nanoCLAMP
In the medical field of
nanobody (PDB: 2W1Q). nanoCLAMPs to specific targets are generated by varying the amino acid sequences and sometimes the length of three solvent exposed, adjacent loops that connect the beta strands making up the beta-sandwich fold, conferring binding affinity and specificity for the target.[1]
Properties
nanoCLAMPs are the first
E. coli, with typical yields in the range of 50 to 300 mg/L culture. Because nanoCLAMPs are devoid of cysteines, an engineered C-terminal cysteine can be used for site-directed conjugation of entities like fluorophores or resins using thiol
-chemistry.
Development and applications
nanoCLAMPs were developed in the laboratories of Nectagen. nanoCLAMP phage display libraries were constructed that contained variations on 16 surface amino acids in three loops with function diversities of approximately 109 variants. These libraries have been screened for binders to target proteins and peptides, typically yielding between 1 and 30 unique binders to the target.[1]
Purified nanoCLAMPs containing a single C-terminal cysteine can be easily conjugated to halo-acetyl activated
thioether bond renders the resins leach-proof. Targets can be purified to apparent homogeneity in a single-step. The polyol-responsive[2] nature of the resins allows the targets to be eluted with 0.75 M ammonium sulfate and 40% propylene glycol at pH 7.9, conditions which have been shown to preserve native structure and protein complexes.[1][3][4][5][6]
nanoCLAMPs have been produced that target
beta-galactosidase, SlyD, and others. Typical binding capacities of resins range from 1 to 4 mg/ml resin. Because nanoCLAMPs readily refold, nanoCLAMP resins can be regenerated multiple times using guanidinium chloride to clean the resin.[1]
References
External links
- Nectagen, Inc., the developer
Engineered monoclonal antibodies and antibody mimetics | ||
|---|---|---|
| Whole antibody |  | |
| Fab fragment | ||
| Variable fragment | ||
| Smaller units | ||
| Intracellular | ||
| Antibody mimetics | ||