Temperature-jump NMR study of protein folding: Ribonuclease A at low pH
- 1 May 1991
- journal article
- Published by Springer Science and Business Media LLC in Journal of Biomolecular NMR
- Vol. 1 (1), 65-70
- https://doi.org/10.1007/bf01874569
Abstract
The kinetic process of folding of bovine pancreatic ribonuclease A in a2H2O environment at pH 1.2 was examined by a recently developed temperature-jump NMR method (Akasaka et al., (1990) Rev. Sci. Instrum.61, 66–68). Upon temperature-jump down from 45°C to 29°C, which was attained within 6 s, the proton NMR spectral changes were followed consecutively in time intervals of seconds. There was a rapid spectral change, which was finished within the jump period, followed by a much slower process which lasted for a minute or longer. Rates of the slower process were measured at different positions of the polypeptide chain as intensity changes of individual His and Tyr proton signals of the folded conformer and as intensity changes of aliphatic and His protons of the unfolded conformer. Most of these rates coincided with each other within experimental error with an average value of 2.8×10−2s−1. The result gave clear experimental evidence that the slow folding of RNase A at low pH is a cooperative process involving most regions of the molecule, not only thermodynamically, but kinetically as well.Keywords
This publication has 7 references indexed in Scilit:
- Construction and performance of a temperature-jump NMR apparatusReview of Scientific Instruments, 1990
- Structural studies of a folding intermediate of bovine pancreatic ribonuclease A by continuous recycled flowBiochemistry, 1988
- 1H Nuclear Magnetic Resonance Titration Curves and Microenvironments of Aromatic Residues in Bovine Pancreatic Ribonuclease AThe Journal of Biochemistry, 1983
- Specific Intermediates in the Folding Reactions of Small Proteins and the Mechanism of Protein FoldingAnnual Review of Biochemistry, 1982
- The Aromatic Residues of Bovine Pancreatic Ribonuclease Studied by 1H Nuclear Magnetic ResonanceEuropean Journal of Biochemistry, 1979
- Nuclear magnetic resonance evidence for a structural intermediate at an early stage in the refolding of ribonuclease AJournal of Molecular Biology, 1978
- A quantitative treatment of the kinetics of the folding transition of ribonuclease ABiochemistry, 1976