Dynamics of structure and energy of horse carboxymyoglobin after photodissociation of carbon monoxide.
Abstract: The energetics and structural volume changes after photodissociation of carboxymyoglobin are quantitatively investigated by laser-induced transient grating (TG) and photoacoustic calorimetric techniques. Various origins of the TG signal are distinguished: the phase grating signals due to temperature change, due to absorption spectrum change, and due to volume change. We found a new kinetics of approximately 700 ns (at room temperature), which was not observed by the flash photolysis technique. This kinetics should be attributed to the intermediate between the geminate pair and the fully dissociated state. The enthalpy of an intermediate species is determined to be 61 +/- 10 kJ/mol, which is smaller than the expected Fe-CO bond energy. The volume of MbCO slightly contracts (5 +/- 3 cm(3)/mol) during this process. CO is fully released from the protein by an exponential kinetics from 25 to -2 degrees C. During this escaping process, the volume expands by 14.7 +/- 2 cm(3)/mol at room temperature and 14 +/- 10 kJ/mol is released, which should represent the protein relaxation and the solvation of the CO (the enthalpy of this final state is 47 +/- 10 kJ/mol). A potential barrier between the intermediate and the fully dissociated state is DeltaH(*) = 41.3 kJ/mol and DeltaS(*) = 13.6 J mol(-1) K(-1). The TG experiment under a high wavenumber reveals that the volume expansion depends on the temperature from 25 to -2 degrees C. The volume changes and the energies of the intermediate species are discussed.
Publication Date: 2001-07-18 PubMed ID: 11457195DOI: 10.1021/ja9944655Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The study explores the changes in structure and energy of horse carboxymyoglobin following the photodissociation of carbon monoxide. The researchers used various techniques to study the energetic and volume alterations following this process, and uncovered new kinetic information not previously observed.
Research Methodology
- The researchers used laser-induced transient grating (TG) and photoacoustic calorimetric techniques to investigate the energetic and structural volume changes post carboxymyoglobin photodissociation.
- The analysis helped distinguish between phase grating signals attributable to temperature changes, absorption spectrum changes, and volume changes.
Key Findings
- The researchers identified new kinetics of about 700 ns at room temperature, not previously observed by conventional flash photolysis techniques. This evidence suggests the existence of an intermediate between the geminate pair (molecular entities formed together) and the complete dissociation state.
- The study estimates the enthalpy of the intermediate species to be 61 +/- 10 kJ/mol, a significantly smaller value than the expected iron-carbon monoxide bond energy.
- During this process, the volume of myoglobin-carbon monoxide compound (MbCO) slightly contracts (5 +/- 3 cm(3)/mol).
- Carbon monoxide (CO) is entirely released from the protein through an exponential kinetics from 25 to -2 degrees Celsius. There is a corresponding volume expansion by 14.7 +/- 2 cm(3)/mol, and the release of 14 +/- 10 kJ/mol of energy, believed to represent protein relaxation and CO solvation (interaction of CO with its surrounding environment).
- The final state enthalpy is calculated to be 47 +/- 10 kJ/mol.
- The study found potential barriers between the identified intermediate and the fully dissociated state, indexed with DeltaH(*) = 41.3 kJ/mol and DeltaS(*) = 13.6 J mol(-1) K(-1).
- High wavenumber TG experiments showed that volume expansion rates fluctuate with temperature from 25 to -2 degrees Celsius.
- The discussion also focuses on changes in volume and energy levels of the intermediate species.
Cite This Article
APA
Sakakura M, Yamaguchi S, Hirota N, Terazima M.
(2001).
Dynamics of structure and energy of horse carboxymyoglobin after photodissociation of carbon monoxide.
J Am Chem Soc, 123(18), 4286-4294.
https://doi.org/10.1021/ja9944655 Publication
Researcher Affiliations
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606, Japan.
MeSH Terms
- Algorithms
- Animals
- Carbon Monoxide / chemistry
- Chemical Phenomena
- Chemistry, Physical
- Horses
- Indicators and Reagents
- Kinetics
- Lasers
- Myoglobin / chemistry
- Photolysis
- Rosaniline Dyes
- Temperature
Citations
This article has been cited 11 times.- Nakasone Y, Terazima M. A Time-Resolved Diffusion Technique for Detection of the Conformational Changes and Molecular Assembly/Disassembly Processes of Biomolecules.. Front Genet 2021;12:691010.
- Nagao S, Ishikawa H, Yamada T, Mizutani Y, Hirota S. Carbon monoxide binding properties of domain-swapped dimeric myoglobin.. J Biol Inorg Chem 2015 Apr;20(3):523-30.
- Marcelli A, Abbruzzetti S, Bustamante JP, Feis A, Bonamore A, Boffi A, Gellini C, Salvi PR, Estrin DA, Bruno S, Viappiani C, Foggi P. Following ligand migration pathways from picoseconds to milliseconds in type II truncated hemoglobin from Thermobifida fusca.. PLoS One 2012;7(7):e39884.
- Kim KH, Muniyappan S, Oang KY, Kim JG, Nozawa S, Sato T, Koshihara SY, Henning R, Kosheleva I, Ki H, Kim Y, Kim TW, Kim J, Adachi S, Ihee H. Direct observation of cooperative protein structural dynamics of homodimeric hemoglobin from 100 ps to 10 ms with pump-probe X-ray solution scattering.. J Am Chem Soc 2012 Apr 25;134(16):7001-8.
- Kim KH, Oang KY, Kim J, Lee JH, Kim Y, Ihee H. Direct observation of myoglobin structural dynamics from 100 picoseconds to 1 microsecond with picosecond X-ray solution scattering.. Chem Commun (Camb) 2011 Jan 7;47(1):289-91.
- Nishihara Y, Kato S, Hayashi S. Protein collective motions coupled to ligand migration in myoglobin.. Biophys J 2010 Apr 21;98(8):1649-57.
- Cho HS, Dashdorj N, Schotte F, Graber T, Henning R, Anfinrud P. Protein structural dynamics in solution unveiled via 100-ps time-resolved x-ray scattering.. Proc Natl Acad Sci U S A 2010 Apr 20;107(16):7281-6.
- Kumar R, Bhuyan AK. Entropic stabilization of myoglobin by subdenaturing concentrations of guanidine hydrochloride.. J Biol Inorg Chem 2009 Jan;14(1):11-21.
- Ohmori H, Nagy L, Dorogi M, Terazima M. Charge stabilization in reaction center protein investigated by optical heterodyne detected transient grating spectroscopy.. Eur Biophys J 2008 Sep;37(7):1167-74.
- Inoue K, Sasaki J, Morisaki M, Tokunaga F, Terazima M. Time-resolved detection of sensory rhodopsin II-transducer interaction.. Biophys J 2004 Oct;87(4):2587-97.
- Miksovská J, Day JH, Larsen RW. Volume and enthalpy profiles of CO rebinding to horse heart myoglobin.. J Biol Inorg Chem 2003 Jul;8(6):621-5.
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