sigma), including 148 water molecules. The 119-amino acid enzyme has, an overall architecture strikingly similar to the other known PLA2, structures with regions implicated in catalysis showing the greatest, structural conservation. Unexpectedly, three monomers were found to occupy, the asymmetric unit and are oriented with their catalytic sites facing the, pseudo-threefold axis with approximately 15% of the solvent accessible, surface of each monomer buried in trimer contacts. The majority of the, interactions at the subunit interfaces are made by residues unique to PLA2, sequences from cobra and krait venoms. The possible relevance of this, unique trimeric structure is considered.
+Phospholipase A2 (PLA2) from Indian cobra venom (Naja naja naja) was crystallized from ethanol in space group P4(3)2(1)2 in the presence of Ca2+. The x-ray crystal structure was determined to 2.3-A resolution by molecular replacement techniques using a theoretical model constructed from homologous segments of the bovine pancreatic, porcine pancreatic, and rattlesnake venom crystal structures. The structure was refined to an R value of 0.174 for 17,542 reflections between 6.0- and 2.3-A resolution (F &gt; 2 sigma), including 148 water molecules. The 119-amino acid enzyme has an overall architecture strikingly similar to the other known PLA2 structures with regions implicated in catalysis showing the greatest structural conservation. Unexpectedly, three monomers were found to occupy the asymmetric unit and are oriented with their catalytic sites facing the pseudo-threefold axis with approximately 15% of the solvent accessible surface of each monomer buried in trimer contacts. The majority of the interactions at the subunit interfaces are made by residues unique to PLA2 sequences from cobra and krait venoms. The possible relevance of this unique trimeric structure is considered.
 ==About this Structure==
-PSH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_naja Naja naja] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. 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://ispc.weizmann.ac.il/oca-bin/ocashort?id=1PSH OCA].
+PSH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_naja Naja naja] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. 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=1PSH OCA].
 ==Reference==
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 [[Category: Fremont, D.]]
 [[Category: Wilson, I.]]
-[[Category: Xuong, N.H.]]
+[[Category: Xuong, N H.]]
 [[Category: CA]]
 [[Category: carboxylic ester hydrolase]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 00:05:14 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:32:06 2008''