Screening, Production and Partial Characterization of a Thermostable Laccase from Trametes sp. Isolate B7 with Biotechnological Potentials

2019 ◽  
pp. 1-16
Author(s):  
Benjamin Vandelun Ado ◽  
Tivkaa Joseph Amande ◽  
Esther E. Ebah ◽  
Daniel Malo Mabitine
Keyword(s):  
Large Scale ◽  
Trichoderma Viride ◽  
Laccase Production ◽  
Synthetic Dyes ◽  
Phenol Red ◽  
Rhizopus Stolonifer ◽  
Optimum Stability ◽  
Wide Range ◽  
Large Scale Screening

The search for efficient and green oxidation technologies has increased interest in utilization of laccases in non conventional methods. Laccases catalyze a wide range of substrates due to low substrate specificity and strong oxidative potentials. Challenges to large-scale enzyme utilization include, low enzyme activity and instability which restrict use in many areas of biotechnology. In the study, 59 fungi comprising Aspergillus niger (40%), Trichoderma harzianum (31%), Aspergillus flavus (9.0%), Trichoderma viride (5.0%), Fusarium oxysporum (5.0%), Rhizopus stolonifer (5.0%), Trametes sp. (3.0%) and Aspergillus nidulans (2.0%) were isolated and screened for laccase production. Plate screening test showed 57.5%, 34.0% and 8.5% of fungi were laccase-positive on ABTS, Guaiacol, and α-naphthol agar respectively. Isolates were further screened in liquid cultures, and the highest laccase producer identified molecularly. Trametes sp isolate B7 was selected for solid state fermentation (SSF). Laccase production in SSF was highest at pH 5.0 (2356 U/mL). The purified laccase showed high activity (pH 3.0 - 6.0) and stability (pH 3.0 - 8.5) using ABTS. It was active (20 - 80°C) and thermostable (30 - 80°C) with optimum stability at 70°C (100% for 1 hour). The percentage decolourization of Phenol red were 28% and 36% using 1000 U/mL and 2000 U/mL crude laccases respectively. Similarly, RBBR (100%), Congo red (75%) and Malachite green (62%), and 77.4%, 64% and 28% were decolourized using 1000 U/mL and 2000 U/mL crude laccases respectively. ABTS agar was very reliable in large-scale screening for laccase which possessed thermostable property and degraded synthetic dyes without use of enzyme mediators. These attribute made the enzyme suitable for application in industry and biotechnology.

scholarly journals Production of Fungal Laccase under Solid State Bioprocessing of Agroindustrial Waste and Its Application in Decolourization of Synthetic Dyes

2019 ◽  
pp. 1-17
Author(s):  
Benjamin Vandelun Ado ◽  
Abiodun Anthony Onilude ◽  
Hyacinth Ocheigwu Apeh Oluma ◽  
Daniel Malo Mabitine
Keyword(s):  
Solid State ◽  
Large Scale ◽  
Specific Activity ◽  
Low Cost ◽  
Laccase Production ◽  
Synthetic Dyes ◽  
Phenol Red ◽  
Redox Potentials ◽  
Agroindustrial Waste ◽  
Optimum Production

Fungal laccases are preferred due to high redox potentials and low substrate specificity to xenobiotics including synthetic dyes. For large-scale applications, low enzyme yield and high cost of production has remained the challenge. Agroindustrial waste such as saw-dust of Terminalia superba abounds locally and was utilized as low-cost alternative substrate for laccase production in Solid State Bioprocessing (SSB) using Trametes sp. isolate G31. The study optimized laccase production using various parameters. Optimal production of laccase was at pH 5.0 - 7.0 with 2356 U/mL - 2369 U/mL and 25°C (2336 U/mL). Among the sources of nitrogen and carbon tested, laccase production in ammonium sulphate and sucrose supplemented media were higher. The effect of activators on laccases production showed that Cu2+ and Ca2+induced high titres of laccase at 4 -5 mM and 2 - 4 mM respectively, while production of laccase by Mn2+ was significantly high at 40 mM. The effect of 2, 2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), guaiacol and varatryl alcohol on laccase production was significantly different especially in glycerol. Optimum production for laccase was on day 14 with 2356 U/mL followed by steady declined up to day 34. The purified laccase had a specific activity of 5008 µmol/min/mg, purification factor of 3.85, and a molecular mass of ~40 kDa using N-PAGE. The potential of crude laccase to decolourize diverse dyes was tested. Phenol red achieved 40% decolourization for 1hr, while RBBR (93%), Crystal violet (60%), Methylene blue (53%) and Congo red (51%) for 24 hr, 72 hr, 48 hr and 120 hr respectively. Methyl red and Malachite green attained 42% (72 hr) and 32% (48 hr) decolourization. The enzyme ability to oxidize Phenol red and other synthetic dyes without mediators made it eco-friendly in treating dye wastewaters.

