Comparison of the thermolability and hydrophobic properties of high- and low-molecular-weight forms of rabbit liver arginyl-tRNA synthetase.
Two preparations with arginyl-tRNA synthetase activity have been obtained from rabbit liver post-microsomal fraction: a) a high-molecular-weight containing the multienzyme aminoacyl-tRNA synthetase complex and b) a low-molecular-weight preparation containing free enzymes. Thermal inactivation of arginyl-tRNA synthetase in both preparations has been compared in a solution which was successively supplemented with tRNA, reduced glutathione, L-ascorbic acid, ZnCl2 and Triton X 100. Moreover, hydrophobic properties of both enzyme preparations have been compared. It was found that the complexed arginyl-tRNA synthetase is more stable than the free enzyme. A role of hydrophobic interactions in the maintenance of the complexed enzyme stability is suggested.
Department of Physiological Chemistry, Medical School, Lublin, Poland.
H
H
Berbeć
A
A
Paszkowska
D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism*; D000818:Animals; D001126:Arginine-tRNA Ligase / Q000378:metabolism*; D002850:Chromatography, Gel; D004795:Enzyme Stability; D005260:Female; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008970:Molecular Weight; D011817:Rabbits; D012995:Solubility; D013696:Temperature
D000604:Amino Acyl-tRNA Synthetases; D001126:Arginine-tRNA Ligase