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Reppke MJ, Gerstner R, Windeisen-Holzhauser E, Richter K, Benz JP. Press water from the mechanical drying of Douglas-fir wood chips has multiple beneficial effects on lignocellulolytic fungi. Fungal Biol Biotechnol 2022; 9:10. [PMID: 35606847 PMCID: PMC9128199 DOI: 10.1186/s40694-022-00141-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/10/2022] [Indexed: 12/05/2022] Open
Abstract
Background The mechanical drying of wood chips is an innovative method that improves the heating value of sawmill by-products in an energy-efficient continuous process. The liquid that comes out of the wood chips as press water (PW), however, contains a variety of undissolved as well as dissolved organic substances. The disposal of the PW as wastewater would generate additional costs due to its high organic load, offsetting the benefits in energy costs associated with the enhanced heating value of the wood chips. Our research explored if the organic load in PW could be utilized as a substrate by cellulolytic filamentous fungi. Hence, using the industrially relevant Ascomycete Trichoderma reesei RUT-C30 as well as several Basidiomycete wood-rotting fungi, we examined the potential of press water obtained from Douglas-fir wood chips to be used in the growth and enzyme production media. Results The addition of PW supernatant to liquid cultures of T. reesei RUT-C30 resulted in a significant enhancement of the endoglucanase and endoxylanase activities with a substantially shortened lag-phase. A partial replacement of Ca2+, Mg2+, K+, as well as a complete replacement of Fe2+, Mn2+, Zn2+ by supplementing PW of the liquid media was achieved without negative effects on enzyme production. Concentrations of PW above 50% showed no adverse effects regarding the achievable endoglucanase activity but affected the endoxylanase activity to some extent. Exploring the enhancing potential of several individual PW components after chemical analysis revealed that the observed lag-phase reduction of T. reesei RUT-C30 was not caused by the dissolved sugars and ions, nor the wood particles in the PW sediment, suggesting that other, so far non-identified, compounds are responsible. However, also the growth rate of several basidiomycetes was significantly enhanced by the supplementation of raw PW to the agar medium. Moreover, their cultivation in liquid cultures reduced the turbidity of the PW substantially. Conclusions PW was identified as a suitable media supplement for lignocellulolytic fungi, including the cellulase and xylanase producer T. reesei RUT-C30 and several wood-degrading basidiomycetes. The possibility to replace several minerals, trace elements and an equal volume of fresh water in liquid media with PW and the ability of fungal mycelia to filter out the suspended solids is a promising way to combine biological wastewater treatment with value-adding biotechnological applications. Supplementary Information The online version contains supplementary material available at 10.1186/s40694-022-00141-y.
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Sun N, Liu X, Wang X, Shi H, Zhang H, Li L, Na W, Guan Q. Optimization of fermentation conditions for the production of acidophilic β-glucosidase by Trichoderma reesei S12 from mangrove soil. BIOTECHNOL BIOTEC EQ 2022. [DOI: 10.1080/13102818.2021.1984989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Nan Sun
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Xiaoxuan Liu
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Xuemei Wang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Huiyu Shi
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Haiwen Zhang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Lianbin Li
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Wei Na
- Lab of Animal Genetics, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Qingfeng Guan
- Lab of Microorganism Resource and Utilization Research, School of Life Sciences, Hainan University, Haikou, Hainan, P.R.China
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Havukainen S, Valkonen M, Koivuranta K, Landowski CP. Studies on sugar transporter CRT1 reveal new characteristics that are critical for cellulase induction in Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:158. [PMID: 32944074 PMCID: PMC7491124 DOI: 10.1186/s13068-020-01797-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/03/2020] [Indexed: 05/08/2023]
Abstract
BACKGROUND Trichoderma reesei is an ascomycete fungus that has a tremendous capability of secreting extracellular proteins, mostly lignocellulose-degrading enzymes. Although many aspects of the biology of this organism have been unfolded, the roles of the many sugar transporters coded in its genome are still a mystery with a few exceptions. One of the most interesting sugar transporters that has thus far been discovered is the cellulose response transporter 1 (CRT1), which has been suggested to be either a sugar transporter or a sensor due to its seemingly important role in cellulase induction. RESULTS Here we show that CRT1 is a high-affinity cellobiose transporter, whose function can be complemented by the expression of other known cellobiose transporters. Expression of two sequence variants of the crt1 gene in Saccharomyces cerevisiae revealed that only the variant listed in the RUT-C30 genome annotation has the capability to transport cellobiose and lactose. When expressed in the Δ crt1 strain, the variant listed in the QM6a genome annotation offers partial complementation of the cellulase induction, while the expression of the RUT-C30 variant or cellobiose transporters from two other fungal species fully restore the cellulase induction. CONCLUSIONS These results add to our knowledge about the fungal metabolism of cellulose-derived oligosaccharides, which have the capability of inducing the cellulase production in many species. They also help us to deepen our understanding of the T. reesei lactose metabolism, which can have important consequences as this sugar is used as the inducer of protein secretion in many industrial processes which employ this species.
