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The study presents a new method to identify enzyme inhibitors, which conducts synthesis of the targeted enzyme. This means that a screening method that enhances the ability to detect the best inhibitor is proposed and the key to the method is an irreversible destruction reaction, which destroys weak inhibitors.

Research has been conducted on the polar organic solvents which inactivate lipases. The preparation of the ionic liquids used in the lipase-catalyzed reactions via the addition of the wash with the aqueous sodium carbonate is described.

Research has been conducted on the lipase from Chromobacterium viscosum, a highly regio- and enantioselective catalyst for the diester hydrolysis. The identification of the remote ester group controlling the enantioselectivity has been performed via the combination of the nonsymmetrical diesters and computer modeling.

A study of alpha-chymotrypsin and bovine pancreatic protease is presented. Results demonstrate that these proteases discriminate between cis and trans diastereomers of carboxylic acid methyl esters.

The enantiopreferences of Pseudomonas cepacia lipase (PCL) towards primary alcohols and secondary alcohols are entirely different, but large and medium-sized substituents have a similar approach towards both. The OH of secondary alcohols and CH2OH of primary alcohols are located in opposite directions. A proposed empirical rule determines the rate of reaction of the enantiomers of primary alcohols based on the size of the substituents. The size of the substituent has no specific influence on the enantioselectivity of PCL toward the alcohols.

Examination of the catalytic ability of Candida rugosa lipase (CRL) toward the hydrolysis of esters of 2-substituted carboxylic acids reveals that treatment of 2-propanol increases the enantioselectivity of CRL. Dissolution of CRL in 50% 2-propanol, followed by dialysis increases the activity of CRL and use of the activated CRL for hydrolysis of seven carboxylic acid reveals that enantioselectivity is increased by a factor of 2.3 to 25. Conversion of closed form of CRL to the open form upon treatment with 2-propanol accounts for the increased activity and enantioselectivity.

A comparative study of various hydrolases enables the identification of two hydrolases, Lipase from Candida rugosa (CRL) and cholesterol esterase (CE), exhibiting enantioselectivity in the hydrolysis of pendant acetates in chiral phosphines and phosphine oxides. Both hydrolases exhibit efficient enantioselectivity toward the phosphine oxide ArPhMeP double bond O. Resolution of this phosphine oxide by CRL produces an enantiomerically-enriched starting acetate and a product alcohol, which on stereospecific reduction produces both enantiomers of phosphine ArPhMeP.

A liquid membrane of chloroform and a soluble, diffusible molecule in a chemical model link proton transport and acylphosphate synthesis. The chemical model mimics various properties of biological proton pumps. Carboxyl groups in the biological pump couple proton transport and ATP hydrolysis through acylphosphates and anhydride intermediates of carboxylic acid.

Enzyme-catalyzed hydrolysis facilitated the efficient kinetic resolution of pipecolic acid esters, which were used to synthesize biologically active peptides, alkaloids and immunosuppresants such as FK506. Lipase obtained from Aspergillus niger, had an apparent molecular weight of 32 kDa, and contributed to the enantioselective hydrolysis of octylpipecolate.

X-ray crystallography was used to determine the mechanism by which lipase from Candida rugosa differentiates between enantiomers of menthol. This mechanism may elucidate the structural features in lipases that are associated with enantiorecognition. Phosphonates were covalently linked to the active site serene to imitate the transition state for menthyl ester hydrolysis.

The scissile fatty acyl sequence of the Candida rugosa lipase-inhibitor complex is bound in a hydrophobic channel. The bound lipid has a 'tuning fork' shape. The tetrahedral intermediates of the acylation step centralizes oxyanion hole components and indicates ester hydrolysis. The stereochemistry of ester hydrolysis is same in all lipases.

X-ray structure crystallization of the alcohol binding pocket, L29P, in Pseudomonas fluorescens (SIK WI) aryl esterase (PFE) was carried out to gain insight into the substitution of L29P which creates a hydrogen bond between the enzyme and hydrogen peroxide in the transition state. The molecular modeling proposed that moving the carbonyl group closer to the active site blocks access for larger alcohol moieties but binds [epsi]-caprolactone more tightly.

A subtilisin-catalyzed hydrolysis of a sulfinamide S-N bond in an N-acyl sulfinamide is reported. The results obtained demonstrate that subtilisin Carlsberg catalyzes the unnatural sulfinamide cleavage even when a carboxamide group is available.

The first biocatalytic route to sulfinamides (R-S(O)-NH2) is reported, whose sulfur stereocenter makes them important chiral auxiliaries for the asymmetric synthesis of amines. Molecular modeling suggests that the N-chloroacetyl and N-dihydrocinnamoyl groups mimic a phenylalanine moiety and thus bind the sulfinamide to the active site.