Journal of Molecular Catalysis B: Enzymatic Journal of Molecular Catalysis B: Enzymatic RSS feedThis is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Production of 5-O- α-glucosylgingerol via glucosylation of 6-gingerol by Ensifer sp. M-26
Publication date: Available online 6 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Rika Matsumoto, Hiroshi Satoh, Makoto Ueda 6-Gingerol ((S)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-3-decanone), the major gingerol present in ginger rhizomes, has been found to prevent fat accumulation and improve blood flow. However, its low solubility in water and strong pungent odor often limit its potential applications such as in functional foods. In order to overcome these disadvantages, we investigated microbial glucosylation of 6-gingerol by the soil bacterium Ensifer sp. M-26. 5-O-α-Glucosylgingero...
Source: Journal of Molecular Catalysis B: Enzymatic - January 7, 2017 Category: Biochemistry Source Type: research

Electro-enzymatic hydroxylation of ethylbenzene by the evolved unspecific peroxygenase of Agrocybe aegerita
This study aims to promote catalyst efficiency via electrochemical in situ supply of H2O2, using an evolved variant of AaeUPO on the example of ethylbenzene hydroxylation. Total turnover numbers of up to 400,000molproduct molAaeUPO −1 and space-time-yields of up to 25gL−1 d−1 were achieved in the electro-enzymatic system. These numbers are in the upper range of published data. The presented system stands out by its very high atom economy. Thus, combining electrochemistry and biocatalysis is one step closer towards the first application of peroxygenases in an industrial process. Graphical abstract (Source: Journal of ...
Source: Journal of Molecular Catalysis B: Enzymatic - December 14, 2016 Category: Biochemistry Source Type: research

Highly efficient resolution of N-hydroxymethyl vince lactam by solvent stable lipase YCJ01
Publication date: Available online 14 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ling Zhu, Fucheng Zhu, Song Qin, Bin Wu, Bingfang He Both optically pure enantiomers of N-hydroxymethyl vince lactam are the key synthons for some important antiviral drugs. The high enantioselective transesterification of N-hydroxymethyl vince lactam was catalyzed by the lipase from Burkholderia ambifaria YCJ01 using vinyl acetate as the acyl donor. Under the optimized conditions, an efficient resolution of N-hydroxymethyl vince lactam in high substrate concentration (300mM; 41.7g/L) was obtained with n...
Source: Journal of Molecular Catalysis B: Enzymatic - December 14, 2016 Category: Biochemistry Source Type: research

Combined docking and molecular dynamics study of lipase catalyzed kinetic resolution of 1-phenylethanol in organic solvents
Publication date: Available online 14 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ashwini C. Mathpati, Bhalchandra M. Bhanage A combined docking and molecular dynamics protocol was applied to investigate kinetic resolution of 1-phenylethanol using Burkholderia cepacia lipase (BCL) in different organic solvents. BCL has open structure compared to other lipases and is found to be more effective in kinetic resolution of primary and secondary alcohols compared to other lipases. The fundamental understanding of the difference in specificity of lipases in esterification/transesterification rea...
Source: Journal of Molecular Catalysis B: Enzymatic - December 14, 2016 Category: Biochemistry Source Type: research

The production of immobilized whole-cell lipase from Aspergillus nomius ST57 and the enhancement of the synthesis of fatty acid methyl esters using a two-step reaction
Publication date: Available online 13 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Naruemon Rakchai, Aran H-Kittikun, Wolfgang Zimmermann The production of immobilized whole-cell lipase from Aspergillus nomius ST57 was optimized by cultivation in 50mL of growth medium with the addition of 100, 0.5×0.5×0.5cm3 pieces of biomass support particles at 150rpm, 30°C for 84hours. The hydrolytic activity of the immobilized whole-cell lipase was 30.77% higher than the activity obtained from free biomass (based on 1mg dry cell weight). Response surface methodology with a central composite design...
Source: Journal of Molecular Catalysis B: Enzymatic - December 13, 2016 Category: Biochemistry Source Type: research

Isolation of Pseudomonas granadensis B6 with (+)- γ-lactamase and whole cell resolution of racemic γ-lactam
Publication date: Available online 13 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Jinchang Wang, Dunfu Cheng, Jianjun Wang, Liang Jin We have isolated a strain that can produce (+)-γ-lactamase to hydrolyze racemic (+/−)-γ-lactam from several soil samples using (+/−)-γ-lactam as the only carbon source. We have identified this strain to be Pseudomonas granadensis B6. We further optimized the enzyme fermentation and biotransformation conditions for the γ-lactamase from P. granadensis B6. We found that glucose was the optimum carbon source and ammonium oxalate the optimum nitrogen ...
Source: Journal of Molecular Catalysis B: Enzymatic - December 13, 2016 Category: Biochemistry Source Type: research

Double mutations enhance β-cyclization activity of cyclodextrin glycosyltransferase from Bacillus circulans
Publication date: Available online 14 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Min Huang, Junyan Ren, Caiming Li, Zhengbiao Gu, Yan Hong, Li Cheng, Zhaofeng Li A major drawback to the industrial production of β-cyclodextrin is the limited β-cyclization activity of cyclodextrin glycosyltransferase (CGTase). Here, we construct mutants of the β-CGTase from Bacillus circulans strain STB01 that contain single substitutions at Tyr89 and double substitutions at Tyr89 and Asp577. The results show that the double mutants Y89G/D577R, Y89D/D577R, and Y89N/D577R display enhanced β-cycliz...
Source: Journal of Molecular Catalysis B: Enzymatic - December 13, 2016 Category: Biochemistry Source Type: research

