1djx: Difference between revisions

Revision as of 13:56, 2 May 2008

PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE C-DELTA1 FROM RAT COMPLEXED WITH INOSITOL-1,4,5-TRISPHOSPHATE

OverviewOverview

The crystal structures of various ternary complexes of phosphoinositide-specific phospholipase C-delta 1 from rat with calcium and inositol phosphates have been determined at 2.30-2.95 A resolution. The inositol phosphates used in this study mimic the binding of substrates and the reaction intermediate and include D-myo-inositol-1,4,5-trisphosphate, D-myo-inositol-2,4, 5-trisphosphate. D-myo-inositol-4,5-bisphosphate, and D,1-myo-inositol-2-methylene-1,2-cyclicmonophosphonate. The complexes exhibit an almost invariant mode of binding in the active site, each fitting edge-on into the active site and interacting with both the enzyme and the catalytic calcium at the bottom of the active site. Most of the active site residues do not undergo conformational changes upon binding either calcium or inositol phosphates. The structures are consistent with bidentate liganding of the catalytic calcium to the inositol phosphate intermediate and transition state. The complexes suggest explanations for substrate preference, pH optima, and ratio of cyclic to acyclic reaction products. A reaction mechanism is derived that supports general acid/base catalysis in a sequential mechanism involving a cyclic phosphate intermediate and rules out a parallel mechanism where acyclic and cyclic products are simultaneously generated.

About this StructureAbout this Structure

1DJX is a Single protein structure of sequence from Rattus norvegicus. Full crystallographic information is available from OCA.

ReferenceReference

Structural mapping of the catalytic mechanism for a mammalian phosphoinositide-specific phospholipase C., Essen LO, Perisic O, Katan M, Wu Y, Roberts MF, Williams RL, Biochemistry. 1997 Feb 18;36(7):1704-18. PMID:9048554 Page seeded by OCA on Fri May 2 13:56:03 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

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 [[Image:1djx.gif|left|200px]]
- {{Structure
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+The line below this paragraph, containing "STRUCTURE_1djx", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=I3P:D-MYO-INOSITOL-1,4,5-TRIPHOSPHATE'>I3P</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Phosphoinositide_phospholipase_C Phosphoinositide phospholipase C], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.4.11 3.1.4.11] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE= CDNA FRAGMENT ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=10116 Rattus norvegicus])
+-->
-|DOMAIN=
+{{STRUCTURE_1djx|  PDB=1djx  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1djx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1djx OCA], [http://www.ebi.ac.uk/pdbsum/1djx PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1djx RCSB]</span>
-}}
 '''PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE C-DELTA1 FROM RAT COMPLEXED WITH INOSITOL-1,4,5-TRISPHOSPHATE'''
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 [[Category: Perisic, O.]]
 [[Category: Williams, R L.]]
-[[Category: calcium-binding]]
+[[Category: Calcium-binding]]
-[[Category: hydrolase]]
+[[Category: Hydrolase]]
-[[Category: lipid degradation]]
+[[Category: Lipid degradation]]
-[[Category: phosphoinositide-specific]]
+[[Category: Phosphoinositide-specific]]
-[[Category: phospholipase c]]
+[[Category: Phospholipase c]]
-[[Category: phosphoric diester hydrolase]]
+[[Category: Phosphoric diester hydrolase]]
-[[Category: transducer]]
+[[Category: Transducer]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 13:56:03 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:43:03 2008''