1j7z: Difference between revisions
New page: left|200px<br /><applet load="1j7z" size="450" color="white" frame="true" align="right" spinBox="true" caption="1j7z, resolution 2.25Å" /> '''Osmolyte Stabilizati... |
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[[Image:1j7z.gif|left|200px]]<br /><applet load="1j7z" size=" | [[Image:1j7z.gif|left|200px]]<br /><applet load="1j7z" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1j7z, resolution 2.25Å" /> | caption="1j7z, resolution 2.25Å" /> | ||
'''Osmolyte Stabilization of Ribonuclease'''<br /> | '''Osmolyte Stabilization of Ribonuclease'''<br /> | ||
==Overview== | ==Overview== | ||
Osmolytes stabilize proteins to thermal and chemical denaturation. We have | Osmolytes stabilize proteins to thermal and chemical denaturation. We have studied the effects of the osmolytes sarcosine, betaine, trimethylamine-N-oxide, and taurine on the structure and stability of the protein.peptide complex RNase S using x-ray crystallography and titration calorimetry, respectively. The largest degree of stabilization is achieved with 6 m sarcosine, which increases the denaturation temperatures of RNase S and S pro by 24.6 and 17.4 degrees C, respectively, at pH 5 and protects both proteins against tryptic cleavage. Four crystal structures of RNase S in the presence of different osmolytes do not offer any evidence for osmolyte binding to the folded state of the protein or any perturbation in the water structure surrounding the protein. The degree of stabilization in 6 m sarcosine increases with temperature, ranging from -0.52 kcal mol(-1) at 20 degrees C to -5.4 kcal mol(-1) at 60 degrees C. The data support the thesis that osmolytes that stabilize proteins, do so by perturbing unfolded states, which change conformation to a compact, folding competent state in the presence of osmolyte. The increased stabilization thus results from a decrease in conformational entropy of the unfolded state. | ||
==About this Structure== | ==About this Structure== | ||
1J7Z is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with SO4 and NH2 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:// | 1J7Z is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=NH2:'>NH2</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=1J7Z OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Pancreatic ribonuclease]] | [[Category: Pancreatic ribonuclease]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Ratnaparkhi, G | [[Category: Ratnaparkhi, G S.]] | ||
[[Category: Varadarajan, R.]] | [[Category: Varadarajan, R.]] | ||
[[Category: NH2]] | [[Category: NH2]] | ||
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[[Category: trimethylamine-n-oxide]] | [[Category: trimethylamine-n-oxide]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:19:42 2008'' | ||
Revision as of 14:19, 21 February 2008
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Osmolyte Stabilization of Ribonuclease
OverviewOverview
Osmolytes stabilize proteins to thermal and chemical denaturation. We have studied the effects of the osmolytes sarcosine, betaine, trimethylamine-N-oxide, and taurine on the structure and stability of the protein.peptide complex RNase S using x-ray crystallography and titration calorimetry, respectively. The largest degree of stabilization is achieved with 6 m sarcosine, which increases the denaturation temperatures of RNase S and S pro by 24.6 and 17.4 degrees C, respectively, at pH 5 and protects both proteins against tryptic cleavage. Four crystal structures of RNase S in the presence of different osmolytes do not offer any evidence for osmolyte binding to the folded state of the protein or any perturbation in the water structure surrounding the protein. The degree of stabilization in 6 m sarcosine increases with temperature, ranging from -0.52 kcal mol(-1) at 20 degrees C to -5.4 kcal mol(-1) at 60 degrees C. The data support the thesis that osmolytes that stabilize proteins, do so by perturbing unfolded states, which change conformation to a compact, folding competent state in the presence of osmolyte. The increased stabilization thus results from a decrease in conformational entropy of the unfolded state.
About this StructureAbout this Structure
1J7Z is a Protein complex structure of sequences 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.
ReferenceReference
Osmolytes stabilize ribonuclease S by stabilizing its fragments S protein and S peptide to compact folding-competent states., Ratnaparkhi GS, Varadarajan R, J Biol Chem. 2001 Aug 3;276(31):28789-98. Epub 2001 May 23. PMID:11373282
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