Effects of Chemical Modification of Lipase on Its Enantioselectivity in Organic Solvents

Ueji, Shinichi; Tanaka, Hiroyuki; Hanaoka, Takahito; Ueda, Ai; Watanabe, Keita; Kaihatsu, Kunihiro; Ebara, Yasuhito

doi:10.1246/cl.2001.1066

Cited by 12 publications

(4 citation statements)

References 26 publications

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“…Indeed, the (1 S ,2 R )-enantiomer of indene oxide is the major epoxidation product with S , S - 1 in acetone, while (1 R ,2 S )-enantiomer is predominantly formed when acetonitrile or water is used as solvent (Table ). Such an inversion has been reported for certain enzymes and catalytic systems …”

Section: Resultsmentioning

confidence: 58%

Dinuclear Manganese Complexes Containing Chiral 1,4,7-Triazacyclononane-Derived Ligands and Their Catalytic Potential for the Oxidation of Olefins, Alkanes, and Alcohols

et al. 2007

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Five new 1,4,7-triazacyclononane-derived compounds, sodium 3-(4,7-dimethyl-1,4,7-triazacyclononan-1-yl)propionate (Na[LMe2R']) as well as the enantiopure derivatives (S)-1-(2-methylbutyl)-4,7-dimethyl-1,4,7-triazacyclononane (S-LMe2R''), SS-trans-2,5,8-trimethyl-2,5,8-triazabicyclo[7.4.01,9]tridecane (SS-LBMe3), (S)-1-(2-hydroxypropyl)-4,7-dimethyl-1,4,7-triazacyclononane (S-LMe2R), and (R)-1-(2-hydroxypropyl)-4,7-dimethyl-1,4,7-triazacyclononane (R-LMe2R), have been synthesized. Reaction of manganese dichloride with the chiral macrocycles S-LMe2R and R-LMe2R in aqueous ethanol gives, upon oxidation with hydrogen peroxide, the brown dinuclear Mn(III)-Mn(IV) complexes which are enantiomers, [Mn2(S-LMe2R)2(mu-O)2]3+ (S,S-1) and [Mn2(R-LMe2R)2(mu-O)2]3+ (R,R-1). The single-crystal X-ray structure analyses of [S,S-1][PF6]3.0.5(CH3)2CO and [R,R-1][PF6]3.0.5(CH3)2CO show both enantiomers to contain Mn(III) and Mn(IV) centers, each of which being coordinated to three nitrogen atoms of a triazacyclononane ligand and each of which being bridged by two oxo and by two chiral hydroxypropyl pendent arms of the macrocycle. The enantiomeric complexes S,S-1 and R,R-1 were found to catalyze the oxidation of olefins, alkanes, and alcohols with hydrogen peroxide. In the epoxidation of indene the enantiomeric excess values attain 13%. The bond selectivities of the oxidation of linear and branched alkanes suggest the crucial step in this process to be the attack of a sterically hindered high-valent manganese-oxo species on the C-H bond.

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Section: Resultsmentioning

confidence: 58%

Dinuclear Manganese Complexes Containing Chiral 1,4,7-Triazacyclononane-Derived Ligands and Their Catalytic Potential for the Oxidation of Olefins, Alkanes, and Alcohols

et al. 2007

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“…The amount of bound Z-proline at all modification degrees was much less than theoretically expected. [27] [23] In addition, all of the amino groups are not accessible for modification, due to crystal structures and the fact that a lysine residue is not likely to be modified because it participates in salt bridge as reported earlier for Rhizomucor miehei, Candida antarctica, and Fusarium solani lipases.…”

Section: Degree Of Modificationmentioning

confidence: 97%

Modification of Porcine Pancreatic Lipase with Z‐Proline

Evran

Telefoncu

2005

Preparative Biochemistry and Biotechnology

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Porcine pancreatic lipase was modified with Z-proline via the constitution of amide bonds between the free amino groups of lipase and the carboxyl groups of Z-proline, which were activated by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). Different amounts of Z-proline were bound to lipase. Modification degree was determined by 2,4,6-trinitrobenzene sulphonic acid (TNBS), by means of the decrease in free amino groups on lipase. The reason for choosing Z-proline was its unique structural characteristics, protected amino groups, and its effect on protein conformation by reducing the flexibility of the lipase molecule, thus achieving stabilization against changes in pH and temperature. After the modification, porcine pancreatic lipase was found to have new physicochemical characteristics, such as optimum alkaline pH stability and thermal stability at elevated temperatures.

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“…As examples, we highlight the introduction of hydrophobic and hydrophilic groups into chymotrypsin which stabilize the enzyme against thermal denaturation [42]. The nonspecific modification, as judged by 2,4,6-trinitrobenzenesulfonic acid (TNBS) titration, of amines in Candida rugosa lipase (CRL) with benzyloxycarbonyl (Z), Z-NO 2 , lauroyl, and acetyl-enhanced enantioselectivity in lipasecatalyzed esterification of 2-(4-substituted phenoxy)propanoic acids with n-BuOH in isopropyl ether [43]. Phosphorylation, glycosylation, and farnesylation are also examples of enzyme modifications modulating their catalytic activity [44].…”

Section: Functionalization Of Enzymesmentioning

confidence: 99%

Practical insights on enzyme stabilization

Silva

Martins

et al. 2017

Critical Reviews in Biotechnology

170

113

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Enzymes are efficient catalysts designed by nature to work in physiological environments of living systems. The best operational conditions to access and convert substrates at the industrial level are different from nature and normally extreme. Strategies to isolate enzymes from extremophiles can redefine new operational conditions, however not always solving all industrial requirements. The stability of enzymes is therefore a key issue on the implementation of the catalysts in industrial processes which require the use of extreme environments that can undergo enzyme instability. Strategies for enzyme stabilization have been exhaustively reviewed, however they lack a practical approach. This review intends to compile and describe the most used approaches for enzyme stabilization highlighting case studies in a practical point of view.

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Effects of Chemical Modification of Lipase on Its Enantioselectivity in Organic Solvents

Abstract: The chemical modification of lipase with the hydrophobic group such as Z (benzyloxycarbonyl) or Z(NO2) (p-nitro-Z) is found to bring about a marked improvement of the enantioselectivity in isopropyl ether and an inversion of the solvent effects on the enantioselectivity.

Cited by 12 publications

References 26 publications

Dinuclear Manganese Complexes Containing Chiral 1,4,7-Triazacyclononane-Derived Ligands and Their Catalytic Potential for the Oxidation of Olefins, Alkanes, and Alcohols

Dinuclear Manganese Complexes Containing Chiral 1,4,7-Triazacyclononane-Derived Ligands and Their Catalytic Potential for the Oxidation of Olefins, Alkanes, and Alcohols

Modification of Porcine Pancreatic Lipase with Z‐Proline

Practical insights on enzyme stabilization

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