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Adnan M, Liu G. Promoters and Synthetic Promoters in Trichoderma reesei. Methods Mol Biol 2024; 2844:47-68. [PMID: 39068331 DOI: 10.1007/978-1-0716-4063-0_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Trichoderma reesei holds immense promise for large-scale protein production, rendering it an excellent subject for deeper exploration using genetic engineering methods to achieve a comprehensive grasp of its cellular physiology. Understanding the genetic factors governing its intrinsic regulatory network is crucial, as lacking this knowledge could impede the expression of target genes. Prior and ongoing studies have concentrated on advancing new expression systems grounded in synthetic biology principles. These methodologies involve utilizing established potent promoters or engineered variations. Genomic and transcriptomic analyses have played a pivotal role in identifying robust promoters and expression systems, including light-responsive, copper-inducible, L-methionine-inducible, and Tet-On systems, among others. This chapter seeks to highlight various research endeavors focusing on tunable and constitutive promoters, the impact of different promoters on both native and foreign protein expression, the discovery of fresh promoters, and strategies conducive to future research aimed at refining and enhancing protein expression in T. reesei. Characterizing new promoters and adopting innovative expression systems hold the potential to significantly expand the molecular toolkit accessible for genetically engineering T. reesei strains. For instance, modifying potent inducible promoters such as Pcbh1 by replacing transcriptional repressors (cre1, ace1) with activators (xyr1, ace2, ace3, hap2/3/5) and integrating synthetic expression systems can result in increased production of crucial enzymes such as endoglucanases (EGLs), β-glucosidases (BGLs), and cellobiohydrolases (CBHs). Similarly, robust constitutive promoters such as Pcdna1 can be converted into synthetic hybrid promoters by incorporating activation elements from potent inducible promoters, facilitating cellulase induction and expression even under repressive conditions. Nevertheless, further efforts are necessary to uncover innovative promoters and devise novel expression strategies to enhance the production of desired proteins on an industrial scale.
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Affiliation(s)
- Muhammad Adnan
- Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Gang Liu
- Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
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Luu XC, Shida Y, Suzuki Y, Kuwahara D, Fujimoto T, Takahashi Y, Sato N, Nakamura A, Ogasawara W. Ultrahigh-throughput screening of Trichoderma reesei strains capable of carbon catabolite repression release and cellulase hyperproduction using a microfluidic droplet platform. Biosci Biotechnol Biochem 2023; 87:1393-1406. [PMID: 37550222 DOI: 10.1093/bbb/zbad108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/28/2023] [Indexed: 08/09/2023]
Abstract
Trichoderma reesei is the most well-known cellulase producer in the biorefinery industry. Its cellulase biosynthesis is repressed by glucose via carbon catabolite repression (CCR), making CCR-releasing strains with cellulase hyperproduction desirable. Here, we employed a microfluidic droplet platform to culture and screen T. reesei mutants capable of CCR release and cellulase overproduction from extensive mutagenesis libraries. With 3 mutagenesis rounds, about 6.20 × 103 droplets were sorted from a population of 1.51 × 106 droplets in a period of 4.4 h; 76 recovery mutants were screened on flask fermentation, and 2 glucose uptake retarded mutants, MG-9-3 and MG-9-3-30, were eventually isolated. We also generated a hypercellulase producer, M-5, with CCR release via a single mutagenesis round. The hyphal morphology and molecular mechanisms in the mutants were analyzed. This versatile approach combined with a comprehensive understanding of CCR release mechanisms will provide innovative and effective strategies for low-cost cellulase production.
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Affiliation(s)
- Xuan Chinh Luu
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yosuke Shida
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yoshiyuki Suzuki
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Daiki Kuwahara
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Takeshi Fujimoto
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yuka Takahashi
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Naomi Sato
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Akihiro Nakamura
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Wataru Ogasawara
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
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Dong CD, Patel AK, Madhavan A, Chen CW, Singhania RR. Significance of glycans in cellulolytic enzymes for lignocellulosic biorefinery - A review. BIORESOURCE TECHNOLOGY 2023; 379:128992. [PMID: 37011847 DOI: 10.1016/j.biortech.2023.128992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 05/03/2023]
Abstract
Lignocellulosic (LC) biomass is the most abundant renewable resource for mankind gravitating society towards sustainable solution for energy that can reduce the carbon footprint. The economic feasibility of 'biomass biorefinery' depends upon the efficiency cellulolytic enzymes which is the main crux. Its high production cost and low efficiencies are the major limitations, that need to be resolved. As the complexity of the genome increases, so does the complexity of the proteome, further facilitated by protein post-translational modifications (PTMs). Glycosylation is regarded the major PTMs and hardly any recent work is focused on importance of glycosylation in cellulase. By modifying protein side chains and glycans, superior cellulases with improved stability and efficiency can be obtained. Functional proteomics relies heavily on PTMs because they regulate activity, localization, and interactions with protein, lipid, nucleic acid, and cofactor molecules. O- and N- glycosylation in cellulases influences its characteristics adding positive attributes to the enzymes.
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Affiliation(s)
- Cheng-Di Dong
- Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan; Sustainable Environment Research Center, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan
| | - Anil Kumar Patel
- Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow 226 029, India
| | - Aravind Madhavan
- School of Biotechnology, Amrita Vishwa Vidyapeetham, Amritapuri, Kollam, Kerala 690 525, India
| | - Chiu-Wen Chen
- Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan; Sustainable Environment Research Center, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan
| | - Reeta Rani Singhania
- Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow 226 029, India.
