Harmonic analysis of the fluorescence response of bimane adducts of colicin E1 at helices 6, 7, and 10

Abstract

Background: Colicin E1 forms a voltage-dependent channel in the cytoplasmic membrane of target E. coli cells. Results: Fluorescence analyses reveal that helices 6, 7, and 10 in the membrane-bound colicin E1 are separate amphipathic α-helices with different periodicities. Conclusion: A new model of the closed channel of colicin E1 has been developed. Significance: This study provides new data on the structure of the umbrella model for the channel-forming colicins.© 2013 by The American Society for Biochemistry and Molecular Biology, Inc.