Immobilization through protein

Microfilament immobilized through interaction with the bulk of the cell cortex via actin binding proteins. 

DNA-Protein. A large number of proteins in nature perform their function by expediting electron transfer, and there is an extensive literature on electron transfer through proteins (see Refs. 122-124 for reviews). Relevant here are the observations that the excess electron has a large range (not readily trapped) [125] while the hole is relatively immobile (trapped by deprotonation at the peptide bond giving amido radicals) [126]. This raises the expectation that electrons but not holes could be transferred from protein to DNA. This has been observed by a number of groups [127-131]. 

As schematically depicted in Figure 5, two different routes are available for immobilizing biotin-labeled enzymes on the support through avidin-biotin complexation. The first procedure employs the biotin-modified surface on which biotin-labeled enzymes are immobilized through avidin as binder protein. For this procedure, the covalent linkage of biotin onto the surface of a carbon electrode and the preparation of biotin-labeled lipid bilayer on electrode have been studied. An alternative way involves the direct modification of an electrode surface with avidin. If avidin could be immobilized directly without loss of the binding activity to biotin, biotin-labeled enzymes could be loaded more easily on the electrode surface. 

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]. 

Gauchet, C., Labadie, G.R., and Poulter, C.D. (2006). Regio- and chemoselective covalent immobilization of proteins through unnatural amino acids. J Am Chem Soc 128 9274-9275. 

Wu P, Brand L. N-terminal modification of proteins for fluorescence measurements. Methods Enzymol. 1997 278 321-330. Gilmore JM, Scheck RA, Esser-Kahn AP, Joshi NS, Erancis MB. N-terminal protein modification through a biomimetic transamination reaction. Angew. Chem. Int. Ed. 2006 45 5307-5311. Christman KL, Broyer RM, Tolstyka ZP, Maynard HD. Site-specific protein immobilization through N-terminal oxime linkages. J. Mater. Chem. 2007 17 2021-2027. 

Kwon Y, Coleman MA, Camarero JA. Selective immobilization of proteins onto solid supports through spUt-intein-mediated protein trans-splicing. Angew. Chem/ Int. Ed. Engl. 2006 45(11) 1726-1729. 

Most of the linker molecular monolayers are stable over broad potential ranges, limited by reductive and oxidative desorption and cleavage of the Au-S bond. The adsorption process can be followed in real time through several intermediate phases, such as reported for cysteamine [38] (and 1-propanethiol [155]). The in situ STM images shown in Figure 2.6 thus offer an overall impression of the microenvironment for immobilized redox proteins in voltammetric action. ... 

Similar to two-hybrid screens, SPRi can be used to detect conditions under which proteins do not interact. The interaction of human papillomavirus E7 protein and retinoblastoma tumor suppressor protein RB was studied by Jung and co-workers [49]. Fifteen hundred protein spots containing immobilized E7 protein were produced, and an interaction with added RB protein was detected using SPR. The addition of a peptide derived from a motif on E7 along with RB has been observed to clearly disrupt the interaction through lack of an SPR signal. The one peptide discussed in this study can easily be replaced with an array of... 

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