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Jin L, Huang Y, Yang S, Wu D, Li C, Deng W, Zhao K, He Y, Li B, Zhang G, Xiong Y, Wei R, Li G, Wu H, Zhang H, Zou L. Diet, habitat environment and lifestyle conversion affect the gut microbiomes of giant pandas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:145316. [PMID: 33517011 DOI: 10.1016/j.scitotenv.2021.145316] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/02/2021] [Accepted: 01/16/2021] [Indexed: 06/12/2023]
Abstract
Gut microbiota (GM) are important for the health of giant pandas (GPs), in addition to the utilization of bamboo in their diets. However, it is not fully understood how diet, habitat environment and lifestyle contribute to the composition of GM in GP. Consequently, we evaluated how dietary changes, habitat environment conversions and lifestyle shifts influence the GM of GPs using high-throughput sequencing and genome-resolved metagenomics. The GM of GPs were more similar when their hosts exhibited the same diet. High fiber diets significantly increased the diversity and decreased the richness of gut bacterial communities alone or interacted with the age factor (p < 0.05). The abundances of Streptococcus, Pseudomonas, Enterococcus, Lactococcus, Acinetobacter, and Clostridium significantly increased during diet conversion process (Non-parametric factorial Kruskal-Wallis sum-rank test, LDA > 4). Reconstruction of 60 metagenome-assembled-genomes (MAGs) indicated that these bacteria were likely responsible for bamboo digestion via gene complements involved in cellulose, hemicellulose, and lignin degradation. While habitat environment may play a more important role in shaping the GM of GP, lifestyle can also greatly affect bacterial communities. The GM structure in reintroduced GPs notably converged to that of wild pandas. Importantly, the main bacterial genera of wild GPs could aid in lignin degradation, while those of reintroduced GPs were related to cellulose and hemicellulose digestion. Streptococcus, Pseudomonas, Enterococcus, Lactococcus, Acinetobacter, and Clostridium may contribute to lignocellulose digestion in GP. The results revealed that diet conversion, habitat environment and lifestyle could remarkably influence the GM of GP. In addition, results suggested that increasing the ability of lignin degradation with GM may aid to change the GM of reintroduced pandas to resemble those of wild pandas.
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Affiliation(s)
- Lei Jin
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yan Huang
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Shengzhi Yang
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Daifu Wu
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Caiwu Li
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Wenwen Deng
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Ke Zhao
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yongguo He
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Bei Li
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Guiquan Zhang
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Yaowu Xiong
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Rongping Wei
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Guo Li
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Hongning Wu
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Hemin Zhang
- Key Laboratory of State Forestry and Grassland Administration (SFGA) on Conservation Biology of Rare Animals in the Giant Panda National Park, the China Conservation and Research Center for the Giant Panda (CCRCGP), Chengdu, China
| | - Likou Zou
- College of Resources, Sichuan Agricultural University, Chengdu, China.
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Acid soaking followed by steam flash-explosion pretreatment to enhance saccharification of rice husk for poly(3-hydroxybutyrate) production. Int J Biol Macromol 2020; 160:446-455. [DOI: 10.1016/j.ijbiomac.2020.05.218] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 05/15/2020] [Accepted: 05/26/2020] [Indexed: 01/22/2023]
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Deng X, He T, Li J, Duan HL, Zhang ZQ. Enhanced biochemical characteristics of β-glucosidase via adsorption and cross-linked enzyme aggregate for rapid cellobiose hydrolysis. Bioprocess Biosyst Eng 2020; 43:2209-2217. [DOI: 10.1007/s00449-020-02406-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 07/08/2020] [Indexed: 12/20/2022]
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Das A, Basak P, Pramanick A, Majumder R, Pal D, Ghosh A, Guria M, Bhattacharyya M, Banik SP. Trehalose mediated stabilisation of cellobiase aggregates from the filamentous fungus Penicillium chrysogenum. Int J Biol Macromol 2019; 127:365-375. [PMID: 30658143 DOI: 10.1016/j.ijbiomac.2019.01.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 01/12/2019] [Accepted: 01/14/2019] [Indexed: 12/22/2022]
Abstract
Extracellular fungal cellobiases develop large stable aggregates by reversible concentration driven interaction. In-vitro addition of trehalose resulted in bigger cellobiase assemblies with increased stability against heat and dilution induced dissociation. In presence of 0.1 M trehalose, the size of aggregates increased from 344 nm to 494 nm. The increase in size was also observed in zymography of cellobiase. Activation energy of the trehalose stabilised enzyme (Ea = 220.9 kJ/mol) as compared to control (Ea = 257.734 kJ/mol), suggested enhanced thermostability and also showed increased resistance to chaotropes. Purified cellobiase was found to contain 196.27 μg of sugar/μg of protein. It was proposed that presence of glycan on protein's surface impedes and delays trehalose docking. Consequently, self-association of cellobiase preceded coating by trehalose leading to stabilisation of bigger cellobiase aggregates. In unison with the hypothesis, ribosylated BSA failed to get compacted by trehalose and developed into bigger aggregates with average size increasing from 210 nm to 328 nm. Wheat Germ Lectin, in presence of trehalose, showed higher molecular weight assemblies in DLS, native-PAGE and fluorescence anisotropy. This is the first report of cross-linking independent stabilisation of purified fungal glycosidases providing important insights towards understanding the aggregation and stability of glycated proteins.
