JBC, Vol. 252, Issue 3, 1002-1006, Feb, 1977
Aminoacyl adenylate, a normal intermediate or a dead end in aminoacylation of transfer ribonucleic acid
U. Lagerkvist, B. Akesson and R. Branden
The shape of the time curve for the aminoacylation of tRNA has been
investigated using five different amino acid:tRNA ligases. Four of these
enzymes showed a lag in the time curve during the early phase of the first
catalytic turnover of the enzyme. In each case, the lag period could be
abolished by preincubating the ligase with amino acid, ATP, and Mg2+ under
conditions known to give an aminoacyl adenylate-enzyme complex. With all
five ligases the steady state rate of transfer from the preformed
aminoacyl-adenylate complex to tRNA was approximately the same as that of
the overall reaction.