title: Rapid purification of threonyl-tRNA synthetase from Saccharomyces carlsbergensis by affinity elution from phosphocellulose.
abstract: Threonyl-tRNA synthetase [EC 6.1.1.3] of Saccharomyces carlsbergensis was highly purified by a simple enzyme-substrate affinity method. After calcium-gel treatment of the crude enzyme extract, ammonium sulfate precipitation, and removal of polynucleotides with DEAE-cellulose, the enzyme was nonspecifically adsorbed onto phosphocellulose (P-cellulose), and then eluted specifically with a linear concentration gradient of threonine tRNA from torula yeast (Candida (Torulopsis) utilis). The enzyme was purified 303-fold from the calcium-gel supernatant. This purification method is very simple and time-saving. The purified enzyme gave a single band on SDS-gel electrophoresis, indicating a molecular weight of 82,000, and exhibited a molecular weight of about 150,000 by gel filtration. This suggests that the enzyme consists of two identical subunits. Some kinetic properties of the pure enzyme are described.
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000302:isolation & purification*; D002846:Chromatography, Affinity; D007700:Kinetics; D008970:Molecular Weight; D012440:Saccharomyces / Q000201:enzymology*; D013056:Spectrophotometry, Ultraviolet; D013914:Threonine-tRNA Ligase / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000604:Amino Acyl-tRNA Synthetases; D013914:Threonine-tRNA Ligase