Journal of Molecular Catalysis B: Enzymatic This 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.

Microbial hydroxylation of steroids by Penicillium decumbens
Publication date: Available online 16 February 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Shuhong Mao, Lixia Zhang, Zhijiang Ge, Xuerong Wang, Yanqing Li, Xiaoguang Liu, Fei Liu, Fuping Lu Biotransformation of steroid compounds: androst-4-ene-3, 17-dione (1), 19-nor-4-androstene-3, 17-dione (2), 13β-ethyl-4-gonene-3, 17-dione (3) using Penicillium decumbens as biocatalyst was investigated, and selective hydroxylation of 1, 2 and 3 was observed. Biotransformation of 1 afforded 1α-hydroxy −androst-4-ene-3, 17-dione (4) and 1α, 6β-dihydroxy-androst-4-ene-3, 17-dione (5). Incubation of 1...
Source: Journal of Molecular Catalysis B: Enzymatic - February 16, 2017 Category: Biochemistry Source Type: research

Purification, Characterization and Gene Identification of a α-Neoagarooligosaccharide Hydrolase from an Alkaliphilic Bacterium Cellvibrio sp. WU-0601
Publication date: Available online 14 February 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Teruhiko Watanabe, Kana Kashimura, Kohtaro Kirimura Purification, enzymatic characterization and gene identification of the neoagarooligosaccharide hydrolase (EC 3.2.1.159, α-NAOS hydrolase) intracellularly produced by agar-degrading Cellvibrio sp. WU-0601, an alkaliphilic bacterium isolated from soil, were performed. α-NAOS hydrolase activity was detected only in the cell-free extract, not but culture filtrate, and α-NAOS hydrolase was purified from the cell-free extract through four purification steps...
Source: Journal of Molecular Catalysis B: Enzymatic - February 14, 2017 Category: Biochemistry Source Type: research

Increasing the hydrolytic activity of lipase in oil/water two-phase system using surfactant –enzyme nanocomposite
In this study, a lipase/Na n Co m (DC) n +2m composite was successfully synthesized via the co-precipitation of Candida rugosa lipase (CRL), sodium deoxycholate (NaDC), and cobalt ions. Composite characterization confirmed that CRL was successfully embedded in Na n Co m (DC) n +2m , with particle diameters from 50nm to 120nm. Furthermore, the nanocomposite not only exhibited lipase hydrolytic activity but also showed surfactant function. As a result, the nanocomposite showed a 2.8-fold increase in hydrolytic activity as compared to the free CRL. In addition, the nanocomposite exhibited excellent adaptability over a wider t...
Source: Journal of Molecular Catalysis B: Enzymatic - February 8, 2017 Category: Biochemistry Source Type: research

Gene cloning and characterization of a psychrophilic phthalate esterase with organic solvent tolerance from an Arctic bacterium Sphingomonas glacialis PAMC 26605
In this study, we cloned a gene encoding the psychrophilic phthalate esterase (hereafter referred to as EstSP1) from an Arctic bacterium, Sphingomonas glacialis PAMC 26605, and characterized the properties of recombinant EstSP1 protein. EstSP1 belongs to the α/β hydrolase family and its catalytic triad consists of Ser 161, Asp 253, and His 283 residues. Thermal stability and protein folding of EstSP1 were reduced under ambient temperatures when compared with those at 4°C, despite EstSP1 maintaining its secondary structure at 4°C–50°C. EstSP1 is unique among cold-adapted esterases in that it not only has substrate pr...
Source: Journal of Molecular Catalysis B: Enzymatic - February 7, 2017 Category: Biochemistry Source Type: research

Near UV difference spectroscopy application for ferulic acid esterases substrate specificity determination
Publication date: Available online 6 February 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Gleb S. Dotsenko, Anna S. Dotsenko, Arkady P. Sinitsyn Ferulic acid esterases (FAEs) are promising enzymes for potential application in agricultural, food, paper, and pharmaceutical industries. Discovery and characterization of novel FAEs is still up to date. Depending on their substrate specificity towards four methyl hydroxycinnamates (methyl esters of ferulic, p-coumaric, caffeic, and sinapic acids), FAEs are classified into four subgroups, named A, B, C, and D types. In this work we investigate practica...
Source: Journal of Molecular Catalysis B: Enzymatic - February 6, 2017 Category: Biochemistry Source Type: research

