Creative Biolabs provides the insect defensin A scaffold library construction service for customers all over the world. Our scientists have developed the powerful Hi-Affi™ phage display platform which ensures our scaffold libraries to obtain 100% precise mutant and over 1010 diversity.
Insect defensin A belongs to a class of small, cysteine-rich antimicrobial peptides primarily active on Gram-positive bacteria. It is a small protease-resistant molecule (4 kDa) secreted by Phormia terranovae larvae in response to bacterial challenges or injuries. Base on 3D structure analysis, insect defensin A is shown constituted by an irregular structure of α-helix and a twisted antiparallel β-sheet folded into a stable architecture by three disulfide bonds. The natural occurring insect defensin A has been reported to participate in innate immunity and exhibit a wide spectra of antimicrobial activity.
However, insect defensin A is a difficult but novel source to display on the surface of phage. One novel scaffold based on insect defensin A has been reconstructed in order to eliminate antimicrobial activity to increase its yield in a bacterial expression system. This optimized scaffold, which is known as 1ICA29, is a 29 amino acids protein (3 kDa) consisting one α-helix and two β-strands and its structure analysis revealed two loop regions stabilized by two disulfide bridges. This reconstruction did not change the original tertiary structure of the molecule, while enabling it to be displayed on the phage coat fusion protein, and to be used as protein scaffold in the construction of a random phage peptide library.
The scaffold libraries of Creative Biolabs are built by Hi-Affi™ phage display platform. This platform is based on an improved exogenous gene expression method come from the traditional phage display technology, the expression of the recombinant peptide or protein as a fusion with a coated protein of bacteriophage. The Hi-Affi™ phage display platform has combined with trimer codon technology and NNK methods for generating peptides and proteins that have novel-binding activities. The ability to create a large repertoire of variants and select the molecules with desired properties has made this platform applicable to a wide range of research projects.
Creative Biolabs always provide the best services with reasonable price for our global customers. With long-term extensive experience in the field of scaffold library construction, our scientists commit to construct the fine qualitied scaffold library with the highest efficiency.
Fig. 1 Refined three-dimensional structure of insect defensin A. (PDB ID: 1ICA)