Effective lowly cytotoxic analogs of an HIV-cell fusion inhibitor, T22 ([Tyr5,12, Lys7]-polyphemusin II).
A tachyplesin peptide analog, T22 ([Tyr5,12, Lys7]-polyphemusin II), and its shortened congener, TW70 (des-[Cys8,13, Tyr9,12]-[D-Lys10, Pro11]-T22) have strong anti-human immunodeficiency virus (HIV) activity, comparable to that of 3'-azido-2', 3'-dideoxythymidine (AZT). T22 and TW70 are extremely basic peptides, containing 5 Arg residues and 3 Lys residues. The number of positive charges might be related in part to high collateral cytotoxicities of T22 and TW70. Here we have synthesized several analogs, in which the number of positive charges has been reduced through amino acid substitutions using Glu or L-citrulline. As a result, several effective compounds have been found which possess higher selectivity indexes (SIs, 50% cytotoxic concentration/50% effective concentration) than those of T22 and TW70. Higher SIs were attributed mainly to a decrease in cytotoxicity.
Tamamura
H
H
Graduate School of Pharmaceutical Sciences, Kyoto University, Japan. tamamura@pharm.kyoto-u.ac.jp/nfujii@pharm.kyoto-u.ac.jp
Arakaki
R
R
Funakoshi
H
H
Imai
M
M
Otaka
A
A
Ibuka
T
T
Nakashima
H
H
Murakami
T
T
Waki
M
M
Matsumoto
A
A
Yamamoto
N
N
Fujii
N
N
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D019380:Anti-HIV Agents / Q000737:chemistry* / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002942:Circular Dichroism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000494:pharmacology; D015497:HIV-1 / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D008561:Membrane Fusion / Q000187:drug effects*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000737:chemistry* / Q000494:pharmacology; D011487:Protein Conformation
D019380:Anti-HIV Agents; D023181:Antimicrobial Cationic Peptides; D004268:DNA-Binding Proteins; D010455:Peptides; D010456:Peptides, Cyclic; C112118:TW 70; C057636:tachyplesin peptide, Tachypleus tridentatus; C076963:T22 protein, synthetic