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Affiliation(s)
- Ahana Das
- Department of Microbiology, Maulana Azad College, 8 Rafi Ahmed Kidwai Road, Kolkata 700013, West Bengal, India
| | - Pijush Basak
- Jagadis Bose National Science Talent Search, 1300, Rajdanga Main Road, Sector C, East Kolkata Township, Kolkata 700107, West Bengal, India
| | - Arnab Pramanick
- Jagadis Bose National Science Talent Search, 1300, Rajdanga Main Road, Sector C, East Kolkata Township, Kolkata 700107, West Bengal, India
| | - Rajib Majumder
- School of Life Science and Biotechnology, Department of Biotechnology, Adamas University, Kolkata 700126, West Bengal, India
| | - Debadrita Pal
- Department of Biology, New Mexico State University, PO Box 30001, MSC 3AF, Las Cruces, NM 88003, United States of America
| | - Avishek Ghosh
- Department of Microbiology, Maulana Azad College, 8 Rafi Ahmed Kidwai Road, Kolkata 700013, West Bengal, India
| | - Manas Guria
- Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019, West Bengal, India
| | - Maitree Bhattacharyya
- Jagadis Bose National Science Talent Search, 1300, Rajdanga Main Road, Sector C, East Kolkata Township, Kolkata 700107, West Bengal, India.
| | - Samudra Prosad Banik
- Department of Microbiology, Maulana Azad College, 8 Rafi Ahmed Kidwai Road, Kolkata 700013, West Bengal, India.
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Aleem B, Rashid MH, Zeb N, Saqib A, Ihsan A, Iqbal M, Ali H. Random mutagenesis of super Koji (Aspergillus oryzae): improvement in production and thermal stability of α-amylases for maltose syrup production. BMC Microbiol 2018; 18:200. [PMID: 30486793 PMCID: PMC6264608 DOI: 10.1186/s12866-018-1345-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/16/2018] [Indexed: 01/26/2023] Open
Abstract
Background Alpha-amylases hydrolyze 1,4 α-glycosidic bonds of starch and produce malto-oligosaccharides. It is an important enzyme generally applied in textile, food and brewing industries. Enhancement in thermal stability and productivity of enzymes are the two most sought after properties for industrial use. The Aspergillus oryzae (Koji) has Generally Recognized as Safe (GRAS) status and safe for use in food industry. Hence, Koji strain’s development for the screening of potent mutants, hyper producer of thermostable α-amylases, with desired attributes is the need of the time. Results A process has been developed to improve super Koji (A. oryzae cmc1) strain through γ-rays treatment. The doses i.e. 0.60, 0.80, 1.00, 1.20 & 1.40 KGy gave more than 3.0 log kill. Initially, 52 Koji mutants resistant to 1% (w/v) Triton X-100 were selected. 2nd screening was based on α-amylases hyper production and 23 mutants were sorted out by measuring clearing zones index (CI). Afterwards nine potent mutants, resistant to 2-deoxy D-glucose, were screened based on CI. These were further analyzed for thermal stability and productivity of α-amylase under submerged conditions. The mutants’ M-80(10), M-100(6) & M-120(5) gave about four fold increases in α-amylases productivity. The half life of M-100(6) α-amylase at 55 °C was 52 min and was highest among the mutants. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis confirmed that mutants did not produce aflatoxins. Field Emission Scanning Electron Microscopy (FESEM) of Koji mycelia depicted that exposure to gamma rays increased rigidity of the mycelium. The potent Koji mutant M-100(6) was grown on soluble starch in 10L fermenter and produced 40.0 IU ml-1 of α-amylases with specific activity of 2461 IU mg-1 protein. Growth kinetic parameters were: μ = Specific growth rate= 0.069 h-1, td = Biomass doubling time= 10.0 h, Yp/x = Product yield coefficient with respect to cell mass = 482 U g-1; qp= Specific rate of product formation= 33.29 U g-1 h-1. Conclusion It was concluded that the developed five step screening process has great potential to generate potent mutants for the hyper production of thermostable enzymes through γ-rays mediated physical mutagenesis. The developed thermostable α-amylases of super Koji mutantM-100(6) has immense potential for application in saccharification process for maltose syrup production. Moreover, the developed five step strain’s development process may be used for the simultaneous improvement in productivity and thermal stability of other microbial enzymes. Electronic supplementary material The online version of this article (10.1186/s12866-018-1345-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bushra Aleem
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan.,Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamaabd, Pakistan
| | - Muhammad Hamid Rashid
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan. .,Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamaabd, Pakistan.
