1kh8
From Proteopedia
(New page: 200px<br /><applet load="1kh8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kh8, resolution 2.0Å" /> '''Structure of a cis-pr...) |
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| - | [[Image:1kh8.gif|left|200px]]<br /><applet load="1kh8" size=" | + | [[Image:1kh8.gif|left|200px]]<br /><applet load="1kh8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1kh8, resolution 2.0Å" /> | caption="1kh8, resolution 2.0Å" /> | ||
'''Structure of a cis-proline (P114) to glycine variant of Ribonuclease A'''<br /> | '''Structure of a cis-proline (P114) to glycine variant of Ribonuclease A'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Replacement of a cis-proline by glycine at position 114 in ribonuclease A | + | Replacement of a cis-proline by glycine at position 114 in ribonuclease A leads to a large decrease in thermal stability and simplifies the refolding kinetics. A crystallographic approach was used to determine whether the decrease in thermal stability results from the presence of a cis glycine peptide bond, or from a localized structural rearrangement caused by the isomerization of the mutated cis 114 peptide bond. The structure was solved at 2.0 A resolution and refined to an R-factor of 19.5% and an R(free) of 21.9%. The overall conformation of the protein was similar to that of wild-type ribonuclease A; however, there was a large localized rearrangement of the mutated loop (residues 110-117-a 9.3 A shift of the Calpha atom of residue 114). The peptide bond before Gly114 is in the trans configuration. Interestingly, a large anomalous difference density was found near residue 114, and was attributed to a bound cesium ion present in the crystallization experiment. The trans isomeric configuration of the peptide bond in the folded state of this mutant is consistent with the refolding kinetics previously reported, and the associated protein conformational change provides an explanation for the decreased thermal stability. |
==About this Structure== | ==About this Structure== | ||
| - | 1KH8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with SO4 and CS as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Pancreatic_ribonuclease Pancreatic ribonuclease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.27.5 3.1.27.5] Full crystallographic information is available from [http:// | + | 1KH8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=CS:'>CS</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Pancreatic_ribonuclease Pancreatic ribonuclease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.27.5 3.1.27.5] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KH8 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Pancreatic ribonuclease]] | [[Category: Pancreatic ribonuclease]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Fox, R | + | [[Category: Fox, R O.]] |
| - | [[Category: Friedman, A | + | [[Category: Friedman, A M.]] |
| - | [[Category: Schultz, D | + | [[Category: Schultz, D A.]] |
| - | [[Category: White, M | + | [[Category: White, M A.]] |
[[Category: CS]] | [[Category: CS]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
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[[Category: trans]] | [[Category: trans]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:34:07 2008'' |
Revision as of 11:34, 21 February 2008
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Structure of a cis-proline (P114) to glycine variant of Ribonuclease A
Overview
Replacement of a cis-proline by glycine at position 114 in ribonuclease A leads to a large decrease in thermal stability and simplifies the refolding kinetics. A crystallographic approach was used to determine whether the decrease in thermal stability results from the presence of a cis glycine peptide bond, or from a localized structural rearrangement caused by the isomerization of the mutated cis 114 peptide bond. The structure was solved at 2.0 A resolution and refined to an R-factor of 19.5% and an R(free) of 21.9%. The overall conformation of the protein was similar to that of wild-type ribonuclease A; however, there was a large localized rearrangement of the mutated loop (residues 110-117-a 9.3 A shift of the Calpha atom of residue 114). The peptide bond before Gly114 is in the trans configuration. Interestingly, a large anomalous difference density was found near residue 114, and was attributed to a bound cesium ion present in the crystallization experiment. The trans isomeric configuration of the peptide bond in the folded state of this mutant is consistent with the refolding kinetics previously reported, and the associated protein conformational change provides an explanation for the decreased thermal stability.
About this Structure
1KH8 is a Single protein structure of sequence from Bos taurus with and as ligands. Active as Pancreatic ribonuclease, with EC number 3.1.27.5 Full crystallographic information is available from OCA.
Reference
The crystal structure of the cis-proline to glycine variant (P114G) of ribonuclease A., Schultz DA, Friedman AM, White MA, Fox RO, Protein Sci. 2005 Nov;14(11):2862-70. Epub 2005 Sep 30. PMID:16199662
Page seeded by OCA on Thu Feb 21 13:34:07 2008
Categories: Bos taurus | Pancreatic ribonuclease | Single protein | Fox, R O. | Friedman, A M. | Schultz, D A. | White, M A. | CS | SO4 | Cesium | Cis | Proline | Ribonuclease a | Rnase a | Trans
