Differential inhibition of transcription from σ70‐ and σ32‐dependent promoters by rifampicin

FEBS Letters

Błaszczak, Adam²  Węgrzyn, Alicja²  Liberek, Krzysztof¹  Węgrzyn, Grzegorz³  Szalewska-Pałasz, Agnieszka³ 

[1] Department of Molecular and Cellular Biology, Faculty of Biotechnology, University of Gdańsk, Kładki 24, 80-822 Gdańsk, Poland;Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Laboratory of Molecular Biology affiliated with the University of Gdańsk, Kładki 24, 80-822 Gdańsk, Poland;Department of Molecular Biology, University of Gdańsk, Kładki 24, 80-822 Gdańsk, Poland

关键词: RNA polymerase (Escherichia coli);    Initiation of transcription;    Sigma factor;    Rifampicin;   

DOI  :  10.1016/S0014-5793(98)01449-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rifampicin is an antibiotic which binds to the β subunit of prokaryotic RNA polymerases and prevents initiation of transcription. It was found previously that production of heat shock proteins in Escherichia coli cells after a shift from 30°C to 43°C is not completely inhibited by this antibiotic. Here we demonstrate that while activity of a p _L-lacZ fusion (p _L is a σ⁷⁰-dependent promoter) in E. coli cells is strongly inhibited by rifampicin, a p _groE-lacZ fusion, whose activity is dependent on the σ³² factor, retains significant residual activity even at relatively high rifampicin concentrations. Differential sensitivity to this antibiotic of RNA polymerase holoenzymes containing either the σ⁷⁰ or the σ³² subunit was confirmed in vitro. Since the effects of an antibiotic that binds to the β subunit can be modulated by the presence of either the σ⁷⁰ or the σ³² subunit in the holoenzyme, it is tempting to speculate that binding of various σ factors to the core of RNA polymerase results in different conformations of particular holoenzymes, including changes in the core enzyme.

【 授权许可】

Unknown