Research Article

Structural Basis for Species Selectivity in the HIV-1 gp120-CD4 Interaction: Restoring Affinity to gp120 in Murine CD4 Mimetic Peptides

Figure 1

Sequence comparison and interactions of CD4. (a) Sequence alignment of human and murine CD4 in the region of the immunglobulin-like domain 1 (D1). Nonconserved and conserved residues are shown in black and gray, respectively. The stretch covered by the mCD4-M (residues 22 to 66) peptide is highlighted in green. The position of β-strands is indicated as arrows above the sequence. This alignment represents the final sequence alignment used for homology modeling. Information about alternative alignments and the quality of the resulting models is given in Supplementary Material available online at doi:10.1155/2012/736593. (b) Region of interaction between CD4 and gp120. gp120 is shown in light gray; the different structural parts of CD4 are color coded as follows. The triple-stranded β-sheet of the CD4 domain D1 (termed “core”) is shown in yellow and green. The green color highlights strand C that forms an intermolecular β-sheet with strand β15 of gp120. Loops connecting the β-strands of the core are shown in red, and the C-terminally adjacent strand D is colored in blue.
736593.fig.001a
(a)
736593.fig.001b
(b)