Membrane perforation by Entamoeba histolytica: structural implications derived from the sequence of the pore-forming peptide.

The pore-forming peptide amebapore is considered crucial for the cytolytic activity of E. histolytica. Isolation and subsequent molecular cloning of the peptide allowed predictions as to its secondary structure, most of which were confirmed by experimental data. Here, a computer-aided approach is applied to identify, within the peptide, highly amphipathic helical segments predicted to interact with biological membranes. Two putative alpha-helices fulfill the criteria of membrane-seeking domains and in this respect resemble small lytic peptides of various origins.