Gupta MN

References (15)

Title : Enhancement of stability of a lipase by subjecting to three phase partitioning (TPP): structures of native and TPP-treated lipase from Thermomyces lanuginosa - Kumar_2015_Sustain.Chem.Process_3_14
Author(s) : Kumar M , Mukherjee J , Sinha M , Kaur P , Sharma S , Singh TP , Gupta MN
Ref : Sustain Chem Process , 3 :14 , 2017
Abstract : Background The lipase enzyme converts long chain acyltriglycerides into di- and monoglycerides, glycerol and fatty acids. The catalytic site in lipase is situated deep inside the molecule. It is connected through a tunnel to the surface of the molecule. In the unbound state under aqueous conditions, the tunnel remains closed. The tunnel can be opened when the enzyme is exposed to a lipid bilayer or a detergent or many hydrophobic/hydrophilic surfaces. Results In the present study, the lipase was subjected to three-phase partitioning (TPP) which consisted of mixing in tert-butanol and ammonium sulphate to the solution of lipase in the aqueous buffer. The enzyme formed an interfacial precipitate between the tert-butanol rich and water rich phases. The stability of the enzyme subjected to TPP was found to be higher (Tm of 80 C) than the untreated enzyme (Tm of 77 C). The activity of the enzyme subjected to TPP (3.3 U/mg) was nearly half of that of the untreated one (5.8 U/mg). However, the activity of the treated enzyme was higher (17.8 U/mg) than the untreated one (8.6 U/mg) when a detergent was incorporated in the assay buffer. Conclusions The structure determination showed that the substrate binding site in the treated enzyme was more tightly closed than that of the untreated protein.
ESTHER : Kumar_2015_Sustain.Chem.Process_3_14
PubMedSearch : Kumar_2015_Sustain.Chem.Process_3_14
PubMedID:
Gene_locus related to this paper: humla-1lipa

Title : Protein-Coated Microcrystals, Combi-Protein-Coated Microcrystals, and Cross-Linked Protein-Coated Microcrystals of Enzymes for Use in Low-Water Media - Mukherjee_2017_Methods.Mol.Biol_1504_125
Author(s) : Mukherjee J , Gupta MN
Ref : Methods Mol Biol , 1504 :125 , 2017
Abstract : Protein-coated microcrystals (PCMC) are a high-activity preparation of enzymes for use in low-water media. The protocols for the preparation of PCMCs of Subtilisin Carlsberg and Candida antarctica lipase B (CAL B) are described. The combi-PCMC concept is useful both for cascade and non-cascade reactions. It can also be beneficial to combine two different specificities of a lipase when the substrate requires it. Combi-PCMC of CALB and Palatase used for the conversion of coffee oil present in spent coffee grounds to biodiesel is described. Cross-linked protein-coated microcrystals (CL-PCMC) in some cases can give better results than PCMC. Protocols for the CLPCMC of Subtilisin Carlsberg and Candida antarctica lipase B (CAL B) are described. A discussion of their applications is also provided.
ESTHER : Mukherjee_2017_Methods.Mol.Biol_1504_125
PubMedSearch : Mukherjee_2017_Methods.Mol.Biol_1504_125
PubMedID: 27770418

Title : Dual bioimprinting of Thermomyces lanuginosus lipase for synthesis of biodiesel - Mukherjee_2016_Biotechnol.Rep.(Amst)_10_38
Author(s) : Mukherjee J , Gupta MN
Ref : Biotechnol Rep (Amst) , 10 :38 , 2016
Abstract : Use of biodiesel as an alternative to non-renewable sources of energy has become an attractive option in recent years. The enzymatic synthesis of biodiesel by transesterification of fats/oils with an alcohol is a much more sustainable route than the chemical method. However, cost effectiveness of the enzymatic route is a major barrier in its commercialization. In this work, a high activity biocatalyst design of Thermomyces lanuginosus lipase is made by dually bioimprinting it with substrate and a surfactant (which is believed to open up the lid covering the active site of the lipase) during precipitation of the lipase in organic solvent. When the lipase was bioimprinted with only the surfactants, 28 U of the enzyme/g of oil could yield 99% biodiesel from soybean oil in about 4 h. However, when dually bioimprinted even very low enzyme load 1.4 U/g of oil, yielded 99% biodiesel within 48 h.
ESTHER : Mukherjee_2016_Biotechnol.Rep.(Amst)_10_38
PubMedSearch : Mukherjee_2016_Biotechnol.Rep.(Amst)_10_38
PubMedID: 28352522

