Identification of a Chameleon-like pH-Sensitive Segment within the

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Biochemistry 1997, 36, 6874-6884

Identification of a Chameleon-like pH-Sensitive Segment within the Colicin E1 Channel Domain That May Serve as the pH-Activated Trigger for Membrane Bilayer Association† A. Rod Merrill,*,‡ Brian A. Steer,‡,§ Gerry A. Prentice,‡ Mike J. Weller,| and Arthur G. Szabo| Guelph-Waterloo Centre for Graduate Work in Chemistry, Department of Chemistry and Biochemistry, UniVersity of Guelph, Guelph, Ontario N1G 2W1, Canada, and Department of Chemistry and Biochemistry, UniVersity of Windsor, Windsor, Ontario N9B 3P4, Canada ReceiVed January 30, 1997; ReVised Manuscript ReceiVed April 9, 1997X

ABSTRACT: In Vitro, the channel-forming domain of colicin E1 requires activation by acidic pH (