An Unexpected Inversion of CAL-B Enantiopreference Based on Substrate Engineering of 2-Bromoesters: Effect of (R)-1-Phenylethyl moiety
Publication date: Available online 2 February 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Thiago Sabino da Silva, Suelem Kluconski Campos, Alfredo R.M. de Oliveira, Leandro Piovan Candida antarctica lipase B (CAL-B) is one of the most useful enzymes for preparation of optically active alcohols and amines. However, CAL-B substrate’s scope for enzymatic kinetic resolution (EKR) of carboxylic acids and their derivatives is limited, especially by low stereoselectivity. In an attempt to overcome this drawback, we decided to employ substrate engineering of enzymatic transesterification of 2-bromobu...
Source: Journal of Molecular Catalysis B: Enzymatic - February 1, 2017 Category: Biochemistry Source Type: research

Immobilization of Y. lipolytica lipase and the continuous synthesis of geranyl propionate
In this study, Y. lipolytica lipase LIP2 (Lip2) was immobilized on the macroporous adsorptive resin DA201-C in n-heptane and then used to catalyze the continuous synthesis of geranyl propionate in a continuous stirred tank reactor (CSTR). With the lipase loading of 0.01g/g resin, 25°C and adsorption for 3h, the immobilization efficiency can be up to 98.6% and the synthetic activity of the lipase was 690.8U/g after immobilization, representing an increase of 28.5% compared with the free lipase (synthetic activity 537.2U/g). The immobilized Lip2 was used to generate geranyl propionate in CSTR, the continuous production of g...
Source: Journal of Molecular Catalysis B: Enzymatic - January 29, 2017 Category: Biochemistry Source Type: research

Improved enantioselective esterification of DL-menthol catalyzed by immobilized TL 100L lipase
Publication date: Available online 29 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Jie Sun, Chao Ding, Jian-Yong Zheng, Xin-Jun Yu, Man Zhao, Zhao Wang Lipozyme TL IM exhibits high enantioselectivity for the resolution of DL-menthol by the esterification of L-menthol. However, in this study, some factors such as protein loss, enzyme inactivation, and acetaldehyde damage greatly reduced the reaction conversion. For relieving the effects of these factors, macroporous resin that absorbs more protein was selected to immobilize Lipozyme TL 100L lipase with trehalose as the modifying agent. ...
Source: Journal of Molecular Catalysis B: Enzymatic - January 28, 2017 Category: Biochemistry Source Type: research

A coupled system involving arginase and urease for L-ornithine production
Publication date: Available online 27 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Kai Huang, Tao Zhang, Bo Jiang, Wanmeng Mu, Ming Miao L-ornithine, a non-protein amino acid, is widely used as a food supplement and nutrition product that is usually produced by the enzymatic hydrolysis of L-arginine. However, urea, a by-product, complicates purification of L-ornithine. Here, we describe a highly efficient coupled system, which involves Rummeliibacillus pycnus arginase and Jack bean urease, for the production of L-ornithine without urea residue. Although R. pycnus arginase exhibited the ...
Source: Journal of Molecular Catalysis B: Enzymatic - January 27, 2017 Category: Biochemistry Source Type: research

Baker ’s yeasts driven synthesis of enantiomers of ethyl 1-hydroxy-1-(3,4-dimethoxyphenyl)methane(P-phenyl)phosphinate – possible organophosphorus CDA’s.
Publication date: Available online 25 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ewa Żymańczyk-Duda, Kinga Kozyra, Małgorzata Brzezińska-Rodak, Magdalena Klimek-Ochab Different forms of biocatalysts (baker’s yeasts) were applied for the kinetic resolution of ethyl ester of 1-hydroxy-1-(3,4-dimethoxyphenyl)-methane(P-phenyl)phosphinic acid via enantioselective oxidation of hydroxyl-functionality. Stereochemistry of the reaction was modulated by the bioconversion conditions (e.g. presence of defined chemical additives in the biotransformation medium) and by the use of different for...
Source: Journal of Molecular Catalysis B: Enzymatic - January 25, 2017 Category: Biochemistry Source Type: research

