Alcohols as enantioselective inhibitors in a lipase catalysed esterification of a chiral acyl donor

Berglund, Per; Holmquist, Mats; Hult, Karl; Högberg, Hans‐Erik

doi:10.1007/bf00134196

Cited by 35 publications

(24 citation statements)

References 35 publications

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“…Phe Phe Phe > 50; ibuprofen 32; naproxen [14,30] lip1 -Phe344Val Phe Val Phe 29; naproxen [30] lip1 -Phe345Val Phe Phe Val 2.6; naproxen [30] lip1 -Phe344,345Val…”

Section: Lip1unclassified

Molecular Basis of Chiral Acid Recognition by Candida rugosa Lipase: X‐Ray Structure of Transition State Analog and Modeling of the Hydrolysis of Methyl 2‐Methoxy‐2‐phenylacetate

et al. 2011

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Lipase from Candida rugosa shows high enantioselectivity toward a-substituted chiral acids such as 2-arylpropionic acids. To understand how Candida rugosa lipase (CRL) distinguishes between enantiomers of chiral acids, we determined the X-ray crystal structure of a transition-state analog covalently linked to CRL. CRL shows moderate enantioselectivity (E = 23) toward methyl 2-methoxy-2-phenylacetate, 1-methyl ester, favoring the (S)-enantiomer. We synthesized phosphonate (R C ,R P S P )-3, which, upon reaction with CRL, mimics the transition state for hydrolysis of (S)-1-methyl ester, the fast-reacting enantiomer. An X-ray crystal structure of this complex shows a catalytically productive orientation with the phenyl ring in the hydrophobic tunnel of the lipase. Phe345 crowds the region near the substrate stereocenter. Computer modeling of the slow-reacting enantiomer examined four possible conformations for the corresponding slow-reacting enantiomer: three conformations where two substituents at the stereocenter have been exchanged relative to the fast-reacting enantiomer and one conformation with an umbrella-like inversion orientation. Each of these orientations disrupts the orientation of the catalytic histidine, but the molecular basis for disruption differs in each case showing that multiple mechanisms are required for high enantioselectivity.

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“…Phe Phe Phe > 50; ibuprofen 32; naproxen [14,30] lip1 -Phe344Val Phe Val Phe 29; naproxen [30] lip1 -Phe345Val Phe Phe Val 2.6; naproxen [30] lip1 -Phe344,345Val…”

Section: Lip1unclassified

Molecular Basis of Chiral Acid Recognition by Candida rugosa Lipase: X‐Ray Structure of Transition State Analog and Modeling of the Hydrolysis of Methyl 2‐Methoxy‐2‐phenylacetate

et al. 2011

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“…This carrier gas is also called mobile phase (N 2 , He) with 1-2 ml/min flow rate. Physical and chemical natures of molecules make them to travel with different speed in a column [20][21][22][23][24][25].…”

Section: Gc-ms Resultsmentioning

confidence: 99%

“…The yield may reach to the 95% by the use of excess amount of alcohols. The recovery achieved was too low as compared to the other (Figures 4 and 5) purifications process [18][19][20].…”

Section: Liquid-liquid Extraction Follower By Recrystallizationmentioning

confidence: 96%

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A Comparative Study of Physical and Chemical Method for Separation of Benzoic Acid from Industrial Waste Stream

Khan¹,

Usman²

2017

J Adv Chem Eng

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Journal of Advanced Chemical EngineeringKhan and Usman, J Adv Chem Eng 2016, 7:1 DOI: 10.4172/2090-4568.1000161 Volume AbstractPhthalic anhydride is manufactured by the partial oxidation of ortho xylene in the presence of V 2 O 5 /TiO 2 catalyst. In the residue, maleic acid, benzoic acid (BA), telluric acid and traces of other organic compounds are present in the by-product stream. There is almost 60% of (BA) in the residue sample, which compels to recover the tremendous amount of (BA), as it is of great importance. The waste stream is in the form of slurry at high temperature and is solidified at room temperature. Benzoic acid was selectively removed from the solid waste of Phthalic anhydride production industry by the processes associated with less intensive parameters as compare to the extraction techniques achieved by, pressurized hot water, supercritical CO 2 extraction, where the required parameters are highly intensive. The separation has been performed by using physical and chemical techniques. In physical methods recrystallization (RE), liquid-liquid extraction (LLE) as well as recrystallization followed by liquidliquid extraction (RE, LLE) and liquid-liquid extraction followed by recrystallization (LLE, RE) have been studied. In another attempt chemical derivatization (CD) has been performed for the purification purposes. The operation has been performed at the atmospheric pressure with operating temperatures of 100°C and 25°C in physical processes (RE) and (LLE) respectively while in chemical derivatization it ranges from 72°C to 100°C. The characterization of the samples was accomplished by GCMS, FTIR and also its melting point was determined. Almost 99% of the purity was achieved by CD, LLE, RE followed LLE and LLE followed by RE.

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“…However, when the ethanol concentration is further increased (ratios: 1:10, 1:15 and 1:20 (mol:mol)) the enantiomeric ratio drops. Berglund et al (1995) observed a drop in E-value upon increasing the concentration of 1-heptanol in the CRL-catalyzed esterification of 2-methyldecanoic acid, which was caused by the fact that heptanol influences V max S and V max R in different ways. So, in our system, two effects (conformational versus kinetic) may be operative simultaneously, which may be the reason for the observed optimum in E-value.…”

Section: E-ratio In Esterification and Hydrolysis Versus Ethanol Concmentioning

confidence: 89%

The effect of ethanol on the kinetics of lipase‐mediated enantioselective esterification of 4‐methyloctanoic acid and the hydrolysis of its ethyl ester

Heinsman

Valente

Smienk

et al. 2001

Biotech & Bioengineering

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The Novozym 435(R) catalyzed esterification and hydrolysis reactions of 4-methyloctanoic acid (ethyl ester) were investigated. In both the hydrolysis and esterification reactions, the increase of ethanol concentration led to an increase in enantiomeric ratio (E). For hydrolysis of the ethyl ester, the E-value increased from 5.5 [0% (v/v) EtOH] up to 12 [20% (v/v) EtOH]. In case of esterification, the E-value was already 16 [14% (v/v) EtOH] and rose to 57 [73% (v/v) EtOH]. When combining these results of esterification and hydrolysis, an enantiomeric ratio of 350 can be estimated for the sequential kinetic resolution of 4-methyloctanoic acid. In this way, enantiopure 4-methyloctanoic acid could be obtained after two consecutive reaction steps.

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Alcohols as enantioselective inhibitors in a lipase catalysed esterification of a chiral acyl donor

Cited by 35 publications

References 35 publications

Molecular Basis of Chiral Acid Recognition by Candida rugosa Lipase: X‐Ray Structure of Transition State Analog and Modeling of the Hydrolysis of Methyl 2‐Methoxy‐2‐phenylacetate

Molecular Basis of Chiral Acid Recognition by Candida rugosa Lipase: X‐Ray Structure of Transition State Analog and Modeling of the Hydrolysis of Methyl 2‐Methoxy‐2‐phenylacetate

A Comparative Study of Physical and Chemical Method for Separation of Benzoic Acid from Industrial Waste Stream

The effect of ethanol on the kinetics of lipase‐mediated enantioselective esterification of 4‐methyloctanoic acid and the hydrolysis of its ethyl ester

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