Abstract
A two-dimensional TROSY-based z-exchange 1H-15N correlation experiment for the quantitative analysis of kinetic processes in the slow exchange regime is presented. The pulse scheme converts the product operator terms Nz into 2NzHz and 2N zHz into -NZ in the middle of the z-mixing period, thereby suppressing the buildup of spurious semi-TROSY peaks arising from the different relaxation rates for the Nz and 2N zHz terms and simplifying the behavior of longitudinal magnetization for an exchanging system during the mixing period. Theoretical considerations and experimental data demonstrate that the TROSY-based z-exchange experiment permits quantitative determination of rate constants using the same procedure as that for the conventional non-TROSY 15N z-exchange experiment. Line narrowing as a consequence of the use of the TROSY principle makes the method particularly suitable for kinetic studies at low temperature, thereby permitting activation energies to be extracted from data acquired over a wider temperature range. We applied this method to the investigation of the process whereby the HoxD9 homeodomain translocates between specific target sites on different DNA molecules via a direct transfer mechanism without going through the intermediary of free protein. The activation enthalpy for intermolecular translocation was determined to be 17 kcal/mol.
Original language | English (US) |
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Pages (from-to) | 13232-13237 |
Number of pages | 6 |
Journal | Journal of the American Chemical Society |
Volume | 129 |
Issue number | 43 |
DOIs | |
State | Published - Oct 31 2007 |
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ASJC Scopus subject areas
- Chemistry(all)
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TROSY-based z-exchange spectroscopy : Application to the determination of the activation energy for intermolecular protein translocation between specific sites on different DNA molecules. / Sahu, Debashish; Clore, G. Marius; Iwahara, Junji.
In: Journal of the American Chemical Society, Vol. 129, No. 43, 31.10.2007, p. 13232-13237.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - TROSY-based z-exchange spectroscopy
T2 - Application to the determination of the activation energy for intermolecular protein translocation between specific sites on different DNA molecules
AU - Sahu, Debashish
AU - Clore, G. Marius
AU - Iwahara, Junji
PY - 2007/10/31
Y1 - 2007/10/31
N2 - A two-dimensional TROSY-based z-exchange 1H-15N correlation experiment for the quantitative analysis of kinetic processes in the slow exchange regime is presented. The pulse scheme converts the product operator terms Nz into 2NzHz and 2N zHz into -NZ in the middle of the z-mixing period, thereby suppressing the buildup of spurious semi-TROSY peaks arising from the different relaxation rates for the Nz and 2N zHz terms and simplifying the behavior of longitudinal magnetization for an exchanging system during the mixing period. Theoretical considerations and experimental data demonstrate that the TROSY-based z-exchange experiment permits quantitative determination of rate constants using the same procedure as that for the conventional non-TROSY 15N z-exchange experiment. Line narrowing as a consequence of the use of the TROSY principle makes the method particularly suitable for kinetic studies at low temperature, thereby permitting activation energies to be extracted from data acquired over a wider temperature range. We applied this method to the investigation of the process whereby the HoxD9 homeodomain translocates between specific target sites on different DNA molecules via a direct transfer mechanism without going through the intermediary of free protein. The activation enthalpy for intermolecular translocation was determined to be 17 kcal/mol.
AB - A two-dimensional TROSY-based z-exchange 1H-15N correlation experiment for the quantitative analysis of kinetic processes in the slow exchange regime is presented. The pulse scheme converts the product operator terms Nz into 2NzHz and 2N zHz into -NZ in the middle of the z-mixing period, thereby suppressing the buildup of spurious semi-TROSY peaks arising from the different relaxation rates for the Nz and 2N zHz terms and simplifying the behavior of longitudinal magnetization for an exchanging system during the mixing period. Theoretical considerations and experimental data demonstrate that the TROSY-based z-exchange experiment permits quantitative determination of rate constants using the same procedure as that for the conventional non-TROSY 15N z-exchange experiment. Line narrowing as a consequence of the use of the TROSY principle makes the method particularly suitable for kinetic studies at low temperature, thereby permitting activation energies to be extracted from data acquired over a wider temperature range. We applied this method to the investigation of the process whereby the HoxD9 homeodomain translocates between specific target sites on different DNA molecules via a direct transfer mechanism without going through the intermediary of free protein. The activation enthalpy for intermolecular translocation was determined to be 17 kcal/mol.
UR - http://www.scopus.com/inward/record.url?scp=35848970780&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=35848970780&partnerID=8YFLogxK
U2 - 10.1021/ja074604f
DO - 10.1021/ja074604f
M3 - Article
C2 - 17918842
AN - SCOPUS:35848970780
VL - 129
SP - 13232
EP - 13237
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 43
ER -