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Li N, Qiu Z, Cai W, Shen Y, Wei D, Chen Y, Wang W. The Ras small GTPase RSR1 regulates cellulase production in Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:87. [PMID: 37218014 DOI: 10.1186/s13068-023-02341-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 05/13/2023] [Indexed: 05/24/2023]
Abstract
BACKGROUND Lignocellulose is the most abundant renewable resource in the world and has attracted widespread attention. It can be hydrolyzed into sugars with the help of cellulases and hemicellulases that are secreted by filamentous fungi. Several studies have revealed that the Ras small GTPase superfamily regulates important cellular physiological processes, including synthesis of metabolites, sporulation, and cell growth and differentiation. However, it remains unknown how and to what extent Ras small GTPases participate in cellulase production. RESULTS In this study, we found that the putative Ras small GTPase RSR1 negatively regulated the expression of cellulases and xylanases. Deletion of rsr1 (∆rsr1) significantly increased cellulase production and decreased the expression levels of ACY1-cAMP-protein kinase A (PKA) signaling pathway genes and the concentration of intracellular cyclic adenosine monophosphate (cAMP). Loss of acy1 based on ∆rsr1 (∆rsr1∆acy1) could further increase cellulase production and the expression levels of cellulase genes, while overexpression of acy1 based on ∆rsr1 (∆rsr1-OEacy1) significantly reduced cellulase production and transcriptional levels of cellulase genes. In addition, our results revealed that RSR1 negatively controlled cellulase production via the ACY1-cAMP-PKA pathway. Transcriptome analysis revealed significantly increased expression of three G-protein coupled receptors (GPCRs; tre62462, tre58767, and tre53238) and approximately two-fold higher expression of ACE3 and XYR1, which transcriptionally activated cellulases with the loss of rsr1. ∆rsr1∆ tre62462 exhibited a decrease in cellulase activity compared to ∆rsr1, while that of ∆rsr1∆tre58767 and ∆rsr1∆tre53238 showed a remarkable improvement compared to ∆rsr1. These findings revealed that GPCRs on the membrane may sense extracellular signals and transmit them to rsr1 and then to ACY1-cAMP-PKA, thereby negatively controlling the expression of the cellulase activators ACE3 and XYR1. These data indicate the crucial role of Ras small GTPases in regulating cellulase gene expression. CONCLUSIONS Here, we demonstrate that some GPCRs and Ras small GTPases play key roles in the regulation of cellulase genes in Trichoderma reesei. Understanding the roles of these components in the regulation of cellulase gene transcription and the signaling processes in T. reesei can lay the groundwork for understanding and transforming other filamentous fungi.
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Affiliation(s)
- Ni Li
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Zhouyuan Qiu
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Wanchuan Cai
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Yaling Shen
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Dongzhi Wei
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Yumeng Chen
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Wei Wang
- The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China.
- Jiangsu Yiming Biological Technology Co., Ltd., Suqian, 223699, Jiangsu, China.
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Ma C, Liu J, Tang J, Sun Y, Jiang X, Zhang T, Feng Y, Liu Q, Wang L. Current genetic strategies to investigate gene functions in Trichoderma reesei. Microb Cell Fact 2023; 22:97. [PMID: 37161391 PMCID: PMC10170752 DOI: 10.1186/s12934-023-02104-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 04/21/2023] [Indexed: 05/11/2023] Open
Abstract
The filamentous fungus Trichoderma reesei (teleomorph Hypocrea jecorina, Ascomycota) is a well-known lignocellulolytic enzymes-producing strain in industry. To increase the fermentation titer of lignocellulolytic enzymes, random mutagenesis and rational genetic engineering in T. reesei were carried out since it was initially found in the Solomon Islands during the Second World War. Especially the continuous exploration of the underlying regulatory network during (hemi)cellulase gene expression in the post-genome era provided various strategies to develop an efficient fungal cell factory for these enzymes' production. Meanwhile, T. reesei emerges competitiveness potential as a filamentous fungal chassis to produce proteins from other species (e.g., human albumin and interferon α-2b, SARS-CoV-2 N antigen) in virtue of the excellent expression and secretion system acquired during the studies about (hemi)cellulase production. However, all the achievements in high yield of (hemi)cellulases are impossible to finish without high-efficiency genetic strategies to analyze the proper functions of those genes involved in (hemi)cellulase gene expression or secretion. Here, we in detail summarize the current strategies employed to investigate gene functions in T. reesei. These strategies are supposed to be beneficial for extending the potential of T. reesei in prospective strain engineering.
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Affiliation(s)
- Chixiang Ma
- China Medical University-The Queen's University of Belfast Joint College, Shenyang, Liaoning, 110122, China
| | - Jialong Liu
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Jiaxin Tang
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Yuanlu Sun
- China Medical University-The Queen's University of Belfast Joint College, Shenyang, Liaoning, 110122, China
| | - Xiaojie Jiang
- China Medical University-The Queen's University of Belfast Joint College, Shenyang, Liaoning, 110122, China
| | - Tongtong Zhang
- China Medical University-The Queen's University of Belfast Joint College, Shenyang, Liaoning, 110122, China
| | - Yan Feng
- College of Life Sciences, Shanxi Agricultural University, Jinzhong, 030801, Shanxi, China
| | - Qinghua Liu
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Lei Wang
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
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Arai T, Ichinose S, Shibata N, Kakeshita H, Kodama H, Igarashi K, Takimura Y. Inducer-free cellulase production system based on the constitutive expression of mutated XYR1 and ACE3 in the industrial fungus Trichoderma reesei. Sci Rep 2022; 12:19445. [PMID: 36376415 PMCID: PMC9663580 DOI: 10.1038/s41598-022-23815-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
Trichoderma reesei is a widely used host for producing cellulase and hemicellulase cocktails for lignocellulosic biomass degradation. Here, we report a genetic modification strategy for industrial T. reesei that enables enzyme production using simple glucose without inducers, such as cellulose, lactose and sophorose. Previously, the mutated XYR1V821F or XYR1A824V was known to induce xylanase and cellulase using only glucose as a carbon source, but its enzyme composition was biased toward xylanases, and its performance was insufficient to degrade lignocellulose efficiently. Therefore, we examined combinations of mutated XYR1V821F and constitutively expressed CRT1, BGLR, VIB1, ACE2, or ACE3, known as cellulase regulators and essential factors for cellulase expression to the T. reesei E1AB1 strain that has been highly mutagenized for improving enzyme productivity and expressing a ß-glucosidase for high enzyme performance. The results showed that expression of ACE3 to the mutated XYR1V821F expressing strain promoted cellulase expression. Furthermore, co-expression of these two transcription factors also resulted in increased productivity, with enzyme productivity 1.5-fold higher than with the conventional single expression of mutated XYR1V821F. Additionally, that productivity was 5.5-fold higher compared to productivity with an enhanced single expression of ACE3. Moreover, although the DNA-binding domain of ACE3 had been considered essential for inducer-free cellulase production, we found that ACE3 with a partially truncated DNA-binding domain was more effective in cellulase production when co-expressed with a mutated XYR1V821F. This study demonstrates that co-expression of the two transcription factors, the mutated XYR1V821F or XYR1A824V and ACE3, resulted in optimized enzyme composition and increased productivity.