Title : Molecular bioimprinting of lipases with surfactants and its functional consequences in low water media - Mukherjee_2015_Int.J.Biol.Macromol_81_544
Author(s) : Mukherjee J , Gupta MN
Ref : Int J Biol Macromol , 81 :544 , 2015
Abstract : Lipases from Thermomyces lanuginosa (TLL), Candida rugosa (CRL) and Burkholderia cepacia (BCL) were obtained in the 'open lid' form by adding surfactant molecules like n-octyl-beta-d-glucopyranoside (OG), hexadecyl trimethyl ammonium bromide (CTAB), Bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) and triton X-100 for this purpose. The enzymes were 'dried' by precipitating with 4x (v/v) excess of organic solvents. The imprint surfactant molecules were removed by extensive washing with organic solvents. TLL imprinted with 0.05% CTAB showed 11-fold increase in the transesterification activity and was a better preparation to kinetically resolve (+/-)-1-phenylethanol. Fluorescence emission spectra confirmed that Trp89 of the lid was indeed affected during bioimprinting. With CRL, bioimprinting with OG gave 7-fold increase in the transesterification rates and resulted in reversal of enantioselectivity of CRL and gave R-phenylethyl acetate instead of the S-product as with the unimprinted precipitate. Bioimprinted BCL was also a 7-fold better catalyst for transesterification as well as enantioselectivity.
ESTHER : Mukherjee_2015_Int.J.Biol.Macromol_81_544
PubMedSearch : Mukherjee_2015_Int.J.Biol.Macromol_81_544
PubMedID: 26306412

Title : Stabilization of Candida rugosa lipase during transacetylation with vinyl acetate - Majumder_2010_Bioresour.Technol_101_2877
Author(s) : Majumder AB , Gupta MN
Ref : Bioresour Technol , 101 :2877 , 2010
Abstract : An optimally prepared Candida rugosa lipase aggregate cross-linked with bovine serum albumin, was found to overcome acetaldehyde deactivation during transacetylation of a series of benzyl alcohols with vinyl acetate. The formulation, under the same reaction conditions, exhibited 4-30x enhancement in the reaction rate as compared to the celite immobilized lyophilized formulation and 25-133x enhancement as compared to the free lyophilized enzyme depending upon the alcohol chosen. The racemic 1-phenylethanol, taken as one of the alcohols, underwent a more efficient enantioselective transacetylation giving 80% enantiomeric excess of the product, (R)-1-phenylethyl acetate, at 38% conversion (E = 15) within 24h while the enzyme immobilized on celite gave 83% enantiomeric excess at 18% conversion (E = 13) during the same period of time.
ESTHER : Majumder_2010_Bioresour.Technol_101_2877
PubMedSearch : Majumder_2010_Bioresour.Technol_101_2877
PubMedID: 19854046

Title : Purification and properties of the alkaline lipase from Burkholderia cepacia A.T.C.C. 25609 - Dalal_2008_Biotechnol.Appl.Biochem_51_23
Author(s) : Dalal S , Singh PK , Raghava S , Rawat S , Gupta MN
Ref : Biotechnol Appl Biochem , 51 :23 , 2008
Abstract : A Burkholderia cepacia (bacteria) strain, A.T.C.C. 25609, which had been isolated from the bronchial washings of a cystic fibrosis patient, was used to produce lipase. The presence of sodium alginate at an optimal concentration of 8 mg.ml(-1) in the growth medium nearly doubled the production of extracellular lipase activity. The enzyme could be purified with 38-fold purification and 96% activity recovery using a two-step purification protocol. The molecular mass of the purified lipase determined by SDS/PAGE was shown to be 28 kDa. The pH optimum of the purified enzyme was 9 and it was stable up to 12 h at pH 9 and 10. The enzyme has a temperature optimum of 40 degrees C and its half-life (t(1/2)) values were 54 and 46 min at 50 and 60 degrees C respectively. The lipase was found to be stable in the presence of the detergents Tween 20 and Triton X-100. The secondary-structure analysis of lipase by CD spectroscopy showed 52% alpha-helix, 7.7% beta-sheet, 12.6% beta-turn and 27.8% random structure. The lipase was cloned and overexpressed in Escherichia coli. The gene sequence of the cloned lipase was determined and compared with other lipases.
ESTHER : Dalal_2008_Biotechnol.Appl.Biochem_51_23
PubMedSearch : Dalal_2008_Biotechnol.Appl.Biochem_51_23
PubMedID: 18052929
Gene_locus related to this paper: burce-lipaa

