Enzymatic coupling

The cyclodextrins are produced by the partial degradation of starch followed by the enzymatic coupling of the glucose units into... 

Kim J-E, E Fernandes, J-M Bollag (1997) Enzymatic coupling of the herbicide bentazon with humus monomers and characterization of reaction products. Environ Sci Technol 31 2392-2398. 

Figure 6.7 Enzymatic coupling to drive aldol reaction equilibrium in the synthetic direction...

There exists a wide variety in the setup of ELISA assays (direct binding or competition setups) and the enzymatic reaction utilized [148]. A similar principle to enhance sensitivity by enzymatic coupling is realized after gel electrophoretic separation of proteins. Here proteins are transferred to nitrocellulose ( western blot ) and detected by antibody-coupled enzymes. 

Figure 3.7 Formation of oligolignols by non-enzymatic coupling of phenoxide radicals.

Electro-generated and regenerated bis(bipyridine)rhodium(I) complexes were able to catalyze the selective non-enzymatically coupled electrochemical generation of NADH from NAD . The direct cathodic reduction even at very negative working potentials leads to the formation of large amounts of enzymatically inactive NAD dimers, while the indirect electrochemical reduction via the rhodium complex acting as... 

F. van Rantwijk, and R. A. Sheldon, Enzymatic coupling using a mixture of side chain donors affords a greener process for ampicillin, Green Chem. 2001, 3, 316-319. 

To enable a covalent labeling of target molecules, the dyes are functionalized with reactive groups. These are either phosphoramidites for the labeling of synthetic oligonucleotides (solid-phase synthesis), or uridine-5 -triphosphates for enzymatic coupling in PCR (random primed labeling... 

Within the natural products field, the investigation of complete biosynthetic pathways at the enzyme level has been especially successful for plant alkaloids of the monoterpenoid indole alkaloid family generated from the monoterpene gluco-side secologanin and decarboxylation product of tryptophan, tryptamine [3-5]. The most comprehensive enzymatic data are now available for the alkaloids ajmalicine (raubasine) from Catharanthus roseus, and for ajmaline from Indian Rauvolfia serpentina [6] the latter alkaloid with a six-membered ring system bearing nine chiral carbon atoms. Entymatic data exsist also for vindoline, the vincaleucoblastin (VLB) precursor for which some studies on enzymatic coupling of vindoline and catharanthine exist in order to get the so-called dimeric Catharanthus indole-alkaloids VLB or vincristine [7-9] with pronounced anti-cancer activity [10, 11]. 

SCHEME 11.2 Synthetic strategies of glycopeptides. (a) Convergent coupling, (b) solid-phase glycopeptide synthesis, and (c) enzymatic coupling. Asp, aspartic acid. 

Sarkar JM, Bollag JM, Malcolm RL (1988) Enzymatic coupling of 2, 4-dichlorophenol to stream fulvic acid in the presence of oxidoreductases. Soil Sci Soc Am J 52 688-694... 

Coupled assays have been used to monitor a variety of different enzymatic reactions and can be split into two types chemically coupled and enzymatically coupled assays. In the former type, the product of the enzymatic reaction under study is detected by reaction with a reactive chemical to allow easy detection of the analyte of interest.23 In enzymatically coupled reactions, the products or substrates of the reaction of interest are acted upon by a second enzyme, creating a tangible readout. One advantage of using such a standardised assay format is that the development of such a method allows the activity of a family of enzymes to be monitored by a single detection method.24,25 The... 

Advances in Enzymatically Coupled Field Effect Transistors... 

Photolithographic Patterning of Enzyme-Immobilized Membranes for Enzymatically Coupled FET... 

Practical Applications of Enzymatically Coupled FET Sensitive to Glucose... 

The enzymatically coupled FET is reviewed in this chapter (32). First, a brief review is given. Determining how to deposit an enzyme-immobilized membrane on the surface of a FET was one of the most difficult problems to solve before tin enzymatically coupled FET could be developed. Therefore, some enzyme-immobilized membrane deposition methods and the photolithographic enzyme-immobilized membrcme patterning method developed by the authors are described in detail. Concomitantly, the performances of some FET biosensors with an enzyme-immobilized membrane made by this method are described. Finally, recent applications of an enzymatically coupled FET are surveyed. 

ADVANCES IN ENZYMATICALLY COUPLED FIELD EFFECT TRANSISTORS... 

An enzymatically coupled FET requires two independent hydrogen ion-sensitive FET elements One carries an enzyme-immobilized membrane on its surface, ctdled an enzyme FET, and the other, with no enzymatic activity, is a reference FET. Figure 4 is a schematic representation of an enzymatically coupled FET (shown in the area surrounded by the broken circle). The enzyme immobilized on the surface of the enzyme FET (EIM in Fig. 4) causes a change in... 

If one wants to mtike an enzymatically coupled FET that is simultaneously sensitive to n chemicals, called a mulufunctional FET biosensor, n + 1 FET elements are needed for its fabrication one reference FET and n enzyme FETs with a different enzyme-immobilized membrane on each gate surface of the n FETs. Each analyte can be detected independently by measuring the differentitd output voltage between the reference FET and the corresponding enzyme FET. 

The first enzymatically coupled FET is sensitive to penicillin (1). It is composed of two separate FET chips and a silver/silver chloride reference electrode (see Fig. 4). Penicillinase, which produces protons during catalysis, is immobilized on one of the FET chips by utilizing the glutaraldehyde protein cross-linking reaction. The membrane of the reference FET chip contains immobilized bovine serum albumin. 

Fig. 4. Schematic representation of

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