Lipid monolayers, interaction with polypeptides

The amino groups of the DAB residues in the cyclic polypeptide portion of the polymyxin molecule are necessary for the antimicrobial activity, which is reduced on acetylation [142]. Removal of the side chain from the molecule also reduces the activity by about 70% [143]. Various techniques have been used to probe the molecular interaction between polymyxin and the membrane components. Few [144] showed that polymyxin interacts with monolayers prepared from lipids and phospholipids of bacterial origin. Penetration of the mono-layers was followed by an increase in surface pressure, and polymyxin E was... 

Snart, R. S., and Sanyal, N. N., 1968, Interaction of polypeptide hormones with lipid monolayers, Biochem. J. 108 369. 

---