Glucose enzymatic catalysis

Another fundamental idea that has been invoked to explain enzymatic catalysis is that such reactions utilize bifunctional or multifunctional catalysis that is, several functional groups in the active site are properly aligned with the substrate so that concerted catalysis may occur. Mutarotation of tetramethyl glucose is frequently cited as an example of bifunctional catalysis. Lowry and... 

Further findings relevant for the establishment of the chemical nature of enzymatic catalysis and technical apphcation followed within rather short time. Croft-Hill performed the first enzymatic synthesis, that of isomaltose, in 1898, allowing a yeast extract (df-glycosidase) to act on 40% glucose solution (Sumner and Somers, 1953). In 1900 Kastle and Loevenhart found that the hydrolysis of fat and other esters by lipases is a reversible reaction and that enzymatic synthesis can occur in a dilute mixture of alcohol and acid (Sumner and Myiback 1950). This principle was utilized for the synthesis of... 

The extraordinary specificity of enzymatic catalysis is due to the shape recognition. Enzymes are proteins having a stereospecific binding site. At this site, the two reactants (in the above example, D-glucose and oxygen) are brought together in a precise and favorable orientation for the reaction to take place. 

Bourdillon, C. Demaille, C. Moiroux, J. Saveant, J. M. New insights into the enzymatic catalysis of the oxidation of glucose by native and recombinant glucose-oxidase mediated by electrochemically generated one-electron redox cosubstrates. J. Am. Chem. Soc. 1993, 115, 2-10. 

Energy can neither be created nor destroyed. When glucose, for example, is oxidized by combustion to CO2 and H2O, its potential energy is lost as heat. However, cells transform the energy content of this reduced organic compound into a useful form by degrading it in small steps, many of which involve oxidation, to its final form, CO2 and H2O. Each small step is accomplished by enzymatic catalysis, and the steps are linked together as sequences of consecutive reactions. If two reactions take place in the same test tube as... 

The analytical data show that gold catalysis and enzymatic catalysis allow fast and selective aerobic oxidation of glucose according to the same stoichiometry characterized by the formation of hydrogen peroxide as the by-product (Eq. (21.1)) [8]. However, it is not surprising that completely different catalytic systems adopt different reaction mechanisms as shown by the kinetic studies on commercial enzymatic preparations containing /wcose oxidase and catalase [13]. The results of the research support a Michaelis-Menten type mechanism where the kinetic... 

For industrial applications, metal catalysts should be repeatedly recycled or used in continuous mode for a long time. The introduction of gold catalysis in the aerobic oxidation of glucose has opened exciting perspectives Au is a biocompatible, nontoxic metal, which allows even superior productivities with respect to enzymatic catalysis [38], and no leaching problems have been observed using nanometric particles dispersed on different supports [43]. Compared with chemical oxidations, enzymatic catalysis suffers from more plant complexities... 

The key point for successful experiments was the possibility to avoid the use of colloid stabilizers (protecting agents), because glucose itself acts as a stabiliser. With this advantage, the high activity of unprotected particles ( naked particles throughout the text) was discovered and extraordinary TOP values of magnitude similar to enzymatic catalysis were determined [16]. 

No doubt exists that gold catalysis for glucose oxidation is one of the most appeaUng goals. A promising future for this new technology, mainly due to better productivity than with enzymatic catalysis, can be predicted (Scheme 13.10). 

Enzymatic catalysis is also used in the synthesis of l-"C-labeled D-fructose and o-glucose firom mannitol and glucitol, respectively (Ogren and Langstrom 1998). The preparation of S-adenosyl-L-[ C]methionine (Guegen et al. 1982), [ C]epinephrine (Soussain et al. 1984), and [ C]daunorubicin (Eriks-Fluks et al. 1998) are other examples of enzyme catalysis. The nucleosides [ C]thymidine and [ C]-2 -arabino-2 -fluoro-P-5-methyl-uridine have been prepared by enzymes immobilized on hollow fiber membranes using [ C]formaldehyde as the labeled precursor (Hughes and Jay 1995). 

The mostly used methods to monitor LbL deposition on monodisperse PS-latex particles for various substances are SPLS method and microelectrophoresis. Inorganic (magnetite, silica, titania and fluorescent quantum dots) nanoparticles [32-34], lipids [35-37] and proteins (albumin, immunoglobulin and others) [29, 38, 39] were incorporated as building block for shell formation on colloidal particles. In paper [39] the construction of enzyme multilayer films on colloidal particles for biocatalysis was demonstrated. The enzyme multilayers were assembled on submicrometer-sized polystyrene spheres via the alternate adsorption of poly(ethyleneimine) and glucose oxidase. The high surface area bio-multilayer coated particles formed were subsequently utilized in enzymatic catalysis. The step-wise coating of different lipids alternated with polyelectrolytes was performed by adsorption of preformed vesicles onto... 

Beltrame, P., Comotti, M., Della Pina, C., Rossi, M., Aerobic oxidation of glucose I. Enzymatic catalysis, J. CataL 228-282, (2004). 

Wu X, Zhao B, Wu P, Zhang H, Cai C (2009) Effects of ionic liquids on enzymatic catalysis of the glucose oxidase toward the oxidation of glucose. J Phys Chem B 113(40) 13365-13373. doi 10.1021/jp905632k... 

Sucrose acrylate was synthesized by enzymatic catalysis using an enzyme proleather (a protease from Bacillus Sp.) (Patil et al, 1991a). The sucrose acrylate was polymerized using potassium persulfate/hydrogen peroxide to obtain poly(sucrose acrylate). Tokiwa et al (2000) reported esterification of glucose with adipic acid enzymatically and later on effected its polymerization by conventional methods to obtain biodegradable polymers. Similarly, a-D-galactose was acryloylated with vinyl acrylate enzymatically and later polymerized chemically. 

Lu, W.-Y., Lin, G.-Q., Yu, H.-L. et al. (2007) Facile synthesis of alkyl p-D-glucopyranosides from D-glucose and the corresponding alcohols using fruit seed meals. Journal of Molecular Catalysis B Enzymatic, 44, 72-77. 

The preparation and application of SAM systems patterned by STM and their use in catalysis was demonstrated by Wittstock and Schuhmann [123]. The patterning (local desorption) of SAMs from alkane thiols on gold was performed by scanning electrochemical microscopy (SECM), followed by the assembly of an amino-deriva-tized disulfide and coupling of glucose oxidase to form a catalytically active pattern of the enzyme. The enzymatic activity could be monitored/imaged by SECM. 

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