2olg
From Proteopedia
(New page: 200px<br /><applet load="2olg" size="350" color="white" frame="true" align="right" spinBox="true" caption="2olg, resolution 1.70Å" /> '''Crystal structure of...) |
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==Overview== | ==Overview== | ||
| - | A family of serine proteases (SPs) mediates the proteolytic cascades of | + | A family of serine proteases (SPs) mediates the proteolytic cascades of embryonic development and immune response in invertebrates. These proteases, called easter-type SPs, consist of clip and chymotrypsin-like SP domains. The SP domain of easter-type proteases differs from those of typical SPs in its primary structure. Herein, we report the first crystal structure of the SP domain of easter-type proteases, presented as that of prophenoloxidase activating factor (PPAF)-I in zymogen form. This structure reveals several important structural features including a bound calcium ion, an additional loop with a unique disulfide linkage, a canyon-like deep active site, and an exposed activation loop. We subsequently show the role of the bound calcium and the proteolytic susceptibility of the activation loop, which occurs in a clip domain-independent manner. Based on biochemical study in the presence of heparin, we suggest that PPAF-III, highly homologous to PPAF-I, contains a surface patch that is responsible for enhancing the catalytic activity through interaction with a nonsubstrate region of a target protein. These results provide insights into an activation mechanism of easter-type proteases in proteolytic cascades, in comparison with the well studied blood coagulation enzymes in mammals. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | Crystal structure of the serine protease domain of prophenoloxidase activating factor-I., Piao S, Kim S, Kim JH, Park JW, Lee BL, Ha NC, J Biol Chem. 2007 Apr | + | Crystal structure of the serine protease domain of prophenoloxidase activating factor-I., Piao S, Kim S, Kim JH, Park JW, Lee BL, Ha NC, J Biol Chem. 2007 Apr;282(14):10783-91. Epub 2007 Feb 7. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17287215 17287215] |
[[Category: Holotrichia diomphalia]] | [[Category: Holotrichia diomphalia]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Ha, N | + | [[Category: Ha, N C.]] |
[[Category: Piao, S.]] | [[Category: Piao, S.]] | ||
[[Category: CA]] | [[Category: CA]] | ||
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[[Category: serine protease]] | [[Category: serine protease]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:19:47 2008'' |
Revision as of 16:19, 21 February 2008
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Crystal structure of the serine protease domain of prophenoloxidase activating factor-I in a zymogen form
Overview
A family of serine proteases (SPs) mediates the proteolytic cascades of embryonic development and immune response in invertebrates. These proteases, called easter-type SPs, consist of clip and chymotrypsin-like SP domains. The SP domain of easter-type proteases differs from those of typical SPs in its primary structure. Herein, we report the first crystal structure of the SP domain of easter-type proteases, presented as that of prophenoloxidase activating factor (PPAF)-I in zymogen form. This structure reveals several important structural features including a bound calcium ion, an additional loop with a unique disulfide linkage, a canyon-like deep active site, and an exposed activation loop. We subsequently show the role of the bound calcium and the proteolytic susceptibility of the activation loop, which occurs in a clip domain-independent manner. Based on biochemical study in the presence of heparin, we suggest that PPAF-III, highly homologous to PPAF-I, contains a surface patch that is responsible for enhancing the catalytic activity through interaction with a nonsubstrate region of a target protein. These results provide insights into an activation mechanism of easter-type proteases in proteolytic cascades, in comparison with the well studied blood coagulation enzymes in mammals.
About this Structure
2OLG is a Single protein structure of sequence from Holotrichia diomphalia with , and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of the serine protease domain of prophenoloxidase activating factor-I., Piao S, Kim S, Kim JH, Park JW, Lee BL, Ha NC, J Biol Chem. 2007 Apr;282(14):10783-91. Epub 2007 Feb 7. PMID:17287215
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