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Han H, Ling Z, Khan A, Virk AK, Kulshrestha S, Li X. Improvements of thermophilic enzymes: From genetic modifications to applications. BIORESOURCE TECHNOLOGY 2019; 279:350-361. [PMID: 30755321 DOI: 10.1016/j.biortech.2019.01.087] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 06/09/2023]
Abstract
Thermozymes (from thermophiles or hyperthermophiles) offer obvious advantages due to their excellent thermostability, broad pH adaptation, and hydrolysis ability, resulting in diverse industrial applications including food, paper, and textile processing, biofuel production. However, natural thermozymes with low yield and poor adaptability severely hinder their large-scale applications. Extensive studies demonstrated that using genetic modifications such as directed evolution, semi-rational design, and rational design, expression regulations and chemical modifications effectively improved enzyme's yield, thermostability and catalytic efficiency. However, mechanism-based techniques for thermozymes improvements and applications need more attention. In this review, stabilizing mechanisms of thermozymes are summarized for thermozymes improvements, and these improved thermozymes eventually have large-scale industrial applications.
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Affiliation(s)
- Huawen Han
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Zhenmin Ling
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Aman Khan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Amanpreet Kaur Virk
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229, India
| | - Saurabh Kulshrestha
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229, India
| | - Xiangkai Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China.
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Hyper production of cellulose degrading endo (1,4) β-d-glucanase fromBacillus licheniformisKIBGE-IB2. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2019. [DOI: 10.1016/j.jrras.2014.06.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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53
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Patel AK, Singhania RR, Sim SJ, Pandey A. Thermostable cellulases: Current status and perspectives. BIORESOURCE TECHNOLOGY 2019; 279:385-392. [PMID: 30685132 DOI: 10.1016/j.biortech.2019.01.049] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/09/2019] [Accepted: 01/11/2019] [Indexed: 05/18/2023]
Abstract
It is envisaged that the utilization of lignocellulosic biomass for ethanol production for transport sector, would make cellulases the most demanded industrial enzyme. The greatest potential of cellulolytic enzymes lies in ethanol production from biomass by enzymatic hydrolysis of cellulose but low thermostability and low titer of cellulase production resulting into high cost of the enzyme which is the major set-back. A number of research groups are working on cellulase to improve its thermostability so as to be able to perform hydrolysis at elevated temperatures which would eventually increase the efficiency of cellulose hydrolysis. The technologies developed from lignocellulosic biomass via cellulose hydrolysis promise environmental and economical sustainability in the long run along with non-dependence on nonrenewable energy source. This review deals with the important sources of thermostable cellulases, mechanism, its regulation, strategies to enhance the thermostability further with respect to its importance for biofuel applications.
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Affiliation(s)
- Anil K Patel
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | | | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Ashok Pandey
- Centre for Innovation and Translational Research, Indian Institute of Toxicological Research, Lucknow 226 001, India
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Rathinam NK, Bibra M, Rajan M, Salem D, Sani RK. Short term atmospheric pressure cold plasma treatment: A novel strategy for enhancing the substrate utilization in a thermophile, Geobacillus sp. strain WSUCF1. BIORESOURCE TECHNOLOGY 2019; 278:477-480. [PMID: 30679060 DOI: 10.1016/j.biortech.2019.01.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/07/2019] [Accepted: 01/08/2019] [Indexed: 06/09/2023]
Abstract
The aim of this study was to investigate the effect of atmospheric pressure cold plasma on the microbial substrate utilization and biomass yield in a thermophilic strain. Geobacillus sp. strain WSUCF1, a thermophile capable of producing cellulolytic enzymes with higher activity was used for this investigation. Treatment with cold plasma for 4 min increased the rates of glucose utilization by 74% and biomass yield by 60% when compared with the control. WSUCF1 treated with plasma also displayed enhanced biofilm formation. This study for the first time, reports the use of cold plasma for enhancing the substrate utilization and biofilm formation in a thermophile.
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Affiliation(s)
- Navanietha K Rathinam
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA; BuG ReMeDEE Consortia, South Dakota School of Mines and Technology, Rapid City, SD, USA.
| | - Mohit Bibra
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA
| | - Magesh Rajan
- Department of Electrical Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA
| | - David Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA; Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD 57701, USA
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA; BuG ReMeDEE Consortia, South Dakota School of Mines and Technology, Rapid City, SD, USA; Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD 57701, USA; Department of Chemistry and Applied Biological Sciences, South Dakota School of Mines and Technology, Rapid City, SD, USA
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Wang J, Goh KM, Salem DR, Sani RK. Genome analysis of a thermophilic exopolysaccharide-producing bacterium - Geobacillus sp. WSUCF1. Sci Rep 2019; 9:1608. [PMID: 30733471 PMCID: PMC6367360 DOI: 10.1038/s41598-018-36983-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/16/2018] [Indexed: 11/23/2022] Open
Abstract
Geobacillus sp. WSUCF1 is a Gram-positive, spore-forming, aerobic and thermophilic bacterium, isolated from a soil sample obtained from a compost facility. Strain WSUCF1 demonstrated EPS producing capability using different sugars as the carbon source. The whole-genome analysis of WSUCF1 was performed to disclose the essential genes correlated with nucleotide sugar precursor biosynthesis, assembly of monosaccharide units, export of the polysaccharide chain, and regulation of EPS production. Both the biosynthesis pathway and export mechanism of EPS were proposed based on functional annotation. Additionally, the genome description of strain WSUCF1 suggests sophisticated systems for its adaptation under thermophilic conditions. The presence of genes associated with CRISPR-Cas system, quorum quenching lactonase, polyketide synthesis and arsenic resistance makes this strain a potential candidate for various applications in biotechnology and biomedicine. The present study indicates that strain WSUCF1 has promise as a thermophilic EPS producer for a broad range of industrial applications. To the best of our knowledge, this is the first report on genome analysis of a thermophilic Geobacillus species focusing on its EPS biosynthesis and transportation, which will likely pave the way for both enhanced yield and tailor-made EPS production by thermophilic bacteria.
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Affiliation(s)
- Jia Wang
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
| | - Kian Mau Goh
- Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, 81300, Malaysia
| | - David R Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Department of Materials and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
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Naresh S, Kunasundari B, Gunny AAN, Teoh YP, Shuit SH, Ng QH, Hoo PY. Isolation and Partial Characterisation of Thermophilic Cellulolytic Bacteria from North Malaysian Tropical Mangrove Soil. Trop Life Sci Res 2019; 30:123-147. [PMID: 30847037 PMCID: PMC6396887 DOI: 10.21315/tlsr2019.30.1.8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
This study reports the biodiversity of thermophilic cellulolytic bacterial strains that present in the north Malaysian mangrove ecosystem. Soil samples were collected at the four most northern state of Malaysia (Perak, Pulau Pinang, Kedah and Perlis). The samples obtained were first enriched in nutrient broth at 45°C and 55°C prior culturing in the carboxymethylcellulose (CMC) agar medium. Repeated streaking was performed on the CMC agar to obtain a pure culture of each isolate prior subjecting it to hydrolysis capacity testing. The isolates that showing the cellulolytic zone (halozone) were sent for 16S rRNA sequencing. Total seven isolates (two from Perak, three from Kedah, another two were from Perlis and Penang each) showed halozone. The isolate (KFX-40) from Kedah exhibited highest halozone of 3.42 ± 0.58, meanwhile, the one obtained from Perak (AFZ-0) showed the lowest hydrolysis capacity (2.61 ± 0.10). Based on 16S rRNA sequencing results, 5 isolates (AFY-40, AFZ-0, KFX-40, RFY-20, and PFX-40) were determined to be Anoxybacillus sp. The other two isolates were identified as Bacillus subtilis (KFY-40) and Paenibacillus dendritiformis (KFX-0). Based on growth curve, doubling time of Anoxybacillus sp. UniMAP-KB06 was calculated to be 32.3 min. Optimal cellulose hydrolysis temperature and pH of this strain were determined to be 55°C and 6.0 respectively. Addition of Mg2+ and Ca2+ were found to enhance the cellulase activity while Fe3+ acted as an enzyme inhibitor.
