What is "alamethicin"

n. (context medicine English) A peptide antibiotic containing the amino acid ''2-aminoisobutyric acid'' that is not found in proteins

Alamethicin is a peptide antibiotic, produced by the fungus Trichoderma viride. It belongs to peptaibol peptides which contain the non-proteinogenic amino acid residue Aib ( 2-aminoisobutyric acid). This residue strongly induces formation of alpha-helical structure. The peptide sequence is:

Ac-Aib-Pro-Aib-Ala-Aib-Ala-Gln-Aib-Val-Aib-Gly-Leu-Aib-Pro-Val-Aib-Aib-Glu-Gln-Phl

(Ac = acetyl, Phl = phenylalaninol, Aib = 2-Aminoisobutyric acid)

In cell membranes, it forms voltage-dependent ion channels by aggregation of four to six molecules.