Nuclear magnetic resonance in biochemistry

Abstract

Novel applications of nuclear magnetic resonance (NMR) spectroscopy in biochemistry are reviewed. The biological functions of peptides are correlated with the conformations of membrane-bound molecules rather than the conformations in aqueous solutions. The membrane-bound conformations may be elucidated by the analysis of transferred nuclear Overhauser effects. The conformations of nucleotide inhibitors as bound to ribonucleases may be analysed by nuclear Overhauser effects. Thus, ribonuclease T1 is found to have binding sites for guanine base and 3'-phosphate but not for 5'-phosphate group. From the 13C-NMR spectra of subtilisin inhibitors as labeled with [1-13C]Met and [15N]-Val, the inhibitor is found to form a Michaelis complex with subtilisin. From the proton NMR analyses of immunoglobin (IgG), the hinge region (indispensable for the activation of complement system) is found to be the most mobile. The uridine residue in the first position of anticodon of transfer ribonucleic acids (tRNA) is always modified after transcription. The conformational characteristics of the modified uridines have been elucidated by proton NMR analyses. The modifications of uridine in the first position of anticodon are now found to contribute to correct and efficient translations of codons, through the regulation of rigidity/flexibility of the anticodon moiety of tRNA.