Redox biocatalysis

At present, studies to extend this strategy to other enzymes are being conducted in our groups and we hope that this concept may become an appealing solution to the problem of co-factor regeneration in redox biocatalysis. 

Blank, L.M., lonidis, G., Ebert, B.E., Buhler, B., and Schmid, A. (2008) Metabolic response of Pseudomonas putida during redox biocatalysis in the presence of a second octanol phase. FEBSJ., 275 (20), 5173-5190. 

Meyer D, Buhler B, Schmid A (2006) Process and catalyst design objectives for specific redox biocatalysis. Adv Appl Microbiol 59 53-91... 

Sahng HL, Jae HK, Park CB (2013) Coupling photocatalysis and redox biocatalysis toward biocatalyzed artificial photosynthesis. Chem Em J 19 4392-4406... 

Gamenara, D., Seoane, G.A., Saenz-Mendez, P., and Dominguez de Maria, P. (2012) Redox Biocatalysis Fundamentals and Applications, 1st edn, John Wiley Sons, Inc., Hoboken. 

Gamenara D, Seoane G, Mendez PS, Dominguez de Maria P (2012) Redox biocatalysis fundamentals and applications. Wiley, Hoboken... 

S. Kara, D. Spickermann, J.H. Schrittwieser, C. Leggewie, W.LH. van Berkel, l.W.C.E. Arend, F. Hollmann, More efficient redox biocatalysis by utilising 1,4-butanediol as a smart cosubstrate, Green Chem. 15 (2013) 330-335. 

With biocatalysis becoming increasingly accepted in synthetic organic chemistry on both the laboratory and industrial scale, there is a huge need for new complexes that can utilize electrons or hydrogen as redox equivalents in cofactor reduction. These redox equivalents are very inexpensive, readily available, and produce no side products, which in turn significantly facilitates the downstream processing of products. 

Combinatorial biocatalysis, where redox enzymes are used in mulit-component systems for new molecule discovery. 

Relatively complex compounds with two stereogenic centers, such as enantiopure diols, can also be synthesized using biocatalysis in reaction sequences starting from readily available building blocks. This can be demonstrated by combining an enzymatic C-C bond formation and a redox reaction in a cascade of two membrane reactors (see Fig. 3.1.5) [1, 21]. 

For peroxidase biocatalysis, the relevant redox couples are Compound I and Compound II, the intermediates present during the catalytic cycle, as described in Chap. 5. However, Fe(III)/Fe(II) redox potential could still be a useful indicator of the oxidizing character of peroxidases. Millis et al. [54] suggested for the first time that the noncatalytic Fe(III)/Fe(II) redox potential could be used to predict the oxidative capacity of a heme peroxidase during turnover. In this work, it was suggested that a more positive Fe(III)/Fe(II) redox potential indicates a higher electron deficiency within the active site, and thus the existence of enzymatic... 

In MET, the thermodynamic redox potentials of the enzyme and the mediator should be accurately matched. The tuning of these potentials is of critical importance to EFC design as this will have a major bearing on cell voltage and catalytic current. When compared to the redox potential of the enzyme, the mediator should have a redox potential that is more positive for oxidative biocatalysis (at anode) and more negative for reductive biocatalysis (at cathode). For efficient electron transfer. 

In this case. Equation (8.26) and the irreversible Uni Uni kinetic scheme for four catalytic sites is appropriate for the steady state kinetic analysis of homo-tetrameric, human mitochondrial MnSOD biocatalysis (Figure 8.8, Table 8.1) with one catalytic site containing one manganese ion per subunit. These sites are not only independent, but each turnover of a catalytic site involves one substrate superoxide radical being transformed to only one of two possible redox products depending upon the oxidation state of the manganese ion involved. 

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