Eighteen key reductases from baker's yeast (Saccharomyces cerevisiae) have been overproduced in Escherichia coli as glutathione S-transferase fusion proteins. A representative set of alpha- and beta-keto esters was tested substrates (11 total) for each purified protein. The stereoselectivities ester reductions depended both on the identity enzyme substrate structure, some yielded L- D-alcohols with high stereoselectivities. While alpha-keto were generally reduced lower enantioselectivities,...

The effect of confinement on the solid–liquid phase transitions water was studied by using DSC and FT-IR measurements. Enthalpy changes upon melting frozen in MCM-41 SBA-15 were determined as a function pore size found to decrease with decreasing size. point also decreased almost monotonically Analysis Gibbs–Thomson relation basis thermodynamic data showed that there two stages interfacial free energy change after constant region, i.e., below 6.0 nm: gradual down 3.4 nm another small jump...

Enzyme immobilization has been extensively employed in research and industry to improve enzyme stability allow recycling. Broad ranges of chemicals support materials have utilized for immobilization. Recent breakthroughs nanotechnology science influenced technology. Novel approaches enabled us access more benefits, example, excellent activity stability, cost effectiveness, the establishment continuous flow processes. Herewith, this review provides an update on strategies that attracting...

Flow chemistry as well biocatalysis contribute to achieve green industries and sustainable development. Now there is an approach that combines them, called flow biocatalysis, which attracts more attention. In enzyme immobilization plays a powerful role in promoting its This review begins with general introduction of then provides update on the application immobilized enzymes biocatalysis. Oxidation–reduction, hydrolysis–esterification, transferase reaction, condensation, carboxylation,...

Aromatic ketones, β-keto esters, and simple aliphatic ketones were reduced with excellent selectivity to the corresponding (S)-alcohols by using acetone powder of Geotrichum candidum. This method is superior in reactivity stereoselectivity reduction whole-cell. The experimental conditions for system such as ratio biocatalyst substrate, kinds coenzymes, alcohol coenzyme regeneration, buffer, pH, reaction temperature investigated, stability preservability also examined. very convenient...

Enzymes have been used in non-aqueous media to make the reactions and following process more efficient greener. Here, recent progress enzymatic supercritical carbon dioxide is reviewed. Hydrolysisesterification, oxidation-reduction carboxylation are described, including highly enantioselective reactions. Keywords: lipases, hydrolysis, esterification, enantioselectivity

Reduction of methyl ketones by dried cells Geotrichum candidum (APG4) afforded (S)-alcohols in excellent enantiomeric excess (ee), whereas the reduction trifluoromethyl gave corresponding alcohols opposite configuration also ee. The replacement moiety with a group alters both bulkiness and electronic properties, effect which on stereoselectivity was examined. No inversion stereochemistry observed hindered such as isopropyl ketone, while inverted electron-withdrawing atoms chlorine. mechanism...

Ceramide has emerged as a lipid mediator in apoptosis induced by variety of stresses. As we previously showed that the activation AP-1, nuclear transcription factor was indispensable to ceramide-induced human leukemia HL-60 cells (Sawai, H., Okazaki, T., Yamamoto, Okano, Takeda, Y., Tashima, M., Sawada, Okuma, Ishikura, Umehara, and Domae, N. (1995) <i>J. Biol. Chem.</i> 270, 27326–27331), role mechanism heat shock (HS)-increased c-<i>jun</i> expression here investigated. HS increased...

Alcohol dehydrogenase from Geotrichum candidum was found to be active in supercritical carbon dioxide at 10 MPa; high activities and excellent enantioselectivities were observed for the asymmetric reduction of aromatic cyclic ketones.

Recent developments of biocatalytic reduction carbonyl groups are reviewed. Methods to find, prepare and modify the biocatalysts improve productivity enantioselectivity reactions explained. Then, practical applications for asymmetric compounds with various functionalities given, including synthesis pharmaceutically important compounds. Keywords: glutathione S-transferase (GST), Redox Reaction, overexpression, Cofactor-Regenerating Enzymes, Molecular hydrogen, Geotrichum candidum

Ceramide has emerged as a mediator of cell growth, differentiation, and apoptosis in many biological systems. Many kinds stresses are reported to induce with an increase ceramide generation. Here we showed that the intracellular levels increased parallel heat shock (HS)-induced intensity- time-dependent manner, synthetic N-acetylsphingosine (C(2)-ceramide) synergistically enhanced HS-induced HL-60 cells. In order know role generation apoptosis, examined effects C(2)-ceramide on mRNA protein...

Cells of the fungus, Geotrichum candidum, were immobilized on a water-absorbing polymer and used for stereoselective oxidation reduction in an organic solvent using cyclohexanone, cyclopentanol or alkan-2-ols as additive. Enantiomerically pure (R)-1-arylethanols obtained by racemic 1-arylethanols, whereas enantiomerically (S)-1-arylethanols corresponding ketones, contrast to water free cells which (R)- produced low ee.The reaction mechanism was investigated measuring partition substrates...

We identified a rapid and novel system to effectively metabolize large amount of H2O2 in the suspension cells ofScutellaria baicalensis Georgi. In response an elicitor, immediately initiate hydrolysis baicalein 7-O-β-d-glucuronide by β-glucuronidase, released is then quickly oxidized 6,7-dehydrobaicalein peroxidases. Hydrogen peroxide consumed during peroxidase reaction. The β-glucuronidase inhibitor, saccharic acid 1,4-lactone, significantly reduced H2O2-metabolizing ability theScutellaria...

Pyrrole was converted to pyrrole-2-carboxylate in supercritical CO2 using cells of Bacillus megaterium PYR 2910, and the yield carboxylation reaction 12 times higher than that under atmospheric pressure.