1iu4
From Proteopedia
(New page: 200px<br /><applet load="1iu4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1iu4, resolution 2.4Å" /> '''Crystal Structure Ana...) |
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| - | [[Image:1iu4.gif|left|200px]]<br /><applet load="1iu4" size=" | + | [[Image:1iu4.gif|left|200px]]<br /><applet load="1iu4" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1iu4, resolution 2.4Å" /> | caption="1iu4, resolution 2.4Å" /> | ||
'''Crystal Structure Analysis of the Microbial Transglutaminase'''<br /> | '''Crystal Structure Analysis of the Microbial Transglutaminase'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of a microbial transglutaminase from | + | The crystal structure of a microbial transglutaminase from Streptoverticillium mobaraense has been determined at 2.4 A resolution. The protein folds into a plate-like shape, and has one deep cleft at the edge of the molecule. Its overall structure is completely different from that of the factor XIII-like transglutaminase, which possesses a cysteine protease-like catalytic triad. The catalytic residue, Cys(64), exists at the bottom of the cleft. Asp(255) resides at the position nearest to Cys(64) and is also adjacent to His(274). Interestingly, Cys(64), Asp(255), and His(274) superimpose well on the catalytic triad "Cys-His-Asp" of the factor XIII-like transglutaminase, in this order. The secondary structure frameworks around these residues are also similar to each other. These results imply that both transglutaminases are related by convergent evolution; however, the microbial transglutaminase has developed a novel catalytic mechanism specialized for the cross-linking reaction. The structure accounts well for the catalytic mechanism, in which Asp(255) is considered to be enzymatically essential, as well as for the causes of the higher reaction rate, the broader substrate specificity, and the lower deamidation activity of this enzyme. |
==About this Structure== | ==About this Structure== | ||
| - | 1IU4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_mobaraensis Streptomyces mobaraensis]. Active as [http://en.wikipedia.org/wiki/Protein-glutamine_gamma-glutamyltransferase Protein-glutamine gamma-glutamyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.2.13 2.3.2.13] Full crystallographic information is available from [http:// | + | 1IU4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_mobaraensis Streptomyces mobaraensis]. Active as [http://en.wikipedia.org/wiki/Protein-glutamine_gamma-glutamyltransferase Protein-glutamine gamma-glutamyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.2.13 2.3.2.13] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IU4 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: alpha-beta]] | [[Category: alpha-beta]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:15:38 2008'' |
Revision as of 11:15, 21 February 2008
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Crystal Structure Analysis of the Microbial Transglutaminase
Overview
The crystal structure of a microbial transglutaminase from Streptoverticillium mobaraense has been determined at 2.4 A resolution. The protein folds into a plate-like shape, and has one deep cleft at the edge of the molecule. Its overall structure is completely different from that of the factor XIII-like transglutaminase, which possesses a cysteine protease-like catalytic triad. The catalytic residue, Cys(64), exists at the bottom of the cleft. Asp(255) resides at the position nearest to Cys(64) and is also adjacent to His(274). Interestingly, Cys(64), Asp(255), and His(274) superimpose well on the catalytic triad "Cys-His-Asp" of the factor XIII-like transglutaminase, in this order. The secondary structure frameworks around these residues are also similar to each other. These results imply that both transglutaminases are related by convergent evolution; however, the microbial transglutaminase has developed a novel catalytic mechanism specialized for the cross-linking reaction. The structure accounts well for the catalytic mechanism, in which Asp(255) is considered to be enzymatically essential, as well as for the causes of the higher reaction rate, the broader substrate specificity, and the lower deamidation activity of this enzyme.
About this Structure
1IU4 is a Single protein structure of sequence from Streptomyces mobaraensis. Active as Protein-glutamine gamma-glutamyltransferase, with EC number 2.3.2.13 Full crystallographic information is available from OCA.
Reference
Crystal structure of microbial transglutaminase from Streptoverticillium mobaraense., Kashiwagi T, Yokoyama K, Ishikawa K, Ono K, Ejima D, Matsui H, Suzuki E, J Biol Chem. 2002 Nov 15;277(46):44252-60. Epub 2002 Sep 7. PMID:12221081
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