Optimization strategies kinetic approach

In the kinetic approach, the serine or cysteine peptidase rapidly reacts with a suitable acyl donor ester to form the acylenzyme intermediate, which can be deacylated competitively by the added nucleophilic amine component and water. The ratio between aminolysis and hydrolysis of the acyl donor ester is of great importance for the outcome of the synthesis route.This selectivity is essentially determined by the S subsite specificity of the enzyme as shown above. To establish an optimum synthesis strategy, it is useful to know the basic kinetic parameters for the reaction course, in particular those obtained by S subsite mapping are of great importance for planning and optimization of the enzymatic synthesis. 

Ideal reactions for solution-phase parallel synthesis are those that are kinetically and thermodynamically favored, are tolerant of diverse functionality, and have a broad range of reactant tolerance. In this approach, capture resins and extraction procedures are often used for preliminary purification. The solution-phase reaction conditions must be validated in terms of scope and optimal reaction conditions over the range of reactants. Two common strategies for solution libraries involve derivatization of preformed functionalized scaffolds and multicomponent condensation reactions, for example, the Ugi reaction, the Passerini reaction, and the formation of hydroxyamininimides from an ester, a hydrazine, and an epoxide. 

As for enzyme-coupled reaction system, initial rate itself is estimated by kinetic analysis of reaction curve based on numerical integration and NLSF of calculated reaction curves to a reaction curve of interest. Consequently, neither the conversion of indexes nor the optimization of parameters for such conversion is required and the integration strategy can be realized easily. By kinetic analysis of enzyme-coupled reaction curve, there still should be a minimum number of the effective data and a minimum substrate consumption percentage in the effective data for analysis these prerequisites lead to unsatisfactory lower limits of linear response for favourable analysis efficiency (the use of reaction duration within 5.0 min). The classical initial rate method is effective to enzyme-coupled reaction systems when activities of the enzyme of interest are not too high. Therefore, this new approach for kinetic analysis of enzyme-coupled reaction curve can be integrated with the classical initial rate method to quantify enzyme initial rates potentially for wider linear ranges. 

Nin, Y.-S., Vervisch, L., Tao, P.D. An optimization-based approach to detailed chemistry tabnlatimi antomated progress variable definition. Combust. Flame 160, 776-785 (2013) Octme, R., Astaiita, G. Lumping nonlinear kinetics in porous catalysts diffusion-reaction lumping strategy. AIChE J. 39. 288-293 (1993)... 

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