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Affiliation(s)
- Toshiharu Arai
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Sakurako Ichinose
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Nozomu Shibata
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Hiroshi Kakeshita
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan.
| | - Hiroshi Kodama
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Kazuaki Igarashi
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Yasushi Takimura
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
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Luo X, Li R, Feng JX, Qin X. Disruption of vacuolar protein sorting receptor gene Poxvps10 improves cellulolytic enzyme production by Penicillium oxalicum. Enzyme Microb Technol 2022; 160:110098. [PMID: 35863188 DOI: 10.1016/j.enzmictec.2022.110098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/26/2022] [Accepted: 07/13/2022] [Indexed: 11/03/2022]
Abstract
Penicillium oxalicum can secrete numerous of plant biomass-degrading enzymes, but limited information is available regarding the mechanisms associated with their secretion. In the Golgi-to-vacuole pathway, the type I transmembrane receptor Vps10p is involved in the sorting of the soluble vacuolar proteins and can also target recombinant and aberrant proteins from the Golgi to the vacuole for degradation. Here, we used the combination of phenotypic characterization and comparative secretome analysis to explore the effect of disruption of the vps10 gene in P. oxalicum (Poxvps10) on endogenous cellulolytic enzyme secretion. The study found that PoxVps10p is required for the targeting and delivery of vacuolar PoxCpyA to the vacuole in P. oxalicum. Poxvps10p deletion enhances extracellular protein and cellulase production by P. oxalicum when the cells are grown on a cellulosic substrate (wheat bran and Avicel). Furthermore, secretome analysis revealed higher relative amount of cellulases, lytic polysaccharide monooxygenase and post-translational modification-related proteins in the ΔPoxvps10 mutant than in the wild-type (WT) strain, which may explain the higher cellulase production by the ΔPoxvps10 than the WT strain. This study thus provides a new target for manipulating the secretory pathway to enhance the cellulolytic enzyme production.
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Affiliation(s)
- Xiang Luo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Ruijie Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Jia-Xun Feng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Xiulin Qin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China.
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Characterization of Cellulose-Degrading Bacteria Isolated from Soil and the Optimization of Their Culture Conditions for Cellulase Production. Appl Biochem Biotechnol 2022; 194:5060-5082. [PMID: 35687308 DOI: 10.1007/s12010-022-04002-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2022] [Indexed: 11/02/2022]
Abstract
The characterization of bacteria with hydrolytic potential significantly contributes to the industries. Six cellulose-degrading bacteria were isolated from mixture soil samples collected at Kingfisher Lake and the University of Manitoba campus by Congo red method using carboxymethyl cellulose agar medium and identified as Paenarthrobacter sp. MKAL1, Hymenobacter sp. MKAL2, Mycobacterium sp. MKAL3, Stenotrophomonas sp. MKAL4, Chryseobacterium sp. MKAL5, and Bacillus sp. MKAL6. Their cellulase production was optimized by controlling different environmental and nutritional factors such as pH, temperature, incubation period, substrate concentration, nitrogen, and carbon sources using the dinitrosalicylic acid and response surface methods. Except for Paenarthrobacter sp. MKAL1, all strains are motile. Only Bacillus sp. MKAL6 was non-salt-tolerant and showed gelatinase activity. Sucrose enhanced higher cellulase activity of 78.87 ± 4.71 to 190.30 ± 6.42 U/mL in these strains at their optimum pH (5-6) and temperature (35-40 °C). The molecular weights of these cellulases were about 25 kDa. These bacterial strains could be promising biocatalysts for converting cellulose into glucose for industrial purposes.
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Mattam AJ, Chaudhari YB, Velankar HR. Factors regulating cellulolytic gene expression in filamentous fungi: an overview. Microb Cell Fact 2022; 21:44. [PMID: 35317826 PMCID: PMC8939176 DOI: 10.1186/s12934-022-01764-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 02/27/2022] [Indexed: 12/19/2022] Open
Abstract
The growing demand for biofuels such as bioethanol has led to the need for identifying alternative feedstock instead of conventional substrates like molasses, etc. Lignocellulosic biomass is a relatively inexpensive feedstock that is available in abundance, however, its conversion to bioethanol involves a multistep process with different unit operations such as size reduction, pretreatment, saccharification, fermentation, distillation, etc. The saccharification or enzymatic hydrolysis of cellulose to glucose involves a complex family of enzymes called cellulases that are usually fungal in origin. Cellulose hydrolysis requires the synergistic action of several classes of enzymes, and achieving the optimum secretion of these simultaneously remains a challenge. The expression of fungal cellulases is controlled by an intricate network of transcription factors and sugar transporters. Several genetic engineering efforts have been undertaken to modulate the expression of cellulolytic genes, as well as their regulators. This review, therefore, focuses on the molecular mechanism of action of these transcription factors and their effect on the expression of cellulases and hemicellulases.
