Figure 1

Location and phenotype of WL/KD. (A) Location of WL/KD in the context of the gp120-gp41 ectodomain. gp120 was drawn using the coordinates 3JWD [17] and 2QAD [20]. The gp120 core is colored blue, CD4 binding site (CD4bs) and CCR5-binding site (CCR5bs) in cyan and magenta, respectively, gp41 binding site in green. gp41: the DSR (green) and MPER were drawn using the coordinates 1IM7 [21] and 2PV6 [22]. The N- and C-terminal helical segments of the MPER are colored purple and magenta respectively and the interhelical hinge in yellow. The sidechains of the aromatic/hydrophobic face of the MPER that inserts into the lipid phase of the membrane are indicated. FP: fusion peptide. (B) gp120-gp41 association. Lysates of metabolically labeled WT, K601D, WL/KD, W596L or empty vector (No Env) transfected 293T cells (c) and corresponding culture supernatants (s) were immunoprecipitated with pooled IgG from HIV-1-infected persons and protein G-Sepharose. Proteins were analysed by reducing SDS-PAGE and phosphorimaging. (C) Cell-cell fusion activity. 293T effector cells were cotransfected with pCAG-T7 plus pcDNA3.1-AD8env plasmids and then cocultured (18 h, 37°C) with CD4 plus CCR5-expressing BHK21 cells harboring a luciferase reporter plasmid. The mean relative light units (RLU) of a representative experiment are shown. (D) 14-day replication kinetics in U87.CD4.CCR5 cells. Virus produced in 293T cells was normalised for RT activity and used to infect U87.CD4.CCR5 cells. The RT activity of the culture supernatant was measured at days 3, 7, 10 and 14, postinfection. The mean RT activity ± standard deviation of triplicate samples is shown.