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Affiliation(s)
- Sandrasekaran Naresh
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Balakrishnan Kunasundari
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Ahmad Anas Nagoor Gunny
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Yi Peng Teoh
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Siew Hoong Shuit
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Qi Hwa Ng
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
| | - Peng Yong Hoo
- Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O Box 77, D/A Pejabat Pos Besar Kangar, 01000, Perlis, Malaysia
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Singh G, Patel AK, Gupta A, Gupta D, Mishra VK. Current Advancements in Recombinant Technology for Industrial Production of Cellulases: Part-II. Fungal Biol 2019. [DOI: 10.1007/978-3-030-14726-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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58
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Song C, Zhang Y, Xia X, Qi H, Li M, Pan H, Xi B. Effect of inoculation with a microbial consortium that degrades organic acids on the composting efficiency of food waste. Microb Biotechnol 2018; 11:1124-1136. [PMID: 29968359 PMCID: PMC6196389 DOI: 10.1111/1751-7915.13294] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 05/25/2018] [Accepted: 06/04/2018] [Indexed: 12/04/2022] Open
Abstract
In order to overcome the excessive acidification problem, a microbial consortium for the degradation of organic acids (MCDOA), which acts synergistically in degrading organic acids, was developed and used as an inoculum to improve the efficiency of food waste composting. MCDOA could eliminate the initial lag phase of the pile temperature rise because of excessive acidification and effectively shorten the composting period. Fluorescence regional integration analysis of the excitation-emission matrix spectra of dissolved organic matter showed that compared with raw material, in compost with MCDOA inoculation, the percent fluorescence response (Pi,n ) values of Regions I, II and IV decreased by 95.11%, 94.19% and 87.41%, respectively, and Pi,n of Region V increased by 172.57%. The decreased and increased levels were markedly higher than in the two control groups (MgO and K2 HPO4 treatment, and uninoculated compost). These findings revealed that MCDOA accelerated the degradation of proteinaceous compounds and the formation of complicated humic-like materials. Bacterial profiles implied that MCDOA could improve the indigenous bacterial community structure and diversities of acetic and propionic acid-degrading and lignin-degrading bacteria, which might account for the high composting efficiency and degree of humification of the inoculated compost.
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Affiliation(s)
- Caihong Song
- Life Science CollegeLiaocheng UniversityNo. 1, Hunan Road, Dongchangfu DistrictLiaochengChina
| | - Yali Zhang
- Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China
- Center for Chinese Agricultural PolicyChinese Academy of SciencesBeijing100101China
| | - Xunfeng Xia
- Innovation Base of Groundwater and Environmental Systems EngineeringChinese Research Academy of Environmental SciencesNo. 8, Dayangfang, Beiyuan Road, Chaoyang DistrictBeijing100012China
| | - Hui Qi
- Life Science CollegeLiaocheng UniversityNo. 1, Hunan Road, Dongchangfu DistrictLiaochengChina
| | - Mingxiao Li
- Innovation Base of Groundwater and Environmental Systems EngineeringChinese Research Academy of Environmental SciencesNo. 8, Dayangfang, Beiyuan Road, Chaoyang DistrictBeijing100012China
| | - Hongwei Pan
- North China University of Water Resources and Electric PowerZhengzhou450011China
| | - Beidou Xi
- Innovation Base of Groundwater and Environmental Systems EngineeringChinese Research Academy of Environmental SciencesNo. 8, Dayangfang, Beiyuan Road, Chaoyang DistrictBeijing100012China
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Orellana R, Macaya C, Bravo G, Dorochesi F, Cumsille A, Valencia R, Rojas C, Seeger M. Living at the Frontiers of Life: Extremophiles in Chile and Their Potential for Bioremediation. Front Microbiol 2018; 9:2309. [PMID: 30425685 PMCID: PMC6218600 DOI: 10.3389/fmicb.2018.02309] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/10/2018] [Indexed: 11/19/2022] Open
Abstract
Extremophiles are organisms capable of adjust, survive or thrive in hostile habitats that were previously thought to be adverse or lethal for life. Chile gathers a wide range of extreme environments: salars, geothermal springs, and geysers located at Altiplano and Atacama Desert, salars and cold mountains in Central Chile, and ice fields, cold lakes and fjords, and geothermal sites in Patagonia and Antarctica. The aims of this review are to describe extremophiles that inhabit main extreme biotopes in Chile, and their molecular and physiological capabilities that may be advantageous for bioremediation processes. After briefly describing the main ecological niches of extremophiles along Chilean territory, this review is focused on the microbial diversity and composition of these biotopes microbiomes. Extremophiles have been isolated in diverse zones in Chile that possess extreme conditions such as Altiplano, Atacama Desert, Central Chile, Patagonia, and Antarctica. Interesting extremophiles from Chile with potential biotechnological applications include thermophiles (e.g., Methanofollis tationis from Tatio Geyser), acidophiles (e.g., Acidithiobacillus ferrooxidans, Leptospirillum ferriphilum from Atacama Desert and Central Chile copper ores), halophiles (e.g., Shewanella sp. Asc-3 from Altiplano, Streptomyces sp. HKF-8 from Patagonia), alkaliphiles (Exiguobacterium sp. SH31 from Altiplano), xerotolerant bacteria (S. atacamensis from Atacama Desert), UV- and Gamma-resistant bacteria (Deinococcus peraridilitoris from Atacama Desert) and psychrophiles (e.g., Pseudomonas putida ATH-43 from Antarctica). The molecular and physiological properties of diverse extremophiles from Chile and their application in bioremediation or waste treatments are further discussed. Interestingly, the remarkable adaptative capabilities of extremophiles convert them into an attractive source of catalysts for bioremediation and industrial processes.
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Affiliation(s)
- Roberto Orellana
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
- Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile
| | - Constanza Macaya
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Guillermo Bravo
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Flavia Dorochesi
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Andrés Cumsille
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Ricardo Valencia
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Claudia Rojas
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Michael Seeger
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
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Thankappan S, Kandasamy S, Joshi B, Sorokina KN, Taran OP, Uthandi S. Bioprospecting thermophilic glycosyl hydrolases, from hot springs of Himachal Pradesh, for biomass valorization. AMB Express 2018; 8:168. [PMID: 30324223 PMCID: PMC6188974 DOI: 10.1186/s13568-018-0690-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 09/26/2018] [Indexed: 01/17/2023] Open
Abstract
The harnessing of biocatalysts from extreme environment hot spring niche for biomass conversion is significant and promising owing to the special characteristics of extremozymes attributed by intriguing biogeochemistry and extreme conditions of these environments. Hence, in the present study 38 bacterial isolates obtained from hot springs of Manikaran (~ 95 °C), Kalath (~ 50 °C) and Vasist (~ 65 °C) of Himachal Pradesh were screened for glycosyl hydrolases by in situ enrichment technique using lignocellulosic biomass (LCB). Based on their hydrolytic potential 5 isolates were selected and they were Bacillus tequilensis (VCB1, VCB2 and VSDB4), and B. licheniformis (KBFB2 and KBFB3). Cellulolytic activity assayed by growth under submerged fermentation showed that B. tequilensis VCB1 had maximum FPA activity (3.38 IU ml−1) in 48 h, while B. licheniformis KBFB3 excelled for endoglucanase (EGA of 4.81 IU ml−1 in 24 h) and cellobiase (0.71 IU ml−1 in 48 h) activities. Among all the thermophilic biocatalysts evaluated, highest exoglucanase (0.06 IU ml−1) activity was observed in B. tequilensis VSDB4 while endoglucanase of B. licheniformis KBFB3 showed optimum specific activity at pH 7 and 70 °C. Further, the presence of celS, celB and xlnB genes in the isolates suggest their possible role in biomass conversion. Protein profiling by SDS-PAGE analysis revealed that cellulase isoforms migrated with molecular masses of 75 kDa. The endoglucanase activity of promising strain B. licheniformis KBFB3 was enhanced in the presence of Ca2+, mercaptoethanol and sodium hypochlorite whereas moderately inhibited by Cu2+, Zn2+, urea, SDS and H2O2. The results of this study indicate scope for the possible development of novel biocatalysts with multifunctional thermostable glycosyl hydrolases from hot springs for efficient hydrolysis of the complex lignocellulosic biomass into simple sugars and other derived bioproducts leading to biomass valorization.