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Affiliation(s)
- Anu Jose Mattam
- Hindustan Petroleum Green R and D Centre (HPGRDC), KIADB Industrial Area, Tarabanahalli, Devanagundi, Hoskote, Bangalore, 560067, India
| | - Yogesh Babasaheb Chaudhari
- Hindustan Petroleum Green R and D Centre (HPGRDC), KIADB Industrial Area, Tarabanahalli, Devanagundi, Hoskote, Bangalore, 560067, India
| | - Harshad Ravindra Velankar
- Hindustan Petroleum Green R and D Centre (HPGRDC), KIADB Industrial Area, Tarabanahalli, Devanagundi, Hoskote, Bangalore, 560067, India.
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10
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Promoter regulation and genetic engineering strategies for enhanced cellulase expression in Trichoderma reesei. Microbiol Res 2022; 259:127011. [DOI: 10.1016/j.micres.2022.127011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 01/18/2023]
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11
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Xu W, Fang Y, Ding M, Ren Y, Meng X, Chen G, Zhang W, Liu W. Elimination of the Sugar Transporter GAT1 Increased Xylanase I Production in Trichoderma reesei. Front Microbiol 2022; 13:810066. [PMID: 35154055 PMCID: PMC8825865 DOI: 10.3389/fmicb.2022.810066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 01/04/2022] [Indexed: 11/17/2022] Open
Abstract
The filamentous fungus Trichoderma reesei secretes large quantities of cellulases and hemicellulases that have found wide applications in industry. Compared with extensive studies on the mechanism controlling cellulase gene expression, less is known about the regulatory mechanism behind xylanase gene expression. Herein, several putative sugar transporter encoding genes that showed significant upregulation on xylan were identified in T. reesei. Deletion of one such gene, gat1, resulted in increased xylanase production but hardly affected cellulase induction. Further analyses demonstrated that deletion of gat1 markedly increased XYNI production at the transcriptional level and only exerted a minor effect on XYNII synthesis. In contrast, overexpressing gat1 caused a continuous decrease in xyn1 expression. Deletion of gat1 also affected the expression of xyn1 and pectinase genes when T. reesei was cultivated with galacturonic acid as the sole carbon source. Transcriptome analyses of Δgat1 and its parental strain identified 255 differentially expressed genes that are enriched in categories of glycoside hydrolases, lipid metabolism, transporters, and transcriptional factors. The results thus implicate a repressive role of the sugar transporter GAT1 in xyn1 expression and reveal that distinct regulatory mechanisms may exist in controlling the expression of different xylanase genes in T. reesei.
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Affiliation(s)
- Wenqiang Xu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yu Fang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Mingyang Ding
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yajing Ren
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
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Zhang W, Guo J, Wu X, Ren Y, Li C, Meng X, Liu W. Reformulating the Hydrolytic Enzyme Cocktail of Trichoderma reesei by Combining XYR1 Overexpression and Elimination of Four Major Cellulases to Improve Saccharification of Corn Fiber. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:211-222. [PMID: 34935374 DOI: 10.1021/acs.jafc.1c05946] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The industrial fungus Trichoderma reesei has an outstanding capability of secreting an enzyme cocktail comprising multiple plant biomass-degrading enzymes. Herein, the overexpression of XYR1, the master transactivator controlling (hemi)cellulase gene expression, was performed in T. reesei lacking four main cellulase-encoding genes. The resultant strain Δ4celOExyr1 was able to produce a dramatically different profile of secretory proteins on soluble glucose or lactose compared with that of the wild-type T. reesei. The Δ4celOExyr1 secretome included cellulases EGIII and BGLI as well as several hemicellulases and nonhydrolytic cellulose degradation-associated proteins that are not preferentially induced in the wild-type T. reesei strain. Δ4celOExyr1 produced a significant amount of α-arabinofuranosidase I on lactose, and the crude enzyme cocktail of Δ4celOExyr1 not only released a considerable quantity of glucose but also exhibited remarkable performance in the hydrolytic release of xylose, arabinose, and mannose from un-pretreated corn fiber. These results showed that the engineered T. reesei strain holds great potential for improving the saccharification efficiency of the hemicellulosic constituents within corn fiber.
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Affiliation(s)
- Weixin Zhang
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Junqi Guo
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Xiaoxiao Wu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Yajing Ren
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Chunyan Li
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, P. R. China
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Liu Y, Tang Y, Gao H, Zhang W, Jiang Y, Xin F, Jiang M. Challenges and Future Perspectives of Promising Biotechnologies for Lignocellulosic Biorefinery. Molecules 2021; 26:5411. [PMID: 34500844 PMCID: PMC8433869 DOI: 10.3390/molecules26175411] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/23/2021] [Accepted: 08/31/2021] [Indexed: 02/07/2023] Open
Abstract
Lignocellulose is a kind of renewable bioresource containing abundant polysaccharides, which can be used for biochemicals and biofuels production. However, the complex structure hinders the final efficiency of lignocellulosic biorefinery. This review comprehensively summarizes the hydrolases and typical microorganisms for lignocellulosic degradation. Moreover, the commonly used bioprocesses for lignocellulosic biorefinery are also discussed, including separated hydrolysis and fermentation, simultaneous saccharification and fermentation and consolidated bioprocessing. Among these methods, construction of microbial co-culturing systems via consolidated bioprocessing is regarded as a potential strategy to efficiently produce biochemicals and biofuels, providing theoretical direction for constructing efficient and stable biorefinery process system in the future.
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Affiliation(s)
- Yansong Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
| | - Yunhan Tang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
| | - Haiyan Gao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China; (Y.L.); (Y.T.); (H.G.); (W.Z.); (M.J.)