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Affiliation(s)
- Sami Havukainen
- VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
| | - Mari Valkonen
- VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
| | - Kari Koivuranta
- VTT Technical Research Center of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
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Randhawa A, Ogunyewo OA, Eqbal D, Gupta M, Yazdani SS. Disruption of zinc finger DNA binding domain in catabolite repressor Mig1 increases growth rate, hyphal branching, and cellulase expression in hypercellulolytic fungus Penicillium funiculosum NCIM1228. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:15. [PMID: 29416560 PMCID: PMC5784589 DOI: 10.1186/s13068-018-1011-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 01/08/2018] [Indexed: 05/31/2023]
Abstract
BACKGROUND There is an urgent requirement for second-generation bio-based industries for economical yet efficient enzymatic cocktail to convert diverse cellulosic biomass into fermentable sugars. In our previous study, secretome of Penicillium funiculosum NCIM1228 showed high commercial potential by exhibiting high biomass hydrolyzing efficiency. To develop NCIM1228 further as an industrial workhorse, one of the major genetic interventions needed is global deregulation of cellulolytic genes to achieve higher enzyme production. Mig1 orthologs found in all yeast and filamentous fungi are transcriptional regulators that maintain carbon homeostasis by negatively regulating genes of secondary carbon source utilization. Their disruption has long been known to be beneficial for increasing the production of secreted enzymes for alternate carbon source utilization. RESULTS Upon detailed genotypic and phenotypic analysis, we observed that NCIM1228 harbors a truncated yet functional allele of homolog of a well-known catabolite repressor, Mig1. Alleviation of carbon repression in NCIM1228 was attained by replacing functional Mig1134 allele with null allele Mig188. P. funiculosum having Mig188 null allele showed better growth characteristics and 1.75-fold better glucose utilization than parent strain. We also showed that visibly small colony size, one of the major characteristics of CCR disruptant strains in filamentous fungi, was not due to retarded growth, but altered hyphal morphology. CCR-disrupted strain PfMig188 showed profuse branching pattern in terminal hyphae resulting in small and compact colonies with compromised filamentous proliferation. We further observed that basal level expression of two major classes of cellulases, namely, cellobiohydrolase and endoglucanase, was regulated by Mig1134 in NCIM1228, whereas other two major classes, namely, xylanases and β-glucosidase, were only marginally regulated. Finally, CCR disruption in P. funiculosum NCIM1228 led to prolonged cellulase induction in production medium resulting in twofold increased cellulase activity than the parent strain with maximum secreted protein titer being > 14 g/l. CONCLUSIONS CCR-disrupted P. funiculosum showed better growth, enhanced carbon source utilization, profuse branching pattern in terminal hyphae, and higher cellulase activity than parent strain. Our findings are particularly important in shedding light on important functions performed by Mig1 in addition to its role as negative regulator of alternate carbon source utilization in filamentous fungi.
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Affiliation(s)
- Anmoldeep Randhawa
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067 India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Olusola A. Ogunyewo
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067 India
| | - Danish Eqbal
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067 India
| | - Mayank Gupta
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067 India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067 India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
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Zang X, Liu M, Fan Y, Xu J, Xu X, Li H. The structural and functional contributions of β-glucosidase-producing microbial communities to cellulose degradation in composting. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:51. [PMID: 29492106 PMCID: PMC5828080 DOI: 10.1186/s13068-018-1045-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 02/06/2018] [Indexed: 05/04/2023]
Abstract
BACKGROUND Compost habitats sustain a vast ensemble of microbes that engender the degradation of cellulose, which is an important part of global carbon cycle. β-Glucosidase is the rate-limiting enzyme of degradation of cellulose. Thus, analysis of regulation of β-glucosidase gene expression in composting is beneficial to a better understanding of cellulose degradation mechanism. Genetic diversity and expression of β-glucosidase-producing microbial communities, and relationships of cellulose degradation, metabolic products and the relative enzyme activity during natural composting and inoculated composting were evaluated. RESULTS Compared with natural composting, adding inoculation agent effectively improved the degradation of cellulose, and maintained high level of the carboxymethyl cellulose (CMCase) and β-glucosidase activities in thermophilic phase. Gene expression analysis showed that glycoside hydrolase family 1 (GH1) family of β-glucosidase genes contributed more to β-glucosidase activity in the later thermophilic phase in inoculated compost. In the cooling phase of natural compost, glycoside hydrolase family 3 (GH3) family of β-glucosidase genes contributed more to β-glucosidase activity. Intracellular β-glucosidase activity played a crucial role in the regulation of β-glucosidase gene expression, and upregulation or downregulation was also determined by extracellular concentration of glucose. At sufficiently high glucose concentrations, the functional microbial community in compost was altered, which may contribute to maintaining β-glucosidase activity despite the high glucose content. CONCLUSION This research provides an ecological functional map of microorganisms involved in carbon metabolism in cattle manure-rice straw composting. The performance of the functional microbial groups in the two composting treatments is different, which is related to the cellulase activity and cellulose degradation, respectively.
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Affiliation(s)
- Xiangyun Zang
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Meiting Liu
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Yihong Fan
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Jie Xu
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Xiuhong Xu
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Hongtao Li
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
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The influence of soluble polysaccharides derived from rice straw upon cellulase production by Trichoderma reesei. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.06.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Bi R, Berglund J, Vilaplana F, McKee LS, Henriksson G. The degree of acetylation affects the microbial degradability of mannans. Polym Degrad Stab 2016. [DOI: 10.1016/j.polymdegradstab.2016.07.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Antonov E, Wirth S, Gerlach T, Schlembach I, Rosenbaum MA, Regestein L, Büchs J. Efficient evaluation of cellulose digestibility by Trichoderma reesei Rut-C30 cultures in online monitored shake flasks. Microb Cell Fact 2016; 15:164. [PMID: 27686382 PMCID: PMC5043636 DOI: 10.1186/s12934-016-0567-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 09/22/2016] [Indexed: 11/10/2022] Open
Abstract
Background Pretreated lignocellulosic biomass is considered as a suitable feedstock for the sustainable production of chemicals. However, the recalcitrant nature of cellulose often results in very cost-intensive overall production processes. A promising concept to reduce the costs is consolidated bioprocessing, which integrates in a single step cellulase production, cellulose hydrolysis, and fermentative conversion of produced sugars into a valuable product. This approach, however, requires assessing the digestibility of the applied celluloses and, thus, the released sugar amount during the fermentation. Since the released sugars are completely taken up by Trichoderma reesei Rut-C30 and the sugar consumption is stoichiometrically coupled to oxygen uptake, the respiration activity was measured to evaluate the digestibility of cellulose. Results The method was successfully tested on commercial cellulosic substrates identifying a correlation between the respiration activity and the crystallinity of the substrate. Pulse experiments with cellulose and cellulases suggested that the respiration activity of T. reesei on cellulose can be divided into two distinct phases, one limited by enzyme activity and one by cellulose-binding-sites. The impact of known (cellobiose, sophorose, urea, tween 80, peptone) and new (miscanthus steepwater) compounds enhancing cellulase production was evaluated. Furthermore, the influence of two different pretreatment methods, the OrganoCat and OrganoSolv process, on the digestibility of beech wood saw dust was tested. Conclusions The introduced method allows an online evaluation of cellulose digestibility in complex and non-complex cultivation media. As the measurements are performed under fermentation conditions, it is a valuable tool to test different types of cellulose for consolidated bioprocessing applications. Furthermore, the method can be applied to identify new compounds, which influence cellulase production. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0567-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elena Antonov
- AVT‑Biochemical Engineering, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Steffen Wirth
- AVT‑Biochemical Engineering, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Tim Gerlach
- AVT‑Biochemical Engineering, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Ivan Schlembach
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Miriam A Rosenbaum
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Lars Regestein
- AVT‑Biochemical Engineering, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Jochen Büchs
- AVT‑Biochemical Engineering, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.