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Exploring the gut of Helicoverpa armigera for cellulose degrading bacteria and evaluation of a potential strain for lignocellulosic biomass deconstruction. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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62
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Thermostable Xylanase Production by Geobacillus sp. Strain DUSELR13, and Its Application in Ethanol Production with Lignocellulosic Biomass. Microorganisms 2018; 6:microorganisms6030093. [PMID: 30189618 PMCID: PMC6164562 DOI: 10.3390/microorganisms6030093] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/29/2018] [Accepted: 08/31/2018] [Indexed: 01/11/2023] Open
Abstract
The aim of the current study was to optimize the production of xylanase, and its application for ethanol production using the lignocellulosic biomass. A highly thermostable crude xylanase was obtained from the Geobacillus sp. strain DUSELR13 isolated from the deep biosphere of Homestake gold mine, Lead, SD. Geobacillus sp. strain DUSELR13 produced 6 U/mL of the xylanase with the beechwood xylan. The xylanase production was improved following the optimization studies, with one factor at a time approach, from 6 U/mL to 19.8 U/mL with xylan. The statistical optimization with response surface methodology further increased the production to 31 U/mL. The characterization studies revealed that the crude xylanase complex had an optimum pH of 7.0, with a broad pH range of 5.0⁻9.0, and an optimum temperature of 75 °C. The ~45 kDa xylanase protein was highly thermostable with t1/2 of 48, 38, and 13 days at 50, 60, and 70 °C, respectively. The xylanase activity increased with the addition of Cu+2, Zn+2, K+, and Fe+2 at 1 mM concentration, and Ca+2, Zn+2, Mg+2, and Na⁺ at 10 mM concentration. The comparative analysis of the crude xylanase against its commercial counterpart Novozymes Cellic HTec and Dupont, Accellerase XY, showed that it performed better at higher temperature, hydrolyzing 65.4% of the beechwood at 75 °C. The DUSEL R13 showed the mettle to hydrolyze, and utilize the pretreated, and untreated lignocellulosic biomass: prairie cord grass (PCG), and corn stover (CS) as the substrate, and gave a maximum yield of 20.5 U/mL with the untreated PCG. When grown in co-culture with Geobacillus thermoglucosidasius, it produced 3.53 and 3.72 g/L ethanol, respectively with PCG, and CS. With these characteristics the xylanase under study could be an industrial success for the high temperature bioprocesses.
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Isolation and Characterization of Novel Lignolytic, Cellulolytic, and Hemicellulolytic Bacteria from Wood-Feeding Termite Cryptotermes brevis. Int Microbiol 2018; 22:29-39. [DOI: 10.1007/s10123-018-0024-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/10/2018] [Accepted: 07/11/2018] [Indexed: 10/28/2022]
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64
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Hao Z, Yang B, Jahng D. Spent coffee ground as a new bulking agent for accelerated biodrying of dewatered sludge. WATER RESEARCH 2018; 138:250-263. [PMID: 29605704 DOI: 10.1016/j.watres.2018.03.049] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/01/2018] [Accepted: 03/20/2018] [Indexed: 06/08/2023]
Abstract
The feasibility of using spent coffee ground (SCG) as a new bulking agent for biodrying of dewatered sludge (DS) was investigated in comparison with two other frequently-used bulking agents, air-dried sludge (AS) and sawdust (SD). Results showed that the moisture contents (MC) of 16-day DS biodrying with AS (Trial A), SCG (Trial B) and SD (Trial C) decreased from 70.14 wt%, 68.25 wt% and 71.63 wt% to 59.12 wt%, 41.35 wt% and 57.69 wt%, respectively. In case of Trial B, the MC rapidly decreased to 46.16 wt% with the highest water removal (70.87%) within 8 days because of the longest high-temperature period (5.8 days). Further studies indicated that the abundant biodegradable volatile solids (BVS) and high dissolved organic matter (DOM) contents in SCG were the main driving forces for water removal. According to pyrosequencing data, Firmicutes, most of which were recognized as thermophiles, was rapidly enriched on Day 8 and became the dominant phylum in Trial B. Four thermophilic genera, Bacillus, Ureibacillus, Geobacillus and Thermobifida, which can produce thermostable hydrolytic extracellular enzymes, were the most abundant in Trial B, indicating that these thermophilic bacteria evolved during the long high-temperature period enhanced the biodegradation of BVS in SCG. The 8-day biodried product of Trial B was demonstrated to be an excellent solid fuel with low heating value (LHV) of 9284 kJ kg-1, which was 2.1 and 1.8 times those of biodried products with AS and SD, respectively. Thus SCG was found to be an excellent bulking agent accelerating DS biodrying and producing a solid fuel with a high calorific value.
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Affiliation(s)
- Zongdi Hao
- Department of Environmental Engineering & Energy, Myongji University, 116 Myongjiro, Cheoingu, Yonginshi, Gyeonggido, 17058, Republic of Korea
| | - Benqin Yang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, People's Republic of China
| | - Deokjin Jahng
- Department of Environmental Engineering & Energy, Myongji University, 116 Myongjiro, Cheoingu, Yonginshi, Gyeonggido, 17058, Republic of Korea.
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Lepcha K, Ghosh S. Glycoside hydrolases from a thermophilic microbial consortium and their implication in the saccharification of agroresidues. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2018. [DOI: 10.1016/j.bcab.2018.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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66
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Daas MJA, Nijsse B, van de Weijer AHP, Groenendaal BWAJ, Janssen F, van der Oost J, van Kranenburg R. Engineering Geobacillus thermodenitrificans to introduce cellulolytic activity; expression of native and heterologous cellulase genes. BMC Biotechnol 2018; 18:42. [PMID: 29945583 PMCID: PMC6020330 DOI: 10.1186/s12896-018-0453-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 06/14/2018] [Indexed: 11/28/2022] Open
Abstract
Background Consolidated bioprocessing (CBP) is a cost-effective approach for the conversion of lignocellulosic biomass to biofuels and biochemicals. The enzymatic conversion of cellulose to glucose requires the synergistic action of three types of enzymes: exoglucanases, endoglucanases and β-glucosidases. The thermophilic, hemicellulolytic Geobacillus thermodenitrificans T12 was shown to harbor desired features for CBP, although it lacks the desired endo and exoglucanases required for the conversion of cellulose. Here, we report the expression of both endoglucanase and exoglucanase encoding genes by G. thermodenitrificans T12, in an initial attempt to express cellulolytic enzymes that complement the enzymatic machinery of this strain. Results A metagenome screen was performed on 73 G. thermodenitrificans strains using HMM profiles of all known CAZy families that contain endo and/or exoglucanases. Two putative endoglucanases, GE39 and GE40, belonging to glucoside hydrolase family 5 (GH5) were isolated and expressed in both E. coli and G. thermodenitrificans T12. Structure modeling of GE39 revealed a folding similar to a GH5 exo-1,3-β-glucanase from S. cerevisiae. However, we determined GE39 to be a β-xylosidase having pronounced activity towards p-nitrophenyl-β-d-xylopyranoside. Structure modelling of GE40 revealed its protein architecture to be similar to a GH5 endoglucanase from B. halodurans, and its endoglucanase activity was confirmed by enzymatic activity against 2-hydroxyethylcellulose, carboxymethylcellulose and barley β-glucan. Additionally, we introduced expression constructs into T12 containing Geobacillus sp. 70PC53 endoglucanase gene celA and both endoglucanase genes (M1 and M2) from Geobacillus sp. WSUCF1. Finally, we introduced expression constructs into T12 containing the C. thermocellum exoglucanases celK and celS genes and the endoglucanase celC gene. Conclusions We identified a novel G. thermodenitrificans β-xylosidase (GE39) and a novel endoglucanase (GE40) using a metagenome screen based on multiple HMM profiles. We successfully expressed both genes in E. coli and functionally expressed the GE40 endoglucanase in G. thermodenitrificans T12. Additionally, the heterologous production of active CelK, a C. thermocellum derived exoglucanase, and CelA, a Geobacillus derived endoglucanase, was demonstrated with strain T12. The native hemicellulolytic activity and the heterologous cellulolytic activity described in this research provide a good basis for the further development of G. thermodenitrificans T12 as a host for consolidated bioprocessing. Electronic supplementary material The online version of this article (10.1186/s12896-018-0453-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martinus J A Daas
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Bart Nijsse
- Laboratory of Systems and Synthetic Biology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | | | - Bart W A J Groenendaal
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Fons Janssen
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands. .,Corbion, Arkelsedijk 46, 4206, AC, Gorinchem, The Netherlands.
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Liang J, Fang X, Lin Y, Wang D. A new screened microbial consortium OEM2 for lignocellulosic biomass deconstruction and chlorophenols detoxification. JOURNAL OF HAZARDOUS MATERIALS 2018; 347:341-348. [PMID: 29335216 DOI: 10.1016/j.jhazmat.2018.01.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 12/13/2017] [Accepted: 01/10/2018] [Indexed: 06/07/2023]
Abstract
Recalcitrance limits biomass application in biorefinery. It is even more so when toxic chlorophenols are present. In this study, we screened a microbial consortium, OEM2, for lignocellulose deconstruction and chlorophenols detoxification through a short-term and efficient screening process. Microbial consortium OEM2 had a good buffer capability in the cultivation process and exhibited a high xylanase activity, with over 85% hemicellulose degradation within 12 days. Throughout the treatment process, 41.5% rice straw decomposition on day 12 and around 75% chlorophenols (MCP, 2,4-DCP, 2,4,6-TCP) removal on day 9, were recorded. Moreover, Fourier translation infrared spectroscopy (FTIR) analysis indicated that chemical bonds and groups (eg. hydrogen-bond, β-1,4 glycosidic bond, lignin-carbohydrate cross-linking) in the rice straw were broken. Cuticle and silica layer destruction and subsequent exposed cellulose fibers were observed by scanning electron microscopy (SEM). Microbial consortium OEM2 diversity analysis by 16S rRNA gene sequencing indicated that Proteobacteria (41.3%) was the most abundant phylum and the genera Paenibacillus and Pseudomonas played an important role in the lignocellulose decomposition and chlorophenols detoxification. This study developed a faster and more efficient strategy to screen a specific microbial consortium. And the new microbial consortium, OEM2, makes lignocellulose more accessible and complex pollutants unproblematic in the further biorefinery process.
