1dlk
From Proteopedia
(New page: 200px<br /><applet load="1dlk" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dlk, resolution 2.14Å" /> '''CRYSTAL STRUCTURE AN...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1dlk.gif|left|200px]]<br /><applet load="1dlk" size=" | + | [[Image:1dlk.gif|left|200px]]<br /><applet load="1dlk" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dlk, resolution 2.14Å" /> | caption="1dlk, resolution 2.14Å" /> | ||
'''CRYSTAL STRUCTURE ANALYSIS OF DELTA-CHYMOTRYPSIN BOUND TO A PEPTIDYL CHLOROMETHYL KETONE INHIBITOR'''<br /> | '''CRYSTAL STRUCTURE ANALYSIS OF DELTA-CHYMOTRYPSIN BOUND TO A PEPTIDYL CHLOROMETHYL KETONE INHIBITOR'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Chymotrypsin is a member of the trypsin family of serine proteases and is | + | Chymotrypsin is a member of the trypsin family of serine proteases and is one of the first proteins successfully studied by X-ray crystallography. It is secreted into the intestine as the inactive precursor chymotrypsinogen; four sequential cleavages of the peptide bonds following residues 13, 15, 146 and 148 occur to generate the active pi, delta, kappa and alpha forms of chymotrypsin. (13)C NMR has shown [O'Connell & Malthouse (1995). Biochem. J. 307, 353-359] that when the delta form of chymotrypsin is inhibited by 2-(13)C-enriched benzyloxycarbonylglycylglycylphenylalanyl chloromethane, a tetrahedral adduct is formed which is thought to be analogous to the tetrahedral intermediate formed during catalysis. This inhibitor complex has been crystallized as a dimer in space group P4(1)2(1)2. The structure has been refined at 2.14 A resolution to an R value of 21.2% (free R = 25.2%). Conformational differences between delta-chymotrypsin and chymotrypsinogen in the region of the flexible autolysis loop (residues 145-150) were observed. This is the first crystal structure of delta-chymotrypsin and includes two residues which are disordered in previous crystal structures of active chymotrypsin. A difference of 11.3 A(2) between the average B values of the monomers within the asymmetric unit is caused by lattice-disordering effects approximating to rotation of the molecules about a crystallographic screw axis. The substrate-binding mode of the inhibitor was similar to other chymotrypsin peptidyl inhibitor complexes, but this is the first published chymotrypsin structure in which the tetrahedral chloromethyl ketone transition-state analogue is observed. This structure is compared with that of a similar tetrahedral transition-state analogue which does not alkylate the active-site histidine residue. |
==About this Structure== | ==About this Structure== | ||
| - | 1DLK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with CL, GLY and BGG as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Chymotrypsin Chymotrypsin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.1 3.4.21.1] Full crystallographic information is available from [http:// | + | 1DLK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=GLY:'>GLY</scene> and <scene name='pdbligand=BGG:'>BGG</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Chymotrypsin Chymotrypsin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.1 3.4.21.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DLK OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 15: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Birrane, G.]] | [[Category: Birrane, G.]] | ||
| - | [[Category: Connell, T | + | [[Category: Connell, T O.]] |
| - | [[Category: Malthouse, J | + | [[Category: Malthouse, J P.G.]] |
| - | [[Category: Sweeney, A | + | [[Category: Sweeney, A Mac.]] |
| - | [[Category: Walsh, M | + | [[Category: Walsh, M A.]] |
[[Category: BGG]] | [[Category: BGG]] | ||
[[Category: CL]] | [[Category: CL]] | ||
| Line 26: | Line 26: | ||
[[Category: peptidic inhibior]] | [[Category: peptidic inhibior]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:17:50 2008'' |
Revision as of 10:17, 21 February 2008
|
CRYSTAL STRUCTURE ANALYSIS OF DELTA-CHYMOTRYPSIN BOUND TO A PEPTIDYL CHLOROMETHYL KETONE INHIBITOR
Overview
Chymotrypsin is a member of the trypsin family of serine proteases and is one of the first proteins successfully studied by X-ray crystallography. It is secreted into the intestine as the inactive precursor chymotrypsinogen; four sequential cleavages of the peptide bonds following residues 13, 15, 146 and 148 occur to generate the active pi, delta, kappa and alpha forms of chymotrypsin. (13)C NMR has shown [O'Connell & Malthouse (1995). Biochem. J. 307, 353-359] that when the delta form of chymotrypsin is inhibited by 2-(13)C-enriched benzyloxycarbonylglycylglycylphenylalanyl chloromethane, a tetrahedral adduct is formed which is thought to be analogous to the tetrahedral intermediate formed during catalysis. This inhibitor complex has been crystallized as a dimer in space group P4(1)2(1)2. The structure has been refined at 2.14 A resolution to an R value of 21.2% (free R = 25.2%). Conformational differences between delta-chymotrypsin and chymotrypsinogen in the region of the flexible autolysis loop (residues 145-150) were observed. This is the first crystal structure of delta-chymotrypsin and includes two residues which are disordered in previous crystal structures of active chymotrypsin. A difference of 11.3 A(2) between the average B values of the monomers within the asymmetric unit is caused by lattice-disordering effects approximating to rotation of the molecules about a crystallographic screw axis. The substrate-binding mode of the inhibitor was similar to other chymotrypsin peptidyl inhibitor complexes, but this is the first published chymotrypsin structure in which the tetrahedral chloromethyl ketone transition-state analogue is observed. This structure is compared with that of a similar tetrahedral transition-state analogue which does not alkylate the active-site histidine residue.
About this Structure
1DLK is a Single protein structure of sequence from Bos taurus with , and as ligands. Active as Chymotrypsin, with EC number 3.4.21.1 Full crystallographic information is available from OCA.
Reference
Crystal structure of delta-chymotrypsin bound to a peptidyl chloromethyl ketone inhibitor., Mac Sweeney A, Birrane G, Walsh MA, O'Connell T, Malthouse JP, Higgins TM, Acta Crystallogr D Biol Crystallogr. 2000 Mar;56(Pt 3):280-6. PMID:10713514
Page seeded by OCA on Thu Feb 21 12:17:50 2008
