31P nuclear magnetic resonance studies of crayfish (Orconectes virilis). The use of inversion spin transfer to monitor enzyme kinetics in vivo

Abstract

31P NMR was used to observe in vivo the steady-state levels of phosphorus-containing metabolites in the crayfish Orconectes virilis, and the intracellular pH of the abdominal muscle was determined. Measurement of spin-lattice relaxation times and spin transfer experiments enabled calculation of unidirectional rate constants and activation energies for the arginine kinase reaction in vivo.