The magainins are a class of antimicrobial peptides found in the African clawed frog (Xenopus laevis).[1] The peptides are cationic, generally lack a stable conformation in water but form amphipathic α-helix in membranes; their mechanism against micro-organisms is unclear but they disrupt the cell membranes of a broad spectrum of bacteria, protozoa, and fungi.[2]
Magainin | |
---|---|
Identifiers | |
Symbol | Magainin |
TCDB | 1.C.16 |
OPM superfamily | 211 |
OPM protein | 2mag |
They were independently discovered at around the same time by the labs of Michael Zasloff at the NIH and Dudley H. Williams at the University of Cambridge.[2] They were named by Zasloff, after the Hebrew word for "shield," מגן māgēn (Ashkenazi pronunciation: magain).[3]
Zasloff helped found a company, Magainin Pharmaceuticals (subsequently called Genaera) to develop magainins into drugs.[4] One candidate was an analog of magainin called pexiganan (MSI-78) that the company developed as a topical agent for infected diabetic foot ulcers; in 1999 the FDA rejected the application because pexiganan was not better than standard treatments.[2][5][6] Another company, Dipexium Pharmaceuticals, ran further phase III clinical trials for the same use, which failed in 2016.[7]