| | - Neelam Zeb
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan
| | - Anam Saqib
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan
| | - Ayesha Ihsan
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan
| | - Mazhar Iqbal
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan
| | - Hazrat Ali
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, P. O. Box 577, Faisalabad, Pakistan
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Partial Purification and Characterization of Cellulolytic Enzymes Extracted from Trichoderma reesei Inoculated Digested Biogas Slurry. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2017. [DOI: 10.22207/jpam.11.4.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Mukherjee S, Khowala S. Unraveling the secretome of Termitomyces clypeatus grown on agroresidues as a potential source for bioethanol production. Process Biochem 2016. [DOI: 10.1016/j.procbio.2015.11.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Tarayre C, Bauwens J, Brasseur C, Mattéotti C, Millet C, Guiot PA, Destain J, Vandenbol M, Portetelle D, De Pauw E, Haubruge E, Francis F, Thonart P. Isolation and cultivation of xylanolytic and cellulolytic Sarocladium kiliense and Trichoderma virens from the gut of the termite Reticulitermes santonensis. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:4369-4382. [PMID: 25300185 DOI: 10.1007/s11356-014-3681-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 10/01/2014] [Indexed: 06/04/2023]
Abstract
The purpose of this work was the isolation and cultivation of cellulolytic and xylanolytic microorganisms extracted from the gut of the lower termite Reticulitermes santonensis. Microcrystalline cellulose (with and without lignin) and beech wood xylan were used as diets instead of poplar wood in order to select cellulose and hemicellulose-degrading fungi. The strain Sarocladium kiliense (Acremonium kiliense) CTGxxyl was isolated from the termites fed on xylan, while the strain Trichoderma virens CTGxAviL was isolated from the termites fed on cellulose (with and without lignin). Both molds were cultivated in liquid media containing different substrates: agro-residues or purified polymers. S. kiliense produced maximal β-glucosidase, endo-1,4-β-D-glucanase, exo-1,4-β-D-glucanase and endo-1,4-β-D-xylanase activities of 0.103, 3.99, 0.53, and 40.8 IU/ml, respectively. T. virens produced maximal β-xylosidase, endo-1,4-β-D-glucanase, exo-1,4-β-D-glucanase, and endo-1,4-β-D-xylanase activities of 0.38, 1.48, 0.69, and 426 IU/ml. The cellulase and the xylanase of S. kiliense, less common than T. virens, were further investigated. The optimal activity of the xylanase was observed at pH 9-10 at 60 °C. The cellulase showed its maximal activity at pH 10, 70 °C. Zymography identified different xylanases produced by both molds, and some fragment sizes were highlighted: 35, 100, and 170 kDa for S. kiliense and 20, 40, 80, and 170 kDa for T. virens. In both cases, endo-1,4-β-D-xylanase activities were confirmed through mass spectrometry.
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Affiliation(s)
- Cédric Tarayre
- Unit of Bio-Industries, Gembloux Agro-Bio Tech, University of Liège, 5030, Gembloux, Belgium,
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Lai C, Zeng GM, Huang DL, Zhao MH, Wei Z, Huang C, Xu P, Li NJ, Zhang C, Chen M, Li X, Lai M, He Y. Synthesis of gold-cellobiose nanocomposites for colorimetric measurement of cellobiase activity. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 132:369-374. [PMID: 24887498 DOI: 10.1016/j.saa.2014.04.091] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 03/28/2014] [Accepted: 04/13/2014] [Indexed: 06/03/2023]
Abstract
Gold-cellobiose nanocomposites (GCNCs) were synthesized by reducing gold salt with a polysaccharide, cellobiose. Here, cellobiose acted as a controller of nucleation or stabilizer in the formation of gold nanoparticles. The obtained GCNCs were characterized with UV-visible spectroscopy; Zetasizer and Fourier transform infrared (FT-IR) spectrophotometer. Moreover, 6-Mercapto-1-hexanol (MCH) was modified on GCNCs, and the MCH-GCNCs were used to determine the cellobiase activity in compost extracts based on the surface plasmon resonance (SPR) property of MCH-GCNCs. The degradation of cellobiose on MCH-GCNCs by cellobiase could induce the aggregation, and the SPR absorption wavelength of MCH-GCNCs correspondingly red shifted. Thus, the absorbance ratio of treated MCH-GCNCs (A650/A520) could be used to estimate the cellobiase activity, and the probe exhibited highly sensitive and selective detection of the cellobiase activity with a wide linear from 3.0 to 100.0U L(-1) within 20 min. Meanwhile, a good linear relationship with correlation coefficient of R2=0.9976 was obtained. This approach successfully showed the suitability of gold nanocomposites as a colorimetric sensor for the sensitive and specific enzyme activity detection.