Dextransucrase immobilized on activated-chitosan particles as a novel biocatalyst
Publication date: Available online 14 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Natália G. Graebin, Diandra de Andrades, Marina C. Bonin, Rafael C. Rodrigues, Marco A.Z. Ayub Dextransucrase from Leuconostoc mesenteroides B-512F was covalently immobilized on glutaraldehyde-actived chitosan particles. The best initial protein loading (400mg/g of dried support) showed 197U/g of catalytic activity. The optimal reaction pH and temperature of this new biocatalyst were determined to be 4.5 and 20°C, respectively. Regarding the thermal stability, the immobilization enhanced enzyme protect...
Source: Journal of Molecular Catalysis B: Enzymatic - December 13, 2016 Category: Biochemistry Source Type: research

Lipase immobilized on rosin-based functional polymers as a biocatalyst for the synthesis of ethyl dodecanoate
Publication date: Available online 12 December 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Pengfei Li, Ting Wang, Fuhou Lei, Qian Zeng, Hao Li, Jianxin Jiang Rosin is a renewable, solid, resinous material that has been widely used because of its excellent performance and availability. In this work, we synthesized two rosin-based functional polymers (PFME and PMMEag) bearing aldehyde groups by suspension polymerization, with ethylene glycol maleic rosinate acrylate (EGMRA) as a cross-linker, for the immobilization of porcine pancreas lipase. The effects of immobilization conditions, temperatur...
Source: Journal of Molecular Catalysis B: Enzymatic - December 12, 2016 Category: Biochemistry Source Type: research

Enzymes in the p-hydroxyphenylacetate degradation pathway of Acinetobacter baumannii
In this report, the HPA degradation operon in A. baumannii TH was investigated using genome walking and PCR amplification to identify the genes encoded by the operon. The results showed that there are thirteen ORFs that are involved in this process and their arrangement in the operon of A. baumannii TH is different from that in the operons of other previously reported species. ORFs 8-12 show clear variation compared to orthologous genes from other species, particularly at ORF9 which encodes for succinic semialdehyde dehydrogenase (SSADH) that is absent in other species. The ssadh gene was overexpressed and the results conf...
Source: Journal of Molecular Catalysis B: Enzymatic - December 10, 2016 Category: Biochemistry Source Type: research

Application of NAD(P)H oxidase for cofactor regeneration in dehydrogenase catalyzed oxidations
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part B Author(s): Gustav Rehn, Asbjørn Toftgaard Pedersen, John M. Woodley Biocatalytic oxidations can offer clear advantages compared to chemically catalyzed oxidations in terms of chemo, regio and stereoselectivity as well as a reduced environmental impact. One of the most industrially important reactions is the oxidation of alcohols, which can be carried out using alcohol dehydrogenases. However, their effective use requires an effective regeneration of the oxidized nicotinamide cofactor (NAD(P)+), which is critical for...
Source: Journal of Molecular Catalysis B: Enzymatic - December 10, 2016 Category: Biochemistry Source Type: research

Special issue OxiZymes 2016
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part B Author(s): Willem van Berkel, Marco Fraaije, Frank Hollmann (Source: Journal of Molecular Catalysis B: Enzymatic)
Source: Journal of Molecular Catalysis B: Enzymatic - December 10, 2016 Category: Biochemistry Source Type: research

A comparative study of papain and bromelain in enzymatic oligomerization of L-Phe methyl ester in aqueous environment
In this study, we developed an efficient approach for hydrophobic amino acids polymerization in aqueous solution. We compared the catalysis efficiency of papain and bromelain in catalyzing L-phenylalanine methyl ester (L-Phe-Me) for oligomer peptides synthesis. A set of reaction conditions (such as protease type, reaction temperature, time, and pH) have been tested for the polymerization reaction with papain and bromelain, respectively. Moreover, the resultant oligomers were analyzed through 1HNMR and MALDI-TOF. The results indicated that the average degree of polymerization (DP) reached the highest value (6.74) when papai...
Source: Journal of Molecular Catalysis B: Enzymatic - December 4, 2016 Category: Biochemistry Source Type: research

Investigation on the underlying mechanism: How fusion xylanase-ELPs self-assembles into insoluble active aggregates
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part A Author(s): Shuyu Wu, Yilin Wang, Tingting Shen, Junhui Wang, Guangya Zhang We have successfully obtained a recombinant xylanase by fusing with elastin-like polypeptides (ELPs), the xylanase SoxB underwent a sharp irreversible phase transition, and self-assembled into an insoluble but more catalytically operative particle. This was analogous to the immobilized xylanase to a large extent and aroused our interest to gain new insights into the determinant factor that may cause this phenomenon. We herein listed several ...
Source: Journal of Molecular Catalysis B: Enzymatic - December 2, 2016 Category: Biochemistry Source Type: research

Exploring the catalase activity of unspecific peroxygenases and the mechanism of peroxide-dependent heme destruction
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part A Author(s): Alexander Karich, Katrin Scheibner, René Ullrich, Martin Hofrichter The catalase activity of three unspecific peroxygenases (UPOs) from the agaric basidiomycetes Agrocybe aegerita, Coprinopsis cinerea and Marasmius rotula was investigated. The study included analysis of pH dependency of the catalase reaction and H2O2 mediated enzyme inactivation as well as experiments on the influence of a second substrate on the course of catalase reaction. Apparent kinetic parameters (Km, kcat) for the catalase activit...
Source: Journal of Molecular Catalysis B: Enzymatic - December 2, 2016 Category: Biochemistry Source Type: research