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Shida Y, Furukawa T, Ogasawara W. Deciphering the molecular mechanisms behind cellulase production in Trichoderma reesei, the hyper-cellulolytic filamentous fungus. Biosci Biotechnol Biochem 2016; 80:1712-29. [DOI: 10.1080/09168451.2016.1171701] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Abstract
The filamentous fungus Trichoderma reesei is a potent cellulase producer and the best-studied cellulolytic fungus. A lot of investigations not only on glycoside hydrolases produced by T. reesei, but also on the machinery controlling gene expression of these enzyme have made this fungus a model organism for cellulolytic fungi. We have investigated the T. reesei strain including mutants developed in Japan in detail to understand the molecular mechanisms that control the cellulase gene expression, the biochemical and morphological aspects that could favor this phenotype, and have attempted to generate novel strains that may be appropriate for industrial use. Subsequently, we developed recombinant strains by combination of these insights and the heterologous-efficient saccharifing enzymes. Resulting enzyme preparations were highly effective for saccharification of various biomass. In this review, we present some of the salient findings from the recent biochemical, morphological, and molecular analyses of this remarkable cellulase hyper-producing fungus.
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Affiliation(s)
- Yosuke Shida
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Japan
| | - Takanori Furukawa
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Japan
| | - Wataru Ogasawara
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Japan
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Shida Y, Yamaguchi K, Nitta M, Nakamura A, Takahashi M, Kidokoro SI, Mori K, Tashiro K, Kuhara S, Matsuzawa T, Yaoi K, Sakamoto Y, Tanaka N, Morikawa Y, Ogasawara W. The impact of a single-nucleotide mutation of bgl2 on cellulase induction in a Trichoderma reesei mutant. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:230. [PMID: 26719764 PMCID: PMC4696228 DOI: 10.1186/s13068-015-0420-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 12/15/2015] [Indexed: 05/10/2023]
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei (anamorph of Hypocrea jecorina) produces increased cellulase expression when grown on cellulose or its derivatives as a sole carbon source. It has been believed that β-glucosidases of T. reesei not only metabolize cellobiose but also contribute in the production of inducers of cellulase gene expression by their transglycosylation activity. The cellulase hyper-producing mutant PC-3-7 developed in Japan has enhanced cellulase production ability when cellobiose is used as the inducer. The comparative genomics analysis of PC-3-7 and its parent revealed a single-nucleotide mutation within the bgl2 gene encoding intracellular β-glucosidase II (BGLII/Cel1a), giving rise to an amino acid substitution in PC-3-7, which could potentially account for the enhanced cellulase expression when these strains are cultivated on cellulose and cellobiose. RESULTS To analyze the effects of the BGLII mutation in cellulase induction, we constructed both a bgl2 revertant and a disruptant. Enzymatic analysis of the transformant lysates showed that the strain expressing mutant BGLII exhibited weakened cellobiose hydrolytic activity, but produced some transglycosylation products, suggesting that the SNP in bgl2 strongly diminished cellobiase activity, but did not result in complete loss of function of BGLII. The analysis of the recombinant BGLII revealed that transglycosylation products might be oligosaccharides, composed probably of glucose linked β-1,4, β-1,3, or a mixture of both. PC-3-7 revertants of bgl2 exhibited reduced expression and inducibility of cellulase during growth on cellulose and cellobiose substrates. Furthermore, the effect of this bgl2 mutation was reproduced in the common strain QM9414 in which the transformants showed cellulase production comparable to that of PC-3-7. CONCLUSION We conclude that BGLII plays an important role in cellulase induction in T. reesei and that the bgl2 mutation in PC-3-7 brought about enhanced cellulase expression on cellobiose. The results of the investigation using PC-3-7 suggested that other mutation(s) in PC-3-7 could also contribute to cellulase induction. Further investigation is essential to unravel the mechanism responsible for cellulase induction in T. reesei.