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Affiliation(s)
- Cui Lai
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Guang-Ming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China.
| | - Dan-Lian Huang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China.
| | - Mei-Hua Zhao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Zhen Wei
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Chao Huang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Piao Xu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Ning-Jie Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Chen Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Ming Chen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Xue Li
- Department of Bioengineering and Environmental Science, Changsha University, Changsha 410003, Hunan, PR China
| | - Mingyong Lai
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
| | - Yibin He
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, Hunan, PR China
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Banik SP, Mukherjee S, Pal S, Ghorai S, Majumder R, Khowala S. Enhancement of extracellular cellobiase activity by reducing agents in the filamentous fungus Termitomyces clypeatus. Biotechnol Lett 2014; 37:175-81. [PMID: 25257587 DOI: 10.1007/s10529-014-1669-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Extracellular cellobiase activity of Termitomyces clypeatus increased from 2.9 U ml(-1) to 4.4 and 4.1 in presence of dithiothreitol (DTT) and β-mercaptoethanol (ME), respectively, with a decrease in Km from 0.4 to 0.3 mM (DTT) and 0.35 mM (ME). Catalysis was further enhanced if the reduced enzyme was alkylated and activity increased from 11.4 U ml(-1) (control) to 15.2 (DTT+N-ethylmaleimide) and 15.3 (DTT+iodoacetamide) using p-nitrophenyl-β-D-glucopyranoside and from 14.6 U ml(-1)(control) to 21.9 (DTT+N-ethylmaleimide) and 18.7 (DTT+iodoacetamide) using cellobiose. The reduced enzyme showed 17 % lesser glucose inhibition. CD and tryptophan fluorescence showed no change in secondary structure was caused by DTT up to 50 mM. Cysteine content of the enzyme was 24 %. It is postulated that reduction of disulphide bonds allows better substrate affinity for cellobiase. The studies describe a novel and simple method to increase cellobiase activity for industrial applications.
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Affiliation(s)
- Samudra Prosad Banik
- Department of Microbiology, Maulana Azad College, 8 Rafi Ahmed Kidwai Road, Kolkata, 700013, India
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In situ reversible aggregation of extracellular cellobiase in the filamentous fungus Termitomyces clypeatus. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-012-0002-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Pal S, Banik SP, Ghorai S, Chowdhury S, Khowala S. Increased enzyme secretion by 2-deoxy-D-glucose in presence of succinate by suppression of metabolic enzymes in Termitomyces clypeatus. Carbohydr Res 2011; 346:2426-31. [PMID: 21920514 DOI: 10.1016/j.carres.2011.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 07/27/2011] [Accepted: 08/12/2011] [Indexed: 11/15/2022]
Abstract
Regulatory mode of secretion of proteins was detected for the industrial glycosidase, cellobiase, under secreting conditions (in presence of TCA cycle intermediates like succinate etc.) in the filamentous fungus Termitomyces clypeatus. The titers of key metabolic enzymes were investigated under secreting and non-secreting conditions of growth and compared to the corresponding production of intra and extracellular levels of cellobiase. Results were compared in presence of 2-deoxy-D-glucose, a potent glycosylation inhibitor in the secreting media. Inclusion of 2-deoxy-D-glucose in presence of succinate caused about 10 to 100 times decrease in titers of the metabolic enzymes hexokinase, fructose-1,6-bisphosphatase, isocitrate lyase and malate dehydrogenase leading to increased secretion of cellobiase by more than 100 times. The intracellular concentration of cAMP (86-fold decrease in presence of 2-deoxy-D-glucose under secreting conditions) and turnover rate of proteins also dropped significantly. In this suppressed metabolic state, a 10-fold increase in the titer of the secreted cellobiase was noticed. The results indicated elucidation of carbon catabolite repression like phenomenon in the fungus under secreting conditions which was more pronounced by 2-deoxy-D-glucose. The interdependence between secretion and regulation of metabolic enzymes will help in better understanding of the physiology of these highly adapted organisms for increasing their secretion potential of glycosidases like cellobiase with high industrial value.
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Affiliation(s)
- Swagata Pal
- Indian Institute of Chemical Biology (Unit of CSIR, Govt. of India), Drug Development and Biotechnology Division, 4, Raja S.C. Mullick Road, Kolkata 700 032, India
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Improved production and properties of β-glucosidase influenced by 2-deoxy-d-glucose in the culture medium of Termitomyces clypeatus. BIOTECHNOL BIOPROC E 2011. [DOI: 10.1007/s12257-010-0236-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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