2fu7: Difference between revisions

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New page: left|200px<br /><applet load="2fu7" size="450" color="white" frame="true" align="right" spinBox="true" caption="2fu7, resolution 1.85Å" /> '''Zinc-beta-lactamase ...
 
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[[Image:2fu7.jpg|left|200px]]<br /><applet load="2fu7" size="450" color="white" frame="true" align="right" spinBox="true"  
[[Image:2fu7.jpg|left|200px]]<br /><applet load="2fu7" size="350" color="white" frame="true" align="right" spinBox="true"  
caption="2fu7, resolution 1.85&Aring;" />
caption="2fu7, resolution 1.85&Aring;" />
'''Zinc-beta-lactamase L1 from stenotrophomonas maltophilia (Cu-substituted form)'''<br />
'''Zinc-beta-lactamase L1 from stenotrophomonas maltophilia (Cu-substituted form)'''<br />


==Overview==
==Overview==
The 3-D structure of Bacillus cereus (569/H/9) beta-lactamase (EC, 3.5.2.6), which catalyses the hydrolysis of nearly all beta-lactams, has, been solved at 2.5 A resolution by the multiple isomorphous replacement, method, with density modification and phase combination, from crystals of, the native protein and of a specially designed mutant (T97C). The current, model includes 212 of the 227 amino acid residues, the zinc ion and 10, water molecules. The protein is folded into a beta beta sandwich with, helices on each external face. To our knowledge, this fold has never been, observed. An approximate internal molecular symmetry is found, with a, 2-fold axis passing roughly through the zinc ion and suggesting a possible, gene duplication. The active site is located at one edge of the beta beta, sandwich and near the N-terminal end of a helix. The zinc ion is, coordinated by three histidine residues (86, 88 and 149) and a water, molecule. A sequence comparison of the relevant metallo-beta-lactamases, based on this protein structure, highlights a few well-conserved amino, acid residues. The structure shows that most of these residues are in the, active site. Among these, aspartic acid 90 and histidine 210 participate, in a proposed catalytic mechanism for beta-lactam hydrolysis.
The 3-D structure of Bacillus cereus (569/H/9) beta-lactamase (EC 3.5.2.6), which catalyses the hydrolysis of nearly all beta-lactams, has been solved at 2.5 A resolution by the multiple isomorphous replacement method, with density modification and phase combination, from crystals of the native protein and of a specially designed mutant (T97C). The current model includes 212 of the 227 amino acid residues, the zinc ion and 10 water molecules. The protein is folded into a beta beta sandwich with helices on each external face. To our knowledge, this fold has never been observed. An approximate internal molecular symmetry is found, with a 2-fold axis passing roughly through the zinc ion and suggesting a possible gene duplication. The active site is located at one edge of the beta beta sandwich and near the N-terminal end of a helix. The zinc ion is coordinated by three histidine residues (86, 88 and 149) and a water molecule. A sequence comparison of the relevant metallo-beta-lactamases, based on this protein structure, highlights a few well-conserved amino acid residues. The structure shows that most of these residues are in the active site. Among these, aspartic acid 90 and histidine 210 participate in a proposed catalytic mechanism for beta-lactam hydrolysis.


==About this Structure==
==About this Structure==
2FU7 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Stenotrophomonas_maltophilia Stenotrophomonas maltophilia] with CU, SO4, PHN and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2FU7 OCA].  
2FU7 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Stenotrophomonas_maltophilia Stenotrophomonas maltophilia] with <scene name='pdbligand=CU:'>CU</scene>, <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=PHN:'>PHN</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FU7 OCA].  


==Reference==
==Reference==
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[[Category: zn]]
[[Category: zn]]


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