scholarly journals BonMOLière: Small-Sized Libraries of Readily Purchasable Compounds, Optimized to Produce Genuine Hits in Biological Screens across the Protein Space

2021 ◽  
Vol 22 (15) ◽  
pp. 7773
Author(s):  
Neann Mathai ◽  
Conrad Stork ◽  
Johannes Kirchmair
Keyword(s):  
Large Scale ◽  
Computational Approach ◽  
Large Sets ◽  
Compound Libraries ◽  
Wide Range ◽  
Protein Space ◽  
High Chance ◽  
Large Scale Screening ◽  
Early Drug ◽  
Selection Of

Experimental screening of large sets of compounds against macromolecular targets is a key strategy to identify novel bioactivities. However, large-scale screening requires substantial experimental resources and is time-consuming and challenging. Therefore, small to medium-sized compound libraries with a high chance of producing genuine hits on an arbitrary protein of interest would be of great value to fields related to early drug discovery, in particular biochemical and cell research. Here, we present a computational approach that incorporates drug-likeness, predicted bioactivities, biological space coverage, and target novelty, to generate optimized compound libraries with maximized chances of producing genuine hits for a wide range of proteins. The computational approach evaluates drug-likeness with a set of established rules, predicts bioactivities with a validated, similarity-based approach, and optimizes the composition of small sets of compounds towards maximum target coverage and novelty. We found that, in comparison to the random selection of compounds for a library, our approach generates substantially improved compound sets. Quantified as the “fitness” of compound libraries, the calculated improvements ranged from +60% (for a library of 15,000 compounds) to +184% (for a library of 1000 compounds). The best of the optimized compound libraries prepared in this work are available for download as a dataset bundle (“BonMOLière”).

scholarly journals Large-scale screening and characterization of enteroviruses and kobuviruses infecting pigs in Vietnam

2016 ◽  
Vol 97 (2) ◽  
pp. 378-388 ◽  
Author(s):  
Nguyen Van Dung ◽  
Pham Hong Anh ◽  
Nguyen Van Cuong ◽  
Ngo Thi Hoa ◽  
Juan Carrique-Mas ◽  
...  
Keyword(s):  
Large Scale ◽  
Large Scale Screening

scholarly journals Morphological characterization of seed-borne fungi associated with BRRI rice varieties in Bangladesh

2020 ◽  
Vol 29 (1) ◽  
pp. 75-86
Author(s):  
Tania Sultana ◽  
MA Bashar ◽  
Shamim Shamsi
Keyword(s):  
Trichoderma Viride ◽  
Morphological Characterization ◽  
Fungal Species ◽  
Curvularia Lunata ◽  
Rhizopus Stolonifer ◽  
Rice Varieties ◽  
Fusarium Equiseti ◽  
Syncephalastrum Racemosum ◽  
Planting Method

Twenty five fungal species, representing 13 genera were found to be associated with seeds of 20 varieties of rice (BRRI dhan 56 to BRRI dhan 75). Fungi were isolated following "Tissue planting" method and "Blotter method". The isolated fungi were Alternaria alternata, A. tenuissima, Aspergillus flavus, A. fumigatus, A. niger, A. ochraceus, A. terreus, Bipolaris multiformis, B. oryzae, B. sorokiniana, Chaetomium globosum, Curvularia lunata, Fusarium equiseti, F. fugikuroi, F. oxysporum, F. proliferatum, Microdochium fisheri, Nigrospora oryzae, Penicillium sp., Pestalotiopsis oxyanthi, Phanerochaete chrysosporium, Rhizopus stolonifer, Sarocladium oryzae, Syncephalastrum racemosum and Trichoderma viride. Dhaka Univ. J. Biol. Sci. 29(1): 75-86, 2020 (January)

scholarly journals ISOLATION AND CHARACTERIZATION OF NEUROSPORA MUTANTS AFFECTED IN INVERTASE SYNTHESIS

Genetics ◽  
1984 ◽  
Vol 106 (4) ◽  
pp. 591-599
Author(s):  
Deborah B Lee ◽  
Stephen J Free
Keyword(s):  
Neurospora Crassa ◽  
Large Scale ◽  
Invertase Activity ◽  
Free Medium ◽  
Wild Type ◽  
Isolation And Characterization ◽  
Normal Enzyme ◽  
Enzyme Molecules ◽  
Large Scale Screening

