UC San Diego
Nanoscale sensing methodology via functional control of an ion channel-forming peptide, Gramicidin A
- Author(s): Macrae, Michael X.
- et al.
Gramicidin ion channels are formed by the association of two [Beta]-helix pentadecapeptides, each spanning half the lipid bilayer. A single dimerization event enables the flux of millions of cations across the bilayer per second. This signal amplification allows for the detection and monitoring of events on the single molecule level - a feat seldomly accomplished. Gramicidin is also remarkably simple to use as it both spontaneously self-incorporates into the membrane and forms channels under a broad range of conditions. Lastly, work primarily done by our lab has developed facile synthetic techniques for functional modifications of the native channel structure. This thesis represents a two-fold effort, both in the improved fundamental understanding of gramicidin A, as well as the exploration of this platform's utility as a tool for more applied problems. Through a comprehensive understanding of the influences which a permanent charge affixed to the channel entrance exert on both channel conductance and open channel lifetime, the ability to utilize the functional response to a wide variety of external stimuli has been realized