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Anne Elisabeth E Berns, Herbert Philipp, Hans Lewandowski, Jeong-Heui Choi, Marc Lamshöft, Hans-Dieter Narres
The extensive use of sulfonamides (SNs) in animal husbandry has led to an unintentional widespread occurrence in several environmental compartments. The implementation of regulations and management recommendations to reduce the potential risk of development of antibiotic resistances necessitates detailed knowledge on their fate in soil. We present results from two independent incubation studies of15 N-labeled sulfadiazines (SDZ) which focused on identifying binding types in bound residues. In the first study15 N-amino labeled SDZ was incubated with two previously isolated humic acids in the presence and absence of Trametes versicolor laccase, while in the second study15 N-double-labeled SDZ was incubated with a typical agricultural Luvisol and isolated the humic acid fraction after sequential extraction of the soil...
February 21, 2018: Environmental Science & Technology
Suse Botelho da Silva, Malgorzata Krolicka, Lambertus A M van den Broek, August E Frissen, Carmen Gabriela Boeriu
Chitosan is a polysaccharide with recognized antioxidant, antimicrobial and wound healing activities. However, this polymer is soluble only in dilute acidic solutions, which restricts much of its applications. A usual strategy for improving the functionality of polysaccharides is the selective oxidation mediated by 2,2,6,6-tetra-methyl-1-piperidinidyloxy (TEMPO) using laccase as a co-oxidant. In this work, the TEMPO-laccase redox system was used for the first time to selectively oxidize chitosan in order to produce tailored derivatives...
April 15, 2018: Carbohydrate Polymers
J A Chicatto, K T Rainert, M J Gonçalves, C V Helm, D Altmajer-Vaz, L B B Tavares
In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF) system. SSF assays were conducted with peach-palm (Bactris gasipaes) residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G...
February 15, 2018: Brazilian Journal of Biology, Revista Brasleira de Biologia
Raj Kumar Pandey, Khan Chand, Lakshmi Tewari
BACKGROUND: Lignocellulosic biomass from bamboo appears as an attractive feedstock for bioethanol industry due to its high cellulosic content and fast growth rate. Therefore, powdery biomass was first enzymatically delignified and then saccharified using crude enzymes. RESULTS: The biological pretreatement decreased the lignin content of the biomass from an initial value of 29.5 to 8.4% with a simultaneous increase in exposed cellulose content from 37.93% to 61...
February 13, 2018: Journal of the Science of Food and Agriculture
Ji Eun Song, Jing Su, Jennifer Noro, Artur Cavaco-Paulo, Carla Silva, Hye Rim Kim
In this work a process for the bio-coloration of bacterial cellulose (BC) membranes was developed. Laccase from Myceliophthora thermophila was immobilized onto BC membranes and retained up to 88% of residual activity after immobilization. Four compounds belonging to the flavonoids family were chosen to test the in situ polymerase activity of immobilized laccase. All the flavonoids were successfully polymerized by laccase giving rise to yellow, orange and dark brown oligomers which conferred color to the BC support...
February 13, 2018: AMB Express
Qiang Wang, Yanrong Ren, Yangping Ding, Minwei Xu, Bingcan Chen
The incorporation of bioactive proteins and peptides into food is associated with the loss of bioactivity due to deactivation in complex food matrices and in digestion systems. In this study, two different types of protein carriers, i.e. biopolymer complexation and complex coacervation were fabricated using whey protein isolation (WPI, 6wt%) and beet pectin (BP, 1.25 and 1.00wt%) at pH5.5 and 3.5, respectively. The release of the encapsulated FITC-BSA, a model bioactive protein, in both carriers in the absence and presence of laccase was investigated at both pH7...
March 2018: Food Research International
Cong Chao, Huijuan Guan, Jun Zhang, Yang Liu, Yafei Zhao, Bing Zhang
Laccase was immobilized in polyvinyl alcohol beads containing halloysite nanotubes (PVA/HNTs) to improve the stability and reusability of enzyme. The porous structure of PVA/HNTs beads facilitates the entrapment of enzyme and prevents the leaching of immobilized laccase as well. Halloysite nanotubes act as bridge to connect the adjacent pores, facilitating the electron transfer and enhancing the mechanical properties. PVA/HNTs beads have high laccase immobilization capacity (237.02 mg/g) and activity recovery yield (79...