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, China
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14
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Cellulases, Hemicellulases, and Pectinases: Applications in the Food and Beverage Industry. FOOD BIOPROCESS TECH 2021. [DOI: 10.1007/s11947-021-02678-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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15
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Sukumaran RK, Christopher M, Kooloth-Valappil P, Sreeja-Raju A, Mathew RM, Sankar M, Puthiyamadam A, Adarsh VP, Aswathi A, Rebinro V, Abraham A, Pandey A. Addressing challenges in production of cellulases for biomass hydrolysis: Targeted interventions into the genetics of cellulase producing fungi. BIORESOURCE TECHNOLOGY 2021; 329:124746. [PMID: 33610429 DOI: 10.1016/j.biortech.2021.124746] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
Lignocellulosic materials are the favoured feedstock for biorefineries due to their abundant availability and non-completion with food. Biobased technologies for refining these materials are limited mainly by the cost of biomass hydrolyzing enzymes, typically sourced from filamentous fungi. Therefore, considerable efforts have been directed at improving the quantity and quality of secreted lignocellulose degrading enzymes from fungi in order to attain overall economic viability. Process improvements and media engineering probably have reached their thresholds and further production enhancements require modifying the fungal metabolism to improve production and secretion of these enzymes. This review focusses on the types and mechanisms of action of known fungal biomass degrading enzymes, our current understanding of the genetic control exerted on their expression, and possible routes for intervention, especially on modulating catabolite repression, transcriptional regulators, signal transduction, secretion pathways etc., in order to improve enzyme productivity, activity and stability.
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Affiliation(s)
- Rajeev K Sukumaran
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India.
| | - Meera Christopher
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Prajeesh Kooloth-Valappil
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - AthiraRaj Sreeja-Raju
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Reshma M Mathew
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Meena Sankar
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Anoop Puthiyamadam
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Velayudhanpillai-Prasannakumari Adarsh
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Aswathi Aswathi
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Valan Rebinro
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Ashok Pandey
- Centre for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow, India
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16
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Najjarzadeh N, Matsakas L, Rova U, Christakopoulos P. How Carbon Source and Degree of Oligosaccharide Polymerization Affect Production of Cellulase-Degrading Enzymes by Fusarium oxysporum f. sp. lycopersici. Front Microbiol 2021; 12:652655. [PMID: 33841380 PMCID: PMC8032549 DOI: 10.3389/fmicb.2021.652655] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
Cellulases are a group of enzymes responsible for the degradation of cellulose, which is one of the most abundant polymers on Earth. The three main groups of cellulases are endoglucosidases, exoglucosidases, and β-glucosidases; however, the mechanism of induction of these enzymes remains poorly characterized. Cellooligosaccharides are among the main inducers of these enzymes in filamentous fungi, yet it is not clear how their degree of polymerization may affect the strength of induction. In the present study, we investigated the effect of different carbohydrate-based inducers, such as lactose, sophorose, cellooligosaccharides, and xylooligosacharides, characterized by different concentrations and degree of polymerization, on cellulases production by the fungus Fusarium oxysporum f. sp. lycopersici, which is one of the most studied lignocellulose degrading fungi with the ability to consume both cellulose and hemicellulose. Moreover, the effect of carbon source on cellulase induction was assessed by growing the biomass on sucrose or glycerol. Results showed a correlation between induction efficiency and the cellooligosaccharides' concentration and size, as well as the carbon source available. Specifically, cellotetraose was a better inducer when sucrose was the carbon source, while cellobiose yielded a better result on glycerol. These findings can help optimize industrial cellulase production.
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Affiliation(s)
| | | | | | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
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17
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Daranagama ND, Suzuki Y, Shida Y, Ogasawara W. Involvement of Xyr1 and Are1 for Trichodermapepsin Gene Expression in Response to Cellulose and Galactose in Trichoderma reesei. Curr Microbiol 2020; 77:1506-1517. [DOI: 10.1007/s00284-020-01955-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 03/18/2020] [Indexed: 10/24/2022]
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18
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Okal EJ, Aslam MM, Karanja JK, Nyimbo WJ. Mini review: Advances in understanding regulation of cellulase enzyme in white-rot basidiomycetes. Microb Pathog 2020; 147:104410. [PMID: 32707312 DOI: 10.1016/j.micpath.2020.104410] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/14/2020] [Accepted: 07/17/2020] [Indexed: 12/17/2022]
Abstract
White-rot basidiomycetic fungi have gained a lot of scientific attention in recent years owing to their ability to produce cellulase enzymes that are of great importance in numerous industrial applications. This has seen a rise in number of studies seeking to comprehend both physical and molecular mechanisms that regulate the production of cellulase enzymes in these fungi. Cellulase has several applications in production of food and beverages, biofuel, biological detergents, pharmaceuticals, and deinking in paper and pulp industry. Enhanced understanding of genetic mechanisms that regulate cellulase production would have utility for optimal cellulase production in white-rot basidiomycetes using biotechnology approaches. Carbon catabolite repression and various transcriptional factors such as XlnR, Cre, Clr, Ace, and gna1 control expression of genes encoding cellobiohydrolase (CBH), endoglucanase (EGL) and β-glucosidase (BGL). In this review, we have consolidated and summarised some of recent findings on genetic regulation of cellulase with an aim of highlighting the general regulatory mechanisms that underlie cellulase expressions in white-rot fungi. This review further outlines some of important transcription factors that regulate cellulase genes, and key research gaps that may need to be addressed by future research.
