1ptd
From Proteopedia
(New page: 200px<br /><applet load="1ptd" size="450" color="white" frame="true" align="right" spinBox="true" caption="1ptd, resolution 2.6Å" /> '''PHOSPHATIDYLINOSITOL-...) |
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| - | [[Image:1ptd.jpg|left|200px]]<br /><applet load="1ptd" size=" | + | [[Image:1ptd.jpg|left|200px]]<br /><applet load="1ptd" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1ptd, resolution 2.6Å" /> | caption="1ptd, resolution 2.6Å" /> | ||
'''PHOSPHATIDYLINOSITOL-SPECIFIC PHOSPHOLIPASE C'''<br /> | '''PHOSPHATIDYLINOSITOL-SPECIFIC PHOSPHOLIPASE C'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Phosphatidylinositol (PI), once regarded as an obscure component of | + | Phosphatidylinositol (PI), once regarded as an obscure component of membranes, is now recognized as an important reservoir of second messenger precursors and as an anchor for membrane enzymes. PI-specific phospholipase C (PI-PLC) is the enzyme that cleaves PI, invoking numerous cellular responses. The crystal structure of PI-PLC from Bacillus cereus (EC 3.1.4.10) has been solved at 2.6 A resolution and refined to a crystallographic R factor of 18.7%. The structure consists of an imperfect (beta alpha)8-barrel similar to that first observed for triose phosphate isomerase and does not resemble any other known phospholipase structure. The active site of the enzyme has been identified by determining the structure of PI-PLC in complex with its inhibitor, myo-inositol, at 2.6 A resolution (R factor = 19.5%). This substrate-like inhibitor interacts with a number of residues highly conserved among prokaryotic PI-PLCs. Residues His32 and His82, which are also conserved between prokaryotic and eukaryotic PI-PLCs, most likely act as general base and acid respectively in a catalytic mechanism analogous to that observed for ribonucleases. |
==About this Structure== | ==About this Structure== | ||
| - | 1PTD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_cereus Bacillus cereus]. Active as [http://en.wikipedia.org/wiki/Phosphatidylinositol_diacylglycerol-lyase Phosphatidylinositol diacylglycerol-lyase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.6.1.13 4.6.1.13] Full crystallographic information is available from [http:// | + | 1PTD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_cereus Bacillus cereus]. Active as [http://en.wikipedia.org/wiki/Phosphatidylinositol_diacylglycerol-lyase Phosphatidylinositol diacylglycerol-lyase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.6.1.13 4.6.1.13] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PTD OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Phosphatidylinositol diacylglycerol-lyase]] | [[Category: Phosphatidylinositol diacylglycerol-lyase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Bullock, T | + | [[Category: Bullock, T L.]] |
| - | [[Category: Griffith, O | + | [[Category: Griffith, O H.]] |
| - | [[Category: Heinz, D | + | [[Category: Heinz, D W.]] |
[[Category: Ryan, M.]] | [[Category: Ryan, M.]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
[[Category: phosphatidylinositol specific phospholipase c]] | [[Category: phosphatidylinositol specific phospholipase c]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:32:23 2008'' |
Revision as of 12:32, 21 February 2008
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PHOSPHATIDYLINOSITOL-SPECIFIC PHOSPHOLIPASE C
Overview
Phosphatidylinositol (PI), once regarded as an obscure component of membranes, is now recognized as an important reservoir of second messenger precursors and as an anchor for membrane enzymes. PI-specific phospholipase C (PI-PLC) is the enzyme that cleaves PI, invoking numerous cellular responses. The crystal structure of PI-PLC from Bacillus cereus (EC 3.1.4.10) has been solved at 2.6 A resolution and refined to a crystallographic R factor of 18.7%. The structure consists of an imperfect (beta alpha)8-barrel similar to that first observed for triose phosphate isomerase and does not resemble any other known phospholipase structure. The active site of the enzyme has been identified by determining the structure of PI-PLC in complex with its inhibitor, myo-inositol, at 2.6 A resolution (R factor = 19.5%). This substrate-like inhibitor interacts with a number of residues highly conserved among prokaryotic PI-PLCs. Residues His32 and His82, which are also conserved between prokaryotic and eukaryotic PI-PLCs, most likely act as general base and acid respectively in a catalytic mechanism analogous to that observed for ribonucleases.
About this Structure
1PTD is a Single protein structure of sequence from Bacillus cereus. Active as Phosphatidylinositol diacylglycerol-lyase, with EC number 4.6.1.13 Full crystallographic information is available from OCA.
Reference
Crystal structure of the phosphatidylinositol-specific phospholipase C from Bacillus cereus in complex with myo-inositol., Heinz DW, Ryan M, Bullock TL, Griffith OH, EMBO J. 1995 Aug 15;14(16):3855-63. PMID:7664726
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