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.

Peroxidase activity enhancement of myoglobin by two cooperative distal histidines and a channel to the heme pocket
Publication date: Available online 15 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Lei-Bin Wu, Ke-Jie Du, Chang-Ming Nie, Shu-Qin Gao, Ge-Bo Wen, Xiangshi Tan, Ying-Wu Lina To reveal the structure-function relationship of heme proteins, and to provide clues for creating artificial heme proteins with improved functions, we here use myoglobin (Mb) as a model protein, and report that its peroxidase activity can be enhanced by construction of two distal histidines and a channel to the heme pocket. It showed that in addition to a single distal histidine with a suitable distance to the heme...
Source: Journal of Molecular Catalysis B: Enzymatic - October 15, 2016 Category: Biochemistry Source Type: research

Immobilization of Lipase on Mesoporous Silica Nanoparticles with Hierarchical Fibrous Pore
Publication date: Available online 13 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Zafar Ali, Lei Tian, Panpan Zhao, Baoliang Zhang, Nisar Ali, Mohammad Khan, Qiuyu Zhang Lipase from Candida Ragusa (CRL) was successfully covalently immobilized on fibrous silica nanoparticles KCC-1, and the properties of immobilized enzyme were investigated. Mesoporous fibrous silica nanoparticles (MSNPs) were synthesized with particles size 200nm pore size 15–30nm; followed by amino-functionalization. Scanning Electron Microscopy (SEM), transmittance electronic microscopy (TEM), Fourier Transform In...
Source: Journal of Molecular Catalysis B: Enzymatic - October 14, 2016 Category: Biochemistry Source Type: research

Characterization of a thermostable mannitol dehydrogenase from hyperthermophilic Thermotoga neapolitana DSM 4359 with potential application in mannitol production
Publication date: Available online 11 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Marwa Yagoub Farag Koko, Hinawi Abdo Mustafa Hassanin, Rebaone Letsididi, Tao Zhang, Wanmeng Mu Mannitol-2-dehydrogenase (MtDH) (E.C. 1.1.1.67) gene was cloned from Thermotoga neapolitana DSM 4359 and expressed in Escherichia coli BL21. The purified enzyme showed a predicted clear band of 36kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). K m and V max values for reduction of D-fructose to D-mannitol were 20mM and 200U mg-1 respectively. k cat for reduction direction was 180sâˆ...
Source: Journal of Molecular Catalysis B: Enzymatic - October 11, 2016 Category: Biochemistry Source Type: research

Nearly Aqueous-like Activity of Lipoprotein Lipase Treated with Glucose-Headed Surfactant in Organic Solvent
Publication date: Available online 11 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Yeonock Oh, Yoon Kyung Choi, Inyeol Yun, Eungyeong Lee, Kyungwoo Kim, Mahn-Joo Kim In this work, we explored the activation of a lipoprotein lipase from Burkholderia species by glucose-headed surfactants (GHSs) for enhancing its catalytic activity in organic solvent. Three GHSs were prepared and then tested as the additives for inducing the activation of lipoprotein lipase. The kinetic parameters of GHS-treated lipoprotein lipase were determined for the hydrolysis or alcoholysis of p-nitrophenyl acetate....
Source: Journal of Molecular Catalysis B: Enzymatic - October 11, 2016 Category: Biochemistry Source Type: research

Studies of carbon monoxide dehydrogenase from Oligotropha carboxidovorans
Publication date: Available online 11 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Stephanie Dingwall, Jarett Wilcoxen, Dimitri Niks, Russ Hille We have undertaken physicochemical studies of the CO dehydrogenase from the aerobe Oligotropha carboxidovorans, probing both the binuclear Mo- and Cu-containing active site where CO is oxidized to CO2 and the enzyme’s FAD, where the reducing equivalents obtained from CO are transferred to the quinone pool. Regarding the FAD site, we have characterized the semiquinone oxidation state by EPR and identified it to be of the blue neutral form with ...
Source: Journal of Molecular Catalysis B: Enzymatic - October 11, 2016 Category: Biochemistry Source Type: research

