EFFECT OF AMINO-ACID REPLACEMENTS, ADDITIONS AND DELETIONS ON THE ANTIVIRAL ACTIVITY OF A PEPTIDE DERIVED FROM THE HIV-1 GP41 SEQUENCE

We demonstrated that a synthetic peptide (EWDREINNYTSLIHSLIEESQNQQEKNE QEGGC), designated SJ-2176, corresponding to the HIV-1 IIIB gp41 seque nce (637-666), inhibited HIV-1 replication, virus-induced cell-cell fu sion and cytopathic effects in both CD4(+) T and monocytic cell lines. In this study, we show that lengthening the peptide at either the N- or C-terminus enhanced its activity, while shortening the peptide from either end decreased the antiviral activity. Substitution of consente d residues in SJ-2176 by alanines resulted in a decrease or eliminatio n of antiviral activity. Replacement of arginine nine and lysine in th e peptide by glutamines did not diminish antiviral activity and render ed the peptide resistant to trypsin.