1mqv
From Proteopedia
(New page: 200px<br /><applet load="1mqv" size="450" color="white" frame="true" align="right" spinBox="true" caption="1mqv, resolution 1.78Å" /> '''Crystal Structure of...) |
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| - | [[Image:1mqv.gif|left|200px]]<br /><applet load="1mqv" size=" | + | [[Image:1mqv.gif|left|200px]]<br /><applet load="1mqv" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1mqv, resolution 1.78Å" /> | caption="1mqv, resolution 1.78Å" /> | ||
'''Crystal Structure of the Q1A/F32W/W72F mutant of Rhodopseudomonas palustris cytochrome c' (prime) expressed in E. coli'''<br /> | '''Crystal Structure of the Q1A/F32W/W72F mutant of Rhodopseudomonas palustris cytochrome c' (prime) expressed in E. coli'''<br /> | ||
==Overview== | ==Overview== | ||
| - | We employed fluorescence energy-transfer probes to investigate the | + | We employed fluorescence energy-transfer probes to investigate the polypeptide dynamics accompanying cytochrome c' folding. Analysis of fluorescence energy-transfer kinetics from wild-type Trp-72 or Trp-32 in a crystallographically characterized (1.78 A) Q1A/F32W/W72F mutant shows that there is structural heterogeneity in denatured cytochrome c'. Even at guanidine hydrochloride concentrations well beyond the unfolding transition, a substantial fraction of the polypeptides ( approximately 50%) adopts compact conformations (tryptophan-to-heme distance, approximately 25 A) in both pseudo-wild-type (Q1A) and mutant proteins. A burst phase (< or =5 ms) is revealed when stopped flow-triggered refolding is probed by tryptophan intensity: measurements on the Q1A protein show that approximately 75% of the Trp-72 fluorescence (83% for Trp-32) is quenched within the mixing deadtime, suggesting that most of the polypeptides have collapsed. |
==About this Structure== | ==About this Structure== | ||
| - | 1MQV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rhodopseudomonas_palustris Rhodopseudomonas palustris] with HEM as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1MQV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rhodopseudomonas_palustris Rhodopseudomonas palustris] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MQV OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Rhodopseudomonas palustris]] | [[Category: Rhodopseudomonas palustris]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Engman, K | + | [[Category: Engman, K C.]] |
| - | [[Category: Gray, H | + | [[Category: Gray, H B.]] |
| - | [[Category: Lee, J | + | [[Category: Lee, J C.]] |
| - | [[Category: Tezcan, F | + | [[Category: Tezcan, F A.]] |
| - | [[Category: Winkler, J | + | [[Category: Winkler, J R.]] |
[[Category: HEM]] | [[Category: HEM]] | ||
[[Category: four-helix bundle]] | [[Category: four-helix bundle]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:58:06 2008'' |
Revision as of 11:58, 21 February 2008
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Crystal Structure of the Q1A/F32W/W72F mutant of Rhodopseudomonas palustris cytochrome c' (prime) expressed in E. coli
Overview
We employed fluorescence energy-transfer probes to investigate the polypeptide dynamics accompanying cytochrome c' folding. Analysis of fluorescence energy-transfer kinetics from wild-type Trp-72 or Trp-32 in a crystallographically characterized (1.78 A) Q1A/F32W/W72F mutant shows that there is structural heterogeneity in denatured cytochrome c'. Even at guanidine hydrochloride concentrations well beyond the unfolding transition, a substantial fraction of the polypeptides ( approximately 50%) adopts compact conformations (tryptophan-to-heme distance, approximately 25 A) in both pseudo-wild-type (Q1A) and mutant proteins. A burst phase (< or =5 ms) is revealed when stopped flow-triggered refolding is probed by tryptophan intensity: measurements on the Q1A protein show that approximately 75% of the Trp-72 fluorescence (83% for Trp-32) is quenched within the mixing deadtime, suggesting that most of the polypeptides have collapsed.
About this Structure
1MQV is a Single protein structure of sequence from Rhodopseudomonas palustris with as ligand. Full crystallographic information is available from OCA.
Reference
Structural features of cytochrome c' folding intermediates revealed by fluorescence energy-transfer kinetics., Lee JC, Engman KC, Tezcan FA, Gray HB, Winkler JR, Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):14778-82. Epub 2002 Oct 29. PMID:12407175
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