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Affiliation(s)
- Yosuke Shida
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Kaori Yamaguchi
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Mikiko Nitta
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
- />Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 Japan
| | - Ayana Nakamura
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Machiko Takahashi
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Shun-ichi Kidokoro
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Kazuki Mori
- />Department of Genetic Resources Technology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 Japan
| | - Kosuke Tashiro
- />Department of Genetic Resources Technology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 Japan
| | - Satoru Kuhara
- />Department of Genetic Resources Technology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 Japan
| | - Tomohiko Matsuzawa
- />Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566 Japan
| | - Katsuro Yaoi
- />Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566 Japan
| | - Yasumitsu Sakamoto
- />School of Pharmacy, Iwate Medical University, 2-1-1 Nishitokuta, Yahaba, Iwate 028-3694 Japan
| | - Nobutada Tanaka
- />School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555 Japan
| | - Yasushi Morikawa
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
| | - Wataru Ogasawara
- />Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 Japan
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Nogueira KMV, Costa MDN, de Paula RG, Mendonça-Natividade FC, Ricci-Azevedo R, Silva RN. Evidence of cAMP involvement in cellobiohydrolase expression and secretion by Trichoderma reesei in presence of the inducer sophorose. BMC Microbiol 2015; 15:195. [PMID: 26424592 PMCID: PMC4590280 DOI: 10.1186/s12866-015-0536-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/25/2015] [Indexed: 01/08/2023] Open
Abstract
Background The signaling second messenger cyclic AMP (cAMP) regulates many aspects of cellular function in all organisms. Previous studies have suggested a role for cAMP in the regulation of gene expression of cellulolytic enzymes in Trichoderma reesei (anamorph of Hypocrea jecorina). Methods The effects of cAMP in T. reesei were analyzed through both activity and expression of cellulase, intracellular cAMP level measurement, western blotting, indirect immunofluorescence and confocal microscopy. Results To elucidate the involvement of cAMP in the cellulase expression, we analyzed the growth of the mutant strain ∆acy1 and its parental strain QM9414 in the presence of the inducers cellulose, cellobiose, lactose, or sophorose, and the repressor glucose. Our results indicated that cAMP regulates the expression of cellulase in a carbon source-dependent manner. The expression cel7a, and cel6a genes was higher in the presence of sophorose than in the presence of cellulose, lactose, cellobiose, or glucose. Moreover, intracellular levels of cAMP were up to four times higher in the presence of sophorose compared to other carbon sources. Concomitantly, our immunofluorescence microscopy and western blot data suggest that in the presence of sophorose, cAMP may regulate secretion of cellulolytic enzymes in T. reesei. Conclusions These results allow us to better understand the role of cAMP and expand our knowledge on the signal transduction pathways involved in the regulation of cellulase expression in T. reesei. Finally, our data may help develop new strategies to improve the expression of cel7a and cel6a genes, and therefore, favor their application in several biotechnology fields. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0536-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karoline Maria Vieira Nogueira
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
| | - Mariana do Nascimento Costa
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
| | - Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
| | - Flávia Costa Mendonça-Natividade
- Department of Cell Biology and Molecular and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
| | - Rafael Ricci-Azevedo
- Department of Cell Biology and Molecular and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
| | - Roberto Nascimento Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
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Kou Y, Xu J, Cao Y, Lv X, Zhao G, Chen G, Zhang W, liu W. Gluconolactone induces cellulase gene expression in cellulolytic filamentous fungus Trichoderma reesei. RSC Adv 2014. [DOI: 10.1039/c4ra06731b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Gluconolactone, an inhibitor of β-glucosidase, is capable of inducing cellulase gene expression in cellulolytic filamentous fungusTrichoderma reesei.
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Affiliation(s)
- Yanbo Kou
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Jintao Xu
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Yanli Cao
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Xinxing Lv
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Guolei Zhao
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
| | - Weifeng liu
- State Key Laboratory of Microbial Technology
- School of Life Science
- Shandong University
- Jinan 250100, P. R. China
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13
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Zhang W, Kou Y, Xu J, Cao Y, Zhao G, Shao J, Wang H, Wang Z, Bao X, Chen G, Liu W. Two major facilitator superfamily sugar transporters from Trichoderma reesei and their roles in induction of cellulase biosynthesis. J Biol Chem 2013; 288:32861-72. [PMID: 24085297 DOI: 10.1074/jbc.m113.505826] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proper perception of the extracellular insoluble cellulose is key to initiating the rapid synthesis of cellulases by cellulolytic Trichoderma reesei. Uptake of soluble oligosaccharides derived from cellulose hydrolysis represents a potential point of control in the induced cascade. In this study, we identified a major facilitator superfamily sugar transporter Stp1 capable of transporting cellobiose by reconstructing a cellobiose assimilation system in Saccharomyces cerevisiae. The absence of Stp1 in T. reesei resulted in differential cellulolytic response to Avicel versus cellobiose. Transcriptional profiling revealed a different expression profile in the Δstp1 strain from that of wild-type strain in response to Avicel and demonstrated that Stp1 somehow repressed induction of the bulk of major cellulase and hemicellulose genes. Two other putative major facilitator superfamily sugar transporters were, however, up-regulated in the profiling. Deletion of one of them identified Crt1 that was required for growth and enzymatic activity on cellulose or lactose, but was not required for growth or hemicellulase activity on xylan. The essential role of Crt1 in cellulase induction did not seem to rely on its transporting activity because the overall uptake of cellobiose or sophorose by T. reesei was not compromised in the absence of Crt1. Phylogenetic analysis revealed that orthologs of Crt1 exist in the genomes of many filamentous ascomycete fungi capable of degrading cellulose. These data thus shed new light on the mechanism by which T. reesei senses and transmits the cellulose signal and offers potential strategies for strain improvement.
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Affiliation(s)
- Weixin Zhang
- From the State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, Shandong, China and
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Differential involvement of β-glucosidases from Hypocrea jecorina in rapid induction of cellulase genes by cellulose and cellobiose. EUKARYOTIC CELL 2012; 11:1371-81. [PMID: 23002106 DOI: 10.1128/ec.00170-12] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Appropriate perception of cellulose outside the cell by transforming it into an intracellular signal ensures the rapid production of cellulases by cellulolytic Hypocrea jecorina. The major extracellular β-glucosidase BglI (CEL3a) has been shown to contribute to the efficient induction of cellulase genes. Multiple β-glucosidases belonging to glycosyl hydrolase (GH) family 3 and 1, however, exist in H. jecorina. Here we demonstrated that CEL1b, like CEL1a, was an intracellular β-glucosidase displaying in vitro transglycosylation activity. We then found evidence that these two major intracellular β-glucosidases were involved in the rapid induction of cellulase genes by insoluble cellulose. Deletion of cel1a and cel1b significantly compromised the efficient gene expression of the major cellulase gene, cbh1. Simultaneous absence of BglI, CEL1a, and CEL1b caused the induction of the cellulase gene by cellulose to further deteriorate. The induction defect, however, was not observed with cellobiose. The absence of the three β-glucosidases, rather, facilitated the induced synthesis of cellulase on cellobiose. Furthermore, addition of cellobiose restored the productive induction on cellulose in the deletion strains. The results indicate that the three β-glucosidases may not participate in transforming cellobiose beyond hydrolysis to provoke cellulase formation in H. jecorina. They may otherwise contribute to the accumulation of cellobiose from cellulose as inducing signals.
