Semiempirical molecular orbital studies of the acylation step in the lipase-catalyzed ester hydrolysis
نویسندگان
چکیده
In this study, we present the results from the semiempirical molecular orbital calculations for the acylation step in the lipase-catalyzed ester hydrolysis. The results reveal that the lowest energy path for the formation of the tetrahedral intermediate is for the serine residue of the catalytic triad to attack the substrate, followed by coupling heavy atom movement and proton transfer. The calculations of four active site models show that the cooperation of the aspartate group and the oxyanion hole is capable of lowering the activation energy by about 16 kcalmol. Our results further suggest that the lipase-catalyzed ester hydrolysis adopts the single proton transfer mechanism.
منابع مشابه
Unexpected Reaction Pathway for butyrylcholinesterase-catalyzed inactivation of “hunger hormone” ghrelin
Extensive computational modeling and simulations have been carried out, in the present study, to uncover the fundamental reaction pathway for butyrylcholinesterase (BChE)-catalyzed hydrolysis of ghrelin, demonstrating that the acylation process of BChE-catalyzed hydrolysis of ghrelin follows an unprecedented single-step reaction pathway and the single-step acylation process is rate-determining....
متن کاملChanges in Enzyme Efficiency During Lipase-Catalyzed Hydrolysis of Canola Oil in a Supercritical Bioreactor
Enzyme efficiency was investigated in the lipase-catalyzed hydrolysis of canola oil in supercritical carbon dioxide (SCCO2). Immobilized lipase from Mucor miehie (Lipozyme IM) was used as the catalyst and the results showed that enzyme efficiency dropped at high pressures indicating a possible change in enzyme microstructure. Therefore, scanning electron microscopy (SEM) was used...
متن کاملA Semiempirical Transition State Structure for the First Step in the Alkaline Hydrolysis of Cocaine. Comparison between the Transition State Structure, the Phosphonate Monoester Transition State Analog, and a Newly Designed Thiophosphonate Transition State Analog
Semiempirical molecular orbital calculations have been performed for the first step in the alkaline hydrolysis of the neutral benzoylester of cocaine. Successes, failures, and limitations of these calculations are reviewed. A PM3 calculated transition state structure is compared with the PM3 calculated structure for the hapten used to induce catalytic antibodies for the hydrolysis of cocaine. I...
متن کاملIntermediate Production of Mono- and Diolein by an Immobilized Lipase from Candida antarctica
Lipase from Candida antarctica, fixed on macroporous acrylic resin, has been used for the intermediate production of mono- and diolein by hydrolysis of triolein. The effect of altering concentrations of triolein and glycerol and the function of the molecular sieve on the hydrolysis reaction of triolein were investigated. The highest hydrolysis yield was observed for the utmost concentration of ...
متن کاملLipase Catalyzed Ester Synthesis for Food Processing Industries
Lipases are one of the most important industrial biocatalyst which catalyzes the hydrolysis of lipids. It can also reverse the reaction at minimum water activity. Because of this pliable nature, it is widely exploited to catalyze the diverse bioconversion reactions, such as hydrolysis, esterification, interesterification, alcoholysis, acidolysis and aminolysis. The property to synthesize the es...
متن کامل