Fab binding

Choulier, L., Rauffer-Bruyere, N., Ben Khalifa, M., Martin, F., Vernet, T. andAltschuh, D. (1999), Kinetic analysis of the effect on Fab binding of identical substitutions in a peptide and its parent... 

One of the most important features in the immunosensor design is the proper choice of the immobilization method for keeping the affinity of the antibodies. As was previously demonstrated for Protein A, when the antibodies are immobilized through their Fc fragment to Protein A (or G), their Fab binding sites are mostly oriented away from the solid phase. As Protein A is able to link the Fc region of different antibodies, there is no need to modify the antibody with biotin. As an antecedent, we have previously demonstrated the utility of Protein A biocomposite (ProtA-GEB) for the universal attachment of antibodies with different specificities [54]. 

Recombinant humanized monoclonal antibody fragment (Fab) binds to vascular endothelial growth factor (VEGF)... 

The changes in the resonances of protein G on complex formation allow us to identify the regions of the molecule that are involved in Fab binding as the turn between the strands 1 and 2 of the P-sheet and the first two-thirds of p-strand 2, and the loop following the helix, but not the helix itself. As discussed previously (22), the changes observed in the nmr spectrum on complex formation in solution... 

Table n. Kinetics of Fab binding to biotinylated IL-1PK138C and mutant 1 ... 

Graille M, Stura EA, Housden NG, Beckingham IA, Bottomley SP, Beale D, Taussig MI, Sutton BI, Gore MG, Charbonnier IB Complex between Peptostreptococcus magnus protein L and a human antibody reveals structural convergence in the interaction modes of Fab binding proteins. Structure 2001 9 679-687. 

In planning the incubation with both labeled 1° antibodies, be aware the Fab binding to the 1° antibody is not permanent. For 1 h, the binding is saturated, but after several hours, labeled Fab begins to dissociate with only 75% of the 1° antibody labeled. Thus, labeled 1° antibody must be prepared just before use and follow the incubation fixed with paraformaldehyde to retain the label attached to the antibody. 

Figure 5. Scatchard plot for the clone 4 IgG (O) and clone 4 Fab ( ) binding to Mb adsorbed under the conditions outlined in the text. The surface coverage,, is defined in the following manner ...

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