ABSTRACT We have outlined a procedure that allows the large-scale screening of mutagenized Neurospora crassa populations for invertaseless mutants. We have isolated and characterized three mutations, inv(DBL1), inv(DBL9) and inv(DBL14), which have been mapped at or near the invertase structural gene. One of these, inv(DBL1), is particularly interesting. Our experiments indicate that the reduced level of invertase activity in the inv(DBL1)-containing cell can be explained as the result of a reduced number of normal enzyme molecules. We also show that wild-type Neurospora is able to respond rapidly to a change of medium and can dramatically increase its production of invertase within 20 min after a transfer to a carbon-free medium.

scholarly journals Fabry-Perot spectroscopy: a powerful method for detecting superbubbles in galaxy discs

2014 ◽  
Vol 10 (S309) ◽  
pp. 303-303
Author(s):  
A. Camps-Fariña ◽  
J. Beckman ◽  
J. Zaragoza-Cardiel ◽  
J. Font ◽  
K. Fathi
Keyword(s):  
Large Scale ◽  
Massive Star ◽  
Line Of Sight ◽  
Line Profiles ◽  
Large Scale Structures ◽  
Wide Range ◽  
Fabry Perot ◽  
Projection Effect ◽  
Scale Structures

AbstractWe present a new method for the detection and characterization of large scale expansion in galaxy discs based on Hα Fabry-Perot spectroscopy, taking advantage of the high spatial and velocity resolution of our instrument (GHαFaS). The method analyses multi-peaked emission line profiles to find expansion along the line of sight on a pixel-by-pixel basis. At this stage we have centred our attention on the large scale structures of expansive gas which show a coherent gradient of velocities from their centres as a result of both bubble shape and projection effect. The results show a wide range of expansion velocities in these superbubbles, ranging from 30-150 km/s, with the expected trend of finding the higher velocities in the more violent areas of the galaxies. We have applied the technique to the Antennae and M83, obtaining spectacular results, and used these to investigate to what extent kinematically derived ages can be found and used to characterize the ages of their massive star clusters.

scholarly journals Molecular Detection and Characterization of the First Cowpox Virus Isolate Derived from a Bank Vole

Viruses ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1075 ◽  
Author(s):  
Kathrin Jeske ◽  
Saskia Weber ◽  
Florian Pfaff ◽  
Christian Imholt ◽  
Jens Jacob ◽  
...  
Keyword(s):  
Bank Vole ◽  
Large Scale ◽  
Reservoir Host ◽  
Myodes Glareolus ◽  
Phenotypic Characterization ◽  
Cowpox Virus ◽  
Bank Voles ◽  
Wide Range ◽  
Common Voles

Cowpox virus (CPXV) is a zoonotic orthopoxvirus (OPV) that infects a wide range of mammals. CPXV-specific DNA and antibodies were detected in different vole species, such as common voles (Microtus arvalis) and bank voles (Myodes glareolus). Therefore, voles are the putative main reservoir host of CPXV. However, CPXV was up to now only isolated from common voles. Here we report the detection and isolation of a bank vole-derived CPXV strain (GerMygEK 938/17) resulting from a large-scale screening of bank voles collected in Thuringia, Germany, during 2017 and 2018. Phylogenetic analysis using the complete viral genome sequence indicated a high similarity of the novel strain to CPXV clade 3 and to OPV “Abatino” but also to Ectromelia virus (ECTV) strains. Phenotypic characterization of CPXV GerMygEK 938/17 using inoculation of embryonated chicken eggs displayed hemorrhagic pock lesions on the chorioallantoic membrane that are typical for CPXV but not for ECTV. CPXV GerMygEK 938/17 replicated in vole-derived kidney cell lines but at lower level than on Vero76 cell line. In conclusion, the first bank vole-derived CPXV isolate provides new insights into the genetic variability of CPXV in the putative reservoir host and is a valuable tool for further studies about CPXV-host interaction and molecular evolution of OPV.

scholarly journals Heterologous Expression and Biochemical Characterization of a Peanut Bowman-Birk Type Inhibitor

2021 ◽  
Author(s):  
Lei Cheng ◽  
Kangming Tian ◽  
Nokuthula Peace Mchunu ◽  
Dandan Niu ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Inhibitory Activity ◽  
Large Scale ◽  
Biochemical Characterization ◽  
Scale Production ◽  
Current Investigation ◽  
Large Scale Production ◽  
Wide Range ◽  
Maximal Yield

