Amino acid activation in mammalian brain. Purification and characterization of tryptophan-activating enzyme from buffalo brain.

ABSTRACT: l-Tryptophan-activating enzyme [l-tryptophan-tRNA ligase (AMP), EC 6.1.1.2] of water-buffalo brain was purified to near homogeneity by heat and pH treatments, ammonium sulphate fractionation, column chromatography on DEAE-cellulose, hydroxyapatite and Amberlite CG-50, and gel filtration on Sephadex G-200. The purified enzyme catalyses tryptophanyl-tRNA formation with yeast tRNA, but not with Escherichia coli tRNA. The enzyme exhibits multiple peaks of activity in Sephadex gel filtration with molecular weights corresponding to 155000, 105000 and 50000. However, only one peak of activity with molecular weight of 155000 can be detected when the enzyme is subjected to gel filtration at high concentration. Disc gel electrophoresis in the presence of sodium dodecyl sulphate reveals a single band

SUBMITTER: Liu CC 

PROVIDER: S-EPMC1165832 | biostudies-literature | 1973 Oct

REPOSITORIES: biostudies-literature