1.G.12.2.2
Ebola virus glycoportein 2, GP2, of 676 aas and 2 TMSs, N- and C-terminal.  The NMR structure of the internal fusion loop of 54 aas has been solved (2LCY) The fusion peptide is 17 aas long (Apellániz et al. 2014). The GP2 protein also encodes the GP2-δ peptide of 40 aas which is a viroporin (He et al. 2017). This nonstructural polypeptide, called the delta peptide, is produced in abundance during Ebola virus infection. Full length and conserved C-terminal delta peptide fragments permeabilize the plasma membranes of nucleated cells, increase ion permeability across confluent cell monolayers and permeabilize synthetic lipid bilayers. Permeabilization activity is dependent on the disulfide bond between the two conserved cysteines. The conserved C-terminal portion of the peptide is biochemically stable in human serum, and most serum-stable fragments have full activity (He et al. 2017).