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Affiliation(s)
- Eyalira J Okal
- Juncao Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
| | - Mehtab Muhammad Aslam
- Center for Plant Water-Use and Nutrition Regulation, College of Life Sciences, Joint International Research Laboratory of Water and Nutrient in Cops, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Joseph K Karanja
- Center for Plant Water-Use and Nutrition Regulation, College of Life Sciences, Joint International Research Laboratory of Water and Nutrient in Cops, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Witness J Nyimbo
- Juncao Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
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19
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Meng QS, Zhang F, Liu CG, Zhao XQ, Bai FW. Identification of a novel repressor encoded by the putative gene ctf1 for cellulase biosynthesis in Trichoderma reesei through artificial zinc finger engineering. Biotechnol Bioeng 2020; 117:1747-1760. [PMID: 32124970 DOI: 10.1002/bit.27321] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/28/2020] [Accepted: 03/01/2020] [Indexed: 11/09/2022]
Abstract
Strains from Trichoderma reesei have been used for cellulase production with a long history. It has been well known that cellulase biosynthesis by the fungal species is controlled through regulators, and elucidation of their regulation network is of great importance for engineering T. reesei with robust cellulase production. However, progress in this regard is still very limited. In this study, T. reesei RUT-C30 was transformed with an artificial zinc finger protein (AZFP) library, and the mutant T. reesei M2 with improved cellulase production was screened. Compared to its parent strain, the filter paper activity and endo-β-glucanase activity in cellulases produced by T. reesei M2 increased 67.2% and 35.3%, respectively. Analysis by quantitative reverse transcription polymerase chain reaction indicated significant downregulation of the putative gene ctf1 in T. reesei M2, and its deletion mutants were thus developed for further studies. An increase of 36.9% in cellulase production was observed in the deletion mutants, but when ctf1 was constitutively overexpressed in T. reesei RUT-C30 under the control of the strong pdc1 promoter, cellulase production was substantially compromised. Comparative transcriptomic analysis revealed that the deletion of ctf1 upregulated transcription of gene encoding the regulator VIB1, but downregulated transcription of gene encoding another regulator RCE1, which consequently upregulated genes encoding the transcription factors XYR1 and ACE3 for the activation of genes encoding cellulolytic enzymes. As a result, ctf1 was characterized as a gene encoding a repressor for cellulase production in T. reesei RUT-C30, which is significant for further elucidating molecular mechanism underlying cellulase biosynthesis by the fungal species for rational design to develop robust strains for cellulase production. And in the meantime, AZFP transformation was validated to be an effective strategy for identifying functions of putative genes in the genome of T. reesei.
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Affiliation(s)
- Qing-Shan Meng
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Science, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Science, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Chen-Guang Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Science, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Science, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Feng-Wu Bai
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Science, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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20
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Wang BT, Hu S, Yu XY, Jin L, Zhu YJ, Jin FJ. Studies of Cellulose and Starch Utilization and the Regulatory Mechanisms of Related Enzymes in Fungi. Polymers (Basel) 2020; 12:polym12030530. [PMID: 32121667 PMCID: PMC7182937 DOI: 10.3390/polym12030530] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 02/14/2020] [Accepted: 02/16/2020] [Indexed: 12/24/2022] Open
Abstract
Polysaccharides are biopolymers made up of a large number of monosaccharides joined together by glycosidic bonds. Polysaccharides are widely distributed in nature: Some, such as peptidoglycan and cellulose, are the components that make up the cell walls of bacteria and plants, and some, such as starch and glycogen, are used as carbohydrate storage in plants and animals. Fungi exist in a variety of natural environments and can exploit a wide range of carbon sources. They play a crucial role in the global carbon cycle because of their ability to break down plant biomass, which is composed primarily of cell wall polysaccharides, including cellulose, hemicellulose, and pectin. Fungi produce a variety of enzymes that in combination degrade cell wall polysaccharides into different monosaccharides. Starch, the main component of grain, is also a polysaccharide that can be broken down into monosaccharides by fungi. These monosaccharides can be used for energy or as precursors for the biosynthesis of biomolecules through a series of enzymatic reactions. Industrial fermentation by microbes has been widely used to produce traditional foods, beverages, and biofuels from starch and to a lesser extent plant biomass. This review focuses on the degradation and utilization of plant homopolysaccharides, cellulose and starch; summarizes the activities of the enzymes involved and the regulation of the induction of the enzymes in well-studied filamentous fungi.
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21
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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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22
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Villena GK, Kitazono AA, Hernández-Macedo M L. Bioengineering Fungi and Yeast for the Production of Enzymes, Metabolites, and Value-Added Compounds. Fungal Biol 2020. [DOI: 10.1007/978-3-030-41870-0_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Challacombe JF, Hesse CN, Bramer LM, McCue LA, Lipton M, Purvine S, Nicora C, Gallegos-Graves LV, Porras-Alfaro A, Kuske CR. Genomes and secretomes of Ascomycota fungi reveal diverse functions in plant biomass decomposition and pathogenesis. BMC Genomics 2019; 20:976. [PMID: 31830917 PMCID: PMC6909477 DOI: 10.1186/s12864-019-6358-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 12/01/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The dominant fungi in arid grasslands and shrublands are members of the Ascomycota phylum. Ascomycota fungi are important drivers in carbon and nitrogen cycling in arid ecosystems. These fungi play roles in soil stability, plant biomass decomposition, and endophytic interactions with plants. They may also form symbiotic associations with biocrust components or be latent saprotrophs or pathogens that live on plant tissues. However, their functional potential in arid soils, where organic matter, nutrients and water are very low or only periodically available, is poorly characterized. RESULTS Five Ascomycota fungi were isolated from different soil crust microhabitats and rhizosphere soils around the native bunchgrass Pleuraphis jamesii in an arid grassland near Moab, UT, USA. Putative genera were Coniochaeta, isolated from lichen biocrust, Embellisia from cyanobacteria biocrust, Chaetomium from below lichen biocrust, Phoma from a moss microhabitat, and Aspergillus from the soil. The fungi were grown in replicate cultures on different carbon sources (chitin, native bunchgrass or pine wood) relevant to plant biomass and soil carbon sources. Secretomes produced by the fungi on each substrate were characterized. Results demonstrate that these fungi likely interact with primary producers (biocrust or plants) by secreting a wide range of proteins that facilitate symbiotic associations. Each of the fungal isolates secreted enzymes that degrade plant biomass, small secreted effector proteins, and proteins involved in either beneficial plant interactions or virulence. Aspergillus and Phoma expressed more plant biomass degrading enzymes when grown in grass- and pine-containing cultures than in chitin. Coniochaeta and Embellisia expressed similar numbers of these enzymes under all conditions, while Chaetomium secreted more of these enzymes in grass-containing cultures. CONCLUSIONS This study of Ascomycota genomes and secretomes provides important insights about the lifestyles and the roles that Ascomycota fungi likely play in arid grassland, ecosystems. However, the exact nature of those interactions, whether any or all of the isolates are true endophytes, latent saprotrophs or opportunistic phytopathogens, will be the topic of future studies.
