Multiple phenylalanyl-transfer ribonucleic acid synthetase activities in the cytoplasm of Neurospora crassa.
Several tRNA's specific for a particular amino acid have been shown to exist in multiple, or isoaccepting, forms. There is considerable interest in establishing whether multiple aminoacyl-tRNA synthetases also exist. We present evidence that the cytoplasm of Neurospora crassa contains three chromatographically separable phenylalanyl-tRNA synthetases distinct from mitochondrial phenylalanyl-tRNA synthetase. In addition to differences in chromatographic properties the three enzymes exhibit different affinities, in Tris-Cl buffer, toward purified species of valine and alanine tRNA's isolated from Escherichia coli. The two major chromatographic fractions have very similar sedimentation characteristics, which makes a monomer-dimer relationship unlikely.
D002247:Carbon Isotopes; D002845:Chromatography; D003593:Cytoplasm / Q000201:enzymology*; D008025:Ligases; D009491:Neurospora; D010649:Phenylalanine; D012343:RNA, Transfer
D002247:Carbon Isotopes; D010649:Phenylalanine; D012343:RNA, Transfer; D008025:Ligases