Yeast tRNAPhe has been cross-linked photochemically to three aminoacyl-tRNA synthetases, yeast phenylalanyltRNA synthetase, Escherichia coli isoleucyl-tRNA synthetase, and E. coli valyl-tRNA synthetase. The two non-cognate enzymes are known to interact with tRNAPhe. In each complex, three regions on the tRNA are found to cross-link. Two of these are common to all of the complexes, while the thi...

A 500 MHz 1H-n.m.r. study on the semi-synthetic RNA pentadecamer 5'-r(C-A-G-A-Cm-U-Gm-A-A-Y-A-psi-m5C-U-G) comprising the anticodon loop and stem (residues 28-42) of yeast tRNAPhe is presented. By using pre-steady-state nuclear-Overhauser-effect measurements all exchangeable and non-exchangeable base proton resonances, all H1' ribose resonances and all methyl proton resonances are assigned and ...

The crystal structure of yeast t RNAPhe (in the orthorhombic form) is being refined at 3 A resolution in order to obtain a set of atomic coordinates that: (1) fit the X -ray diffraction data and (2) are consistent with the geometry of standard nucleotides and do nO"[ violate non-bonded interactions. Two directions are being taken to obtain the above goal. One is the 'real space refinement' proc...

X-ray crystallagraphic studies studies indicate that there are at least four site-specifically bound hydrated Mg2+ ions, [Mg(H2O)n]2+, in yeast tRNAPhe. The size and the octahedral coordination geometry, rather than the charge, of [Mg(H2O)N]2+ appear to be the primary reasons for the specificity of magnesium ions in site-binding and in the stabilization of the tertiary structure of tRNA.