February 2018: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Roelant Hilgers, Jean-Paul Vincken, Harry Gruppen, Mirjam A Kabel
Laccase-mediator systems (LMS) have been widely studied for their capacity to oxidize the nonphenolic subunits of lignin (70-90% of the polymer). The phenolic subunits (10-30% of the polymer), which can also be oxidized without mediators, have received considerably less attention. Consequently, it remains unclear to what extent the presence of a mediator influences the reactions of the phenolic subunits of lignin. To get more insight in this, UHPLC-MS was used to study the reactions of a phenolic lignin dimer (GBG), initiated by a laccase from Trametes versicolor, alone or in combination with the mediators HBT and ABTS...
February 5, 2018: ACS Sustainable Chemistry & Engineering
Marine Breitwieser, Hélène Thomas-Guyon, Valérie Huet, Kjetil Sagerup, Perrine Geraudie
This work was designed to investigate biological impacts on blue mussels (Mytilus edulis spp) after being exposed to diesel spill. On December 2013, an 180,000-litre accidental acute diesel spill was reported in a small harbour of northern Norway (Skjervøy). In order to assess the biological effects on the wild population of blue mussels, bivalves were collected at three different locations: at the oil-spill spot, at the other side of the harbour (opposite the oil-spill area), and in an uncontaminated site...
February 7, 2018: Ecotoxicology and Environmental Safety
Krishna Kant Sharma, Deepti Singh, Surender Rawat
Laccase in Cryptococcus neoformans is covalently linked to the carbohydrate moiety of the cell wall, which allows it to get access to the different substrates for catalyzing their oxidation and therefore plays a vital role in the virulence. The laccase gene (3.0 kb) from C. neoformans serotype D was amplified, cloned and sequenced for protein modeling, docking and simulation studies. The three dimensional homology models of laccase protein from C. neoformans and other pathogenic gut bacteria were docked with selected biomolecules like prostaglandins (PG), membrane phospholipids, neurotransmitters (serotonin) using GOLD software...
February 3, 2018: Computational Biology and Chemistry
Atefeh Khodakarami, Negar Goodarzi, Mahshid Hoseinzadeh, Fezzeh Amani, Shima Khodaverdian, Khosro Khajeh, Farideh Ghazi, Bijan Ranjbar, Masoud Amanlou, Bahareh Dabirmanesh
Laccases are multicopper oxidases that catalyze the oxidation of variety of substrates. The specificity and efficiency of laccases are clearly the important components leading to their remarkable uses. To develop an improved biocatalysts, site directed mutagenesis of laccase from Bacillus HR03 was carried out in the current study. Based on the ABTS-bound crystal structure of CotA from B. subtilis and alignment with closely related enzymes, T415 and T418 at the vicinity of the type 1 copper site were chosen and several mutants (T415I, T418I, T415G, T415G/T418I) were made...
February 6, 2018: International Journal of Biological Macromolecules
Daily Rodríguez-Padrón, Alain R Puente-Santiago, Alvaro Caballero, Alina M Balu, Antonio A Romero, Rafael Luque
A biocatalytic system based on laccase functionalized waste-derived iron oxide nanoparticles (LAC-DA-Fe2O3) was designed by a mechanochemical approach and employed in the electrocatalytic reduction of oxygen. Full characterization of the obtained bioconjugates revealed that the protein adopted a partially unfolded state. The mentioned configuration, together with the geometry coordination changes along the T1 center can be further related to a high bioelectrocatalytic response. A current density up to 2.9 mA cm-2 has been achieved, which is among the highest values reported in literature for laccase functionalized nanomaterials...
February 9, 2018: Nanoscale
Zhi-Hua Liu, Shangxian Xie, Furong Lin, Mingjie Jin, Joshua S Yuan
Background: Lignin valorization has recently been considered to be an essential process for sustainable and cost-effective biorefineries. Lignin represents a potential new feedstock for value-added products. Oleaginous bacteria such as Rhodococcus opacus can produce intracellular lipids from biodegradation of aromatic substrates. These lipids can be used for biofuel production, which can potentially replace petroleum-derived chemicals. However, the low reactivity of lignin produced from pretreatment and the underdeveloped fermentation technology hindered lignin bioconversion to lipids...
2018: Biotechnology for Biofuels
Zhen Zhang, Jin Liu, Jin Fan, Zhiyong Wang, Lin Li
In this study, we report an electrochemical microbial biosensor that was made by immobilizing a bacterial laccase on the surface of Escherichia coli cells followed by adsorption of modified live cells onto a glassy-carbon electrode. Expression and surface localization of laccase on target cells were confirmed by Western blotting, flow cytometry assays and immunofluorescence microscopy observation. Increased tandem-aligned anchors with three repeats of the N-terminal domain of an ice nucleation protein were used to construct a highly active E...
