Synthetic peptides and proteins as models for pore-forming structure of channel proteins
This chapter discusses a strategy to identify, in the primary structure of channel proteins, segments that determine the functional characteristics of the protein. Amphipathic α-helical segments are identified in the primary structure using secondary structure prediction algorithms. Segments are selected based on sequence similarity between members of a superfamily of channel proteins. Synthesis of the four-helix bundle protein is accomplished by a two-step procedure: the template molecule is synthesized using orthogonal lysine side-chain protection followed by the simultaneous assembly of peptide blocks. Oligomeric clusters of amphipathic α-helices, whether self-assembled in the lipid bilayer or covalently attached to a template molecule in a four-helix bundle configuration, form ionic channels in bilayers. The evidence that fundamental pore properties may be reproduced within a bundle of α-helices representing selected sequences from the primary structure of a channel protein lends credence to the notion that a cluster of amphipathic α-helices constitutes a general pore-forming motif for channel proteins. © 1992, Elsevier Inc. All rights reserved.
Publication Source (Journal or Book title)
Methods in Enzymology
Grove, A., Iwamoto, T., Montal, M., Tomich, J., & Montal, M. (1992). Synthetic peptides and proteins as models for pore-forming structure of channel proteins. Methods in Enzymology, 207 (C), 510-525. https://doi.org/10.1016/0076-6879(92)07036-N