Isolation of tRNA isoacceptors by affinity chromatography on immobilized bacterial elongation factor Tu.

Elongation factor Tu from Escherichia coli or Thermus thermophilus was immobilized on cyanogen bromide-activated Sepharose. Immobilized elongation factor Tu X GDP could be converted to Tu X GTP, which is able to bind aminoacyl-tRNA. When bulk tRNA from E. coli, baker's yeast, or bovine liver was aminoacylated by one amino acid only, the resulting aminoacyl-tRNA could be separated in one step from the rest of the tRNA using an affinity column of immobilized elongation factor Tu X GTP. Specific tRNA isoacceptors can be isolated in amounts sufficient for gel electrophorectic analysis, sequence determinations, and hybridization experiments.