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Affiliation(s)
- Jiajin Liang
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Xiuxiu Fang
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China; Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Yunqin Lin
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China; Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, Guangdong 510642, PR China.
| | - Dehan Wang
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China; Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
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Su X, Zhang S, Mei R, Zhang Y, Hashmi MZ, Liu J, Lin H, Ding L, Sun F. Resuscitation of viable but non-culturable bacteria to enhance the cellulose-degrading capability of bacterial community in composting. Microb Biotechnol 2018. [PMID: 29536669 PMCID: PMC5902322 DOI: 10.1111/1751-7915.13256] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Nowadays, much of what we know regarding the isolated cellulolytic bacteria comes from the conventional plate separation techniques. However, the culturability of many bacterial species is controlled by resuscitation‐promoting factors (Rpfs) due to entering a viable but non‐culturable (VBNC) state. Therefore, in this study, Rpf from Micrococcus luteus was added in the culture medium to evaluate its role in bacterial isolation and enhanced effects on cellulose‐degrading capability of bacterial community in the compost. It was found that Proteobacteria and Actinobacteria were two main phyla in the compost sample. The introduction of Rpf could isolate some unique bacterial species. The cellulase activity of enrichment cultures with and without Rpf treatment revealed that Rpf treatment significantly enhanced cellulase activity. Ten isolates unique in Rpf addition displayed carboxymethyl‐cellulase (CMCase) activity, while six isolates possessed filter paper cellulase (FPCase) activity. This study provides new insights into broader cellulose degraders, which could be utilized for enhancing cellulosic waste treatment.
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Affiliation(s)
- Xiaomei Su
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Shuo Zhang
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Rongwu Mei
- Environmental Science Research and Design Institute of Zhejiang Province, Hangzhou, 310007, China
| | - Yu Zhang
- Environmental Science Research and Design Institute of Zhejiang Province, Hangzhou, 310007, China
| | - Muhammad Zaffar Hashmi
- Department of Meteorology, COMSATS Institute of Information Technology, Islamabad, 44000, Pakistan
| | - Jingjing Liu
- Department of Architecture and Resources Engineering, Jiangxi University of Science and Technology, Nanchang, 310013, China
| | - Hongjun Lin
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Linxian Ding
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Faqian Sun
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
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Jiang Y, Xin F, Lu J, Dong W, Zhang W, Zhang M, Wu H, Ma J, Jiang M. State of the art review of biofuels production from lignocellulose by thermophilic bacteria. BIORESOURCE TECHNOLOGY 2017. [PMID: 28634129 DOI: 10.1016/j.biortech.2017.05.142] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Biofuels, including ethanol and butanol, are mainly produced by mesophilic solventogenic yeasts and Clostridium species. However, these microorganisms cannot directly utilize lignocellulosic materials, which are abundant, renewable and non-compete with human demand. More recently, thermophilic bacteria show great potential for biofuels production, which could efficiently degrade lignocellulose through the cost effective consolidated bioprocessing. Especially, it could avoid contamination in the whole process owing to its relatively high fermentation temperature. However, wild types thermophiles generally produce low levels of biofuels, hindering their large scale production. This review comprehensively summarizes the state of the art development of biofuels production by reported thermophilic microorganisms, and also concludes strategies to improve biofuels production including the metabolic pathways construction, co-culturing systems and biofuels tolerance. In addition, strategies to further improve butanol production are proposed.
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Affiliation(s)
- Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Jiasheng Lu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China
| | - Min Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Hao Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China
| | - Jiangfeng Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China.
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MARCO ÉVILINGDE, HECK KARINA, MARTOS EMERSONT, VAN DER SAND SUELIT. Purification and characterization of a thermostable alkaline cellulase produced by Bacillus licheniformis 380 isolated from compost. ACTA ACUST UNITED AC 2017; 89:2359-2370. [DOI: 10.1590/0001-3765201720170408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 06/28/2017] [Indexed: 01/14/2023]
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Wright TA, Lucius Dougherty M, Schmitz B, Burridge KM, Makaroff K, Stewart JM, Fischesser HD, Shepherd JT, Berberich JA, Konkolewicz D, Page RC. Polymer Conjugation to Enhance Cellulase Activity and Preserve Thermal and Functional Stability. Bioconjug Chem 2017; 28:2638-2645. [DOI: 10.1021/acs.bioconjchem.7b00518] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Thaiesha A. Wright
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Melissa Lucius Dougherty
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Benjamin Schmitz
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Kevin M. Burridge
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Katherine Makaroff
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Jamie M. Stewart
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Henry D. Fischesser
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Jerry T. Shepherd
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Jason A. Berberich
- Department
of Chemical, Paper, and Biomedical Engineering, 650 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Dominik Konkolewicz
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
| | - Richard C. Page
- Department
of Chemistry and Biochemistry, 651 East High Street, Miami University, Oxford, Ohio 45056 United States
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Hatefi A, Makhdoumi A, Asoodeh A, Mirshamsi O. Characterization of a bi-functional cellulase produced by a gut bacterial resident of Rosaceae branch borer beetle, Osphranteria coerulescens (Coleoptera: Cerambycidae). Int J Biol Macromol 2017; 103:158-164. [DOI: 10.1016/j.ijbiomac.2017.05.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 04/12/2017] [Accepted: 05/09/2017] [Indexed: 10/19/2022]
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Complete Genome Sequence of Geobacillus thermodenitrificans T12, A Potential Host for Biotechnological Applications. Curr Microbiol 2017; 75:49-56. [PMID: 28900693 PMCID: PMC5765199 DOI: 10.1007/s00284-017-1349-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/28/2017] [Indexed: 01/12/2023]
Abstract
In attempt to obtain a thermophilic host for the conversion of lignocellulose derived substrates into lactic acid, Geobacillus thermodenitrificans T12 was isolated from a compost heap. It was selected from over 500 isolates as a genetically tractable hemicellulolytic lactic acid producer, requiring little nutrients. The strain is able to ferment glucose and xylose simultaneously and can produce lactic acid from xylan, making it a potential host for biotechnological applications. The genome of strain T12 consists of a 3.64 Mb chromosome and two plasmids of 59 and 56 kb. It has a total of 3.676 genes with an average genomic GC content of 48.7%. The T12 genome encodes a denitrification pathway, allowing for anaerobic respiration. The identity and localization of the responsible genes are similar to those of the denitrification pathways found in strain NG80-2. The hemicellulose utilization (HUS) locus was identified based on sequence homology against G. stearothermophilus T-6. It appeared that T12 has all the genes that are present in strain T-6 except for the arabinan degradation cluster. Instead, the HUS locus of strain T12 contains genes for both an inositol and a pectate degradation pathway. Strain T12 has complete pathways for the synthesis of purine and pyrimidine, all 20 amino acids and several vitamins except D-biotin. The host-defense systems present comprise a Type II and a Type III restriction-modification system, as well as a CRISPR-Cas Type II system. It is concluded that G. thermodenitrificans T12 is a potentially interesting candidate for industrial applications.
