Design and properties of N(CCG)-gp41, a chimeric gp41 molecule with nanomolar HIV fusion inhibitory activity.
The design and characterization of a chimeric protein, termed N(CCG)-gp41, derived from the ectodomain of human immunodeficiency virus (HIV), type I gp41 is described. N(CCG)-gp41 features an exposed trimeric coiled-coil comprising the N-terminal helices of the gp41 ectodomain. The trimeric coiled-coil is stabilized both by fusion to a minimal thermostable ectodomain of gp41 and by engineered intersubunit disulfide bonds. N(CCG)-gp41 is shown to inhibit HIV envelope-mediated cell fusion at nanomolar concentrations with an IC(50) of 16.1 +/- 2.8 nm. It is proposed that N(CCG)-gp41 targets the exposed C-terminal region of the gp41 ectodomain in its pre-hairpin intermediate state, thereby preventing the formation of the fusogenic form of the gp41 ectodomain, which comprises a highly stable trimer of hairpins arranged in a six-helix bundle. N(CCG)-gp41 has potential as a therapeutic agent for the direct inhibition of HIV cell entry, as an anti-HIV vaccine, and as a component of a rapid throughput assay for screening for small molecule inhibitors of HIV envelope-mediated cell fusion. It is anticipated that antibodies raised against N(CCG)-gp41 may target the trimeric coiled-coil of N-terminal helices of the gp41 ectodomain that is exposed in the pre-hairpin intermediate state in a manner analogous to peptides derived from the C-terminal helix of gp41 that are currently in clinical trials.
Louis
J M
JM
Laboratories of Chemical Physics and Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, Maryland 20892, USA.
Bewley
C A
CA
Clore
G M
GM
D016475:3T3 Cells; D016915:AIDS Vaccines / Q000096:biosynthesis / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D019380:Anti-HIV Agents / Q000737:chemistry* / Q000494:pharmacology; D001483:Base Sequence; D015704:CD4 Antigens / Q000502:physiology; D002459:Cell Fusion; D002460:Cell Line; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D004220:Disulfides; D015195:Drug Design; D015700:HIV Envelope Protein gp41 / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D015202:Protein Engineering; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D013056:Spectrophotometry, Ultraviolet; D014759:Viral Envelope Proteins / Q000502:physiology
D016915:AIDS Vaccines; D019380:Anti-HIV Agents; D015704:CD4 Antigens; D004220:Disulfides; D015700:HIV Envelope Protein gp41; D011993:Recombinant Fusion Proteins; D014759:Viral Envelope Proteins