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15
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Nitta M, Furukawa T, Shida Y, Mori K, Kuhara S, Morikawa Y, Ogasawara W. A new Zn(II)2Cys6-type transcription factor BglR regulates β-glucosidase expression in Trichoderma reesei. Fungal Genet Biol 2012; 49:388-97. [DOI: 10.1016/j.fgb.2012.02.009] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 02/07/2012] [Accepted: 02/25/2012] [Indexed: 11/25/2022]
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16
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Induction of lignocellulose-degrading enzymes in Neurospora crassa by cellodextrins. Proc Natl Acad Sci U S A 2012; 109:6012-7. [PMID: 22474347 DOI: 10.1073/pnas.1118440109] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Neurospora crassa colonizes burnt grasslands in the wild and metabolizes both cellulose and hemicellulose from plant cell walls. When switched from a favored carbon source such as sucrose to cellulose, N. crassa dramatically upregulates expression and secretion of a wide variety of genes encoding lignocellulolytic enzymes. However, the means by which N. crassa and other filamentous fungi sense the presence of cellulose in the environment remains unclear. Here, we show that an N. crassa mutant carrying deletions of two genes encoding extracellular β-glucosidase enzymes and one intracellular β-glucosidase lacks β-glucosidase activity, but efficiently induces cellulase gene expression in the presence of cellobiose, cellotriose, or cellotetraose as a sole carbon source. These data indicate that cellobiose, or a modified version of cellobiose, functions as an inducer of lignocellulolytic gene expression in N. crassa. Furthermore, the inclusion of a deletion of the catabolite repressor gene, cre-1, in the triple β-glucosidase mutant resulted in a strain that produces higher concentrations of secreted active cellulases on cellobiose. Thus, the ability to induce cellulase gene expression using a common and soluble carbon source simplifies enzyme production and characterization, which could be applied to other cellulolytic filamentous fungi.
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17
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Adav SS, Chao LT, Sze SK. Quantitative secretomic analysis of Trichoderma reesei strains reveals enzymatic composition for lignocellulosic biomass degradation. Mol Cell Proteomics 2012; 11:M111.012419. [PMID: 22355001 DOI: 10.1074/mcp.m111.012419] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Trichoderma reesei is a mesophilic, filamentous fungus, and it is a major industrial source of cellulases, but its lignocellulolytic protein expressions on lignocellulosic biomass are poorly explored at present. The extracellular proteins secreted by T. reesei QM6a wild-type and hypercellulolytic mutant Rut C30 grown on natural lignocellulosic biomasses were explored using a quantitative proteomic approach with 8-plex high throughput isobaric tags for relative and absolute quantification (iTRAQ) and analyzed by liquid chromatography tandem mass spectrometry. We quantified 230 extracellular proteins, including cellulases, hemicellulases, lignin-degrading enzymes, proteases, protein-translocating transporter, and hypothetical proteins. Quantitative iTRAQ results suggested that the expressions and regulations of these lignocellulolytic proteins in the secretome of T. reesei wild-type and mutant Rut C30 were dependent on both nature and complexity of different lignocellulosic carbon sources. Therefore, we discuss here the essential lignocellulolytic proteins for designing an enzyme mixture for optimal lignocellulosic biomass hydrolysis.
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Affiliation(s)
- Sunil S Adav
- School of Biological Sciences, Nanyang Technological University, Singapore
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18
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Seiboth B, Herold S, Kubicek CP. Metabolic engineering of inducer formation for cellulase and hemicellulase gene expression in Trichoderma reesei. Subcell Biochem 2012; 64:367-90. [PMID: 23080260 DOI: 10.1007/978-94-007-5055-5_18] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The filamentous fungus T. reeseiis today a paradigm for the commercial scale production of different plant cell wall degrading enzymes mainly cellulases and hemicellulases. Its enzymes have a long history of safe use in industry and well established applications are found within the pulp, paper, food, feed or textile processing industries. However, when these enzymes are to be used for the saccharification of cellulosic plant biomass to simple sugars which can be further converted to biofuels or other biorefinery products, and thus compete with chemicals produced from fossil sources, additional efforts are needed to reduce costs and maximize yield and efficiency of the produced enzyme mixtures. One approach to this end is the use of genetic engineering to manipulate the biochemical and regulatory pathways that operate during enzyme production and control enzyme yield. This review aims at a description of the state of art in this area.
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Affiliation(s)
- Bernhard Seiboth
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, Vienna University of Technology, Gumpendorferstraße 1a, 166-5, A-1060, Vienna, Austria
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19
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Wei X, Zheng K, Chen M, Liu G, Li J, Lei Y, Qin Y, Qu Y. Transcription analysis of lignocellulolytic enzymes of Penicillium decumbens 114-2 and its catabolite-repression-resistant mutant. C R Biol 2011; 334:806-11. [PMID: 22078737 DOI: 10.1016/j.crvi.2011.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Penicillium decumbens 114-2 is a fast-growing filamentous fungus which secretes a variety of lignocellulolytic enzymes. Its catabolite-repression-resistant mutant JU-A10 with high secretion capacity of cellulolytic enzymes has been used industrially for biomass hydrolysis. Transcription levels of 6 important lignocellulolytic enzymes genes (cel5A, cel6A, cel7A, cel7B, xyn10A, and xyn11A) from both strains were determined on different carbon sources (glucose, sorbose, lactose, cellobiose, cellulose, and cellulose-wheat bran), by means of a real-time quantitative polymerase chain reaction. For both strains, the 6 genes are coordinately regulated at transcriptional level. Glucose and cellobiose repressed whereas cellulose and cellulose-wheat bran induced expression of 6 genes in both strains. Expression levels of all genes tested in the mutant strain JU-A10 were substantially higher than those in wild-type strain 114-2 on all carbon sources. On glucose repression condition, the mutant JU-A10 appeared obviously derepressed. Lactose was first proved to have an inductive effect on lignocellulolytic enzyme genes expression at lower concentration in Penicillium spp.
