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Laccase coli

Selin Ece, Camilla Lambertz, Rainer Fischer, Ulrich Commandeur
Laccases are used for the conversion of biomass into fermentable sugars but it is difficult to produce high yields of active laccases in heterologous expression systems. We overcame this challenge by expressing Streptomyces cyaneus CECT 3335 laccase in Escherichia coli (ScLac) and we achieved a yield of up to 104 mg L(-1) following purification by one-step affinity chromatography. Stability and activity assays using simple lignin model substrates showed that the purified enzyme preparation was active over a broad pH range and at high temperatures, suggesting it would be suitable for biomass degradation...
December 2017: AMB Express
Thamir H Al-Kahem Al-Balawi, Adam L Wood, Alexis Solis, Ted Cooper, Ravi D Barabote
We describe the isolation and characteristics of a novel thermophilic bacterium from soil. The organism is a member of the Anoxybacillus genus based on phylogenetic analysis of the 16S rRNA gene. The 16S rRNA of the organism shares >99% sequence identity with those of two species, Anoxybacillus rupiensis and A. geothermalis. We named this isolate as Anoxybacillus sp. strain UARK-01. UARK-01 grows optimally in the presence of oxygen at 55 °C and pH 8. It grew excellently in the presence of lignin as the sole carbon source...
April 8, 2017: Current Microbiology
Weichuan Qiao, Jingping Chu, Shaojun Ding, Xin Song, Lei Yu
In this work, a novel bacterial strain exhibiting laccase activity was isolated from black liquor and identified as Bacillus subtilis cjp3. The CotA-laccase gene was cloned from strain cjp3 and expressed in Escherichia coli. The purified recombinant laccase has a maximum activity of 7320 U/L, maintaining high stabilities under a wide pH range and high temperature conditions. Nearly no loss of laccase activity was observed even at pH 9.0 after 10 h of incubation. Reactive blue 19, reactive black 5 and indigo carmine could be efficiently decolorized by the purified laccase in the presence of a mediator ABTS...
March 30, 2017: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Saadia Basheer, Naeem Rashid, Raza Ashraf, Muhammad Sohail Akram, Masood Ahmed Siddiqui, Tadayuki Imanaka, Muhammad Akhtar
Genome search of Geobacillus thermopakistaniensis, formerly Geobacillus sp. SBS-4S, revealed the presence of an open reading frame (ESU71923) annotated as laccase. However, the gene product did not display any laccase-like activity against the substrates examined. The laccase activity was, therefore, purified from G. thermopakistaniensis cells and N-terminal amino acid residues of the enzyme were determined. These residues matched the N-terminal sequence of an open reading frame annotated as a copper oxidase (ESU72270)...
March 17, 2017: Extremophiles: Life Under Extreme Conditions
Kai Sun, Qingguo Huang, Shunyao Li
Enzyme-based catalyzed oxidative coupling reactions (E-COCRs) are considered as viable technologies to transform a variety of pharmaceutical antibiotics. This study indicated that the extracellular fungal laccase from Pleurotus ostreatus was effective in transforming tetracycline (TC) with 1-hydroxybenzotriazole (HBT) present at varying conditions during E-COCRs. The presence of humic acid (HA) showed suppressive effect on the transformation rate constants (k) of TC, and the k values for TC decreased as HA concentration increased...
March 1, 2017: Journal of Hazardous Materials
Pavlína Šlosarčíková, Čeněk Novotný, Kateřina Malachová, Hana Válková, Jindřich Fojtík
The aim was to investigate the effect of yeast organisms on the degradation process by immobilized cultures of ligninolytic fungi. Immobilization was accomplished by 7-day colonization of polyamide mesh with mycelial fragments. Irpex lacteus decolorized >90% of the initial concentration of 150mgl(-1) of anthraquinone Remazol Brilliant Blue R dye in three subsequent decolorization cycles and the degradation capacity was not negatively affected by the presence of 10(6)Saccharomyces cerevisiae cells per ml in the mixed culture...
March 1, 2017: Science of the Total Environment
Qingquan Liu, Le Luo, Xiaoxiao Wang, Zhenguo Shen, Luqing Zheng
Laccases are encoded by a multigene family and widely distributed in plant genomes where they play roles oxidizing monolignols to produce higher-order lignin involved in plant development and stress responses. We identified 30 laccase genes (OsLACs) from rice, which can be divided into five subfamilies, mostly expressed during early development of the endosperm, growing roots, and stems. OsLACs can be induced by hormones, salt, drought, and heavy metals stresses. The expression level of OsLAC10 increased 1200-fold after treatment with 20 μM Cu for 12 h...
