The biological role o tRNA was first suggested as being the adaptor molecule connecting the code of mRNA to the amino acid specified. This species of the nucleic acid then plays a pivotal role in protein synthesis. The conformation of tRNA is presumed to be a deciding facor in the high degree of specificity shown in protein synthesis. Coordinating the use of 31P NMR, nitroxide spin label EPR and fluorescence measurements specific aspects of tRNA structure are to be studied. The fluorescence and EPR shall focus on precise environments where as 31P NMR will see the entire structure. The spin labels and fluorescent dyes are covalently attached to precise, well defined locations whereas the NMR sees the tertiary interactions of the backbone. The precise areas are bases 8, 37, 47 and 3' terminus, all interesting structural regions of tRNA. The spectra will be measured to show: 1. solvent effects particularity magnesium nd psermine; 2. codon-anticondon interactions; 3. amino acyl tRNA and 4. interactions with ribosomes. Both elongator tRNA (tRNAphe from E. coli and yeast) and initiatior tRNA (tRNAfMet from E. Coli) are to be used enabling comparisons of the two functional varieties of tRNA to be assessed.