Creative Biolabs provides the high quality SH2/SH3 domain library construction service through our unique Hi-Affi™ phage display technology. This technology enables our scientists to offer high affinity and diversity SH2/SH3 domain libraries for customers’ research and project.
Src homology 2 (SH2) and Src homology 3 (SH3) are the two noncatalytic domains of Src family tyrosine kinases which has similar structural arrangement. SH2 is approximately 100 amino acids long domain contains two α helices and seven β strands. As well as SH3, a smaller domain of about 60 amino acids residues, characterized by a β-barrel fold consists of five or six β-strands arranged as two tightly packed anti-parallel β sheets, short helices may be contained at the linker regions. Both SH2 and SH3 can be found in a variety of signaling molecules, owning to the role of them in kinase regulation, SH2 and SH3 and their ligands have become important signal transduction targets for drug discovery.
In addition, SH2 and SH3 can be used as scaffolds in the protein-peptide interaction field. Both of them have respective specificity for binding with ligands. SH2 domain, which is relatively conserved among all of the Src family kinases, can bind high affinity to ligands possessing a phosphotyrosine (pY) residue followed by a hydrophobic residue at position +3, and available to go through library construction and selection for yielding binders to specific phosphopeptides. Relatively, SH3 domain binds to targets contain a hydrophobic PXXP motif: RXFPXXP or PXFPXR (X can be any amino acid, F represents a hydrophobic residue), which can be used to detect proline-rich peptides containing a poly-proline II helix conformation. In this way, either SH2 or SH3 scaffolds has potential to be developed as molecular diagnostic tools or therapeutic inhibitors.
To obtain the best SH2/SH3 scaffold libraries, Creative Biolabs has developed the advanced Hi-Affi™ phage display platform for library construction. Phage display is a method for displaying exogenous interest gene on the surface of bacteriophage coat proteins, while keeping the relatively independent space conformation and biological activity without affecting the recombinant phage to the infection of the host ability. It has become a major approach in selecting highly specific scaffolds for human therapy. Comparing with other companies, the unique Hi-Affi™ phage display technology of Creative Biolabs adopts the trimer codon technology and NNK method to pursue higher diversity and more precise mutant for high affinity binders sorting. Currently, through this mature technology, our scientists can obtain 100% precise mutant with over 1010 diversity in our library construction service.
Creative Biolabs has been a long-term expert in the field of scaffold library construction. With years of research and development experience, our scientists have generated more than 50 kinds of scaffold libraries for clients all over the world. Therefore, we are confident in facilitating each specific demand from the customers with efficient and high quality service.
Fig. 1 Three-dimensional solution structure of the Src homology 2 domain of c-Abl.(PDB ID: 1AB2 )
Fig. 2 Solution structure and ligand-binding site of the C-terminal SH3 domain of GRB2. (PDB ID: 1GFC )