January 30, 2017: International Journal of Molecular Sciences
Nobutada Kimura, Yoichi Kamagata
A gene coding for a multicopper oxidase (BopA) was identified through the screening of a metagenomic library constructed from wastewater treatment activated sludge. The recombinant BopA protein produced in Escherichia coli exhibited oxidation activity toward 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) in the presence of copper, suggesting that BopA is laccase. A bioinformatic analysis of the bopA gene sequence indicated that it has a phylogenetically bacterial origin, possibly derived from a bacterium within the phylum Deinococcus-Thermus...
December 23, 2016: Microbes and Environments
Sandeep Kumar, Kavish Kr Jain, Shikha Rani, Kailash N Bhardwaj, Manisha Goel, Ramesh Chander Kuhad
Among lignocellulolytic enzymes, laccases are the most versatile, broadly specific, and largely studied enzyme with a wide range of biotechnological potential. Putative laccase (CotA) from Bacillus pumilus MK001 was cloned and expressed in E. coli. In addition to soluble bioactive fraction, inactive inclusion body fraction was also harvested and refolded under optimized conditions resulting in 64 % of refolding efficiency. The enzyme was found to be thermostable exhibiting a half-life of 60 min at 80 °C...
December 2016: Molecular Biotechnology
Xiang Guo, Shan Zhou, Yanwei Wang, Jinlong Song, Huimin Wang, Delong Kong, Jie Zhu, Weiwei Dong, Mingxiong He, Guoquan Hu, Zhiyong Ruan
Laccases are green biocatalysts that possess attractive advantages for the treatment of resistant environmental pollutants and dye effluents. A putative laccase-like gene, laclK, encoding a protein of 29.3 kDa and belonging to the Cu-oxidase_4 superfamily, was cloned and overexpressed in Escherichia coli. The purified recombinant protein LaclK (LaclK) was able to oxidize typical laccase substrates such as 2,6-dimethoxyphenol and l-dopamine. The characteristic adsorption maximums of typical laccases at 330 nm and 610 nm were not detected for LaclK...
2016: PloS One
Tian-Nyu Wang, Min Zhao
Laccases are green oxidases with a number of potential industrial applications. In this study, recombinant Bacillus subtilis CotA laccase was secreted by Escherichia coli via both the α-hemolysin secretion system and the YebF secretion system after microaerobic induction. Meanwhile, we discovered a much simpler approach for extracellular production of recombinant CotA laccase from E. coli, involving alternation of induction conditions to release recombinant CotA following intracellular expression. By optimizing the induction parameters, the extracellular yield of recombinant CotA laccase was improved from 157...
January 2017: Applied Microbiology and Biotechnology
S L Mathews, C E Smithson, A M Grunden
AIMS: The aim of this study was to evaluate the activity of a novel bacterial laccase-like multi-copper oxidase (LMCO) from Paenibacillus glucanolyticus SLM1: a bacterium isolated from pulp and paper waste. METHODS AND RESULTS: A new bacterial LMCO gene (CuOx) from P. glucanolyticus SLM1 was identified and cloned into pET22b. The protein it encodes was recombinantly expressed in Escherichia coli. The recombinant P. glucanolyticus LMCO had a molecular weight of approximately 90 kDa and demonstrated oxidation of the LMCO substrates 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), catechol, and 2,6-Dimethoxyphenol (2,6-DMP), with the oxidation of ABTS occurring to the greatest extent (776 U mg(-1) under optimal conditions of pH 7 and 40°C)...
November 2016: Journal of Applied Microbiology
Xianghe Yuan, Guoting Tian, Yongchang Zhao, Liyan Zhao, Hexiang Wang, Tzi Bun Ng
Three laccase isoenzymes (Lac1, Lac2 and Lac3) have been purified to homogeneity from Pleurotus nebrodensis in our previous study. Lac2 was shown to be the dominant isoform, capable of oxidizing the majority of laccase substrates and manifesting good thermostability and pH stability. Hence, Lac2 was selected to decolourize structurally different dyes and the colour removal efficiencies of Lac2 and the crude extract of P. nebrodensis were compared. By monitoring the λmax of the reaction system during the course of biotransformation, clear hypsochromic shifts were observed for most of the dyes examined, illustrating that at least one peak disappeared as a result of laccase treatment...
August 2016: Bioscience Reports
Esther Ricklefs, Marco Girhard, Vlada B Urlacher
BACKGROUND: Pinoresinol is a high-value plant-derived lignan with multiple health supporting effects. Enantiomerically pure pinoresinol can be isolated from natural sources, but with low efficiency. Most chemical and biocatalytic approaches that have been described for the synthesis of pinoresinol furnish the racemic mixture. In this study we devised a three-step biocatalytic cascade for the production of enantiomerically pure pinoresinol from the cheap compound eugenol. Two consecutive oxidations of eugenol through vanillyl-alcohol oxidase and laccase are followed by kinetic resolution of racemic pinoresinol by enantiospecific pinoresinol reductases...
