Use of 31P and 13C NMR to study enzyme mechanisms.

A number of complex biochemical problems have been solved recently by application of new techniques in which 31P and 13C NMR spectroscopy is used. Oxygen isotope exchange phenomena were studied by these NMR methods and used to analyze individual mechanistic events in enzymatic reactions. The existence of intermediates in the reactions catalyzed by glutamine synthetase (EC 6.3.1.2) and carbamyl-phosphate synthetase (EC 2.7.2.9) has been established as well as the kinetic competence of these intermediates for each enzyme. The NMR theory and kinetic experiments required to conduct such studies are discussed.