Protein design of a bacterially expressed HIV-1 gp41 fusion inhibitor.
Peptides derived from the carboxyl-terminal heptad repeat of the gp41 envelope glycoprotein ectodomain (C-peptides) can inhibit HIV-1 membrane fusion by binding to the amino-terminal trimeric coiled coil of the same protein. The fusion inhibitory peptide T-20 contains an additional tryptophan-rich sequence motif whose binding site extends beyond the gp41 coiled-coil region yet provides the key determinant of inhibitory activity in T-20. Here we report the design of a recombinant peptide inhibitor (called C52L) that includes both the C-peptide and tryptophan-rich regions. By calorimetry, C52L binds to a peptide mimic of the amino-terminal coiled coil with a Kd of 80 nM, reflecting the large degree of helicity in C52L as measured by circular dichroism spectroscopy. The C52L peptide potently inhibits in vitro infection of human T cells by diverse primary HIV-1 isolates irrespective of coreceptor preference, with nanomolar IC50 values. Significantly, C52L is fully active against T-20-resistant variants in a single-cycle HIV-1 infectivity assay. Moreover, because it can be expressed in bacteria, the C52L peptide might be more economical to manufacture on a large scale than T-20-like peptides produced by chemical synthesis. Hence the C52L fusion inhibitor may find a practical application, for example as a vaginal or rectal microbicide to prevent HIV-1 infection in the developing world.
Deng
Yiqun
Y
Department of Biochemistry, Weill Medical College of Cornell University, New York, New York 10021, USA.
Zheng
Qi
Q
Ketas
Thomas J
TJ
Moore
John P
JP
Lu
Min
M
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology*; D016466:CHO Cells; D002459:Cell Fusion; D002460:Cell Line; D002478:Cells, Cultured; D018920:Coculture Techniques; D006224:Cricetinae; D003412:Cricetulus; D004220:Disulfides / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D015195:Drug Design; D004926:Escherichia coli / Q000235:genetics; D015700:HIV Envelope Protein gp41 / Q000737:chemistry*; D023581:HIV Fusion Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D020128:Inhibitory Concentration 50; D007930:Leucine / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism / Q000821:virology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015202:Protein Engineering / Q000379:methods*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D014364:Tryptophan / Q000737:chemistry; D014779:Virus Replication / Q000187:drug effects
D019380:Anti-HIV Agents; D004220:Disulfides; D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D011993:Recombinant Fusion Proteins; D014364:Tryptophan; D007930:Leucine