1lf1
From Proteopedia
(New page: 200px<br /><applet load="1lf1" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lf1, resolution 1.70Å" /> '''Crystal Structure of...) |
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| - | [[Image:1lf1.gif|left|200px]]<br /><applet load="1lf1" size=" | + | [[Image:1lf1.gif|left|200px]]<br /><applet load="1lf1" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1lf1, resolution 1.70Å" /> | caption="1lf1, resolution 1.70Å" /> | ||
'''Crystal Structure of Cel5 from Alkalophilic Bacillus sp.'''<br /> | '''Crystal Structure of Cel5 from Alkalophilic Bacillus sp.'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of an alkaline Bacillus cellulase catalytic core, from glucoside hydrolase family 5, reveals a novel combination of the | + | The crystal structure of an alkaline Bacillus cellulase catalytic core, from glucoside hydrolase family 5, reveals a novel combination of the catalytic machinery of two classic textbook enzymes. The enzyme has the expected two glutamate residues in close proximity to one another in the active-site that are typical of retaining cellulases. However, the proton donor, glutamate 139 is also unexpectedly a member of a serine-histidine-glutamate catalytic triad, forming a novel combination of catalytic machineries. Structure and sequence analysis of glucoside hydrolase family 5 reveal that the triad is highly conserved, but with variations at the equivalent of the serine position. We speculate that the purpose of this novel catalytic triad is to control the protonation of the acid/base glutamate, facilitating the first step of the catalytic reaction, protonation of the substrate, by the proton donor glutamate. If correct, this will be a novel use for a catalytic triad. |
==About this Structure== | ==About this Structure== | ||
| - | 1LF1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Active as [http://en.wikipedia.org/wiki/Cellulase Cellulase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.4 3.2.1.4] Full crystallographic information is available from [http:// | + | 1LF1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Active as [http://en.wikipedia.org/wiki/Cellulase Cellulase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.4 3.2.1.4] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LF1 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bott, R.]] | [[Category: Bott, R.]] | ||
[[Category: Bricogne, G.]] | [[Category: Bricogne, G.]] | ||
| - | [[Category: Day, A | + | [[Category: Day, A G.]] |
[[Category: Power, S.]] | [[Category: Power, S.]] | ||
[[Category: Shaw, A.]] | [[Category: Shaw, A.]] | ||
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[[Category: cellulose degradation]] | [[Category: cellulose degradation]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:44:27 2008'' |
Revision as of 11:44, 21 February 2008
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Crystal Structure of Cel5 from Alkalophilic Bacillus sp.
Overview
The crystal structure of an alkaline Bacillus cellulase catalytic core, from glucoside hydrolase family 5, reveals a novel combination of the catalytic machinery of two classic textbook enzymes. The enzyme has the expected two glutamate residues in close proximity to one another in the active-site that are typical of retaining cellulases. However, the proton donor, glutamate 139 is also unexpectedly a member of a serine-histidine-glutamate catalytic triad, forming a novel combination of catalytic machineries. Structure and sequence analysis of glucoside hydrolase family 5 reveal that the triad is highly conserved, but with variations at the equivalent of the serine position. We speculate that the purpose of this novel catalytic triad is to control the protonation of the acid/base glutamate, facilitating the first step of the catalytic reaction, protonation of the substrate, by the proton donor glutamate. If correct, this will be a novel use for a catalytic triad.
About this Structure
1LF1 is a Single protein structure of sequence from Bacillus subtilis. Active as Cellulase, with EC number 3.2.1.4 Full crystallographic information is available from OCA.
Reference
A novel combination of two classic catalytic schemes., Shaw A, Bott R, Vonrhein C, Bricogne G, Power S, Day AG, J Mol Biol. 2002 Jul 5;320(2):303-9. PMID:12079387
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