16197-92-5Relevant articles and documents
The Structural Effect of Benzoate Surfactant Tails on the Activity of Lipoprotein Lipase in Organic Solvent
Oh, Yeonock
, p. 366 - 369 (2020)
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Enhancing the enantioselectivity of lipase in transesterification by substrate matching: an enzyme memory based approach.
Lee,Choi,Kim
, p. 2553 - 2555 (2000)
The substrate matching strategy is described as a new approach for effectively enhancing the lipase enantioselectivity in organic solvent. In the lipase-catalyzed transesterifications of 3a-c, higher enantioselectivities have been achieved using 1a-c, res
Multicomponent thermosensitive systems for biocatalysts
Kapustin,Vikhrov,Gorokhova,Generalova,Kalyazina,Murzabekova,Zubov
, p. 452 - 457 (2005)
Composite matrices based on macroporous silica modified by N-vinylcaprolactam copolymers with diallyldimethylammonium chloride and with 2-hydroxyethyl methacrylate were obtained. Lipase from Pseudomonas fluorescens was immobilized on the obtained material
A mechanistic investigation of the kinetic resolution of secondary aromatic alcohols using a ferrocene-based planar chiral 4-(dimethylamino)pyridine catalyst
Mesas-Sánchez, Laura,Dinér, Peter
, p. 5623 - 5631 (2015)
A detailed computational and kinetic analysis of the acetylation of 1-phenylethanol with acetic anhydride catalyzed by planar chiral 4-(dimethylamino)pyridine (DMAP) catalyst (-)-1 is presented. The study includes a computational investigation of the pote
Immobilization of burkholderia cepacia on pristine or functionalized multi?walled carbon nanotubes and application on enzymatic resolution of (RS)?1?phenylethanol
Dias, Michele R. G.,De Pauloveloso, Alysson,Do Amaral, Lilian F. M.,Betim, Rhaísa T.,Nascimento, Maria G.,Piliss?o, Cristiane
, p. 1876 - 1884 (2018)
The immobilization of Burkholderia cepacia lipase (BCL) on pristine or functionalized multi-walled carbon nanotubes (MWCNTs) was studied in the resolution of (RS)-1-phenylethanol. For the functionalization, three treatments were used, these being in Hsub
Palladium catalysts supported on N-functionalized hollow vapor-grown carbon nanofibers: The effect of the basic support and catalyst reduction temperature
Sahin, Serap,M?ki-Arvela, P?ivi,Tessonnier, Jean-Philippe,Villa, Alberto,Reiche, Sylvia,Wrabetz, Sabine,Su, Dangsheng,Schl?gl, Robert,Salmi, Tapio,Murzin, Dmitry Yu.
, p. 137 - 147 (2011)
The basic N-functionalized vapor-grown carbon nanofibers (N-VGCF) were synthesized by post-treating oxidized VGCFs in gaseous NH3 at high temperature (ammonolysis) prior to Pd addition by sol immobilization. The catalysts were characterized by nitrogen adsorption, hydrogen temperature programmed desorption, adsorption microcalorimetry and by SEM and TEM. Catalytic activity was evaluated in a model reaction, synthesis of (R)-1-phenylethyl acetate starting from hydrogenation of acetophenone to racemic 1-phenylethanol over Pd supported on N-VGCFs, at 70 °C under atmospheric hydrogen pressure in toluene, followed by acylation over an immobilized lipase in the same reaction pot. The main parameters investigated in this work were the role of the basic N-VGCF supports as well as the reduction procedure of the supported Pd catalysts (Pd-N-VGCF). The results revealed that the catalytic activity of the Pd-N-VGCF catalysts was highly dependent on the reduction procedure. The highest desired product yield, 35%, was obtained over a Pd-N-VGCF catalyst when the support was treated at 400 °C with gaseous ammonia prior to Pd addition.
Discovery and Redesign of a Family VIII Carboxylesterase with High (S)-Selectivity toward Chiral sec-Alcohols
Park, Areum,Park, Seongsoon
, p. 2397 - 2402 (2022/02/17)
Highly enantioselective lipase has been widely utilized in the preparation of versatile enantiopure chiral sec-alcohols through kinetic or dynamic kinetic resolution. Lipase is intrinsically (R)-selective, and it is difficult to obtain (S)-selective lipase. Recent crystal structures of a family VIII carboxylesterase have revealed that the spatial array of its catalytic triad is the mirror image of that of lipase but with a catalytic triad that is distinct from lipase. We, therefore, hypothesized that the family VIII carboxylesterase may exhibit (S)-enantioselectivity toward sec-alcohols similar to (S)-selective serine protease, whose catalytic triad is also spatially arrayed as its mirror image. In this study, a homologous enzyme (carboxylesterase from Proteobacteria bacterium SG_bin9, PBE) of a known family VIII carboxylesterase (pdb code: 4IVK) was prepared, which showed not only moderate (S)-selectivity toward sec-alcohols such as 3-butyn-2-ol and 1-phenylethyl alcohol but also (R)-selectivity toward particular sec-alcohols among the substrates explored. Furthermore, the (S)-selectivity of PBE has been significantly improved by rational redesign based on molecular modeling. Molecular modeling identified a binding pocket composed of Ser381, Ala383, and Arg408 for the methyl substituent of (R)-1-phenylethyl acetate and suggested that larger residues may increase the enantioselectivity by interfering with the binding of the slow-reacting enantiomer. As predicted, substituting Ser381with larger residues (Phe, Tyr, and Trp) significantly improved the (S)-selectivity of PBE toward all sec-alcohols explored, even the substrates toward which the wild-type PBE exhibits (R)-selectivity. For instance, the enantioselectivity toward 3-butyn-2-ol and 1-phenylethyl alcohol was improved from E = 5.5 and 36.1 to E = 2001 and 882, respectively, by single mutagenesis (S381F).