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Affiliation(s)
- Jean F Challacombe
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
- Present address: Colorado State University, College of Agricultural Sciences, 301 University Ave, Fort Collins, CO, 80523, USA.
| | - Cedar N Hesse
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
- Horticultural Crops Research, USDA ARS, Corvallis, OR, USA
| | - Lisa M Bramer
- Applied Statistics & Computational Modeling, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Lee Ann McCue
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, 99352, USA
| | - Mary Lipton
- Applied Statistics & Computational Modeling, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Samuel Purvine
- Applied Statistics & Computational Modeling, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Carrie Nicora
- Applied Statistics & Computational Modeling, Pacific Northwest National Laboratory, Richland, Washington, USA
| | | | | | - Cheryl R Kuske
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
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Lin L, Wang S, Li X, He Q, Benz JP, Tian C. STK-12 acts as a transcriptional brake to control the expression of cellulase-encoding genes in Neurospora crassa. PLoS Genet 2019; 15:e1008510. [PMID: 31765390 PMCID: PMC6901240 DOI: 10.1371/journal.pgen.1008510] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/09/2019] [Accepted: 11/05/2019] [Indexed: 12/21/2022] Open
Abstract
Cellulolytic fungi have evolved a complex regulatory network to maintain the precise balance of nutrients required for growth and hydrolytic enzyme production. When fungi are exposed to cellulose, the transcript levels of cellulase genes rapidly increase and then decline. However, the mechanisms underlying this bell-shaped expression pattern are unclear. We systematically screened a protein kinase deletion set in the filamentous fungus Neurospora crassa to search for mutants exhibiting aberrant expression patterns of cellulase genes. We observed that the loss of stk-12 (NCU07378) caused a dramatic increase in cellulase production and an extended period of high transcript abundance of major cellulase genes. These results suggested that stk-12 plays a critical role as a brake to turn down the transcription of cellulase genes to repress the overexpression of hydrolytic enzymes and prevent energy wastage. Transcriptional profiling analyses revealed that cellulase gene expression levels were maintained at high levels for 56 h in the Δstk-12 mutant, compared to only 8 h in the wild-type (WT) strain. After growth on cellulose for 3 days, the transcript levels of cellulase genes in the Δstk-12 mutant were 3.3-fold over WT, and clr-2 (encoding a transcriptional activator) was up-regulated in Δstk-12 while res-1 and rca-1 (encoding two cellulase repressors) were down-regulated. Consequently, total cellulase production in the Δstk-12 mutant was 7-fold higher than in the WT. These results strongly suggest that stk-12 deletion results in dysregulation of the cellulase expression machinery. Further analyses showed that STK-12 directly targets IGO-1 to regulate cellulase production. The TORC1 pathway promoted cellulase production, at least partly, by inhibiting STK-12 function, and STK-12 and CRE-1 functioned in parallel pathways to repress cellulase gene expression. Our results clarify how cellulase genes are repressed at the transcriptional level during cellulose induction, and highlight a new strategy to improve industrial fungal strains.
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Affiliation(s)
- Liangcai Lin
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Shanshan Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xiaolin Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Qun He
- State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - J. Philipp Benz
- Technical University of Munich, TUM School of Life Sciences Weihenstephan, Hans-Carl-von-Carlowitz-Platz, Freising, Germany
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr, Garching, Germany
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- * E-mail:
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25
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Hirasawa H, Shioya K, Mori K, Tashiro K, Aburatani S, Shida Y, Kuhara S, Ogasawara W. Cellulase productivity of Trichoderma reesei mutants developed in Japan varies with varying pH conditions. J Biosci Bioeng 2019; 128:264-273. [DOI: 10.1016/j.jbiosc.2019.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 03/07/2019] [Accepted: 03/09/2019] [Indexed: 01/08/2023]
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26
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Champreda V, Mhuantong W, Lekakarn H, Bunterngsook B, Kanokratana P, Zhao XQ, Zhang F, Inoue H, Fujii T, Eurwilaichitr L. Designing cellulolytic enzyme systems for biorefinery: From nature to application. J Biosci Bioeng 2019; 128:637-654. [PMID: 31204199 DOI: 10.1016/j.jbiosc.2019.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/06/2019] [Accepted: 05/11/2019] [Indexed: 12/14/2022]
Abstract
Cellulolytic enzymes play a key role on conversion of lignocellulosic plant biomass to biofuels and biochemicals in sugar platform biorefineries. In this review, we survey composite carbohydrate-active enzymes (CAZymes) among groups of cellulolytic fungi and bacteria that exist under aerobic and anaerobic conditions. Recent advances in designing effective cellulase mixtures are described, starting from the most complex microbial consortium-based enzyme preparations, to single-origin enzymes derived from intensively studied cellulase producers such as Trichoderma reesei, Talaromyces cellulolyticus, and Penicellium funiculosum, and the simplest minimal enzyme systems comprising selected sets of mono-component enzymes tailor-made for specific lignocellulosic substrates. We provide a comprehensive update on studies in developing high-performance cellulases for biorefineries.
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Affiliation(s)
- Verawat Champreda
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand.
