Streptavidin interaction with

Lee G U, Kidwell D A and Colton R J 1994 Sensing discrete streptavidin-biotin interactions with atomic force microscopy Langmuir 10 354... 

Figure Bl.20.10. Typical force curve for a streptavidin surface interacting with a biotin surface in an aqueous electrolyte of controlled pH. This result demonstrates the power of specific protein interactions. Reproduced with pennission from [81].

Figure 6.2 The trifunctional reagent sulfo-SBED reacts with amine-containing bait proteins via its NHS ester side chain. Subsequent interaction with a protein sample and exposure to UV light can cause crosslink formation with a second interacting protein. The biotin portion provides purification or labeling capability using avidin or streptavidin reagents. The disulfide bond on the NHS ester arm provides cleavability using disulfide reductants, which effectively transfers the biotin label to an unknown interacting protein.

Figure 11.5 At pH 4, the protonated form of iminobiotin does not interact with the binding sites on avidin or streptavidin. At pH 11, the imino group is unprotonated and regains binding capability toward these proteins.

After molecules modified with sulfo-NHS-SS-biotin are allowed to interact with avidin or streptavidin probes, the complexes can be cleaved at the disulfide bridge by treatment with 50 mM DTT. Reduction releases the biotinylated molecule from the avidin or streptavidin capture reagent without breaking the (strept)avidin interaction. The use of disulfide biotinylation reagents... 

FIGURE 5.5 Schematic representations of the two immunosensor formats (a) immunosensor based on the biotin-streptavidin interaction and (b) immunosensor based on rabbit IgG-modified SPCEs. (Reprinted from [27] with permission from Elsevier.)... 

FIGURE 5.6 Schematic representation of the immunosensor based on a Protein A-GEB biocomposite as a transducer, (a) Immobilization of RlgG on the surface via interaction with Protein A, (b) competitive immunoassay using anti-RIgG and biotinylated anti-RIgG, (c) enzyme labeling using HRP-streptavidin and (d) electrochemical enzyme activity determination. (Reprinted from [31] with permission from Elsevier.)... 

Fig. s.n On-line continuous-flow monitoring of biochemical interaction with (a) fluorescence and (b) MS SIM (m/z 390) detection. Fluorescein-biotin (96 nM), streptavidin (32 nM), 20-pL loop injections of 1000 nM biotin (n = 3). MS instrument Q-ToF2 (Waters) equipped with a Waters Z-spray electrospray (ESI) source. Point 1 Carrier pump, protein and reporter ligand pumps... 

The interactions of the dye acceptors to polymers could also be witnessed in the case of solid films. In this case, the sterically more restrictive cavities of the polymeric film 46 allowed better orbital interaction with the smaller and more flexible rhodamine B dye, and accordingly higher energy transfer with rhodamine B-labeled streptavidin was observed compared to Texas Red-... 

Biotin s interaction with the proteins avidin and streptavidin is among the strongest noncovalent affinities known (K l = 1015 M l). The binding occurs between the bicyclic ring of biotin and a pocket within each of the four subunits of the proteins. The valeric acid portion is not involved or required for the interaction (Green, 1975 Wilchek and Bayer, 1988). This characteristic allows modification of the valeric acid side chain without affecting the binding potential toward avidin or streptavidin. 

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