Abstract Objectives To heterologously express peanut ( Arachis ipaensis ) Bowman-Birk inhibitor (BBI) and characterize its properties. Results A putative BBI gene from peanut was overexpressed in Pichia pastoris with the maximal yield of 11.1 mg/L in a 250-mL shaking flask fermentation. The recombinant peanut BBI (rPBBI) was purified and its molecular weight was estimated to be 9 kDa. Purified rPBBI showed 5223.6 TIA/mg inhibitory activity toward trypsin. It retained more than 95% of its inhibitory activity over wide range of temperatures (40 to 90 o C) and pH (2.0 to 10.0) after incubation for 60 min. When presence of 100 mM dithiothreitol, rPBBI lost more than 80% inhibitory activity in 30 min. Conclusion The current investigation expressed a peanut BBI with stable inhibitory activity against trypsin and exposed the potential of heterologous overexpression approach in large scale production of BBI.

scholarly journals Purification and Characterization of Nitphym, a Robust Thermostable Nitrilase From Paraburkholderia phymatum

2021 ◽  
Vol 9 ◽  
Author(s):  
Thomas Bessonnet ◽  
Aline Mariage ◽  
Jean-Louis Petit ◽  
Virginie Pellouin ◽  
Adrien Debard ◽  
...  
Keyword(s):  
Large Scale ◽  
Industrial Applications ◽  
Purification And Characterization ◽  
Thermostable Enzymes ◽  
Major Interest ◽  
Wide Range ◽  
Ph Range ◽  
Thermophilic Organisms ◽  
Hydrolysis Of

Despite the success of some nitrilases in industrial applications, there is a constant demand to broaden the catalog of these hydrolases, especially robust ones with high operational stability. By using the criteria of thermoresistance to screen a collection of candidate enzymes heterologously expressed in Escherichia coli, the enzyme Nitphym from the mesophilic organism Paraburkholderia phymatum was selected and further characterized. Its quick and efficient purification by heat treatment is of major interest for large-scale applications. The purified nitrilase displayed a high thermostability with 90% of remaining activity after 2 days at 30°C and a half-life of 18 h at 60°C, together with a broad pH range of 5.5–8.5. Its high resistance to various miscible cosolvents and tolerance to high substrate loadings enabled the quantitative conversion of 65.5 g⋅L–1 of 3-phenylpropionitrile into 3-phenylpropionic acid at 50°C in 8 h at low enzyme loadings of 0.5 g⋅L–1, with an isolated yield of 90%. This study highlights that thermophilic organisms are not the only source of industrially relevant thermostable enzymes and extends the scope of efficient nitrilases for the hydrolysis of a wide range of nitriles, especially trans-cinnamonitrile, terephthalonitrile, cyanopyridines, and 3-phenylpropionitrile.

scholarly journals Experience of short term earthquake precursors with VLF–VHF electromagnetic emissions

2003 ◽  
Vol 3 (3/4) ◽  
pp. 217-228 ◽  
Author(s):  
K. Eftaxias ◽  
P. Kapiris ◽  
J. Polygiannakis ◽  
A. Peratzakis ◽  
J. Kopanas ◽  
...  
Keyword(s):  
Earthquake Prediction ◽  
Large Scale ◽  
Field Measurements ◽  
Short Term ◽  
Wide Range ◽  
Electromagnetic Emissions ◽  
Electro Magnetic ◽  
Focal Zone

Abstract. Electromagnetic anomalies (EMA) covering a wide range of frequencies from ULF, VLF up to VHF have been observed before recent destructive earthquakes in continental Greece. We show that the features of these signals are possibly correlated with the fault model characteristics of the associated earthquake and with the degree of geotectonic heterogeneity within the focal zone. The time evolution of these electromagnetic sequences reveals striking similarities to that observed in laboratory acoustic and electromagnetic emissions during different stages of failure preparation process in rocks. If we consider that the same dynamics governs the large-scale earthquakes and the microscopic scale sample rheological structure, the results of this analysis suggest that the recorded EMA might reflect the nucleation phase of the associated impending earthquake. We focus on the rise of the statistical view of earthquakes. We find electro-magnetic fingerprints of an underlying critical mechanism. Finally, we conclude that it is useful to combine ULF and VLF-VHF field measurements in an attempt to enhance the understanding of the physics behind these observations and thus to improve the quality of earthquake prediction. Further, the identification of an EMA as a seismogenic one supports the characterization of a sequence of shocks as foreshocks at the time they occur, further helping the earthquake prediction effort.

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