I. Pastan, R. Perlman
Apr 25, 1969
Citations
0
Influential Citations
74
Citations
Quality indicators
Journal
The Journal of biological chemistry
Abstract
Abstract Cyclic 3',5'-AMP stimulates the rate of tryptophanase synthesis in Escherichia coli treated with tris(hydroxymethyl)aminomethane and ethylenediaminetetraacetic acid and induced with tryptophan. A maximal effect occurs at 4 x 10-4 m cyclic 3',5'-AMP and a half-maximal response at 1.5 x 10-4 m. The action of cyclic 3',5'-AMP is specific for tryptophanase since the over-all rate of protein and RNA synthesis and the synthesis of the biosynthetic enzyme tryptophan synthetase are unaffected. One site of cyclic 3',5'-AMP action appears to be after the transcription of DNA into messenger RNA since increased enzyme synthesis is observed in induced cells in which cyclic 3',5'-AMP is added after messenger RNA synthesis is arrested by actinomycin D, proflavine, or inducer removal. The half-life of the messenger RNA for tryptophanase is 3 min and is unaffected by cyclic 3',5'-AMP. Cyclic 3',5'-AMP also fails to stimulate the conversion of tryptophanase precursor into active enzyme. Thus cyclic 3',5'-AMP appears to act at the level of the polysome to increase the rate of polypeptide synthesis.