Title : Enantioselective transacetylation of (R,S)-beta-citronellol by propanol rinsed immobilized Rhizomucor miehei lipase - Majumder_2007_Chem.Cent.J_1_10
Author(s) : Majumder AB , Shah S , Gupta MN
Ref : Chem Cent J , 1 :10 , 2007
Abstract : BACKGROUND: Use of enzymes in low water media is now widely used for synthesis and kinetic resolution of organic compounds. The frequently used enzyme form is the freeze-dried powders. It has been shown earlier that removal of water molecules from enzyme by rinsing with n-propanol gives preparation (PREP) which show higher activity in low water media. The present work evaluates PREP of the lipase (from Rhizomucor miehei) for kinetic resolution of (R,S)-beta-citronellol. The acylating agent was vinyl acetate and the reaction was carried out in solvent free media.
RESULTS: The PREP, with 0.75% (v/v, reaction media) water, was indeed found to be more efficient and gave 95% conversion to the ester. Using this PREP, with no added water, 90% ee for (R)-(+)-beta-citronellyl acetate at 45% conversion (E = 42) was obtained in 4 h. The control with freeze-dried enzyme, with zero water content, gave 78% ee at 30% conversion (E = 13). FT-IR analysis showed that PREP had retained the alpha-helical content of the enzyme. On the other hand, freeze-dried enzyme showed considerable loss in the alpha-helical content. CONCLUSION: The results show that PREP may be a superior biocatalyst for enantioselective conversion by enzymes in low-water media.
ESTHER : Majumder_2007_Chem.Cent.J_1_10
PubMedSearch : Majumder_2007_Chem.Cent.J_1_10
PubMedID: 17880741

Title : Kinetic resolution of (+\/-)-1-phenylethanol in [Bmim][PF6] using high activity preparations of lipases - Shah_2007_Bioorg.Med.Chem.Lett_17_921
Author(s) : Shah S , Gupta MN
Ref : Bioorganic & Medicinal Chemistry Lett , 17 :921 , 2007
Abstract : Lipases from two different sources Candida rugosa (CRL) and Burkholderia cepacia (BCL) were formulated as enzyme precipitated and rinsed with organic solvents, organic solvent rinsed enzyme preparation, cross-linked enzyme aggregates (CLEAs) and protein coated micro-crystals (PCMCs). These various enzyme formulates were evaluated for the kinetic resolution of (+/-)-1-phenylethanol in ionic liquid [Bmim][PF(6)] by transesterification with vinyl acetate. Of all the enzyme forms evaluated EPRP and PCMC in the case of CRL showed the best results with 26 % (E value=153) and 53% (E value=79) conversion, respectively, at 35 degrees C in 24h. Carrying out this conversion with PCMC at lower temperature of 25 degrees C further improved the E value to 453 (with 44% conversion in 12h). For BCL the acetone-rinsed enzyme preparation (AREP), CLEA and PCMC performed equally well with % conversion of 50 and 99 ee(p) (%) (E value >1000) in just 2h, whereas, the free lipase gave only 8% conversion.
ESTHER : Shah_2007_Bioorg.Med.Chem.Lett_17_921
PubMedSearch : Shah_2007_Bioorg.Med.Chem.Lett_17_921
PubMedID: 17157018

Title : A high performance lipase preparation: characterization and atomic force microscopy - Shah_2007_J.Nanosci.Nanotechnol_7_2157
Author(s) : Shah S , Sharma A , Varandani D , Mehta B , Gupta MN
Ref : J Nanosci Nanotechnol , 7 :2157 , 2007
Abstract : The goal of obtaining enzyme forms which show greater stability, higher catalytic efficiency, and reusability has been pursued since last several decades. Some novel biocatalyst designs have been evolved and protein coated micro-crystals (PCMCs) is one of them. Pseudomonas cepacia lipase coated micro-crystals were prepared by simultaneous precipitation of mixture of aqueous lipase solution and salts such as potassium sulphate by organic solvents. This resulted in lipase coated micro-crystals. The structures of micro-crystals were studied by atomic force microscopy (AFM). The AFM picture confirmed the enzyme coating over the potassium sulphate crystals. These PCMCs are in the size range of 500-1000 nm. These enzyme coated micro-crystals showed enhanced transesterification rates. Also, the PCMC were stable at 60 degrees C whereas the free enzyme lost all its activity. The enzyme coated micro-crystals prepared by 50 mg Pseudomonas cepacia lipase gave 96% conversion in 90 min whereas free enzyme gave 8% conversion. Even PCMCs prepared from 3.12 mg lipase gave 90% conversion in 10 h at 60 degrees C where as free lipase was inactive at 60 degrees C.
ESTHER : Shah_2007_J.Nanosci.Nanotechnol_7_2157
PubMedSearch : Shah_2007_J.Nanosci.Nanotechnol_7_2157
PubMedID: 17655009

