1lpb: Difference between revisions
New page: left|200px<br /> <applet load="1lpb" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lpb, resolution 2.46Å" /> '''THE 2.46 ANGSTROMS ... |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1lpb.gif|left|200px]]<br /> | [[Image:1lpb.gif|left|200px]]<br /><applet load="1lpb" size="350" color="white" frame="true" align="right" spinBox="true" | ||
<applet load="1lpb" size=" | |||
caption="1lpb, resolution 2.46Å" /> | caption="1lpb, resolution 2.46Å" /> | ||
'''THE 2.46 ANGSTROMS RESOLUTION STRUCTURE OF THE PANCREATIC LIPASE COLIPASE COMPLEX INHIBITED BY A C11 ALKYL PHOSPHONATE'''<br /> | '''THE 2.46 ANGSTROMS RESOLUTION STRUCTURE OF THE PANCREATIC LIPASE COLIPASE COMPLEX INHIBITED BY A C11 ALKYL PHOSPHONATE'''<br /> | ||
==Overview== | ==Overview== | ||
Pancreatic lipase belongs to the serine esterase family and can therefore | Pancreatic lipase belongs to the serine esterase family and can therefore be inhibited by classical serine reagents such as diisopropyl fluoride or E600. In an attempt to further characterize the active site and catalytic mechanism, we synthesized a C11 alkyl phosphonate compound. This compound is an effective inhibitor of pancreatic lipase. The crystal structure of the pancreatic lipase-colipase complex inhibited by this compound was determined at a resolution of 2.46 A and refined to a final R-factor of 18.3%. As was observed in the case of the structure of the ternary pancreatic lipase-colipase-phospholipid complex, the binding of the ligand induces rearrangements of two surface loops in comparison with the closed structure of the enzyme (van Tilbeurgh et al., 1993b). The inhibitor, which could be clearly observed in the active site, was covalently bound to the active site serine Ser152. A racemic mixture of the inhibitor was used in the crystallization, and there exists evidence that both enantiomers are bound at the active site. The C11 alkyl chain of the first enantiomer fits into a hydrophobic groove and is though to thus mimic the interaction between the leaving fatty acid of a triglyceride substrate and the protein. The alkyl chain of the second enantiomer also has an elongated conformation and interacts with hydrophobic patches on the surface of the open amphipathic lid. This may indicate the location of a second alkyl chain of a triglyceride substrate. Some of the detergent molecules, needed for the crystallization, were also observed in the crystal. Some of them were located at the entrance of the active site, bound to the hydrophobic part of the lid. On the basis of this crystallographic study, a hypothesis about the binding mode of real substrates and the organization of the active site is proposed. | ||
==Disease== | ==Disease== | ||
| Line 11: | Line 10: | ||
==About this Structure== | ==About this Structure== | ||
1LPB is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with BOG, CA and MUP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Triacylglycerol_lipase Triacylglycerol lipase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.3 3.1.1.3] Full crystallographic information is available from [http:// | 1LPB is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with <scene name='pdbligand=BOG:'>BOG</scene>, <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=MUP:'>MUP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Triacylglycerol_lipase Triacylglycerol lipase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.3 3.1.1.3] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LPB OCA]. | ||
==Reference== | ==Reference== | ||
| Line 20: | Line 19: | ||
[[Category: Triacylglycerol lipase]] | [[Category: Triacylglycerol lipase]] | ||
[[Category: Cambillau, C.]] | [[Category: Cambillau, C.]] | ||
[[Category: Egloff, M | [[Category: Egloff, M P.]] | ||
[[Category: Tilbeurgh, H | [[Category: Tilbeurgh, H Van.]] | ||
[[Category: BOG]] | [[Category: BOG]] | ||
[[Category: CA]] | [[Category: CA]] | ||
| Line 27: | Line 26: | ||
[[Category: hydrolase(carboxylic esterase)]] | [[Category: hydrolase(carboxylic esterase)]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:47:09 2008'' | ||
Revision as of 14:47, 21 February 2008
|
THE 2.46 ANGSTROMS RESOLUTION STRUCTURE OF THE PANCREATIC LIPASE COLIPASE COMPLEX INHIBITED BY A C11 ALKYL PHOSPHONATE
OverviewOverview
Pancreatic lipase belongs to the serine esterase family and can therefore be inhibited by classical serine reagents such as diisopropyl fluoride or E600. In an attempt to further characterize the active site and catalytic mechanism, we synthesized a C11 alkyl phosphonate compound. This compound is an effective inhibitor of pancreatic lipase. The crystal structure of the pancreatic lipase-colipase complex inhibited by this compound was determined at a resolution of 2.46 A and refined to a final R-factor of 18.3%. As was observed in the case of the structure of the ternary pancreatic lipase-colipase-phospholipid complex, the binding of the ligand induces rearrangements of two surface loops in comparison with the closed structure of the enzyme (van Tilbeurgh et al., 1993b). The inhibitor, which could be clearly observed in the active site, was covalently bound to the active site serine Ser152. A racemic mixture of the inhibitor was used in the crystallization, and there exists evidence that both enantiomers are bound at the active site. The C11 alkyl chain of the first enantiomer fits into a hydrophobic groove and is though to thus mimic the interaction between the leaving fatty acid of a triglyceride substrate and the protein. The alkyl chain of the second enantiomer also has an elongated conformation and interacts with hydrophobic patches on the surface of the open amphipathic lid. This may indicate the location of a second alkyl chain of a triglyceride substrate. Some of the detergent molecules, needed for the crystallization, were also observed in the crystal. Some of them were located at the entrance of the active site, bound to the hydrophobic part of the lid. On the basis of this crystallographic study, a hypothesis about the binding mode of real substrates and the organization of the active site is proposed.
DiseaseDisease
Known disease associated with this structure: Pancreatic lipase deficiency OMIM:[246600]
About this StructureAbout this Structure
1LPB is a Protein complex structure of sequences from Homo sapiens and Sus scrofa with , and as ligands. Active as Triacylglycerol lipase, with EC number 3.1.1.3 Full crystallographic information is available from OCA.
ReferenceReference
The 2.46 A resolution structure of the pancreatic lipase-colipase complex inhibited by a C11 alkyl phosphonate., Egloff MP, Marguet F, Buono G, Verger R, Cambillau C, van Tilbeurgh H, Biochemistry. 1995 Mar 7;34(9):2751-62. PMID:7893686
Page seeded by OCA on Thu Feb 21 13:47:09 2008