Helical kink and channel behaviour: a comparative study with the peptaibols alamethicin, trichotoxin and antiamoebin.
Kinks or bends introduced in peptides and proteins by "helical distorter" residues such as proline, other imino acids and glycine, especially when these are in close proximity in the sequence, are increasingly recognized as playing an essential role in the gating of channel-forming peptides as well as of physiological ion channels. Peptaibols are useful simple models for the much more complex biological ion channels, especially voltage-gated ones. In this short review, we compare the monomeric structures of three selected peptaibols (alamethicin, trichotoxin and antiamoebin) that widely differ with regards their near-central kink angles and dipolar moment orientations. These structural features are then shown to be correlated to the different patterns of channel activity, both at the macroscopic and single-channel levels of investigation.
Duclohier
H
H
Interactions Cellulaires et Moléculaires, UMR 6026 CNRS, Université de Rennes I, 35042 Cedex, Rennes, France. herve.duclohier@univ-rennes1.fr
D000408:Alamethicin / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides; D004594:Electrophysiology; D007473:Ion Channels / Q000737:chemistry* / Q000502:physiology; D007700:Kinetics; D008051:Lipid Bilayers / Q000737:chemistry; D008958:Models, Molecular; D054848:Peptaibols; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary
D023181:Antimicrobial Cationic Peptides; D007473:Ion Channels; D008051:Lipid Bilayers; D054848:Peptaibols; D010455:Peptides; C006596:antiamoebin; D000408:Alamethicin; C016161:trichotoxin