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Affiliation(s)
- Xiaomin Wei
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, PR China
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20
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Dehydrogenase GRD1 represents a novel component of the cellulase regulon in Trichoderma reesei (Hypocrea jecorina). Appl Environ Microbiol 2011; 77:4553-63. [PMID: 21602376 DOI: 10.1128/aem.00513-11] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trichoderma reesei (Hypocrea jecorina) is nowadays the most important industrial producer of cellulase and hemicellulase enzymes, which are used for pretreatment of cellulosic biomass for biofuel production. In this study, we introduce a novel component, GRD1 (glucose-ribitol dehydrogenase 1), which shows enzymatic activity on cellobiose and positively influences cellulase gene transcription, expression, and extracellular endo-1,4-β-D-glucanase activity. grd1 is differentially transcribed upon growth on cellulose and the induction of cellulase gene expression by sophorose. The transcription of grd1 is coregulated with that of cel7a (cbh1) under inducing conditions. GRD1 is further involved in carbon source utilization on several carbon sources, such as those involved in lactose and D-galactose catabolism, in several cases in a light-dependent manner. We conclude that GRD1 represents a novel enhancer of cellulase gene expression, which by coregulation with the major cellulase may act via optimization of inducing mechanisms.
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Ling M, Chen G, Lin Y, Liang Z. Induction of cellulase gene transcription by a novel oligosaccharide: molasses alcohol stillage substance. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0017-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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22
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Juhász T, Szengyel Z, Réczey K, Siika-Aho M, Viikari L. Characterization of cellulases and hemicellulases produced by Trichoderma reesei on various carbon sources. Process Biochem 2005. [DOI: 10.1016/j.procbio.2005.03.057] [Citation(s) in RCA: 183] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Acosta-Rodríguez I, Piñón-Escobedo C, Zavala-Páramo MG, López-Romero E, Cano-Camacho H. Degradation of cellulose by the bean-pathogenic fungus Colletotrichum lindemuthianum. Production of extracellular cellulolytic enzymes by cellulose induction. Antonie van Leeuwenhoek 2005; 87:301-10. [PMID: 15928983 DOI: 10.1007/s10482-004-6422-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2004] [Accepted: 11/18/2004] [Indexed: 11/26/2022]
Abstract
Colletotrichum lindemuthianum was able to grow and produce extracellular cellulolytic activity in a defined medium containing cellulose as the main carbon substrate. As measured either by the hydrolysis of 4-methylumbelliferyl-beta-D -cellotrioside or the release of glucose from carboxymethylcellulose, activity reached a peak after 13 days of incubation and then declined whereas growth markedly increased afterwards. Detection of glucose in carboxymethylcellulose hydrolysates suggested the concerted operation of endo-1,4-beta-glucanase, cellobiohydrolase (exo-1,4-beta-glucanase) and beta-glucosidase activities. The highest levels of cellulolytic activity were obtained in media supplemented with cellulose and glutamate. Other carbon and nitrogen sources markedly influenced growth and enzyme production. Oligonucleotides homologous to specific regions of the cellobiohydrolase-encoding cbhII gene from Trichoderma reesei were used to isolate a C. lindemuthianum cbhII-DNA fragment whose sequence revealed homologies of 98% and 92% with the nucleotide and the deduced amino acid sequences of the corresponding cbhII-DNA of T. reesei, respectively. RT-PCR and Southern blot analyses of total RNA samples obtained from cellulose-grown but not from glucose-grown mycelium revealed the expression of the corresponding cbhII transcript. The cbhII-cDNA fragment was cloned and sequenced.
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Affiliation(s)
- Ismael Acosta-Rodríguez
- Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, S.L.P.78320, México
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24
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Aro N, Pakula T, Penttilä M. Transcriptional regulation of plant cell wall degradation by filamentous fungi. FEMS Microbiol Rev 2004; 29:719-39. [PMID: 16102600 DOI: 10.1016/j.femsre.2004.11.006] [Citation(s) in RCA: 274] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Revised: 10/29/2004] [Accepted: 11/01/2004] [Indexed: 11/22/2022] Open
Abstract
Plant cell wall consists mainly of the large biopolymers cellulose, hemicellulose, lignin and pectin. These biopolymers are degraded by many microorganisms, in particular filamentous fungi, with the aid of extracellular enzymes. Filamentous fungi have a key role in degradation of the most abundant biopolymers found in nature, cellulose and hemicelluloses, and therefore are essential for the maintenance of the global carbon cycle. The production of plant cell wall degrading enzymes, cellulases, hemicellulases, ligninases and pectinases, is regulated mainly at the transcriptional level in filamentous fungi. The genes are induced in the presence of the polymers or molecules derived from the polymers and repressed under growth conditions where the production of these enzymes is not necessary, such as on glucose. The expression of the genes encoding the enzymes is regulated by various environmental and cellular factors, some of which are common while others are more unique to either a certain fungus or a class of enzymes. This review summarises our current knowledge on the transcriptional regulation, focusing on the recently characterized transcription factors that regulate genes coding for enzymes involved in the breakdown of plant cell wall biopolymers.
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Affiliation(s)
- Nina Aro
- VTT Biotechnology, Espoo, Finland.
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25
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Abstract
Bioconversion of cellulose to soluble sugars and glucose is catalyzed by a group of enzymes called cellulases. Microorganisms including fungi, bacteria and actinomycetes produce mainly three types of cellulase components--endo-1,4-beta-D-glucanase, exo-1,4-beta-D-glucanase and beta-glucosidase--either separately or in the form of a complex. Over the last several decades, cellulases have become better understood at a fundamental level; nevertheless, much remains to be learnt. The tremendous commercial potential of cellulases in a variety of applications remains the driving force for research in this area. This review summarizes the present state of knowledge on microbial cellulases and their applications.
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Affiliation(s)
- M K Bhat
- Food Macromolecular Science Department, Institute of Food Research Reading Laboratory, Earley Gate, Whiteknights Road, Reading, RG6 6BZ, United Kingdom
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26
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Schmoll M, Kubicek CP. Regulation of Trichoderma cellulase formation: lessons in molecular biology from an industrial fungus. A review. Acta Microbiol Immunol Hung 2003; 50:125-45. [PMID: 12894484 DOI: 10.1556/amicr.50.2003.2-3.3] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The present article reviews the current understanding of regulation of cellulase gene transcription in Hypocrea jecorina (= Trichoderma reesei). Special emphasis is put on the mechanism of action of low molecular weight inducers of cellulase formation, the presence and role of recently identified transactivating proteins (Ace1, Ace2, Hap2/3/5), and the role of the carbon catabolite repressor Cre1. We also report on some recent genomic approaches towards understanding how cellulase inducers signal their presence to the transcriptional apparatus.