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Azadian F, Badoei-dalfard A, Namaki-Shoushtari A, Karami Z, Hassanshahian M. Production and characterization of an acido-thermophilic, organic solvent stable cellulase from Bacillus sonorensis HSC7 by conversion of lignocellulosic wastes. J Genet Eng Biotechnol 2017; 15:187-196. [PMID: 30647655 PMCID: PMC6296611 DOI: 10.1016/j.jgeb.2016.12.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 11/15/2016] [Accepted: 12/19/2016] [Indexed: 01/06/2023]
Abstract
The acidophilic and thermophilic cellulase would facilitate the conversion of lignocellulosic biomass to biofuel. In this study, Bacillus sonorensis HSC7 isolated as the best thermophilic cellulose degrading bacterium from Gorooh hot spring. 16S rRNA gene sequencing showed that, this strain closely related to the B. sonorensis. CMCase production was considered under varying environmental parameters. Results showed that, sucrose and (NH4)2SO4 were obtained as the best carbon and nitrogen sources for CMCase production. B. sonorensis HSC7 produced CMCase during the growth in optimized medium supplemented with agricultural wastes as sole carbon sources. The enzyme was active with optimum temperature of 70 °C and the optimum CMCase activity and stability observed at pH 4.0 and 5.0, respectively. These are characteristics indicating that, this enzyme could be an acidophilic and thermophilic CMCase. Furthermore, the CMCase activity improved by methanol (166%), chloroform (152%), while it was inhibited by DMF (61%). The CMCase activity was enhanced in the presence of Mg+2 (110%), Cu+2 (116%), Triton X-100 (118%) and it retained 57% of its activity at 30% NaCl. The compatibility of HSC7 CMCase varied for each laundry detergent, with higher stability being observed in the presence of Taj® and darya®. This enzyme, that is able to work under extreme conditions, has potential applications in various industries.
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Affiliation(s)
| | - Arastoo Badoei-dalfard
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran
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Piceno YM, Pecora-Black G, Kramer S, Roy M, Reid FC, Dubinsky EA, Andersen GL. Bacterial community structure transformed after thermophilically composting human waste in Haiti. PLoS One 2017; 12:e0177626. [PMID: 28570610 PMCID: PMC5453478 DOI: 10.1371/journal.pone.0177626] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 05/01/2017] [Indexed: 11/19/2022] Open
Abstract
Recycling human waste for beneficial use has been practiced for millennia. Aerobic (thermophilic) composting of sewage sludge has been shown to reduce populations of opportunistically pathogenic bacteria and to inactivate both Ascaris eggs and culturable Escherichia coli in raw waste, but there is still a question about the fate of most fecal bacteria when raw material is composted directly. This study undertook a comprehensive microbial community analysis of composting material at various stages collected over 6 months at two composting facilities in Haiti. The fecal microbiota signal was monitored using a high-density DNA microarray (PhyloChip). Thermophilic composting altered the bacterial community structure of the starting material. Typical fecal bacteria classified in the following groups were present in at least half the starting material samples, yet were reduced below detection in finished compost: Prevotella and Erysipelotrichaceae (100% reduction of initial presence), Ruminococcaceae (98–99%), Lachnospiraceae (83–94%, primarily unclassified taxa remained), Escherichia and Shigella (100%). Opportunistic pathogens were reduced below the level of detection in the final product with the exception of Clostridium tetani, which could have survived in a spore state or been reintroduced late in the outdoor maturation process. Conversely, thermotolerant or thermophilic Actinomycetes and Firmicutes (e.g., Thermobifida, Bacillus, Geobacillus) typically found in compost increased substantially during the thermophilic stage. This community DNA-based assessment of the fate of human fecal microbiota during thermophilic composting will help optimize this process as a sanitation solution in areas where infrastructure and resources are limited.
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Affiliation(s)
- Yvette M. Piceno
- Ecology Department, Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, United States of America
| | - Gabrielle Pecora-Black
- Agricultural & Environmental Chemistry Graduate Group, University of California, Davis, CA, United States of America
| | - Sasha Kramer
- Sustainable Organic Integrated Livelihoods, Port-au-Prince, Haiti
| | - Monika Roy
- Sustainable Organic Integrated Livelihoods, Port-au-Prince, Haiti
| | - Francine C. Reid
- Ecology Department, Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, United States of America
| | - Eric A. Dubinsky
- Ecology Department, Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, United States of America
| | - Gary L. Andersen
- Ecology Department, Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, United States of America
- * E-mail:
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Escherichia coli expressing endoglucanase gene from Thai higher termite bacteria for enzymatic and microbial hydrolysis of cellulosic materials. ELECTRON J BIOTECHN 2017. [DOI: 10.1016/j.ejbt.2017.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Adıgüzel AO, Tunçer M. Production, purification, characterization and usage of a detergent additive of endoglucanase from isolated halotolerant Amycolatopsis cihanbeyliensis mutated strain Mut43. BIOCATAL BIOTRANSFOR 2017. [DOI: 10.1080/10242422.2017.1315106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Ali Osman Adıgüzel
- Faculty of Sciences and Letters, Department of Biology, Microbiology Laboratory, Mersin University, Mersin, Turkey
| | - Münir Tunçer
- Faculty of Sciences and Letters, Department of Biology, Microbiology Laboratory, Mersin University, Mersin, Turkey
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Characterization of a thermophilic cellulase from Geobacillus sp. HTA426, an efficient cellulase-producer on alkali pretreated of lignocellulosic biomass. PLoS One 2017; 12:e0175004. [PMID: 28406925 PMCID: PMC5390992 DOI: 10.1371/journal.pone.0175004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 03/17/2017] [Indexed: 11/19/2022] Open
Abstract
A themophilic cellulase-producing bacterium was isolated from a hot spring district and identified as Geobacillus sp. HTA426. The cellulase enzyme produced by the Geobacillus sp. HTA426 was purified through ammonium sulfate precipitation and ion exchange chromatography, with the recovery yield and fold purification of 10.14% and 5.12, respectively. The purified cellulase has a molecular weight of 40 kDa. The optimum temperature and pH for carboxymethyl cellulase (CMCase) activity of the purified cellulase were 60°C and pH 7.0, respectively. The enzyme was also stable over a wide temperature range of 50°C to 70°C after 5 h of incubation. Moreover, the strain HTA426 was able to grow and produce cellulase on alkali-treated sugarcane bagasse, rice straw and water hyacinth as carbon sources. Enzymatic hydrolysis of sugarcane bagasse, which was regarded as the most effective carbon source for cellulase production (CMCase activity = 103.67 U/mL), followed by rice straw (74.70 U/mL) and water hyacinth (51.10 U/mL). This strain producing an efficient thermostable cellulose is a potential candidate for developing a more efficient and cost-effective process for converting lignocellulosic biomass into biofuel and other industrial process.
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Wilhelm RC, Cardenas E, Leung H, Szeitz A, Jensen LD, Mohn WW. Long-Term Enrichment of Stress-Tolerant Cellulolytic Soil Populations following Timber Harvesting Evidenced by Multi-Omic Stable Isotope Probing. Front Microbiol 2017; 8:537. [PMID: 28443069 PMCID: PMC5386986 DOI: 10.3389/fmicb.2017.00537] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 03/14/2017] [Indexed: 12/23/2022] Open
Abstract
Soil management is vital for maintaining the productivity of commercial forests, yet the long-term impact of timber harvesting on soil microbial communities remains largely a matter of conjecture. Decomposition of plant biomass, comprised mainly of lignocellulose, has a broad impact on nutrient cycling, microbial activity and physicochemical characteristics of soil. At "Long-term Soil Productivity Study" sites in California dominated by Ponderosa pine, we tested whether clear-cut timber harvesting, accompanied by varying degrees of organic matter (OM) removal, affected the activity and structure of the cellulose-degrading microbial populations 16 years after harvesting. Using a variety of experimental approaches, including stable isotope probing with 13C-labeled cellulose in soil microcosms, we demonstrated that harvesting led to a decrease in net respiration and cellulolytic activity. The decrease in cellulolytic activity was associated with an increased relative abundance of thermophilic, cellulolytic fungi (Chaetomiaceae), coupled with a decreased relative abundance of cellulolytic bacteria, particularly members of Opitutaceae, Caulobacter, and Streptomycetaceae. In general, harvesting led to an increase in stress-tolerant taxa (i.e., also non-cellulolytic taxa), though our results indicated that OM retention mitigated population shifts via buffering against abiotic changes. Stable-isotope probing improved shotgun metagenome assembly by 20-fold and enabled the recovery of 10 metagenome-assembled genomes of cellulolytic bacteria and fungi. Our study demonstrates the putative cellulolytic activity of a number of uncultured taxa and highlights the mineral soil layer as a reservoir of uncharacterized diversity of cellulose-degraders. It also and contributes to a growing body of research showing persistent changes in microbial community structure in the decades following forest harvesting.
