virus cpe the tests were read after six days it was revealed that one of the fragments showed the highest inhibition of virus this one was considered the hsv 2 virus inhibitor peptide or the active domain of herpoxin protein the most active fragment became herp was sequenced for its amino acids composition was found to consist of 13 amino acids the sequence for the most active fragment from the n terminal was found to be asn leu tyr gln phe lys asn met ile gln gln phe leu synthetic herp of 13 amino acids was constructed to provide two additional synthetic versions of herp were made having 10 and 5 amino acids from the n terminal the synthetic herp of 10 amino acids provided all versions displayed some antiviral activity it was revealed that the synthetic peptide consisting of 10 amino acids seq id no 2 exhibited the most inhibition of herpes viruses the sequencing and synthesizing was contracted out to the protein core laboratory of baylor college of medicine houston tex the sequence of the most active synthetic version of herp from n terminal was found to be asn leu tyr gln phe lys asn met ile gln seq id no 2 for comparison herpoxin and the synthetic herps were tested in vero cell cultures infected with hsv 1 or hsv 2 viruses the cells were infected in serial concentrations from 10 2 to 10 8 three wells were used for each concentration after absorption of the virus the cultures were divided into three groups group one received medium containing pbs as a positive control group two received medium containing 10 u03bcg ml of herpoxin natural herp and in the remaining group the medium was incorporated with 10 u03bcg ml synthetic herp syn herp u2014 10 amino.