Preparation of optically pure flurbiprofen via an integrated chemo-enzymatic synthesis pathway

Ground-State Destabilization by Active-Site Hydrophobicity Controls the Selectivity of a Cofactor- Free Decarboxylase

“…This table also shows the corresponding selectivities, kinetics (kcat) and activation free energies estimated based on experimentally measured activities of each variant towards each compound studied here, where experimental data is available. 18,20,23,34,35 From this data, it can be seen that our EVB models only show turnover of compounds 1a, 1b, 1c and 1e, in good agreement with experimental observables, 18,20,23,28,34,35 whereas the activation free energies for compound 1d is very high for the cleavage of both carboxylic groups, suggesting that this compound is not transformed by the enzyme. In cases where experimental data was available to allow for activation free energies to be estimated by experiment, we typically obtain activation barriers within ~3 kcal mol -1 of the experimental value for cleavage of the energetically preferred carboxylate group.…”

“…However, our modeled (S)selectivity is in good agreement with the observation of the pure (S)-enantiomers found in experiments. 18,34 In addition, our calculations reproduce both the expected formation of the (S)enantiomer and the experimental activation free energies for the decarboxylation of compounds 1a through 1c, and 1e by the CLG-IPL variant of AMDase with reasonable quantitative accuracy compared to experiment 18,20,34,35 ( Table 1). We note that this is overall a particularly interesting…”

“…The empirical valence bond (EVB) approach 40 is our methodology of choice in this study, based on the previous successes of both ourselves and others in using this approach to describe enzyme selectivity. [42][43][44][45] In this work, we have performed EVB simulations of the decarboxylation of compounds 1a through 1e (Scheme 2) by wild-type and mutant variants of AMDase, specifically by the CLG-IPL variant (which contains the G74C, V156L, C188G, V43I, A125P, and M159L substitutions) in the case of compounds 1a, 1b, 1c, and 1e, by the G74C/C188G and G74C/C188A variants in the case of compound 1b, and by the G74C/C188G variant in the case of compound 1a and 1c (these variants were selected based on the availability of experimental data 18,20,23,34,35 , with the exception of the G74C/C188A variant for which experimental data is not available). We have provided an in-depth description of our simulation protocol in the Supporting Information, and therefore we only provide here a brief summary of our methodology.…”

“…Shown here are also the experimentally observed selectivities for each compound, as well as the corresponding kinetics (kcat, s -1 ) and activation free energies (∆G ‡ exp) derived from the experimentally observed activities towards each compound by each variant, as presented in refs. 18,20,23,34,35 . The kcat values were either taken directly from the literature, or were estimated by using the relationship kcat = (specific activity x molecular weight).…”

Urease covalently immobilized on cotton-derived nanocellulose-dialdehyde for urea detection and urea-based multicomponent synthesis of tetrahydro-pyrazolopyridines in water

“…Due to the superior specicity and environmental benignity of enzymes compared to traditional chemical catalysts, in vitro enzymatic reactions have been developed in recent academic and industrial research. 1,2 However, enzyme immobilization on proper supports is necessary due to the stability and reusability issues of free enzymes. 3 There are three types: physical adsorption, covalent chemical bonding, and encapsulation methods for enzyme immobilization applied for diagnostic systems with their advantages and drawbacks.…”