Title : Enhancement of lipase activity in non-aqueous media upon immobilization on multi-walled carbon nanotubes - Shah_2007_Chem.Cent.J_1_30
Author(s) : Shah S , Solanki K , Gupta MN
Ref : Chem Cent J , 1 :30 , 2007
Abstract : BACKGROUND: Immobilization of biologically active proteins on nanosized surfaces is a key process in bionanofabrication. Carbon nanotubes with their high surface areas, as well as useful electronic, thermal and mechanical properties, constitute important building blocks in the fabrication of novel functional materials.
RESULTS: Lipases from Candida rugosa (CRL) were found to be adsorbed on the multiwalled carbon nanotubes with very high retention of their biological activity (97%). The immobilized biocatalyst showed 2.2- and 14-fold increases in the initial rates of transesterification activity in nearly anhydrous hexane and water immiscible ionic liquid [Bmim] [PF6] respectively, as compared to the lyophilized powdered enzyme. It is presumed that the interaction with the hydrophobic surface of the nanotubes resulted in conformational changes leading to the 'open lid' structure of CRL. The immobilized enzyme was found to give 64% conversion over 24 h (as opposed to 14% with free enzyme) in the formation of butylbutyrate in nearly anhydrous hexane. Similarly, with ionic liquid [Bmim] [PF6], the immobilized enzyme allowed 71% conversion as compared to 16% with the free enzyme. The immobilized lipase also showed high enantioselectivity as determined by kinetic resolution of (+/-) 1-phenylethanol in [Bmim] [PF6]. While free CRL gave only 5% conversion after 36 h, the immobilized enzyme resulted in 37% conversion with > 99% enantiomeric excess. TEM studies on the immobilized biocatalyst showed that the enzyme is attached to the multiwalled nanotubes. CONCLUSION: Successful immobilization of enzymes on nanosized carriers could pave the way for reduced reactor volumes required for biotransformations, as well as having a use in the construction of miniaturized biosensensor devices.
ESTHER : Shah_2007_Chem.Cent.J_1_30
PubMedSearch : Shah_2007_Chem.Cent.J_1_30
PubMedID: 18047656

Title : A bioconjugate of Pseudomonas cepacia lipase with alginate with enhanced catalytic efficiency - Mondal_2006_Biochim.Biophys.Acta_1764_1080
Author(s) : Mondal K , Mehta P , Mehta BR , Varandani D , Gupta MN
Ref : Biochimica & Biophysica Acta , 1764 :1080 , 2006
Abstract : A bioconjugate of Pseudomonas cepacia lipase with alginate was prepared by simple adsorption. Atomic force microscope (AFM) images showed that this bioconjugate resulted from adsorption rather than entrapment of the enzyme as enzyme molecules were visible on the gel surface. The soluble bioconjugate exhibited increased enzyme activity in terms of high effectiveness factor (effectiveness factor was 3 for the immobilized preparation) and greater Vmax/Km value (Vmax/Km increased 25 times upon immobilization). This constitutes one of the less frequently observed instances of lipase activation by lid opening as a result of binding to a predominantly hydrophilic molecule. The bioconjugate was also more stable at 55 degrees C as compared to the free enzyme and could be reused for oil hydrolysis up to 4 cycles without any loss in activity. Fluorescence emission spectroscopy showed that the immobilized enzyme had undergone definite conformational changes.
ESTHER : Mondal_2006_Biochim.Biophys.Acta_1764_1080
PubMedSearch : Mondal_2006_Biochim.Biophys.Acta_1764_1080
PubMedID: 16765657

