NMR Studies of Biophysical Problems

Abstract

Nuclear magnetic resonance (NMR) has become more and more actively used in various biophysical and biochemical studies. Under such circumstances it seems timely to publish a special number of this Journal containing papers which introduce recent attainments in this field to non-specialist readers.The importance of NMR in the studies of biological molecules and higher-order systems stems from the following features. (1) Thanks to the developments of high-field NMR spectrometers with superconducting magnets, it is now possible to perform detailed investigations of the microstructure of biopolymers. (2) Possibilities of gaining a deeper insight into molecular motions are opened by the advent of pulse. Fourier transform techniques through accurate measurements of the spin-lattice relaxation times. (3) New aspects of biomolecular structures are being revealed by the application of recent experimental methods such as the use of paramagnetic probes. (4) The observation of resonances of various nuclei other than 1H (e. g., 13C, 15N, 31P, 19F, and 2H) provides a powerful tool for solving many problems which have not been so far tractable.In Japan also, NMR studies of biological systems are steadily increasing in number and advancing in quality. We find that quite a high percentage of the papers reported at the domestic meetings and conferences during 1974-1975 are concerned with either measurements of the spin-lattice relaxation times or the use of paramagnetic probes. Therefore, The papers published in this special number are also more or less related to these topics. The title and author (s) of each paper are as follows.1. Introduction (M. Tasumi & T. Iizuka)2. Molecular motions and spectral assignments based on the NMR relaxation mea- surements (R. Chujõ)3. Use of nuclear magnetic relaxation times to the determination of molecular conformation in solution (K. Akasaka & S. Shibata)4. Side-chain conformation of polyamino acids (K. Nagayama)5. NMR studies on the phospholipids from an unsaturated fatty-acid auxotroph of E. Coli (H. Akutsu & Y. Kyogoku)6. Structural studies on membrane models by NMR spectroscopy (M. Kainosho)7. Studies on the structure and function of hemoproteins and heme-enzymes by FT-NMR with superconducting magnet (I. Morishima, T. Inubushi & T. Iizuka)8. Structural studies of biomolecules by the lanthanide-ion probe method (M. Tasumi & F. Inagaki)