4cha
From Proteopedia
(New page: 200px<br /><applet load="4cha" size="450" color="white" frame="true" align="right" spinBox="true" caption="4cha, resolution 1.68Å" /> '''STRUCTURE OF ALPHA-*...) |
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| - | [[Image:4cha.gif|left|200px]]<br /><applet load="4cha" size=" | + | [[Image:4cha.gif|left|200px]]<br /><applet load="4cha" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="4cha, resolution 1.68Å" /> | caption="4cha, resolution 1.68Å" /> | ||
'''STRUCTURE OF ALPHA-*CHYMOTRYPSIN REFINED AT 1.68 ANGSTROMS RESOLUTION'''<br /> | '''STRUCTURE OF ALPHA-*CHYMOTRYPSIN REFINED AT 1.68 ANGSTROMS RESOLUTION'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Diffraction data for alpha-chymotrypsin crystals at -10 degrees C were | + | Diffraction data for alpha-chymotrypsin crystals at -10 degrees C were measured at 1.68 A resolution and refined by restrained structure-factor least-squares refinement. The two independent chymotrypsin molecules in the crystallographic asymmetric unit were refined independently. The overall structure of alpha-chymotrypsin is little changed from published co-ordinates. The root-mean-square shift of C alpha co-ordinates is 0.42 A, co-ordinates for the two molecules showing a root-mean-square difference of 0.19 A. Certain regions with high disorder (residues 9 to 14, 73 to 79) remain difficult to interpret and several side-chains are disordered. Some water molecule positions have been changed. The absence of the tosyl group has made a significant difference to the refined structure at the active site. This now agrees closely with other enzymes of the trypsin family that have been refined at high resolution. There is a strong hydrogen bond between N epsilon 2 (His57) and O gamma (Ser195) in the free enzyme, in line with the published description of the charge relay system. |
==About this Structure== | ==About this Structure== | ||
| - | 4CHA is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. 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:// | + | 4CHA is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. 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=4CHA OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Chymotrypsin]] | [[Category: Chymotrypsin]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Blow, D | + | [[Category: Blow, D M.]] |
[[Category: Tsukada, H.]] | [[Category: Tsukada, H.]] | ||
[[Category: hydrolase (serine proteinase)]] | [[Category: hydrolase (serine proteinase)]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:12:55 2008'' |
Revision as of 17:12, 21 February 2008
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STRUCTURE OF ALPHA-*CHYMOTRYPSIN REFINED AT 1.68 ANGSTROMS RESOLUTION
Overview
Diffraction data for alpha-chymotrypsin crystals at -10 degrees C were measured at 1.68 A resolution and refined by restrained structure-factor least-squares refinement. The two independent chymotrypsin molecules in the crystallographic asymmetric unit were refined independently. The overall structure of alpha-chymotrypsin is little changed from published co-ordinates. The root-mean-square shift of C alpha co-ordinates is 0.42 A, co-ordinates for the two molecules showing a root-mean-square difference of 0.19 A. Certain regions with high disorder (residues 9 to 14, 73 to 79) remain difficult to interpret and several side-chains are disordered. Some water molecule positions have been changed. The absence of the tosyl group has made a significant difference to the refined structure at the active site. This now agrees closely with other enzymes of the trypsin family that have been refined at high resolution. There is a strong hydrogen bond between N epsilon 2 (His57) and O gamma (Ser195) in the free enzyme, in line with the published description of the charge relay system.
About this Structure
4CHA is a Protein complex structure of sequences from Bos taurus. Active as Chymotrypsin, with EC number 3.4.21.1 Full crystallographic information is available from OCA.
Reference
Structure of alpha-chymotrypsin refined at 1.68 A resolution., Tsukada H, Blow DM, J Mol Biol. 1985 Aug 20;184(4):703-11. PMID:4046030
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