In vitro synthesis of enzymes of the tryptophan operon of Escherichia coli.

Two active enzymes of the tryptophan operon of E. coli, anthranilate synthetase (product of trp E and trp D) and tryptophan synthetase (EC 4.2.1.20) (product of trp B and trp A), have been synthesized in a DNA-dependent preparation for protein synthesis. Anthranilate synthetase and the two components of tryptophan synthetase (tryptophan synthetase A and B) are made in vitro in equimolar amounts, suggesting that regulation of the translation is similar in vivo and in vitro. Kinetics of the synthesis of the two enzymes suggest that transcription and translation proceed in vitro in a correct temporal sequence.