May 9, 2016: Microbial Cell Factories
Jizhong Wang, Chengli Yang, Xing Chen, Bingxin Bao, Xuan Zhang, Dali Li, Xingfan Du, Ruofu Shi, Junfang Yang, Ronghui Zhu
OBJECTIVES: To find an efficient and cheap system for NAD(+) regeneration RESULTS: A NADH-ferricyanide dehydrogenase was obtained from an isolate of Escherichia coli. Optimal activity of the NADH dehydrogenase was at 45 °C and pH 7.5, with a K m value for NADH of 10 μM. By combining the NADH dehydrogenase, potassium ferricyanide and laccase, a bi-enzyme system for NAD(+) regeneration was established. The system is attractive in that the O2 consumed by laccase is from air and the sole byproduct of the reaction is water...
August 2016: Biotechnology Letters
Sheng Yang, Yan Long, Hong Yan, Huawan Cai, Yadong Li, Xingguo Wang
The cumA, a gene encoding a multicopper oxidase (MCO), was cloned from the soil-dwelling bacterium Pseudomonas sp. 593. Its corresponding product was overexpressed in Escherichia coli BL21 (DE3) pLysS and purified to homogeneity through Ni-affinity chromatography. The amino acid sequence of the CumA of Pseudomonas sp. 593 was strongly homologous to that of CumA as previously reported. The CumA was quite stable in neutral pH and had poor thermostability. Meanwhile, its optimum pH and temperature toward laccase substrates 2,6-dimethoxyphenol (DMP), syringaldazine (SGZ), and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) were 5...
April 21, 2016: Biotechnology and Applied Biochemistry
Azam Safary, Rezvan Moniri, Maryam Hamzeh-Mivehroud, Siavoush Dastmalchi
An efficient method was introduced for soluble expression of recombinant laccase (rpCotA(SL-1)) from a newly isolated halo-thermotolerant Bacillus sp. SL-1 in modified Escherichia coli, trxB2/gor2 mutant (Origami™ B (DE3)). The yield of purified soluble laccase in Origami strain under micro-aerobic condition was ∼20mg/L of bacterial culture, showing significant improvement over the laccase produced in E.coli BL21 strain under aerobic condition. The specific activity of 13U/mg for purified laccase produced in micro-aerobic condition was higher than that of 1...
June 10, 2016: Journal of Biotechnology
Fabio Tonin, Elena Rosini, Luciano Piubelli, Antonio Sanchez-Amat, Loredano Pollegioni
Polyphenol oxidase from the marine bacterium Marinomonas mediterranea (MmPPOA) is a membrane-bound, blue, multi-copper laccase of 695 residues. It possesses peculiar properties that distinguish it from known laccases, such as a broad substrate specificity (common to tyrosinases) and a high redox potential. In order to push the biotechnological application of this laccase, the full-length enzyme was overexpressed in Escherichia coli cells with and without a C-terminal His-tag. The previous form, named rMmPPOA-695-His, was purified to homogeneity by HiTrap chelating chromatography following solubilization by 1% SDS in the lysis buffer with an overall yield of ≈1 mg/L fermentation broth and a specific activity of 1...
July 2016: Protein Expression and Purification
Morteza Shojaei Moghadam, Andreas Albersmeier, Anika Winkler, Lorenzo Cimmino, Kjersti Rise, Martin Frank Hohmann-Marriott, Jörn Kalinowski, Christian Rückert, Alexander Wentzel, Rahmi Lale
BACKGROUND: Marine cold-temperature environments are an invaluable source of psychrophilic microbial life for new biodiscoveries. An Arctic marine bacterial strain collection was established consisting of 1448 individual isolates originating from biota, water and sediment samples taken at a various depth in the Barents Sea, North of mainland Norway, with an all year round seawater temperature of 4 °C. The entire collection was subjected to high-throughput screening for detection of extracellular laccase activity with guaiacol as a substrate...
February 16, 2016: BMC Genomics
Laura Sevillano, Erik Vijgenboom, Gilles P van Wezel, Margarita Díaz, Ramón I Santamaría
BACKGROUND: Actinomycetes are saprophytic soil bacteria, and a rich source of industrial enzymes. While some of these enzymes can be produced using well-characterized production platforms such as Escherichia coli or Bacillus subtilis, Streptomyces lividans may be the preferred host for proper folding and efficient secretion of active enzymes. A combination of promoters, signal peptides and hosts were tested in order to obtain the best protein expression in this actinomycete. The xylanase, Xys1, from S...
2016: Microbial Cell Factories
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