Enantioselective resolution of (±)-1-phenylethyl acetate using the immobilized extracellular proteases from deep-sea Bacillus sp. DL-1
Dong, Lu,Qi, Shujuan,Jia, Jianwei,Zhang, Yun,Hu, Yunfeng
, (2021/03/22)
Bacillus sp. DL-1 was isolated from the deep sea of the Western Pacific Ocean and behaved very good resistance to NaCl. The extracellular proteases of Bacillus sp. DL-1 were found to exhibit excellent enantioselectivity for the kinetic resolution of (±)-1-phenylethyl acetate. To improve the stability of the enzyme, the immobilized extracellular proteases were preparated by using 60 g kieselguhr and 1-L crude fermentation broth containing extracellular proteases of Bacillus sp. DL-1, shaking at 25 °C, 200 r/min for 10 h. Every gram of kieselguhr adsorbed 25.7 mg extracellular protease and the enzymatic activity recovery was 79.86%. The immobilized proteases preserved about 35.8% of its activity after 6 repeated uses, which were also used as biocatalyst to asymmetrically hydrolyse (±)-1-phenylethyl acetate for the preparation of (R)-1-phenylethanol and (S)-1-phenylethyl acetate with high optical purities. The effects of pH, temperature, enzyme concentration, substrate concentration, reaction time and additives (metal ions/surfactants) on the resolution were investigated by single factor experiments. Under the optimal reaction conditions (10 mM (±)-1-phenylethyl acetate, 40 mg/mL immobilized extracellular proteases, pH 7.5 (Tris-HCl), 5% (v/v) methanol and 45 °C for 2 h), (R)-1-phenylethanol was generated with the e.e.p being > 97%, and the yield being 53%, respectively. Analogously, under the optimal reaction conditions (10-mM (±)-1-phenylethyl acetate, 360 mg/mL immobilized extracellular proteases, pH 6.0 (PB), 5% (v/v) DMSO and 35 °C for 1.5 h), (S)-1-phenylethyl acetate was generated with the e.e.s being over 99% and the yield being 79%, respectively. Compared with the extracellular proteases from Bacillus sp. DL-2, the immobilized extracellular proteases from Bacillus sp. DL-1 exhibited higher hydrolytic activity and could asymmetrically hydrolyse (±)-1-phenylethyl acetate by using higher substrate concentrations, shorter reaction times to obtain higher yields. Notably, the extracellular proteases of Bacillus sp. DL-1 were demonstrated to behave the same enantio-preference as those of most other reported esterases/lipases. Proteases from deep-sea Bacillus sp. DL-1 are promising biocatalysts for the synthesis of valuable chiral chemicals.
Pickering-Droplet-Derived MOF Microreactors for Continuous-Flow Biocatalysis with Size Selectivity
Liang, Linfeng,Shi, Hu,Tian, Danping,Wang, Jun-Hao,Xue, Nan,Yang, Hengquan,Zhang, Xiaoming
supporting information, p. 16641 - 16652 (2021/10/20)
Enzymatic microarchitectures with spatially controlled reactivity, engineered molecular sieving ability, favorable interior environment, and industrial productivity show great potential in synthetic protocellular systems and practical biotechnology, but their construction remains a significant challenge. Here, we proposed a Pickering emulsion interface-directed synthesis method to fabricate such a microreactor, in which a robust and defect-free MOF layer was grown around silica emulsifier stabilized droplet surfaces. The compartmentalized interior droplets can provide a biomimetic microenvironment to host free enzymes, while the outer MOF layer secludes active species from the surroundings and endows the microreactor with size-selective permeability. Impressively, the thus-designed enzymatic microreactor exhibited excellent size selectivity and long-term stability, as demonstrated by a 1000 h continuous-flow reaction, while affording completely equal enantioselectivities to the free enzyme counterpart. Moreover, the catalytic efficiency of such enzymatic microreactors was conveniently regulated through engineering of the type or thickness of the outer MOF layer or interior environments for the enzymes, highlighting their superior customized specialties. This study provides new opportunities in designing MOF-based artificial cellular microreactors for practical applications.