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Affiliation(s)
- Roland C. Wilhelm
- Department of Microbiology and Immunology, Life Sciences Institute, University of British ColumbiaVancouver, BC, Canada
| | - Erick Cardenas
- Department of Microbiology and Immunology, Life Sciences Institute, University of British ColumbiaVancouver, BC, Canada
| | - Hilary Leung
- Department of Microbiology and Immunology, Life Sciences Institute, University of British ColumbiaVancouver, BC, Canada
| | - András Szeitz
- Pharmaceutical Analytical Suite, Faculty of Pharmaceutical Sciences, University of British ColumbiaVancouver, BC, Canada
| | - Lionel D. Jensen
- Department of Microbiology and Immunology, Life Sciences Institute, University of British ColumbiaVancouver, BC, Canada
| | - William W. Mohn
- Department of Microbiology and Immunology, Life Sciences Institute, University of British ColumbiaVancouver, BC, Canada
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80
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Kazeem MO, Shah UKM, Baharuddin AS, AbdulRahman NA. Prospecting Agro-waste Cocktail: Supplementation for Cellulase Production by a Newly Isolated Thermophilic B. licheniformis 2D55. Appl Biochem Biotechnol 2017; 182:1318-1340. [PMID: 28176140 PMCID: PMC5534209 DOI: 10.1007/s12010-017-2401-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/09/2017] [Indexed: 01/17/2023]
Abstract
Bacteria isolated from thermophilic environment that can produce cellulase as well as utilise agro-waste biomass have a high potential for developing thermostable cellulase required in the biofuel industry. The cost for cellulase represents a significant challenge in converting lignocellulose to fermentable sugars for biofuel production. Among three potential bacteria examined, Bacillus licheniformis 2D55 (accession no. KT799651) was found to produce the highest cellulolytic activity (CMCase 0.33 U/mL and FPase 0.09 U/mL) at 18–24 h fermentation when grown on microcrystalline cellulose (MCC) as a carbon source in shake flask at 50 °C. Cellulase production process was further conducted on the untreated and NaOH pretreated rice straw (RS), rice husk (RH), sugarcane bagasse (BAG) and empty fruit bunch (EFB). Untreated BAG produced the highest FPase (0.160 U/mL), while the highest CMCase (0.150 U/mL) was supported on the pretreated RH. The mixture of untreated BAG and pretreated RH as agro-waste cocktail has remarkably improved CMCase (3.7- and 1.4-fold) and FPase (2.5- and 11.5-fold) compared to the untreated BAG and pretreated RH, respectively. The mechanism of cellulase production explored through SEM analysis and the location of cellulase enzymes of the isolate was also presented. Agro-waste cocktail supplementation provides an alternative method for an efficient production of cellulase.
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Affiliation(s)
- Muinat Olanike Kazeem
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.,Department of Microbiology, Faculty of Life Sciences, University of Ilorin, Ilorin, Kwara State, 1515, Nigeria
| | - Umi Kalsom Md Shah
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Azhari Samsu Baharuddin
- Department of Process and Food Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - Nor' Aini AbdulRahman
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
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81
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Pogrebnyakov I, Jendresen CB, Nielsen AT. Genetic toolbox for controlled expression of functional proteins in Geobacillus spp. PLoS One 2017; 12:e0171313. [PMID: 28152017 PMCID: PMC5289569 DOI: 10.1371/journal.pone.0171313] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 01/19/2017] [Indexed: 11/20/2022] Open
Abstract
Species of genus Geobacillus are thermophilic bacteria and play an ever increasing role as hosts for biotechnological applications both in academia and industry. Here we screened a number of Geobacillus strains to determine which industrially relevant carbon sources they can utilize. One of the strains, G. thermoglucosidasius C56-YS93, was then chosen to develop a toolbox for controlled gene expression over a wide range of levels. It includes a library of semi-synthetic constitutive promoters (76-fold difference in expression levels) and an inducible promoter from the xylA gene. A library of synthetic in silico designed ribosome binding sites was also created for further tuning of translation. The PxylA was further used to successfully express native and heterologous xylanases in G. thermoglucosidasius. This toolbox enables fine-tuning of gene expression in Geobacillus species for metabolic engineering approaches in production of biochemicals and heterologous proteins.
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Affiliation(s)
- Ivan Pogrebnyakov
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Christian Bille Jendresen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Alex Toftgaard Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark
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82
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Irfan M, Tayyab A, Hasan F, Khan S, Badshah M, Shah AA. Production and Characterization of Organic Solvent-Tolerant Cellulase from Bacillus amyloliquefaciens AK9 Isolated from Hot Spring. Appl Biochem Biotechnol 2017; 182:1390-1402. [DOI: 10.1007/s12010-017-2405-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 01/11/2017] [Indexed: 10/20/2022]
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83
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Azizi M, Hemmat J, Seifati SM, Torktaz I, Karimi S. Characterization of a thermostable endoglucanase produced by Isoptericola variabilis sp. IDAH9. Braz J Microbiol 2016; 46:1225-34. [PMID: 26691485 PMCID: PMC4704623 DOI: 10.1590/s1517-838246420140846] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 03/21/2015] [Indexed: 01/04/2023] Open
Abstract
This study aimed to isolate and evaluate the cellulase activity of cellulolytic
bacteria in hot springs of Dehloran, Ilam province, Iran. Water and sludge samples
were collected from the hot springs and the bacterial enrichment was performed in a
medium containing rice barn and carboxymethyl cellulose (CMC). The cultures were
incubated at 50 °C in aerobic conditions. The bacteria were isolated on CMC agar (1%)
medium. Cellulase assay of the isolates was measured by the evaluation of
endoglucanase enzyme activity, which is also called as carboxymethyl cellulase
(CMCase). The isolated thermotolerant bacteria were then identified and optimized for
the production of CMCase. Moreover, stabilizing elements of the enzyme were
identified with in silico approach. The chosen isolate was
identified as Isoptericola variabilis sp. IDAH9. The identified
strain produced the most thermostable CMCase at a concentration of 5.6 g/L of
ammonium sulfate, 9 g/L CMCase or 12 g/L rice bran, 0/6% Tween-80, and 0.2% sucrose.
The produced enzyme showed 80% of the residual activity after 1 h of incubation at 65
°C. In silico data indicated that the remaining residual activity
was due to the redundant stabilizing elements in the protein structure. Consequently,
I. variabilis can be isolated from the extreme environment and
has a thermostable endoglucanase which may be used for various applications after
studying them.
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Affiliation(s)
- Maryam Azizi
- Biotechnology Department, Iranian Research Organization for Science and Technology, Tehran, Iran
| | - Jafar Hemmat
- Biotechnology Department, Iranian Research Organization for Science and Technology, Tehran, Iran
| | | | - Ibrahim Torktaz
- Biotechnology Department, Iranian Research Organization for Science and Technology, Tehran, Iran
| | - Soodabeh Karimi
- Biotechnology Department, Iranian Research Organization for Science and Technology, Tehran, Iran
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84
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Trivedi N, Reddy CRK, Lali AM. Marine Microbes as a Potential Source of Cellulolytic Enzymes. ADVANCES IN FOOD AND NUTRITION RESEARCH 2016; 79:27-41. [PMID: 27770862 DOI: 10.1016/bs.afnr.2016.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Marine environment hosts the wide range of habitats with remarkably high and diverse microbial populations. The ability of marine microorganisms to survive in extreme temperature, salinity, and pressure depends on the function of multivarious enzyme systems that in turn provide vast potential for biotechnological exploration studies. Therefore, the enzymes from marine microorganism represent novel bio catalytic potential with stable and reliable properties. Microbial cellulases constitute a major group of industrial enzymes that find applications in various industries. Majority of cellulases are of terrestrial origin, and very limited research has been carried out to explore marine microbes as a source of cellulases. This chapter presents an overview about the types of marine polysaccharases, classification and potential applications of cellulases, different sources of marine cellulases, and their future perspectives.
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Affiliation(s)
- N Trivedi
- Division of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - C R K Reddy
- Division of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India.
| | - A M Lali
- DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Mumbai, India
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85
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Goswami R, Mukherjee S, Chakraborty AK, Balachandran S, Sinha Babu SP, Chaudhury S. Optimization of growth determinants of a potent cellulolytic bacterium isolated from lignocellulosic biomass for enhancing biogas production. CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY 2016; 18:1565-1583. [DOI: 10.1007/s10098-016-1141-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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86
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Behera SS, Ray RC. Solid state fermentation for production of microbial cellulases: Recent advances and improvement strategies. Int J Biol Macromol 2016; 86:656-69. [DOI: 10.1016/j.ijbiomac.2015.10.090] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 12/23/2022]
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87
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Cellulolytic Activity of Thermophilic Bacilli Isolated from Tattapani Hot Spring Sediment in North West Himalayas. Indian J Microbiol 2016; 56:228-231. [PMID: 27570317 DOI: 10.1007/s12088-016-0578-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 03/25/2016] [Indexed: 10/22/2022] Open
Abstract
Eight thermophilic bacterial strains were isolated from Tattapani Hot spring and screened for various hydrolytic enzymes including cellulases. The isolated bacterial strains were identified as Geobacillus thermodenitrificans IP_WH1(KP842609), Bacillus licheniformis IP_WH2(KP842610), B. aerius IP_WH3(KP842611), B. licheniformis IP_WH4(KP842612), B. licheniformis IP_60Y(KP842613), G. thermodenitrificans IP_60A1(KP842614), Geobacillus sp. IP_60A2(KP842615) and Geobacillus sp. IP_80TP(KP842616) after 16S ribotying. Out of the eight isolates Geobacillus sp. IP_80TP grew best at 80 °C whereas rest of the isolates showed optimal growth at 60 °C. G. thermodenitrificans IP_WH1 produced a thermotolerant cellulase with maximum activity at 60 °C.