Efficient production of 5-aminovalerate from l-lysine by engineered Escherichia coli whole-cell biocatalysts
In this study, we developed a whole-cell biocatalysis process for high-level conversion of L-lysine into 5-aminovalerate. To obtain the highly efficient whole-cell biocatalyst, five expression plasmids were constructed to optimize the expression of 5-aminovaleramide amidohydrolase and L-lysine 2-monooxygenase in Escherichia coli. The engineered strain BL-22A-RB-YB harboring plasmid pET22b-davA, pRSFDuet-davB and pACYCDuet-davB was correspondingly obtained. Subsequently, the effects of induction conditions, reaction temperature, metal ion additives, and cell permeability on the whole-cell biocatalyst system were evaluated t...
Source: Journal of Molecular Catalysis B: Enzymatic - October 9, 2016 Category: Biochemistry Source Type: research

Purification and characterization of a fibrinolytic enzyme from the food-grade fungus, Neurospora sitophila
Publication date: Available online 8 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Xiao lan Liu, Narasimha kumar Kopparapu, Hong chen Zheng, Priti Katrolia, Yong ping Deng, Xi qun Zheng A fibrinolytic protease was purified from the culture supernatant of a GRAS fungus, Neurospora sitophila. The enzyme displayed a molecular mass of 34kDa, as estimated by SDS-PAGE and gel filtration chromatography. The isoelectric point (pI) of the enzyme was 9.3±0.2 as determined by iso-electric focusing (IEF). It was maximally active at pH 7.6 and 41°C and displayed remarkable stability in a wide pH r...
Source: Journal of Molecular Catalysis B: Enzymatic - October 9, 2016 Category: Biochemistry Source Type: research

The Two-Step Synthesis of 1, 3-Oleoyl-2-Palmitoylglycerol by Candida sp. 99-125 lipase
This study has shown that the two-step method could give a higher yield of OPO than the previously reported one-step method using economical lipase. Graphical abstract (Source: Journal of Molecular Catalysis B: Enzymatic)
Source: Journal of Molecular Catalysis B: Enzymatic - October 5, 2016 Category: Biochemistry Source Type: research

Evolved alkaline fungal laccase secreted by Saccharomyces cerevisiae as useful tool for the synthesis of C-N heteropolymeric dye
Publication date: Available online 4 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Ana I. Vicente, Javier Viña-Gonzalez, Paloma Santos-Moriano, Carlos Marquez-Alvarez, Antonio O. Ballesteros, Miguel Alcalde Enzymatic production of C-N heteropolymeric dyes at alkaline pHs is an attractive process for the textile industry. In this work, we have designed a fungal laccase by directed evolution so that it may be used at alkaline pHs for the synthesis of C-N heteropolymeric dyes (C-N polydye) from catechol and 2,5-diaminobenzenesulfonic acid (2,5-DABSA). Firstly, several medium- and high-red...
Source: Journal of Molecular Catalysis B: Enzymatic - October 4, 2016 Category: Biochemistry Source Type: research

Overexpression and characterization of CCD4 from Osmanthus fragrans and β-ionone biosynthesis from β-carotene in vitro
In this study, a recombinant carotenoid cleavage dioxygenase 4 was produced from Osmanthus fragrans by E .coli under different bacterial growth conditions and used to develop a biotechnological method for preparation of natural β-ionone from β-carotene. β-ionone was analyzed by HPLC and OfCCD4 activity was measured based on concentration change of β-ionone. At pH 8.0 and 35°C, the greatest activity of the purified recombinant protein was 14.3U/mg and the maximum concentration of β-ionone was 71.186mg/L within 1h. Both the enzyme activity and the concentration of β-ionone could increase by nearly 6 times with additio...
Source: Journal of Molecular Catalysis B: Enzymatic - October 4, 2016 Category: Biochemistry Source Type: research

