Carboligation reactivity of benzaldehyde lyase (BAL, EC covalently attached to magnetic nanoparticles

TURAL, Bilsen
Turan, Ilke Simsek
Celebi, Bulent
Demir, Ayhan Sıtkı
Epoxy-functionalized Fe3O4-SiO2 core-shell magnetic nanoparticles (epoxy-M-support) were prepared by modification with glycidyloxypropyltrimethoxysilane (GPTMS) and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and fourier transform infrared spectroscopy (FTIR) methods. Pure histidine-tagged recombinant benzaldehydelyase (BAL, EC 4.1.238) was efficiently immobilized onto the epoxy-M-support with covalent binding. An immobilized BAL epoxy-M-support system was tested to catalyze the self and cross condensation reactions of aldehydes, and the kinetic resolution of racemic acyloins. The acyloin products were obtained in high yield and with high enantiomeric excesses (>= 98% ee). The carboligation reactivity of the immobilized enzyme was comparable to that of free enzyme-catalyzed reactions. The covalent immobilization offers high enzyme activity and stability (at least 5 repeats without losing its activity).


In situ DRIFTS characterization of wet-impregnated and sol-gel Pd/TiO 2 for NO reduction with CH4
Karakaş, Gürkan; Ozkan, Umit S. (Elsevier BV, 2002-05-01)
The adsorption/desorption behavior of 2%Pd/TiO2 catalysts synthesized by wet-impregnation and modified sol–gel techniques were examined in NO–CH4–O2 reaction using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The catalyst prepared by the modified sol–gel method showed significantly higher resistance toward oxygen while maintaining a 100% NO conversion. Under NO+CH4+O2 flow, the main adsorbed NO species was identified as the linearly adsorbed NO on metallic palladium (Pd0–NO)...
Melatonin induces opposite effects on order and dynamics of anionic DPPG model membranes
Sahin, Ipek; Severcan, Feride; Kazanci, Nadide (Elsevier BV, 2007-05-27)
The temperature and concentration induced effects of melatonin on anionic dipalmitoyl phosphatidylglycerol (DPPG) multilamellar liposomes (MLVs) were investigated by using Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The results show that melatonin does not perturb the phase transition profile, while a decrease in the main transition temperature (T-m) is noticed at high melatonin concentrations (15, 24 and 30 mol Low concentrations of melatonin (3, 6 and 9 mol ...
Enantioselective synthesis of both enantiomers of 2-amino-2-(2-furyl)ethan-1-ol as a flexible building block for the preparation of serine and azasugars
Demir, Ayhan Sıtkı; Sesenoglu, O; Aksoy-Cam, H; Kaya, H; Aydogan, K (Elsevier BV, 2003-05-16)
The selective conversion of 1-(2-furyl)-2-hydroxyethan-1-one and ethyl 2-(2-furyl)-2-oxo acetate into (E)- and (Z)-oximes and oxime ethers followed by oxazaborolidine-catalyzed enantioselective reduction using different amino alcohols furnished both enantiomers of the important chiral building block 2-amino-2-(2-furyl)ethan-1-ol with an ee of up to 96%.
A new and efficient chemoenzymatic route to both enantiomers of alpha '-acetoxy-alpha-methyl and gamma-hydroxy-alpha-methyl cyclic enones
Demir, Ayhan Sıtkı; Findik, H; Kose, E (Elsevier BV, 2004-03-08)
A chemoenzymatic synthesis of both enantiomers of the pharmacologically interesting alpha'-acetoxy-alpha-methyl and gamma-hydroxy-alpha-methyl cyclic enones starting from alpha-methyl-beta-methoxy cyclic enones is reported. Manganese(Ill) acetate-mediated acetoxylation followed by the enzyme-mediated hydrolysis of alpha'-acetoxy enone provides acetoxy enones 1a and 2a and hydroxy enones 1b and 2b with high enantiomeric excesses in good yields. The reduction of the acetoxy and hydroxy enones furnished both e...
Optical and Vibrational Properties of [Pt@Pb-12](2-), [Ni@Pb-12](2-), and [Ni@Pb-10](2-) Zintl Ion Clusters
Çetin, Asude; Esentürk, Okan; Nalbant Esentürk, Emren (Wiley, 2017-05-10)
The optical and vibrational properties of Pt- and Ni-centered Pb-Zintl-ion clusters have been investigated by UV/Vis and FTIR spectroscopy. Computational studies have been performed to better interpret the experimental data, due to a lack of any FTIR and UV/Vis spectroscopic studies on these clusters or similar ones in the literature. UV/Vis spectroscopic analyses show an asymmetric broad absorption band, with a maximum at 265 nm for both Pt- and Ni-centered Pb clusters. FTIR spectroscopic analysis demonstr...
Citation Formats
B. TURAL, I. S. Turan, S. TURAL, B. Celebi, and A. S. Demir, “Carboligation reactivity of benzaldehyde lyase (BAL, EC covalently attached to magnetic nanoparticles,” TETRAHEDRON-ASYMMETRY, pp. 260–268, 2013, Accessed: 00, 2020. [Online]. Available: