[Aminoacyl-tRNA-synthetases and their high molecular weight complexes in the regenerating rat liver].

Glutamyl- and lysyl-tRNA synthetase activities in total preparations and high-molecular complexes from rat liver increase 21 h after partial hepatectomy. Glutamyl-tRNA synthetase has been highly purified from normal and regenerating liver. Km, Vmax values and molecular activity were practically the same for both enzyme preparations. Total methyltransferase activity and that as a part of high-molecular complexes increase 1.5 fold 21 h after the operation but the changes of individual methyltransferase activities differ. The level of tRNA methylation in vivo is also higher during regeneration. Proteinkinases of high-molecular complexes from regenerating liver are sensitive to cyclic AMP and GMP in contrast to control.