The Antibiotic Bicyclomycin Affects the Secondary RNA Binding Site of Escherichia coli Transcription Termination Factor Rho*

  title={The Antibiotic Bicyclomycin Affects the Secondary RNA Binding Site of Escherichia coli Transcription Termination Factor Rho*},
  author={Attila Magyar and Xiangdong Zhang and Harold L Kohn and William Widger},
  journal={The Journal of Biological Chemistry},
  pages={25369 - 25374}
The interaction of Rho and the antibiotic bicyclomycin was probed using in vitro transcription termination reactions, poly(C) binding assays, limited tryptic digestions, and the bicyclomycin inhibition kinetics of ATPase activity in the presence of poly(dC) and ribo(C)10. The approximate I50 value for the bicyclomycin inhibition of transcription termination at Rho-dependent sites within a modified trp operon template was 5 μM. At antibiotic concentrations near the I50 value, bicyclomycin… 

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