Title : Preparation of cross-linked enzyme aggregates by using bovine serum albumin as a proteic feeder - Shah_2006_Anal.Biochem_351_207
Author(s) : Shah S , Sharma A , Gupta MN
Ref : Analytical Biochemistry , 351 :207 , 2006
Abstract : Addition of bovine serum albumin (BSA) as a proteic feeder facilitates obtaining cross-linked enzyme aggregates (CLEAs) in cases where the protein concentration in the enzyme preparation is low and/or the enzyme activity is vulnerable to the high concentration of glutaraldehyde required to obtain aggregates. CLEAs of Pseudomonas cepacia lipase and penicillin acylase were prepared. CLEA of lipase prepared in the presence of BSA retained 100% activity whereas CLEA prepared without BSA retained only 0.4% activity of the starting enzyme preparation. Lipase CLEA showed 12-fold increase in activity over free enzyme powder when the CLEA was used in transesterification of tributyrin. For the transesterification of Jatropha oil, while free enzyme powder required 8 h and 50 mg lipase to obtain 77% conversion, CLEA required only 6 h and 6.25 mg lipase to obtain 90% conversion. In the case of penicillin acylase, 86% activity could be retained in CLEA prepared with BSA whereas CLEA made without BSA retained only 50% activity. CLEA prepared without BSA lost 20% activity after 8 h at 45 degrees C whereas CLEA with BSA retained full activity. CLEA prepared with BSA showed Vmax/Km of 36.3 min-1 whereas CLEA prepared without BSA had Vmax/Km of 17.4 min-1 only. Scanning electron microscopy analysis showed that CLEAs prepared in the presence of BSA were less amorphous and closer in morphology to CLEAs of other enzymes described in the literature.
ESTHER : Shah_2006_Anal.Biochem_351_207
PubMedSearch : Shah_2006_Anal.Biochem_351_207
PubMedID: 16500610

Title : Alginate-chaperoned facile refolding of Chromobacterium viscosum lipase - Mondal_2006_Biochim.Biophys.Acta_1764_877
Author(s) : Mondal K , Bohidar HB , Roy RP , Gupta MN
Ref : Biochimica & Biophysica Acta , 1764 :877 , 2006
Abstract : Urea denatured lipase from Chromobacterium viscosum lipase could be refolded by addition of alginate with high guluronic acid content. The refolded molecule could be recovered by affinity precipitation. This approach resulted in recovery of 80% (of original activity) as compared to classical dilution method which gave only 21% activity recovery. Dynamic light scattering showed that binding required about 45 min and activity data obtained from affinity precipitation experiments indicated that refolding was almost instantaneous after binding. Circular dichroism (CD) and fluorescence data showed that refolded molecule was identical to the native molecule. It also showed that refolding takes place at the binding stage and not at the precipitation stage. Preliminary studies showed that the refolding strategy worked equally well with lipases from wheat germ and porcine pancreas.
ESTHER : Mondal_2006_Biochim.Biophys.Acta_1764_877
PubMedSearch : Mondal_2006_Biochim.Biophys.Acta_1764_877
PubMedID: 16624637
Gene_locus related to this paper: burgl-lipas

Title : Lipase catalyzed synthesis of benzyl acetate in solvent-free medium using vinyl acetate as acyl donor - Majumder_2006_Bioorg.Med.Chem.Lett_16_4041
Author(s) : Majumder AB , Singh B , Dutta D , Sadhukhan S , Gupta MN
Ref : Bioorganic & Medicinal Chemistry Lett , 16 :4041 , 2006
Abstract : Use of vinyl acetate as acyl donor in transesterification of benzyl alcohol catalyzed by a commercially available lipase (Lipozyme RM IM) gave 100% conversion in 10 min. The excess acyl donor and the enzyme could be recovered and reused. Unlike the chemical catalytic processes, it produced no undesirable side product.
ESTHER : Majumder_2006_Bioorg.Med.Chem.Lett_16_4041
PubMedSearch : Majumder_2006_Bioorg.Med.Chem.Lett_16_4041
PubMedID: 16714111

Title : A microwave-assisted microassay for lipases - Jain_2005_Anal.Bioanal.Chem_381_1480
Author(s) : Jain P , Jain S , Gupta MN
Ref : Anal Bioanal Chem , 381 :1480 , 2005
Abstract : A quick and efficient two-step assay for monitoring and screening lipase activity that uses a microtitre plate is described.
ESTHER : Jain_2005_Anal.Bioanal.Chem_381_1480
PubMedSearch : Jain_2005_Anal.Bioanal.Chem_381_1480
PubMedID: 15798906