Engineering novel mini-proteins by the transfer of active sites to small disulfide stabilized natural scaffolds

摘要: We have recently proposed a strategy to engineer novel active mini-proteins by the transfer of sites small disulfide-stabilized scaffold scorpion toxins [1, 2]. The chosen represents structural motif evolutionary conserved in all toxins, insect defensins and is formed an antiparallel β -sheet joined α-helix three disulfide bonds [3]. According strategy, we engineered metal-binding protein [1] curaremimetic [4], which were obtained transfer, within β-sheet charybdotoxin, essential residues metal binding site carbonic anhydrase central core snake neurotoxin, respectively. two chimeric (37 31 AA, respectively) expressed expected functionality even if affinity for target ligand (metals first case, acetylcholine receptor, second) was lower than that parent protein. Structure resolution 1H NMR 5] revealed chimerae still preserved original α/ fold toxin transferred maintained native-like conformation. Here report engineering CD4 mimetic transferring exposed -hairpin (CDR2) human CD4, principal receptor HIV-1 infection [6], truncated version (27 AA) scyllatoxin [1].