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Grujić M, Dojnov B, Potočnik I, Atanasova L, Duduk B, Srebotnik E, Druzhinina IS, Kubicek CP, Vujčić Z. Superior cellulolytic activity of Trichoderma guizhouense on raw wheat straw. World J Microbiol Biotechnol 2019; 35:194. [PMID: 31776792 DOI: 10.1007/s11274-019-2774-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/21/2019] [Indexed: 01/22/2023]
Abstract
Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently attracted attention as a renewable resource for production of biofuels and commodity chemicals that could replace fossil resources. Due to its recalcitrant nature, it must be pretreated by chemical, physical or biological means prior to hydrolysis, introducing additional costs. In this paper, we tested the hypothesis that fungi which thrive on lignocellulosic material (straw, bark or soil) would be efficient in degrading untreated lignocellulose. Wheat straw was used as a model. We developed a fast and simple screening method for cellulase producers and tested one hundred Trichoderma strains isolated from wheat straw. The most potent strain-UB483FTG2/ TUCIM 4455, was isolated from substrate used for mushroom cultivation and was identified as T. guizhouense. After optimization of growth medium, high cellulase activity was already achieved after 72 h of fermentation on raw wheat straw, while the model cellulase overproducing strain T. reesei QM 9414 took 170 h and reached only 45% of the cellulase activity secreted by T. guizhouense. Maximum production levels were 1.1 U/mL (measured with CMC as cellulase substrate) and 0.7 U/mL (β-glucosidase assay). The T. guizhouense cellulase cocktail hydrolyzed raw wheat straw within 35 h. Our study shows that screening for fungi that successfully compete for special substrates in nature will lead to the isolation of strains with qualitatively and quantitatively superior enzymes needed for their digestion which could be used for industrial purposes.
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Affiliation(s)
- Marica Grujić
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
| | - Biljana Dojnov
- Department of Chemistry, Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia.
| | - Ivana Potočnik
- Laboratory of Applied Phytopathology, Institute of Pesticides and Environmental Protection, Banatska 31b, PO Box 163, Belgrade, Serbia
| | - Lea Atanasova
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,Institute of Food Technology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Bojan Duduk
- Laboratory of Applied Phytopathology, Institute of Pesticides and Environmental Protection, Banatska 31b, PO Box 163, Belgrade, Serbia
| | - Ewald Srebotnik
- Bioresource Technology Group, Research Division of Bioresources and Plant Science, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Getreidemarkt 9/E166-A, 1060, Vienna, Austria
| | - Irina S Druzhinina
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Christian P Kubicek
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,, Steinschötelgasse 7, 1100, Vienna, Austria
| | - Zoran Vujčić
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
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Kontár S, Varečka L, Híreš M, Kryštofová S, Šimkovič M. Light-induced conidiation of Trichoderma spp. strains is accompanied by development-dependent changes in the Ca 2+ binding to cell walls. Can J Microbiol 2018; 64:856-864. [PMID: 29906398 DOI: 10.1139/cjm-2017-0747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of light on the binding of Ca2+ to mycelia and to cell walls isolated from aerial mycelia of three strains of Trichoderma spp. was studied. Two independent methods were used to measure the total Ca2+ content in mycelia and the Ca2+ bound to cell walls isolated from aerial mycelia. The results of these methods showed that the light-induced formation and maturation of conidia in Trichoderma spp. is accompanied by increased Ca2+ deposition in mycelia and cell walls. Moreover, the cultivation of Trichoderma atroviride F-534 in the presence of 45Ca2+ under circadian illumination showed that radioactivity was exclusively localized in the light-induced conidial rings of aerial mycelia. The fluorescence microscopy of chlortetracycline-stained mycelia showed that the major fraction of Ca2+ was accumulated in conidia and fructification structures, or some intracellular compartments in T. atroviride F-534 grown under circadian illumination, while only a limited amount of Ca2+ was associated with hyphal surfaces. In addition, the study of 45Ca2+ binding to cell walls revealed that T. atroviride F-534 displays both increased 45Ca2+ binding capacity and elevated affinity to 45Ca2+ binding upon illumination. The results indicate that conidia formation and (or) maturation is associated with changes in Ca2+ homeostasis.
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Affiliation(s)
- Szilvia Kontár
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic.,b Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - L'udovít Varečka
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Michal Híreš
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Svetlana Kryštofová
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Martin Šimkovič
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
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