Relative virus infectivities. HiL cells were infected with viruses derived from cotransfecting the indicated HIV-luciferase (HIVLuc) construct with the VSV-G expression construct pVSV-G. Infectivities were monitored by luciferase assay of infected cell lysates, and results were normalized to luciferase activities of the corresponding transfected cells. Infectivities were plotted relative to wt HIVLuc levels on a log scale graph and were based on two or more (H87C = 4; H84Y = 3; H84A = 7) independent sets of infections. Note that the 3WT:1A, 1WT:1A, and 1WT:3A bars correspond to cotransfections using different ratios of wt and H84A constructs and that values for the H84E, H84K, and H84C viruses were <0.2% that of wt.