Isolation of a single polypeptide leucyl-tRNA synthetase from bakers' yeast1

摘要

A single polypeptide of leucyl-tRNA synthetase (LRS) has been purified from budding bakers' yeast by a modification of the procedure published earlier. On denaturing polyacrylamide gel electrophoresis LRS was one band corresponding to molecular weight of 120,000±5,000 daltons. Variable amounts of LRS with a similar molecular weight but which dissociated into equal subunits of 58,000 were also isolated. The affinities (K_M) for substrates for this form of the enzyme were similar to those previously reported for the dimeric form of the enzyme.