P-31-NMR AND H-1-NMR SPECTRA OF MANDUCA-SEXTA LARVAE PARASITIZED BY STEINERNEMA-CARPOCAPSAE

In vivo P-31-nuclear magnetic resonance (NMR) spectroscopy was used to study changes in phosphorus metabolites of the fifth instar Manduca s exta larva parasitized by Steinernema carpocapsae. The P-31-NMR spectr um of the intact larva was shown to be composed of five signals attrib utable to such phosphometabolites as the alpha, beta and gamma phospha tes of adenosine triphosphate at -10.3, -19.05, and -5.2 ppm, respecti vely; phosphate of phospho-arginine at -3.26 ppm; and the largest sign al at 3.45 ppm including phosphates of inorganic phosphate (Pi) and ph osphomonoesters: fructose-6-phosphate, trehalose-6-phosphate, alpha-gl ycerophosphate (alpha-GP) and phosphorylcholine. Infection with S. car pocapsae had significant effects on the P-31-NMR and H-1-NMR spectra o f the intact larva: an increase in the level of P-31 Signal of Pi toge ther with its chemical shift movement to higher magnetic field, and a decrease in alpha-GP level; and increases in the levels of H-1 signals of lactate, acetate and citrate.