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88
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Chang CJ, Lee CC, Chan YT, Trudeau DL, Wu MH, Tsai CH, Yu SM, Ho THD, Wang AHJ, Hsiao CD, Arnold FH, Chao YC. Exploring the Mechanism Responsible for Cellulase Thermostability by Structure-Guided Recombination. PLoS One 2016; 11:e0147485. [PMID: 26986867 PMCID: PMC4795783 DOI: 10.1371/journal.pone.0147485] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 01/05/2016] [Indexed: 12/29/2022] Open
Abstract
Cellulases from Bacillus and Geobacillus bacteria are potentially useful in the biofuel and animal feed industries. One of the unique characteristics of these enzymes is that they are usually quite thermostable. We previously identified a cellulase, GsCelA, from thermophilic Geobacillus sp. 70PC53, which is much more thermostable than its Bacillus homolog, BsCel5A. Thus, these two cellulases provide a pair of structures ideal for investigating the mechanism regarding how these cellulases can retain activity at high temperature. In the present study, we applied the SCHEMA non-contiguous recombination algorithm as a novel tool, which assigns protein sequences into blocks for domain swapping in a way that lessens structural disruption, to generate a set of chimeric proteins derived from the recombination of GsCelA and BsCel5A. Analyzing the activity and thermostability of this designed library set, which requires only a limited number of chimeras by SCHEMA calculations, revealed that one of the blocks may contribute to the higher thermostability of GsCelA. When tested against swollen Avicel, the highly thermostable chimeric cellulase C10 containing this block showed significantly higher activity (22%-43%) and higher thermostability compared to the parental enzymes. With further structural determinations and mutagenesis analyses, a 310 helix was identified as being responsible for the improved thermostability of this block. Furthermore, in the presence of ionic calcium and crown ether (CR), the chimeric C10 was found to retain 40% residual activity even after heat treatment at 90°C. Combining crystal structure determinations and structure-guided SCHEMA recombination, we have determined the mechanism responsible for the high thermostability of GsCelA, and generated a novel recombinant enzyme with significantly higher activity.
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Affiliation(s)
- Chia-Jung Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Cheng-Chung Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
- Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei, Taiwan, ROC
| | - Yueh-Te Chan
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
- Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei, Taiwan, ROC
| | - Devin L. Trudeau
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, United States of America
| | - Mei-Huey Wu
- Institute of Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Chih-Hsuan Tsai
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Tuan-Hua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Andrew H.-J. Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
- Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei, Taiwan, ROC
| | - Chwan-Deng Hsiao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, United States of America
| | - Yu-Chan Chao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
- * E-mail:
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89
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Manfredi AP, Pisa JH, Valdeón DH, Perotti NI, Martínez MA. Synergistic Effect of Simple Sugars and Carboxymethyl Cellulose on the Production of a Cellulolytic Cocktail from Bacillus sp. AR03 and Enzyme Activity Characterization. Appl Biochem Biotechnol 2016; 179:16-32. [DOI: 10.1007/s12010-015-1976-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/29/2015] [Indexed: 11/27/2022]
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90
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Gomes E, de Souza AR, Orjuela GL, Da Silva R, de Oliveira TB, Rodrigues A. Applications and Benefits of Thermophilic Microorganisms and Their Enzymes for Industrial Biotechnology. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27951-0_21] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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91
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Budihal SR, Agsar D, Patil SR. Enhanced production and application of acidothermophilic Streptomyces cellulase. BIORESOURCE TECHNOLOGY 2016; 200:706-712. [PMID: 26556405 DOI: 10.1016/j.biortech.2015.10.098] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 10/29/2015] [Accepted: 10/30/2015] [Indexed: 06/05/2023]
Abstract
An efficient cellulolytic and acidothermophilic actinobacterium was isolated from soil, adhered to decomposing tree bark and was identified as Streptomyces DSK59. Screening of synthetic media and the media components identified that, a medium based on starch casein minerals containing carboxy methyl cellulose (CMC) and beef extract (BE) could support enhanced cellulase production by the organism. CMC, BE, NaCl, temperature and pH were accounted as significant for cellulase production and these were optimized using a response surface central composite design (CCD). Optimization of cellulase production resulted in an enhancement of endoglucanase activity to 27IUml(-1). Acidothermophillic Streptomyces cellulase was found to be efficient for hydrolysis of pretreated sorghum stover and liberated 0.413gg(-1) of total reducing sugars which was higher than previously reported sugar yields obtained using fungal enzymes.
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Affiliation(s)
- Saikumar R Budihal
- A-DBT Research Laboratory, Department of Microbiology, Gulbarga University, Kalaburagi 585106, India
| | - Dayanand Agsar
- A-DBT Research Laboratory, Department of Microbiology, Gulbarga University, Kalaburagi 585106, India.
| | - Sarvamangala R Patil
- Department of Biotechnology, Vishweshwariah College of Applied Sciences, Kalaburagi 585103, India
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92
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Daas MJA, van de Weijer AHP, de Vos WM, van der Oost J, van Kranenburg R. Isolation of a genetically accessible thermophilic xylan degrading bacterium from compost. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:210. [PMID: 27752284 PMCID: PMC5053077 DOI: 10.1186/s13068-016-0618-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 09/20/2016] [Indexed: 05/20/2023]
Abstract
BACKGROUND Due to the finite nature of global oil resources we are now faced with the challenge of finding renewable resources to produce fuels and chemicals in the future. Lactic acid has great potential as a precursor for the production of bioplastics alternatives to conventional plastics. Efficient lactic acid fermentation from non-food lignocellulosic substrates requires pretreatment and saccharification to generate fermentable sugars. A fermentation process that requires little to no enzyme additions, i.e. consolidated bioprocessing would be preferred and requires lactic acid-producing organisms that have cellulolytic and/or hemicellulolytic activity. RESULTS To obtain candidate production strains we have enriched and isolated facultative anaerobic (hemi) cellulolytic bacterial strains from compost samples. By selecting for growth on both cellulose and xylan, 94 Geobacillus strains were isolated. Subsequent screening for lactic acid production was carried out from C6 and C5 sugar fermentations and a selection of the best lactic acid producers was made. The denitrifying Geobacillus thermodenitrificans T12 was selected for further research and was rendered genetically accessible. In fermentations on a mixture of glucose and xylose, a total of 20.3 g of lactic acid was produced with a yield of 0.94 g product/g sugar consumed. In addition, strain T12 is capable of direct conversion of beech wood xylan to mainly lactic acid in minimal media. CONCLUSIONS We have demonstrated that G. thermodenitrificans T12 is genetically accessible and produces lactic acid as its main fermentation product on glucose, xylose and a mixture thereof. Strain T12 was additionally used for the direct conversion of xylan to lactic acid. The genetic accessibility of the T12 strain provides a solid basis for the development of this strain into a host for consolidated bioprocessing of biomass to lactic acid.
