1l1j
From Proteopedia
(New page: 200px<br /><applet load="1l1j" size="450" color="white" frame="true" align="right" spinBox="true" caption="1l1j, resolution 2.8Å" /> '''Crystal structure of ...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1l1j.jpg|left|200px]]<br /><applet load="1l1j" size=" | + | [[Image:1l1j.jpg|left|200px]]<br /><applet load="1l1j" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1l1j, resolution 2.8Å" /> | caption="1l1j, resolution 2.8Å" /> | ||
'''Crystal structure of the protease domain of an ATP-independent heat shock protease HtrA'''<br /> | '''Crystal structure of the protease domain of an ATP-independent heat shock protease HtrA'''<br /> | ||
==Overview== | ==Overview== | ||
| - | HtrA (high temperature requirement A), a periplasmic heat-shock protein, functions as a molecular chaperone at low temperatures, and its | + | HtrA (high temperature requirement A), a periplasmic heat-shock protein, functions as a molecular chaperone at low temperatures, and its proteolytic activity is turned on at elevated temperatures. To investigate the mechanism of functional switch to protease, we determined the crystal structure of the NH(2)-terminal protease domain (PD) of HtrA from Thermotoga maritima, which was shown to retain both proteolytic and chaperone-like activities. Three subunits of HtrA PD compose a trimer, and multimerization architecture is similar to that found in the crystal structures of intact HtrA hexamer from Escherichia coli and human HtrA2 trimer. HtrA PD shares the same fold with chymotrypsin-like serine proteases, but it contains an additional lid that blocks access the of substrates to the active site. A corresponding lid found in E. coli HtrA is a long loop that also blocks the active site of another subunit. These results suggest that the activation of the proteolytic function of HtrA at elevated temperatures might occur by a conformational change, which includes the opening of the helical lid to expose the active site and subsequent rearrangement of a catalytic triad and an oxyanion hole. |
==About this Structure== | ==About this Structure== | ||
| - | 1L1J is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima]. Full crystallographic information is available from [http:// | + | 1L1J is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1L1J OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Thermotoga maritima]] | [[Category: Thermotoga maritima]] | ||
| - | [[Category: Ha, S | + | [[Category: Ha, S C.]] |
| - | [[Category: Hwang, H | + | [[Category: Hwang, H Y.]] |
| - | [[Category: Kim, D | + | [[Category: Kim, D R.]] |
| - | [[Category: Kim, D | + | [[Category: Kim, D Y.]] |
| - | [[Category: Kim, K | + | [[Category: Kim, K K.]] |
| - | [[Category: Lokanath, N | + | [[Category: Lokanath, N K.]] |
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
[[Category: serine proteinase]] | [[Category: serine proteinase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:40:17 2008'' |
Revision as of 11:40, 21 February 2008
|
Crystal structure of the protease domain of an ATP-independent heat shock protease HtrA
Overview
HtrA (high temperature requirement A), a periplasmic heat-shock protein, functions as a molecular chaperone at low temperatures, and its proteolytic activity is turned on at elevated temperatures. To investigate the mechanism of functional switch to protease, we determined the crystal structure of the NH(2)-terminal protease domain (PD) of HtrA from Thermotoga maritima, which was shown to retain both proteolytic and chaperone-like activities. Three subunits of HtrA PD compose a trimer, and multimerization architecture is similar to that found in the crystal structures of intact HtrA hexamer from Escherichia coli and human HtrA2 trimer. HtrA PD shares the same fold with chymotrypsin-like serine proteases, but it contains an additional lid that blocks access the of substrates to the active site. A corresponding lid found in E. coli HtrA is a long loop that also blocks the active site of another subunit. These results suggest that the activation of the proteolytic function of HtrA at elevated temperatures might occur by a conformational change, which includes the opening of the helical lid to expose the active site and subsequent rearrangement of a catalytic triad and an oxyanion hole.
About this Structure
1L1J is a Single protein structure of sequence from Thermotoga maritima. Full crystallographic information is available from OCA.
Reference
Crystal structure of the protease domain of a heat-shock protein HtrA from Thermotoga maritima., Kim DY, Kim DR, Ha SC, Lokanath NK, Lee CJ, Hwang HY, Kim KK, J Biol Chem. 2003 Feb 21;278(8):6543-51. Epub 2002 Nov 27. PMID:12458220
Page seeded by OCA on Thu Feb 21 13:40:17 2008