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Affiliation(s)
- Monika Schmoll
- Area Molecular Biotechnology, Section Applied Biochemistry and Gene Technology, Institute for Chemical Engineering, Vienna University of Technology, Getreidemarkt 9/1665, A-1060 Wien, Austria
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27
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Zeilinger S, Haller M, Mach R, Kubicek CP. Molecular characterization of a cellulase-negative mutant of Hypocrea jecorina. Biochem Biophys Res Commun 2000; 277:581-8. [PMID: 11061997 DOI: 10.1006/bbrc.2000.3726] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The "cbh2 activating element," CAE, consisting of two separate boxes (ATTGG = CCAAT and GTAATA, respectively) is essential for cellobiohydrolase II gene expression in the filamentous fungus Hypcrea jecorina. Here we report that cell-free extracts from a cellulase-negative mutant form CAE-protein complexes with higher mobility and lower binding-strength compared to the wild type. EMSA analysis demonstrated an increased mobility of the GTAATA-binding protein complex and, supported by in vivo footprinting, a lowered binding strength of the HAP2/3/5 proteins. However, the hap2/hap3/hap5 genes of the mutant are unaltered and transcribed normally. A nucleotide fragment of the cbh1 promoter containing a (GG)CTAATA motif without an adjacent CCAAT box is also bound by cell-free extracts of H. jecorina, and the protein-DNA complex of the mutant shows the characteristic increase in mobility. We conclude that this mutant is defective in the functional formation of the CAE-protein complexes but not in their binding to the target sequences itself.
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Affiliation(s)
- S Zeilinger
- Section Microbial Biochemistry, Institute of Biochemical Technology and Microbiology, Technical University of Vienna, Getreidemarkt 9, Wien, A-1060, Austria.
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28
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Sorbose mediated enhancement of cellulase biosynthesis inTrichoderma reesei. BIOTECHNOL BIOPROC E 1999. [DOI: 10.1007/bf02931927] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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29
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Bhat S, Kennedy JF, Goodenough PW, Owen E, Bhat MK. Effect of d-glucono-1,4-lactone on the production of CMCase, pNPCase and true cellulase by Clostridium thermocellum. Carbohydr Polym 1997. [DOI: 10.1016/s0144-8617(97)00049-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Seiboth B, Hakola S, Mach RL, Suominen PL, Kubicek CP. Role of four major cellulases in triggering of cellulase gene expression by cellulose in Trichoderma reesei. J Bacteriol 1997; 179:5318-20. [PMID: 9286982 PMCID: PMC179398 DOI: 10.1128/jb.179.17.5318-5320.1997] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The relative contributions of four major cellulases of Trichoderma reesei (1,4-beta-D-glucan cellobiohydrolase I [CBH I], CBH II, endo-1,4-beta-D-glucanase I [EG I], and EG II) to the generation of the cellulase inducer from cellulose were studied with isogenic strains in which the corresponding genes (cbh1, cbh2, egl1, and egl2) had been deleted by insertion of the Aspergillus nidulans amdS marker gene. During growth on lactose (a soluble carbon source provoking cellulase gene expression), these strains showed no significant alterations in their ability to express the respective other cellulase genes, with the exception of the strain containing delta cbh1, which exhibited an increased steady-state level of cbh2 mRNA. On crystalline cellulose as the only carbon source, however, significant differences were apparent: strains in which cbh2 and egl2, respectively, had been deleted showed no expression of the other cellulase genes, whereas strains carrying the cbh1 or egl1 deletion showed these transcripts. The delta cbh1-containing strain also showed enhanced cbh2 mRNA levels under these conditions. A strain in which both cbh1 and cbh2 had been deleted, however, was unable to initiate growth on cellulose. Addition of 2 mM sophorose, a putative inducer of cellulase gene expression, to such cultures induced the transcription of egl1 and egl2 and restored the ability to grow on cellulose. We conclude that CBH II and EG II are of major importance for the efficient formation of the inducer from cellulose in T. reesei and that removal of both cellobiohydrolases renders T. reesei unable to attack crystalline cellulose.
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Affiliation(s)
- B Seiboth
- Abteilung für Mikrobielle Biochemie, Institut für Biochemische Technologie und Mikrobiologie, TU Wien, Vienna, Austria
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31
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Ilmén M, Saloheimo A, Onnela ML, Penttilä ME. Regulation of cellulase gene expression in the filamentous fungus Trichoderma reesei. Appl Environ Microbiol 1997; 63:1298-306. [PMID: 9097427 PMCID: PMC168424 DOI: 10.1128/aem.63.4.1298-1306.1997] [Citation(s) in RCA: 263] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Basic features of regulation of expression of the genes encoding the cellulases of the filamentous fungus Trichoderma reesei QM9414, the genes cbh1 and cbh2 encoding cellobiohydrolases and the genes egl1, egl2 and egl5 encoding endoglucanases, were studied at the mRNA level. The cellulase genes were coordinately expressed under all conditions studied, with the steady-state mRNA levels of cbh1 being the highest. Solka floc cellulose and the disaccharide sophorose induced expression to almost the same level. Moderate expression was observed when cellobiose or lactose was used as the carbon source. It was found that glycerol and sorbitol do not promote expression but, unlike glucose, do not inhibit it either, because the addition of 1 to 2 mM sophorose to glycerol or sorbitol cultures provokes high cellulase expression levels. These carbon sources thus provide a useful means to study cellulase regulation without significantly affecting the growth of the fungus. RNA slot blot experiments showed that no expression could be observed on glucose-containing medium and that high glucose levels abolish the inducing effect of sophorose. The results clearly show that distinct and clear-cut mechanisms of induction and glucose repression regulate cellulase expression in an actively growing fungus. However, derepression of cellulase expression occurs without apparent addition of an inducer once glucose has been depleted from the medium. This expression seems not to arise simply from starvation, since the lack of carbon or nitrogen as such is not sufficient to trigger significant expression.
