Creative Biolabs provides the unique charybdotoxin phage display library construction service with first-class quality and high diversity for clients all over the world. As a pioneer of charybdotoxin discovery, Creative Biolabs is pleased to offer our most extensive experience and the best services for boosting our clients’ research and project.
Charybdotoxin (CTX) is a kind of neurotoxin isolated from the venom of the Israeli scorpion Leiurus quinquestriatus hebraeus (Deathstalker). It is a 37 amino acid (4 kDa) motif with the molecular formula C176H277N57O55S7. Functionally, charybdotoxin can block the calcium-activated potassium channels, which causes hyperexcitability of the nervous system. In addition, the structure analysis of charybdotoxin indicated an antiparallel triple-stranded β-sheet on one face, a short α-helix on the opposite face and three disulfide bonds in the interior core to form a conformationally stabilized structure. Besides that, it is a perfect example of cysteine-stabilized α-helical (CSH) and β-sheet (CSB) motifs, thus it is also termed as “cysteine-stabilized ab motif”.
Charybdotoxin represents a source of small and stable scaffold which can bind to the biological targets with high affinity and specificity. According to the well-defined structure and function, charybdotoxin is able to be used as a natural scaffold for protein engineering. For instance, β-turn loop randomized charybdotoxin scaffold carried a CD4-like loop, which can serve as an underlying CD4 mimetic tool. The randomized charybdotoxin scaffold shown excellent affinity for HIV-1 gp120, which can lead to novel HIV-1 envelope binding activities and possibly HIV-1 antagonists by blocking the gp120-CD4 interaction (Li et al. 2001). With the modification of metal binding sites, charybdotoxin scaffold is also available to be induced the metal binding activity.
As an improved phage display technology, Hi-Affi™ phage display platform has been used by Creative Biolabs for protein scaffold libraries construction. The technology is based on the expression of the recombinant peptide or protein as a fusion with a coated protein of bacteriophage then displaying on the phage surfaces to select specific binders. Combined with trimer codon technology and NNK method, our Hi-Affi™ phage display technology is more suitable for sorting and isolating the high affinity protein or peptide targets. It is available to expand the library affinity with 100% precise mutant and over 1010 diversity.
Creative Biolabs is dedicated in the research of scaffold protein as well as scaffold library construction. Our most devoted scientists are confident in delivering libraries that meet all required specifications from customers.
Fig. 1 Analysis of side-chain organization on a refined model of charybdotoxin: structural and functional implications. (PDB ID: 2CRD)