A SYNTHETIC PEPTIDE CORRESPONDING TO A CONSERVED HEPTAD REPEAT DOMAINIS A POTENT INHIBITOR OF SENDAI VIRUS-CELL FUSION - AN EMERGING SIMILARITY WITH FUNCTIONAL DOMAINS OF OTHER VIRUSES

A series of peptides derived from three domains within the fusion prot ein of Sendai virus was synthesized and examined for their potential t o inhibit the fusion of the virus with human red blood cells. These do mains include the 'fusion peptide) and two heptad repeats, one adjacen t to the fusion peptide (SV-163) and the other to the transmembrane do main (SV-473). Of all the peptides tested, only SV-473 was highly inhi bitive. Using fluorescently-labelled peptides, the mechanism through w hich the SV-473 peptide inhibits the haemolytic activity of the virus was investigated, The results suggest that interactions of the active peptide with virion elements and lipid membranes are involved, Since i t has recently been found that synthetic peptides corresponding to put ative coiled-coil domains of the human immunodeficiency virus (HIV) ty pe 1 transmembrane protein gp41 are potent inhibitors of HIV, we discu ss the general property of virus-derived coiled-coil peptides as inhib itors of viral infection.