Measuring (1)H (N) temperature coefficients in invisible protein states by relaxation dispersion NMR spectroscopy.
J Biomol NMR. 2011 Mar 18;
Authors: Bouvignies G, Vallurupalli P, Cordes MH, Hansen DF, Kay LE
A method based on the Carr-Purcell-Meiboom-Gill relaxation dispersion experiment is presented for measuring the temperature coefficients of amide proton chemical shifts of low populated 'invisible' protein states that exchange with a 'visible' ground state on the millisecond time-scale. The utility of the approach is demonstrated with an application to an I58D mutant of the Pfl6 Cro protein that undergoes exchange between the native, folded state and a cold denatured, unfolded conformational ensemble that is populated at a level of 6% at 2.5°C. A wide distribution of amide temperature coefficients is measured for the unfolded state. The distribution is centered about -5.6*ppb/K, consistent with an absence of intra-molecular hydrogen bonds, on average. However, the large range of values (standard deviation of 2.1*ppb/K) strongly supports the notion that the unfolded state of the protein is not a true random coil polypeptide chain.
PMID: 21424227 [PubMed - as supplied by publisher]
Amide temperature coefficients in the protein G B1 domain
Amide temperature coefficients in the protein G B1 domain
Abstract Temperature coefficients have been measured for backbone amide 1H and 15N nuclei in the B1 domain of protein G (GB1), using temperatures in the range 283â??313 K, and pH values from 2.0 to 9.0. Many nuclei display pH-dependent coefficients, which were fitted to one or two pKa values. 1H coefficients showed the expected behaviour, in that hydrogen-bonded amides have less negative values, but for those amides involved in strong hydrogen bonds in regular secondary structure there is a negative correlation between strength...
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11-14-2011 08:45 AM
Quantifying millisecond time-scale exchange in proteins by CPMG relaxation dispersion NMR spectroscopy of side-chain carbonyl groups
Quantifying millisecond time-scale exchange in proteins by CPMG relaxation dispersion NMR spectroscopy of side-chain carbonyl groups
Abstract A new pulse sequence is presented for the measurement of relaxation dispersion profiles quantifying millisecond time-scale exchange dynamics of side-chain carbonyl groups in uniformly 13C labeled proteins. The methodology has been tested using the 87-residue colicin E7 immunity protein, Im7, which is known to fold via a partially structured low populated intermediate that interconverts with the folded, ground state on the millisecond time-scale....
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06-20-2011 03:31 PM
Quantifying millisecond time-scale exchange in proteins by CPMG relaxation dispersion NMR spectroscopy of side-chain carbonyl groups.
Quantifying millisecond time-scale exchange in proteins by CPMG relaxation dispersion NMR spectroscopy of side-chain carbonyl groups.
Quantifying millisecond time-scale exchange in proteins by CPMG relaxation dispersion NMR spectroscopy of side-chain carbonyl groups.
J Biomol NMR. 2011 Jun 18;
Authors: Hansen AL, Kay LE
A new pulse sequence is presented for the measurement of relaxation dispersion profiles quantifying millisecond time-scale exchange dynamics of side-chain carbonyl groups in uniformly (13)C labeled proteins. The methodology has...
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06-18-2011 01:10 PM
Measuring 1HN temperature coefficients in invisible protein states by relaxation dispersion NMR spectroscopy
Measuring 1HN temperature coefficients in invisible protein states by relaxation dispersion NMR spectroscopy
Abstract A method based on the Carr-Purcell-Meiboom-Gill relaxation dispersion experiment is presented for measuring the temperature coefficients of amide proton chemical shifts of low populated â??invisibleâ?? protein states that exchange with a â??visibleâ?? ground state on the millisecond time-scale. The utility of the approach is demonstrated with an application to an I58D mutant of the Pfl6 Cro protein that undergoes exchange between the native, folded state and a cold...
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03-22-2011 07:32 PM
[NMR paper] NMR spectroscopic characterization of millisecond protein folding by transverse relaxation dispersion measurements.
NMR spectroscopic characterization of millisecond protein folding by transverse relaxation dispersion measurements.
Related Articles NMR spectroscopic characterization of millisecond protein folding by transverse relaxation dispersion measurements.
J Am Chem Soc. 2005 Sep 28;127(38):13207-12
Authors: Zeeb M, Balbach J
The cold shock protein CspB adopts its native and functional tertiary structure on the millisecond time scale. We employed transverse relaxation NMR methods, which allow a quantitative measurement of the cooperativity of this...
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12-01-2010 06:56 PM
[NMR paper] Reconstructing NMR spectra of "invisible" excited protein states using HSQC and HMQC
Reconstructing NMR spectra of "invisible" excited protein states using HSQC and HMQC experiments.
Related Articles Reconstructing NMR spectra of "invisible" excited protein states using HSQC and HMQC experiments.
J Am Chem Soc. 2002 Oct 16;124(41):12352-60
Authors: Skrynnikov NR, Dahlquist FW, Kay LE
Carr-Purcell-Meiboom-Gill (CPMG) relaxation measurements employing trains of 180 degrees pulses with variable pulse spacing provide valuable information about systems undergoing millisecond-time-scale chemical exchange. Fits of the CPMG relaxation...
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11-24-2010 08:58 PM
Measurement of carbonyl chemical shifts of excited protein states by relaxation dispersion NMR spectroscopy: comparison between uniformly and selectively 13C labeled samples
Measurement of carbonyl chemical shifts of excited protein states by relaxation dispersion NMR spectroscopy: comparison between uniformly and selectively 13C labeled samples
Patrik Lundström, D. Flemming Hansen and Lewis E. Kay
Journal of Biomolecular NMR; 2008; 42(1); pp 35 - 47
Abstract: Carr–Purcell–Meiboom–Gill (CPMG) relaxation dispersion nuclear magnetic resonance (NMR) spectroscopy has emerged as a powerful method for quantifying chemical shifts of excited protein states. For many applications of the technique that involve the measurement of relaxation rates of carbon...
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09-21-2008 11:36 PM
Using relaxation dispersion NMR spectroscopy to determine structures of excited, invisible protein states
Using relaxation dispersion NMR spectroscopy to determine structures of excited, invisible protein states
D. Flemming Hansen, Pramodh Vallurupalli and Lewis E. Kay
Journal of Biomolecular NMR; 2008; 41(3); pp 113 - 120
Abstract:
Currently the main focus of structural biology is the determination of static three-dimensional representations of biomolecules that for the most part correspond to low energy (ground state) conformations. However, it is becoming increasingly well recognized that higher energy structures often play important roles in function as well. Because these conformers...