Sustainable enzymatic synthesis of glycolipids in a deep eutectic solvent system
In this study a reaction system based on a deep eutectic solvent consisting of choline chloride and various sugars, was used for the enzymatic synthesis of glycolipids. A wide variety of potential substrates were tested for the enzymatic glycolipid synthesis in DES, including various sugars and one anhydro-sugar in combination with up to 9 different fatty acids. It was proven that the described DES-based solvent system is suitable for the enzymatic synthesis of tailor-made glycolipids. The proposed lipase-catalyzed acylation of the different sugars, which are substrate and part of the solvent at the same time, was detected...
Source: Journal of Molecular Catalysis B: Enzymatic - January 24, 2017 Category: Biochemistry Source Type: research

Asymmetric synthesis of strongly fluorescent spirooxazino derivatives via multi-enzymatic telescopic reactions
Publication date: Available online 24 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Xiao-Yang Chen, Yu-Jing Hu, Tao Hu, Xian-Fu Lin, Qi Wu Herein we reported an unprecedented two-lipase-catalyzed telescopic reaction, combining PPL (lipase from porcin pancreas)-catalyzed asymmetric aldol reactions with CALB (lipase B from Candida antarctica)-catalyzed multi-component reactions (MCRs), for the asymmetric synthesis of complicated spirooxazino derivatives with strong fluorescence emission ability. Graphical abstract (Source: Journal of Molecular Catalysis B: Enzymatic)
Source: Journal of Molecular Catalysis B: Enzymatic - January 24, 2017 Category: Biochemistry Source Type: research

Gene Cloning, Expression, Immobilization and Characterization of Endo-xylanase from Geobacillus sp. TF16 and Investigation of Its Industrial Applications
Publication date: Available online 24 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ummuhan Cakmak, Nagihan Saglam Ertunga The xylanase gene (xynTF16) from a thermophilic bacterium Geobacillus sp. TF16 was cloned into pET-28a(+) vector and expressed in Escherichia coli BL21(DE3)pLysS. Recombinant enzyme (GsXynTF16) was purified 52-fold by nickel affinity chromatography, and determined as a single band 39.8kDa on SDS-PAGE with a specific activity of 246U/mg protein. The recombinant enzyme was immobilized on chitosan with a yield of 85.6%. The enzyme showed the highest activity towards xylan....
Source: Journal of Molecular Catalysis B: Enzymatic - January 24, 2017 Category: Biochemistry Source Type: research

Aspergillus flavipes Methionine γ-Lyase-Dextran Conjugates with Enhanced Structural, Proteolytic Stability and Anticancer Efficiency
Publication date: Available online 22 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ashraf S.A. El-Sayed, Abdalla E.A. Hassan, Ahmed A. Shindia, Shaimaa G. Mohamed, Mahmoud Z. Sitohy Aspergillus flavipes l-methionine γ-lyase (AfMGL) has been recognized as a powerful broad range anticancer agent. However, catalytic instability and antigenicity are the main challenges of its applications in vivo. Thus, the objective of this study was to investigate the influence of conjugation with dextran on AfMGL biochemical properties and functionality. The activity of dextran AfMGL conjugates was 50% ...
Source: Journal of Molecular Catalysis B: Enzymatic - January 23, 2017 Category: Biochemistry Source Type: research

Pyrroloquinoline Quinone-Dependent Glucose Dehydrogenase Anode: d-Galacturonic Acid Oxidation and Galactaric Acid Production
Publication date: Available online 23 January 2017 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Riku Sakuta, Kouta Takeda, Kiyohiko Igarashi, Hiroyuki Ohno, Nobuhumi Nakamura To replace fossil resources with biomass, a lot of conversion methods have been studied. Most of each biomass-conversion usually correspond to one specific purpose, such as to produce chemicals, fuels, or energy. However, when a production of chemicals is through one or more oxidation reactions, co-production of electricity is possible through a conversion on an enzymatic bioanode in a biofuel cell. The simultaneous production ...
Source: Journal of Molecular Catalysis B: Enzymatic - January 23, 2017 Category: Biochemistry Source Type: research