PeptaibolsThree structural characteristics define the group of polypeptides known as peptaibols:
The antomicrobial activity is thought to arise from the peptaibols' membrane activity and their ability to form pores in lipid membranes. The pores so formed are able to conduct ionic species; this conductance leads to the loss of osmotic balance and cell death.
Along with Aib, non standard residues which have been observed include Isovaline (Iva), Hydroxyproline (Hyp) and Ethylnorvaline (Etnor). Aminoisobutyric acid has a high tendency to form helices and this is borne out by the helical structures of the peptaibols.