Purification and characterization of an alkaline chloride-tolerant laccase from a halotolerant bacterium, Bacillus sp. strain WT
Publication date: Available online 4 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Maryam Siroosi, Mohammad Ali Amoozegar, Khosro Khajeh Laccases are multicopper oxidases with various biotechnological applications that oxidize different aromatic or inorganic substrates. In present work, different bacterial strains isolated from Urmia lake, a hypersaline lake in northwest of Iran, were screened to find laccase-producing ones. Spore and an extracellular enzyme from a halotolerant spore-forming bacterium, Bacillus sp. strain WT, showed laccase activity toward typical laccase substrates: syrin...
Source: Journal of Molecular Catalysis B: Enzymatic - October 4, 2016 Category: Biochemistry Source Type: research

RHA-P: isolation, expression and characterization of a bacterial α-L-rhamnosidase from Novosphingobium sp. PP1Y.
Publication date: Available online 3 October 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Federica De Lise, Francesca Mensitieri, Vincenzo Tarallo, Nicola Ventimiglia, Roberto Vinciguerra, Annabella Tramice, Roberta Marchetti, Elio Pizzo, Eugenio Notomista, Valeria Cafaro, Antonio Molinaro, Leila Birolo, Alberto Di Donato, Viviana Izzo α-l-Rhamnosidases (α-RHAs) are a group of glycosyl hydrolases of biotechnological potential in industrial processes, which catalyze the hydrolysis of α-l-rhamnose terminal residues from several natural compounds. A novel α−RHA activity was identifi...
Source: Journal of Molecular Catalysis B: Enzymatic - October 3, 2016 Category: Biochemistry Source Type: research

In vivo cytotoxicity, molecular docking and study of yeast alcohol dehydrogenase on polycarbazole-titanium dioxide nanocomposite
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part A Author(s): Mohammad Shakir, Mohd. Shoeb Khan, Umair Baig, Md. Fazle Alam, Hina Younus, Mahboob Alam The present work deals with the synthesis of an electrically conductive polycarbazole-titanium dioxide (PCz/TiO2-6%) nanocomposite employing facile in-situ oxidative polymerization of carbazole monomer. In order to immobilize the yeast alcohol dehydrogenase (YADH) enzyme, the polymerization reaction was done in the presence of TiO2 (titanium dioxide). The pristine PCz and PCz/TiO2-6% nanocomposites were fully charac...
Source: Journal of Molecular Catalysis B: Enzymatic - October 3, 2016 Category: Biochemistry Source Type: research

Enantioselective acetylation of (R,S)-atenolol: The use of Candida rugosa lipases immobilized onto magnetic chitosan nanoparticles in enzyme-catalyzed biotransformation
Publication date: December 2016 Source:Journal of Molecular Catalysis B: Enzymatic, Volume 134, Part A Author(s): Adam Sikora, Dorota Chełminiak-Dudkiewicz, Tomasz Siódmiak, Agata Tarczykowska, Wiktor Dariusz Sroka, Marta Ziegler-Borowska, Michał Piotr Marszałł This paper describes the enzyme immobilization protocol as well as the enzymatic method for the direct resolution of (R,S)-atenolol. The used magnetic enzyme carriers possess on their surface new-synthetized chitosan derivatives with free amine groups distanced by ethyl or butyl chain. Additionally the catalytic activity of two types of commercially av...
Source: Journal of Molecular Catalysis B: Enzymatic - September 22, 2016 Category: Biochemistry Source Type: research

Activity of enzymes immobilized on plasma treated polyester
Publication date: Available online 18 September 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Arfaoui Mohamed, Behary Nemeshwaree, Mutel Brigitte, Perwuelz Anne, Belhacene Kalim, Dhulster Pascal, Mamede Anne-Sophie, Froidevaux Rénato The aim of this study was to investigate the effect of 3 different surface plasma treatments on the immobilization of β-galactosidase on a fibrous PET nonwoven membrane. Two methods 1. Entrapment in a thin calcium alginate coating and 2. Direct sorption, were used to immobilize the enzyme. The three different plasma treatments for surface activation of PET nonw...
Source: Journal of Molecular Catalysis B: Enzymatic - September 18, 2016 Category: Biochemistry Source Type: research