Enzymatic catalysts, design

Schultz, P.G. (1988) The interplay between chemistry and biology in the design of enzymatic catalysts. Science, 240, 426. 

Antibodies combine some of the best features of synthetic and enzymatic catalysts. By fusing programmable design with the powerful selective forces of biology, this new technology has the potential to provide many valuable tools for stereoselective organic synthesis in the next century. 

The long range objective of our research is the rational design of enzymatic catalysts. In striving toward this goal, the two principal phenomena that must be considered are the acts of binding and of the subsequent intracomplex catalysis. Our research on the binding... 

In principle, several routes exist for enzymatic isomaltose synthesis. With respect to cost-effectiveness it is obvious that one should use substrates like sucrose or starch that can be exploited by dextransucrase (EC 2.4.1.5) or glucoamylase (EC 3.2.1.3), respectively. However, in both cases, isomaltose represents a side product which is released only in small proportions next to dextran or glucose as main products. Realization of higher yields requires extensive time and effort with respect to engineering of reaction and catalyst design. Based on kinetic investigations dextransucrase has been chosen for the production of isomaltose with sucrose as the substrate, and glucose as an acceptor (see Sect. 2.1). 

Schultz, P. G., The Interplay Between Chemistry and Biology in the Design of Enzymatic Catalysts, Science, 240 426-433, 1988. 

Multi-enzymatic catalysts are recognized as the future generation of biocatalysts. They were particularly designed as enzymes encapsulated into hybrid capsules [129]. It has already been proved that the multi-enzymes organization in a single capsule with separated space enhanced the catalytic capacity of the system. Such an example is the dual biocatalyst of formaldehyde and formate dehydrogenases encapsulated in the capsule lumen/wall. It catalyzed the cascade transformation of CO into formaldehyde [132]. Enzymes co-immobilization in separated spaces of the same cavity exhibited higher formaldehyde yields compared to the free enzyme. Also, the recyclability of the biocatalytic system confirmed the superior mechanical stability [132]. 

Inspired by nature s enzymatic catalysts such as cytochrome P450 and processive enzymes such as cellulases and DNA polymerases, many designed supramolecular... 

Novel equipment has made the designing of enzymatic catalysts easier so that enzymes that are more appropriate to catalyze a reaction can be designed (Gavrilescu, 2004). 

It is apparent that the use of enzymatic catalysis continues to grow Greater availabiUty of enzymes, development of new methodologies for thek utilization, investigation of enzymatic behavior in nonconventional environments, and the design and synthesis of new biocatalysts with altered selectivity and increased stabiUty are essential for the successhil development of this field. As more is learned about selectivity of enzymes toward unnatural substrates, the choice of an enzyme for a particular transformation will become easier to predict. It should simplify a search for an appropriate catalyst and help to estabhsh biocatalytic procedures as a usehil supplement to classical organic synthesis. 

This chapter discusses the steps involved in the development and design of a new S02 oxidation catalyst VK69, which was introduced to the market in 1996 by Haldor Topsoe. The strategy and many of the methods are generally applicable to heterogeneous fixed bed catalysts, partly to fluid and slurry bed catalysts, and less relevant for homogeneous catalysts as found in organic synthesis and enzymatic reactions. 

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