2blj: Difference between revisions
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==Overview== | ==Overview== | ||
We have determined eight X-ray structures of myoglobin mutant L29W at | We have determined eight X-ray structures of myoglobin mutant L29W at various experimental conditions. In addition, infrared spectroscopic experiments are presented, which are discussed in the light of the X-ray structures. Two distinct conformations of the CO-ligated protein were identified, giving rise to two stretching bands of heme-bound CO. If L29W MbCO crystals are illuminated around 180 K, a deoxy species is formed. The CO molecules migrate to the proximal side of the heme and remain trapped in the so-called Xe1 cavity upon temperature decrease to 105 K. The structure of this photoproduct is almost identical to the equilibrium high-temperature deoxy Mb structure. If the temperature is cycled to increasingly higher values, CO recombination is observed. Three intermediate structures have been determined during the rebinding process. Efficient recombination occurs only above 180 K, the characteristic temperature for the onset of protein dynamics. Rebinding is remarkably slow because bulky residues His64 and Trp29 block important migration pathways of the CO molecule. | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Physeter catodon]] | [[Category: Physeter catodon]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Nienhaus, G | [[Category: Nienhaus, G U.]] | ||
[[Category: Nienhaus, K.]] | [[Category: Nienhaus, K.]] | ||
[[Category: Ostermann, A.]] | [[Category: Ostermann, A.]] | ||
[[Category: Parak, F | [[Category: Parak, F G.]] | ||
[[Category: Schmidt, M.]] | [[Category: Schmidt, M.]] | ||
[[Category: CMO]] | [[Category: CMO]] | ||
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[[Category: oxygen transport]] | [[Category: oxygen transport]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:39:05 2008'' | ||
Revision as of 17:39, 21 February 2008
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STRUCTURE OF L29W MBCO
OverviewOverview
We have determined eight X-ray structures of myoglobin mutant L29W at various experimental conditions. In addition, infrared spectroscopic experiments are presented, which are discussed in the light of the X-ray structures. Two distinct conformations of the CO-ligated protein were identified, giving rise to two stretching bands of heme-bound CO. If L29W MbCO crystals are illuminated around 180 K, a deoxy species is formed. The CO molecules migrate to the proximal side of the heme and remain trapped in the so-called Xe1 cavity upon temperature decrease to 105 K. The structure of this photoproduct is almost identical to the equilibrium high-temperature deoxy Mb structure. If the temperature is cycled to increasingly higher values, CO recombination is observed. Three intermediate structures have been determined during the rebinding process. Efficient recombination occurs only above 180 K, the characteristic temperature for the onset of protein dynamics. Rebinding is remarkably slow because bulky residues His64 and Trp29 block important migration pathways of the CO molecule.
About this StructureAbout this Structure
2BLJ is a Single protein structure of sequence from Physeter catodon with and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
Ligand migration and protein fluctuations in myoglobin mutant L29W., Nienhaus K, Ostermann A, Nienhaus GU, Parak FG, Schmidt M, Biochemistry. 2005 Apr 5;44(13):5095-105. PMID:15794647
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