Enzyme hybridization

Metallic nanoparticles and single-walled carbon nanotubes (SWCNTs) exhibit nanoscale dimensions comparable with the dimensions of redox proteins. This enables the construction of NP-enzyme or SWCNT-enzyme hybrids that combine the unique conductivity features of the nanoelements with the biocatalytic redox properties of the enzymes, to yield wired bioelectrocatalyts with large electrode surface areas. Indeed, substantial advances in nanobiotechnology were achieved by the integration of redox enzymes with nanoelements and the use of the hybrid systems in different bioelectronic devices.35... 

Deverre JR, Boutet V, Boquet D, Ezan E, Grassi J, Grognet JM (1997) A competitive enzyme hybridization assay for plasma determination of phosphodiester and phosphorothioate anti-sense oligonucleotides. Nucleic Acids Res 25(18) 3584-3589... 

Willner I Basnar B Willner B, Nanoparticle-enzyme hybrid systems for nanobiotechnology, FEBS J., 2007, 274, 302-309. 

Willner, L, Basnar, B., and Willner, B. (2007) Nanoparticle-enzyme hybrid... 

U.S. 6015783 01/2000 Von der Osten et al.l Novo Nordisk A/S Removal or bleaching of soils/stains from cellulosics with an enzyme hybrid comprised of a catalytically activated amino acid sequence from a noncellulytic enzyme... 

A similar approach was used for the optical detection of phenolic compounds and hydrogen peroxide, using CdTe QDs-enzyme hybrids. For this, mercaptosucdnic add-capped CdTe QDs were first synthesized, after which the horseradish peroxi-dasephenolic compounds by H2O2 to quinone products resulted in an efficient quenching of QD luminescence [197]. 

Entrapped Lipases as Biocatalysts. Confinement within siUca gels does not only protect enzymes against denaturation. It can also provide a chemical surrounding that favors the enzymatic activity. The ability to tailor the matrix properties, by modifying sol-gel chemistry, enables optimization of the bioactivity of encapsulated enzymes. Hybrid materials can be used to control the polarity of the internal environment within the nanopores. Hydrophobic hybrid organic-inorganic materials can then be produced. They are more suitable for the encapsulation of hpophilic enzymes that would not remain functional in polar matrices (Gill, 1998 Brennan, 1999). 

Biosensor in Table 1-8 is a gel entrapping biomolecules, such as proteins, which react with molecules to be analyzed, resulting in a change in spectra of optical absorption or fluorescence (Dave, 1994). Phycobiliprotein-doped gel (Chen, 1996), for instance, presents a sensor based on the change in fluorescence spectrum. Availability of carbon-enzyme hybrid electrodes is discussed with glucose biosensor as a test case (Sampath, 1996). 

The general principle consists of looking for similarities between the DNA of the unidentified strain and the DNA of the reference strain. There are several methods based on various tools and properties of the DNA molecule. The study of restriction polymorphism is based on the specific action of restriction enzymes. Hybridization is based on the ability of single-strand DNA chains to reassemble in double-strand chains. Combining these two methods and varied uses of each method considerably broaden the possibilities of analysis. 

Lei Y, Mulchandani P, Chen W, Wang J, Mulchandani A (2004) Whole cell-enzyme hybrid ampero-metric biosensor for direct determination of organophosphorons nerve agents with p-nitrophe-nyl substituent. Biotechnol Bioeng 85 706-713... 

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