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Hataikarn Lekakarn
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Campus, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Benjarat Bunterngsook
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hiroyuki Inoue
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Tatsuya Fujii
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Lily Eurwilaichitr
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
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27
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de Paula RG, Antoniêto ACC, Ribeiro LFC, Srivastava N, O'Donovan A, Mishra PK, Gupta VK, Silva RN. Engineered microbial host selection for value-added bioproducts from lignocellulose. Biotechnol Adv 2019; 37:107347. [PMID: 30771467 DOI: 10.1016/j.biotechadv.2019.02.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 01/27/2019] [Accepted: 02/08/2019] [Indexed: 12/12/2022]
Abstract
Lignocellulose is a rich and sustainable globally available carbon source and is considered a prominent alternative raw material for producing biofuels and valuable chemical compounds. Enzymatic hydrolysis is one of the crucial steps of lignocellulose degradation. Cellulolytic and hemicellulolytic enzyme mixes produced by different microorganisms including filamentous fungi, yeasts and bacteria, are used to degrade the biomass to liberate monosaccharides and other compounds for fermentation or conversion to value-added products. During biomass pretreatment and degradation, toxic compounds are produced, and undesirable carbon catabolic repression (CCR) can occur. In order to solve this problem, microbial metabolic pathways and transcription factors involved have been investigated along with the application of protein engineering to optimize the biorefinery platform. Engineered Microorganisms have been used to produce specific enzymes to breakdown biomass polymers and metabolize sugars to produce ethanol as well other biochemical compounds. Protein engineering strategies have been used for modifying lignocellulolytic enzymes to overcome enzymatic limitations and improving both their production and functionality. Furthermore, promoters and transcription factors, which are key proteins in this process, are modified to promote microbial gene expression that allows a maximum performance of the hydrolytic enzymes for lignocellulosic degradation. The present review will present a critical discussion and highlight the aspects of the use of microorganisms to convert lignocellulose into value-added bioproduct as well combat the bottlenecks to make the biorefinery platform from lignocellulose attractive to the market.
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Affiliation(s)
- Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Liliane Fraga Costa Ribeiro
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Neha Srivastava
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Anthonia O'Donovan
- School of Science and Computing, Galway-Mayo Institute of Technology, Galway, Ireland
| | - P K Mishra
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Vijai K Gupta
- ERA Chair of Green Chemistry, Department of Chemistry and Biotechnology, Tallinn University of Technology, 12618 Tallinn, Estonia.
| | - Roberto N Silva
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil.
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28
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The Duality of the MAPK Signaling Pathway in the Control of Metabolic Processes and Cellulase Production in Trichoderma reesei. Sci Rep 2018; 8:14931. [PMID: 30297963 PMCID: PMC6175961 DOI: 10.1038/s41598-018-33383-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 09/27/2018] [Indexed: 01/09/2023] Open
Abstract
In this study, through global transcriptional analysis by RNA-Sequencing, we identified the main changes in gene expression that occurred in two functional mutants of the MAPK genes tmk1 and tmk2 in Trichoderma reesei during sugarcane bagasse degradation. We found that the proteins encoded by these genes regulated independent processes, sometimes in a cross-talk manner, to modulate gene expression in T. reesei. In the Δtmk2 strain, growth in sugarcane bagasse modulated the expression of genes involved in carbohydrate metabolism, cell growth and development, and G-protein-coupled receptor-mediated cell signaling. On the other hand, deletion of tmk1 led to decreased expression of the major genes for cellulases and xylanases. Furthermore, TMK1 found to be involved in the regulation of the expression of major facilitator superfamily transporters. Our results revealed that the MAPK signaling pathway in T. reesei regulates many important processes that allow the fungus to recognize, transport, and metabolize different carbon sources during plant cell wall degradation.
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29
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New Genomic Approaches to Enhance Biomass Degradation by the Industrial Fungus Trichoderma reesei. Int J Genomics 2018; 2018:1974151. [PMID: 30345291 PMCID: PMC6174759 DOI: 10.1155/2018/1974151] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/20/2018] [Accepted: 07/29/2018] [Indexed: 11/17/2022] Open
Abstract
The filamentous fungi Trichoderma reesei is one of the most well-studied cellulolytic microorganisms. It is the most important fungus for the industrial production of enzymes to biomass deconstruction being widely used in the biotechnology industry, mainly in the production of biofuels. Here, we performed an analytic review of the holocellulolytic system presented by T. reesei as well as the transcriptional and signaling mechanisms involved with holocellulase expression in this fungus. We also discuss new perspectives about control of secretion and cellulase expression based on RNA-seq and functional characterization data of T. reesei growth in different carbon sources, which comprise glucose, cellulose, sophorose, and sugarcane bagasse.
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30
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Prajapati BP, Kumar Suryawanshi R, Agrawal S, Ghosh M, Kango N. Characterization of cellulase from Aspergillus tubingensis NKBP-55 for generation of fermentable sugars from agricultural residues. BIORESOURCE TECHNOLOGY 2018; 250:733-740. [PMID: 29223094 DOI: 10.1016/j.biortech.2017.11.099] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 06/07/2023]
Abstract
The aim of this work was to characterize cellulase from Aspergillus tubingensis NKBP-55 for generation of fermentable sugars from agricultural residues. The strain produced high titres of cellulase (750 U/gds) on copra meal in solid state fermentation (SSF). The enzyme preparation also showed hemicellulolytic activities (U/gds) viz. endo-mannanase (1023), endo-xylanase (167), β-glucosidase (72) and α-galactosidase (54). Zymography revealed presence of six cellulases, six mannanases and one β-glucosidase. It effectively degraded sugarcane bagasse (SCB) and rice straw (RS) releasing xylose, glucose and cellobiose. One cellulase (Cat 1, Mr ∼65 kDa) was purified and characterized. It retained more than 50% activity at 70 °C after 150 mins and its activity was enhanced in the presence of Mn2+ ions (130%) and β-mercaptoethanol (140%). FTIR and 13C CP/MAS NMR analysis of the enzyme treated SCB and RS revealed degradation of cellulose and hemicellulose, while 1H and 13C liquid state NMR experiments confirmed release of glucose.
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Affiliation(s)
- Bhanu Pratap Prajapati
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Rahul Kumar Suryawanshi
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Sarika Agrawal
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Manasi Ghosh
- Department of Physics, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Naveen Kango
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India.
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