Positively charged gramicidin A based peptides form two types of membrane channels.

Kovalchuk, S. I., Kotova, E. A., Stoilova, T. B., Sychev, S. V., Egorova, N. S., Surovoy, A. Y., … Ivanov, V. T. (2009). Positively charged gramicidin A based peptides form two types of membrane channels. Advances in Experimental Medicine and Biology, 611, 565–566. https://doi.org/10.1007/978-0-387-73657-0_248