June 7, 2018: Analytica Chimica Acta
Maija-Liisa Mattinen, Juan José Valle-Delgado, Timo Leskinen, Tuomas Anttila, Guillaume Riviere, Mika Sipponen, Arja Paananen, Kalle Lintinen, Mauri Kostiainen, Monika Österberg
Cross-linked and decolorized lignin nanoparticles (LNPs) were prepared enzymatically and chemically from softwood Kraft lignin. Colloidal lignin particles (CLPs, ca. 200 nm) in a non-malodorous aqueous dispersion could be dried and redispersed in tetrahydrofuran (THF) or in water retaining their stability i.e. spherical shape and size. Two fungal laccases, Trametes hirsuta (ThL) and Melanocarpus albomyces (MaL) were used in the cross-linking reactions. Reactivity of ThL and MaL on Lignoboost™ lignin and LNPs was confirmed by high performance size exclusion chromatography (HPSEC) and oxygen consumption measurements with simultaneous detection of red-brown color due to the formation of quinones...
April 2018: Enzyme and Microbial Technology
Alexander V Lisov, Oksana V Belova, Nataliya G Vinokurova, Tatiana V Semashko, Anatolii G Lobanok, Alexey A Leontievsky
This work investigated the regulatory role of the interaction between cellobiose dehydrogenase (CDH) and β-glucosidase (β-GLU) in the conversion of cellobiose into cellobionolactone or glucose in vitro. To study the regulation, the two enzymes were isolated from the culture medium of the fungus Cerrena unicolor grown on a medium with microcrystalline cellulose. The enzymes were obtained in an electrophoretically homogeneous state. Their properties were studied. Both enzymes had acidic pH optima and were more stable in the acidic pH range...
February 8, 2018: Journal of Basic Microbiology
Wensong Jin, Jiahuan Li, Hongchang Feng, Si You, Liaoyuan Zhang, Justice Norvienyeku, Kaihui Hu, Shujing Sun, Zonghua Wang
In this study, a novel laccase gene (Lcc1) from Ganoderma tsugae was isolated and its functions were characterized in detail. The results showed that Lcc1 has the highest expression activity during mycelium development and fruit body maturation based on the analysis of Lcc1 RNA transcripts at different developmental stages of G. tsugae. To investigate the exact contribution of Lcc1 to mycelium and fruit body development in G. tsugae, Lcc1 transgenic strains were constructed by targeted gene replacement and over-expression approaches...
February 6, 2018: International Journal of Molecular Sciences
Miranda J Meents, Yoichiro Watanabe, A Lacey Samuels
Background: Secondary cell walls (SCWs) form the architecture of terrestrial plant biomass. They reinforce tracheary elements and strengthen fibres to permit upright growth and the formation of forest canopies. The cells that synthesize a strong, thick SCW around their protoplast must undergo a dramatic commitment to cellulose, hemicellulose and lignin production. Scope: This review puts SCW biosynthesis in a cellular context, with the aim of integrating molecular biology and biochemistry with plant cell biology...
February 5, 2018: Annals of Botany
Na Liu, Shuzhen Ni, Arthur J Ragauskas, Xianzhi Meng, Naijia Hao, Yingjuan Fu
An effective method to functionalize chitosan with 4-hexyloxyphenol (HP) under homogeneous reaction conditions was developed using laccase as the catalyst. The resulting copolymer was characterized for chemical structure, grafted-HP content, surface morphology, thermal stability, antioxidant capacity, hydrophobic properties and tensile strength. Solid-state 13C NMR spectrum confirmed the incorporation of HP onto chitosan. X-ray diffraction (XRD) showed a decrease in the degree of crystallinity for laccase/HP treated chitosan compared to pure chitosan...
January 30, 2018: Journal of Biotechnology
Hu Jinyuan, Kun Lu, Shipeng Dong, Qingguo Huang, Liang Mao
Laccase is a multicopper oxidase that contains four coppers, including one type 1, one type 2, and two type 3. We here provide the first experimental data showing that As (III) can be effectively removed from water and transformed to As (V) through reactions mediated by laccase with the presence of oxygen. To this end, the As (III) removal, As (V) yields, total protein, active laccase, and copper concentrations in the aqueous phase were determined, respectively. Additionally, electron paramagnetic resonance (EPR) spectra and UV-vis spectra were applied to probe possible structural changes of the laccase during the reaction...
February 6, 2018: Environmental Science & Technology
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