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Affiliation(s)
- M Ilmén
- VTT Biotechnology and Food Research, Espoo, Finland
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32
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Kuhad RC, Singh A, Eriksson KE. Microorganisms and enzymes involved in the degradation of plant fiber cell walls. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 1997; 57:45-125. [PMID: 9204751 DOI: 10.1007/bfb0102072] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
One of natures most important biological processes is the degradation of lignocellulosic materials to carbon dioxide, water and humic substances. This implies possibilities to use biotechnology in the pulp and paper industry and consequently, the use of microorganisms and their enzymes to replace or supplement chemical methods is gaining interest. This chapter describes the structure of wood and the main wood components, cellulose, hemicelluloses and lignins. The enzyme and enzyme mechanisms used by fungi and bacteria to modify and degrade these components are described in detail. Techniques for how to assay for these enzyme activities are also described. The possibilities for biotechnology in the pulp and paper industry and other fiber utilizing industries based on these enzymes are discussed.
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Affiliation(s)
- R C Kuhad
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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Morikawa Y, Ohashi T, Mantani O, Okada H. Cellulase induction by lactose in Trichoderma reesei PC-3-7. Appl Microbiol Biotechnol 1995. [DOI: 10.1007/bf00164488] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sugden C, Bhat MK. Cereal straw and pure cellulose as carbon sources for growth and production of plant cell-wall degrading enzymes by Sporotrichum thermophile. World J Microbiol Biotechnol 1994; 10:444-51. [DOI: 10.1007/bf00144470] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 02/16/1994] [Accepted: 03/01/1994] [Indexed: 11/29/2022]
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Defaye J, Guillot JM. A convenient synthesis for anomeric 2-thioglucobioses, 2-thiokojibiose and 2-thiosophorose. Carbohydr Res 1994; 253:185-94. [PMID: 8156547 DOI: 10.1016/0008-6215(94)80064-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
2-S-alpha-D-Glucopyranosyl-2-thio-D-glucopyranose (2-thiokojibiose, 8) and 2-S-beta-D-glucopyranosyl-2-thio-D-glucopyranose (2-thiosophorose, 14) were conveniently prepared by SN2 reaction of the corresponding anomers of 2,3,4,6-tetra-O-acetyl-1-thio-D-glucopyranose with 1,3,4,6-tetra-O-acetyl-2-O-tri-flyl-beta-D-mannopyranose, followed by a deprotection sequence for the anomeric acetate involving conversion into the 1-propenyl glycosides. Alkaline O-deacetylation was followed by smooth hydrolysis of the propenyl group at pH approximately 2.
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Affiliation(s)
- J Defaye
- CNRS, Département de Recherche Fondamentale sur la Matière Condensée/SESAM, Centre d'Etudes de Grenoble, France
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Triggering of cellulase biosynthesis by cellulose in Trichoderma reesei. Involvement of a constitutive, sophorose-inducible, glucose-inhibited beta-diglucoside permease. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)36523-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
A 613-bp fragment of the 5' upstream region of the Trichoderma reesei cbh2 gene (coding for the cellulolytic enzyme cellobiohydrolase II) has been isolated and sequenced. Fusion of this fragment to the E. coli uidA gene (coding for beta-glucuronidase) leads to--albeit low--expression of beta-glucuronidase activity in the presence of cellulose and upon the addition of low molecular weight inducers (sophorose, lactose) of cellobiohydrolase II. It also governed the formation of beta-glucuronidase activity during sporulation and its transport to the conidial surface. However, despite the presence of a signal peptide in the cbh2:uidA fusion, beta-glucuronidase was not secreted in T. reesei. Defined fragments of the 613-bp promoter region were isolated and used to identify areas involved in the regulation of cbh2 expression by protein-DNA binding assays. At least two binding areas--between -443/-363 and -363/-173, respectively--were identified. In both areas, the DNA-protein complex observed was appreciably larger when cell-free extracts from sophorose-induced mycelia were used. This suggests that at least one of the proteins regulating cbh2 transcription is itself induced by cellulose.
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Affiliation(s)
- H Stangl
- Abteilung für Mikrobielle Biochemie, Institut für Biochemische Technologie und Mikrobiologie, Wien, Austria
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Regulatory aspects of endoglucanase production by the brown-rot fungusGloeophyllum trabeum. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0147-5975(92)90001-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Riou C, Fraissinet-Tachet L, Freyssinet G, Fèvre M. Secretion of pectic isoenzymes bySclerotinia sclerotiorum. FEMS Microbiol Lett 1992. [DOI: 10.1111/j.1574-6968.1992.tb05214.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Riou C, Freyssinet G, Fevre M. Purification and Characterization of Extracellular Pectinolytic Enzymes Produced by
Sclerotinia sclerotiorum. Appl Environ Microbiol 1992; 58:578-83. [PMID: 16348646 PMCID: PMC195287 DOI: 10.1128/aem.58.2.578-583.1992] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An exopolygalacturonase (exoPG) and an exopolymethylgalacturonase (exoPMG) produced by
Sclerotinia sclerotiorum
have been purified by ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. The exoPG and the exoPMG were purified 66- and 50-fold, respectively, by using a series of separation procedures that included ammonium sulfate precipitation and gel chromatography. Molecular masses of the native proteins were 68 kDa for exoPG and 140 kDa for exoPMG. The pH optima of the enzymes were about pH 5, and their optimum temperature was 45°C. Activities of both enzymes were inhibited by Hg
2+
, Zn
2+
, Cu
2+
, and
p
-chloromercuribenzoate. ExoPMG activity, in contrast to exoPG activity, was stimulated by Mn
2+
and Co
2+
. ExoPMG hydrolyzed only citrus pectin, while exoPG degraded sodium polygalacturonate and, to a lesser extent, citrus pectin. The exo mode of action of the enzymes was revealed by thin-layer chromatography of substrate hydrolysates. Antibodies raised against each purified protein exhibited no cross-reaction, thus confirming the biochemical specificities of the enzymes.
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Affiliation(s)
- C Riou
- Laboratoire de Biologie Cellulaire Fongique, CGMC, UMR Centre National de la Recherche Scientifique 106, Université Lyon I (Bâtiment 405), 43, Boulevard 11 Novembre 1918, 69622 Villeurbanne Cedex, and Rhône-Poulenc Agrochimie, Service de Biologie Moléculaire et Cellulaire Végétale, 69263 Lyon Cedex 09, France
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