5azu
From Proteopedia
(New page: 200px<br /><applet load="5azu" size="450" color="white" frame="true" align="right" spinBox="true" caption="5azu, resolution 1.9Å" /> '''CRYSTAL STRUCTURE ANA...) |
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- | [[Image:5azu.gif|left|200px]]<br /><applet load="5azu" size=" | + | [[Image:5azu.gif|left|200px]]<br /><applet load="5azu" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="5azu, resolution 1.9Å" /> | caption="5azu, resolution 1.9Å" /> | ||
'''CRYSTAL STRUCTURE ANALYSIS OF OXIDIZED PSEUDOMONAS AERUGINOSA AZURIN AT PH 5.5 AND PH 9.0. A PH-INDUCED CONFORMATIONAL TRANSITION INVOLVES A PEPTIDE BOND FLIP'''<br /> | '''CRYSTAL STRUCTURE ANALYSIS OF OXIDIZED PSEUDOMONAS AERUGINOSA AZURIN AT PH 5.5 AND PH 9.0. A PH-INDUCED CONFORMATIONAL TRANSITION INVOLVES A PEPTIDE BOND FLIP'''<br /> | ||
==Overview== | ==Overview== | ||
- | The X-ray crystal structure of recombinant wild-type azurin from | + | The X-ray crystal structure of recombinant wild-type azurin from Pseudomonas aeruginosa was determined by difference Fourier techniques using phases derived from the structure of the mutant His35Leu. Two data sets were collected from a single crystal of oxidized azurin soaked in mother liquor buffered at pH 5.5 and pH 9.0, respectively. Both data sets extend to 1.93 A resolution. The two pH forms were refined independently to crystallographic R-factors of 17.6% (pH 5.5) and 17.5% (pH 9.0). The conformational transition previously attributed to the protonation/deprotonation of residue His35 (pKa(red) = 7.3, pKa(ox) = 6.2), which lies in a crevice of the protein close to the copper binding site, involves a concomitant Pro36-Gly37 main-chain peptide bond flip. At the lower pH, the protonated imidazole N delta 1 of His35 forms a strong hydrogen bond with the carbonyl oxygen from Pro36, while at alkaline pH the deprotonated N delta 1 acts as an acceptor of a weak hydrogen bond from HN Gly37. The structure of the remainder of the azurin molecule, including the copper binding site, is not significantly affected by this transition. |
==About this Structure== | ==About this Structure== | ||
- | 5AZU is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with CU and NO3 as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 5AZU is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with <scene name='pdbligand=CU:'>CU</scene> and <scene name='pdbligand=NO3:'>NO3</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5AZU OCA]. |
==Reference== | ==Reference== | ||
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[[Category: electron transport(copper binding)]] | [[Category: electron transport(copper binding)]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:14:48 2008'' |
Revision as of 17:14, 21 February 2008
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CRYSTAL STRUCTURE ANALYSIS OF OXIDIZED PSEUDOMONAS AERUGINOSA AZURIN AT PH 5.5 AND PH 9.0. A PH-INDUCED CONFORMATIONAL TRANSITION INVOLVES A PEPTIDE BOND FLIP
Overview
The X-ray crystal structure of recombinant wild-type azurin from Pseudomonas aeruginosa was determined by difference Fourier techniques using phases derived from the structure of the mutant His35Leu. Two data sets were collected from a single crystal of oxidized azurin soaked in mother liquor buffered at pH 5.5 and pH 9.0, respectively. Both data sets extend to 1.93 A resolution. The two pH forms were refined independently to crystallographic R-factors of 17.6% (pH 5.5) and 17.5% (pH 9.0). The conformational transition previously attributed to the protonation/deprotonation of residue His35 (pKa(red) = 7.3, pKa(ox) = 6.2), which lies in a crevice of the protein close to the copper binding site, involves a concomitant Pro36-Gly37 main-chain peptide bond flip. At the lower pH, the protonated imidazole N delta 1 of His35 forms a strong hydrogen bond with the carbonyl oxygen from Pro36, while at alkaline pH the deprotonated N delta 1 acts as an acceptor of a weak hydrogen bond from HN Gly37. The structure of the remainder of the azurin molecule, including the copper binding site, is not significantly affected by this transition.
About this Structure
5AZU is a Single protein structure of sequence from Pseudomonas aeruginosa with and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure analysis of oxidized Pseudomonas aeruginosa azurin at pH 5.5 and pH 9.0. A pH-induced conformational transition involves a peptide bond flip., Nar H, Messerschmidt A, Huber R, van de Kamp M, Canters GW, J Mol Biol. 1991 Oct 5;221(3):765-72. PMID:1942029
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