Stimulation of the differential rate of β-galactosidase synthesis in E. coli by trimethoprim

✍ Scribed by Lacroute, F. ;Stent, G.S.

• Book ID: 104772481
• Publisher: Springer
• Year: 1968
• Tongue: English
• Weight: 524 KB
• Volume: 101
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00436233

✦ Synopsis

It was found that partial inhibition of peptide chain initiation by trimethoprim causes a sigaifieant increase in the differential rate of fl-galactosidase in cultures of E. coli growing in the presence of suboptimal concentrations of a galactoside inducer. This stimulation is not produced by inhibitors of peptide chain growth, such as chloramphenicol and puromycin. Trimethoprim, furthermore, does not cause a significant increase in the differential rate of fl-galactosidase synthesis in E. coli cultures (a) of i + genotype which are fully induced, (b) of fully constitutive i-genotype, (e) of partially constitutive o c genotype, or (d) of noninducible i s genotype. These findings are compatible with the idea that the differential rate of fl-galaetosidase synthesis is regulated by means of an inducer-dependent growth period of a "regulatory" polypeptide.