Participation of the dnaK and dnaJ gene products in phosphorylation of glutaminyl-tRNA synthetase and threonyl-tRNA synthetase of Escherichia coli K-12.

The heat shock proteins DnaK and DnaJ of Escherichia coli participate in phosphorylation of both glutaminyl-tRNA synthetase and threonyl-tRNA synthetase. When cellular proteins extracted from the dnaK7(Ts) and dnaJ259(Ts) mutant cells labeled with 32Pi at 42 degrees C were analyzed by two-dimensional gel electrophoresis, no phosphorylation of these proteins was observed when they were compared with those from wild-type cells.