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Affiliation(s)
- Martinus J. A. Daas
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | | | - Willem M. de Vos
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
- Corbion, Arkselsedijk 46, 4206 AC Gorinchem, The Netherlands
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93
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Wang C, Dong D, Wang H, Müller K, Qin Y, Wang H, Wu W. Metagenomic analysis of microbial consortia enriched from compost: new insights into the role of Actinobacteria in lignocellulose decomposition. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:22. [PMID: 26834834 PMCID: PMC4731972 DOI: 10.1186/s13068-016-0440-2] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 01/14/2016] [Indexed: 05/18/2023]
Abstract
BACKGROUND Compost habitats sustain a vast ensemble of microbes specializing in the degradation of lignocellulosic plant materials and are thus important both for their roles in the global carbon cycle and as potential sources of biochemical catalysts for advanced biofuels production. Studies have revealed substantial diversity in compost microbiomes, yet how this diversity relates to functions and even to the genes encoding lignocellulolytic enzymes remains obscure. Here, we used a metagenomic analysis of the rice straw-adapted (RSA) microbial consortia enriched from compost ecosystems to decipher the systematic and functional contexts within such a distinctive microbiome. RESULTS Analyses of the 16S pyrotag library and 5 Gbp of metagenomic sequence showed that the phylum Actinobacteria was the predominant group among the Bacteria in the RSA consortia, followed by Proteobacteria, Firmicutes, Chloroflexi, and Bacteroidetes. The CAZymes profile revealed that CAZyme genes in the RSA consortia were also widely distributed within these bacterial phyla. Strikingly, about 46.1 % of CAZyme genes were from actinomycetal communities, which harbored a substantially expanded catalog of the cellobiohydrolase, β-glucosidase, acetyl xylan esterase, arabinofuranosidase, pectin lyase, and ligninase genes. Among these communities, a variety of previously unrecognized species was found, which reveals a greater ecological functional diversity of thermophilic Actinobacteria than previously assumed. CONCLUSION These data underline the pivotal role of thermophilic Actinobacteria in lignocellulose biodegradation processes in the compost habitat. Besides revealing a new benchmark for microbial enzymatic deconstruction of lignocelluloses, the results suggest that actinomycetes found in compost ecosystems are potential candidates for mining efficient lignocellulosic enzymes in the biofuel industry.
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Affiliation(s)
- Cheng Wang
- />Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology, Institute of Environmental Science and Technology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China
| | - Da Dong
- />Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology, Institute of Environmental Science and Technology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China
- />Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, School of Environmental and Resource Sciences, Zhejiang A & F University, Lin’an, Hangzhou, 311300 China
| | - Haoshu Wang
- />Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology, Institute of Environmental Science and Technology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China
| | - Karin Müller
- />Ruakura Research Centre, The New Zealand Institute for Plant and Food Research Limited, Private Bag 3123, Hamilton, New Zealand
| | - Yong Qin
- />Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology, Institute of Environmental Science and Technology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China
| | - Hailong Wang
- />Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, School of Environmental and Resource Sciences, Zhejiang A & F University, Lin’an, Hangzhou, 311300 China
| | - Weixiang Wu
- />Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology, Institute of Environmental Science and Technology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058 China
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94
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Premalatha N, Gopal NO, Jose PA, Anandham R, Kwon SW. Optimization of cellulase production by Enhydrobacter sp. ACCA2 and its application in biomass saccharification. Front Microbiol 2015; 6:1046. [PMID: 26500615 PMCID: PMC4597110 DOI: 10.3389/fmicb.2015.01046] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/14/2015] [Indexed: 11/13/2022] Open
Abstract
Cellulase finds use in saccharification of lignocellulosic agroresidues to fermentable sugars which can be used for production of commercially important metabolites. This study reports endoglucanase (CMCase) production by Enhydrobacter sp. ACCA2. The CMCase activity of the strain ACCA2 was successively improved by optimization of range of physical and nutritional parameter in a set of non-statistical and statistical experiments. Initial non-statistical selection of carbon source, incubation time, temperature and pH resulted in 1.07 fold increase of CMCase activity. In a subsequent statistical method, response surface methodology, optimization of medium components such as carboxymethylcellulose, peptone, NaCl, MgSO4, K2HPO4, and (NH4)2SO4 yielded further increase up to 2.39 fold CMCase activity. The cellulolytic potential was evaluated in biomass saccharification with different plant materials and the results revealed that the enzyme produced by strain may have significant commercial values for industrial saccharification process. Moreover, this is the first report of cellulase production by an Enhydrobacter spp.
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Affiliation(s)
- Nagaiah Premalatha
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Nellaiappan O Gopal
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Polpass Arul Jose
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Rangasamy Anandham
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Soon-Wo Kwon
- Korean Agricultural Culture Collection, National Academy of Agricultural Science, Rural Development Administration Jeonju, South Korea
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95
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High yield expression of novel glutaminase free l-asparaginase II of Pectobacterium carotovorum MTCC 1428 in Bacillus subtilis WB800N. Bioprocess Biosyst Eng 2015; 38:2271-84. [DOI: 10.1007/s00449-015-1464-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/20/2015] [Indexed: 10/23/2022]
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96
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Prospection and Evaluation of (Hemi) Cellulolytic Enzymes Using Untreated and Pretreated Biomasses in Two Argentinean Native Termites. PLoS One 2015; 10:e0136573. [PMID: 26313257 PMCID: PMC4552170 DOI: 10.1371/journal.pone.0136573] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 08/04/2015] [Indexed: 01/30/2023] Open
Abstract
Saccharum officinarum bagasse (common name: sugarcane bagasse) and Pennisetum purpureum (also known as Napier grass) are among the most promising feedstocks for bioethanol production in Argentina and Brazil. In this study, both biomasses were assessed before and after acid pretreatment and following hydrolysis with Nasutitermes aquilinus and Cortaritermes fulviceps termite gut digestome. The chemical composition analysis of the biomasses after diluted acid pretreatment showed that the hemicellulose fraction was partially removed. The (hemi) cellulolytic activities were evaluated in bacterial culture supernatants of termite gut homogenates grown in treated and untreated biomasses. In all cases, we detected significantly higher endoglucanase and xylanase activities using pretreated biomasses compared to untreated biomasses, carboxymethylcellulose and xylan. Several protein bands with (hemi) cellulolytic activity were detected in zymograms and two-dimensional gel electrophoresis. Some proteins of these bands or spots were identified as xylanolytic peptides by mass spectrometry. Finally, the diversity of cultured cellulolytic bacterial endosymbionts associated to both Argentinean native termite species was analyzed. This study describes, for the first time, bacterial endosymbionts and endogenous (hemi) cellulases of two Argentinean native termites as well as their potential application in degradation of lignocellulosic biomass for bioethanol production.
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97
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Paudel YP, Qin W. Characterization of Novel Cellulase-producing Bacteria Isolated From Rotting Wood Samples. Appl Biochem Biotechnol 2015; 177:1186-98. [DOI: 10.1007/s12010-015-1806-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/10/2015] [Indexed: 11/30/2022]
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98
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Xue DS, Wang JB, Yao SJ. High production of β-glucosidase from a marine Aspergillus niger immobilized on towel gourd vegetable sponges. CHINESE CHEM LETT 2015. [DOI: 10.1016/j.cclet.2015.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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99
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Bhalla A, Bischoff KM, Sani RK. Highly Thermostable Xylanase Production from A Thermophilic Geobacillus sp. Strain WSUCF1 Utilizing Lignocellulosic Biomass. Front Bioeng Biotechnol 2015; 3:84. [PMID: 26137456 PMCID: PMC4468944 DOI: 10.3389/fbioe.2015.00084] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/22/2015] [Indexed: 01/04/2023] Open
Abstract
Efficient enzymatic hydrolysis of lignocellulose to fermentable sugars requires a complete repertoire of biomass deconstruction enzymes. Hemicellulases play an important role in hydrolyzing hemicellulose component of lignocellulose to xylooligosaccharides and xylose. Thermostable xylanases have been a focus of attention as industrially important enzymes due to their long shelf life at high temperatures. Geobacillus sp. strain WSUCF1 produced thermostable xylanase activity (crude xylanase cocktail) when grown on xylan or various inexpensive untreated and pretreated lignocellulosic biomasses such as prairie cord grass and corn stover. The optimum pH and temperature for the crude xylanase cocktail were 6.5 and 70°C, respectively. The WSUCF1 crude xylanase was found to be highly thermostable with half-lives of 18 and 12 days at 60 and 70°C, respectively. At 70°C, rates of xylan hydrolysis were also found to be better with the WSUCF1 secretome than those with commercial enzymes, i.e., for WSUCF1 crude xylanase, Cellic-HTec2, and AccelleraseXY, the percent xylan conversions were 68.9, 49.4, and 28.92, respectively. To the best of our knowledge, WSUCF1 crude xylanase cocktail is among the most thermostable xylanases produced by thermophilic Geobacillus spp. and other thermophilic microbes (optimum growth temperature ≤70°C). High thermostability, activity over wide range of temperatures, and better xylan hydrolysis than commercial enzymes make WSUCF1 crude xylanase suitable for thermophilic lignocellulose bioconversion processes.
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Affiliation(s)
- Aditya Bhalla
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology , Rapid City, SD , USA
| | - Kenneth M Bischoff
- Renewable Product Technology Research Unit, Agricultural Research Service, National Center for Agricultural Utilization Research, U.S. Department of Agriculture , Peoria, IL , USA
| | - Rajesh Kumar Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology , Rapid City, SD , USA
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100
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Analysis of enzymes of the hemicellulose complex from Geobacillus stearothermophilus 22 VKPM B-11678 isolated from Garga hot spring, Russia. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.molcatb.2015.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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