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Hu L, Zhang S, Chai S, Lyu Y, Wang S, Feng Z. Discovery of two bifunctional/multifunctional cellulases by functional metagenomics. Enzyme Microb Technol 2023; 169:110288. [PMID: 37467538 DOI: 10.1016/j.enzmictec.2023.110288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/12/2023] [Accepted: 07/11/2023] [Indexed: 07/21/2023]
Abstract
Cellulases are widely used in industry, and the usage in bioconversion of biofuels makes cellulases more valuable. In this study, two tandem genes that encoded cellulases ZF994-1 and ZF994-2, respectively, were identified on a cosmid from a soil metagenomic library. Phylogenetic analysis indicated that ZF994-1 and ZF994-2 belonged to glycoside hydrolase family 12 (GH12), and GH3, respectively. Based on the substrate specificity analysis, the recombinant ZF994-1 exhibited weak endoglucanase activity, moderate β-1,3-glucanase and β-1,4-mannanase activities, and strong β-glucosidase activity, while the recombinant ZF994-2 exhibited moderate endoglucanase activity and strong β-glucosidase activity. More than 45% β-glucosidase activity of the recombinant ZF994-1 retained in the buffer containing 3 M glucose, indicating the good tolerance against glucose. The recombinant ZF994-2 showed high activity in the presence of metal ions and organic reagents, exhibiting potential industrial applications.
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Affiliation(s)
- Lingzhi Hu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Shengxia Zhang
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Shumao Chai
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Yunbin Lyu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Shaochen Wang
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Zhiyang Feng
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China.
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Meng Z, Yang C, Leng J, Zhu W, Cheng Y. Production, purification, characterization and application of two novel endoglucanases from buffalo rumen metagenome. J Anim Sci Biotechnol 2023; 14:16. [PMID: 36740711 PMCID: PMC9900955 DOI: 10.1186/s40104-022-00814-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 12/02/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Lignocellulose biomass is the most abundant and renewable material in nature. The objectives of this study were to characterize two endoglucanases TrepCel3 and TrepCel4, and determine the effect of the combination of them (1.2 mg TrepCel3, 0.8 mg TrepCel4) on in vitro rumen fermentation characteristics. In this study, three nature lignocellulosic substrates (rice straw, RS; wheat straw, WS; leymus chinensis, LC) were evaluated for their in vitro digestibility, gas, NH3-N and volatile fatty acid (VFA) production, and microbial protein (MCP) synthesis by adding enzymatic combination. METHODS Two endoglucanases' genes were successfully expressed in Escherichia coli (E. coli) BL21 (DE3), and enzymatic characteristics were further characterized. The combination of TrepCel3 and TrepCel4 was incubated with lignocellulosic substrates to evaluate its hydrolysis ability. RESULTS The maximum enzymatic activity of TrepCel3 was determined at pH 5.0 and 40 °C, while TrepCel4 was at pH 6.0 and 50 °C. They were stable over the temperature range of 30 to 60 °C, and active within the pH range of 4.0 to 9.0. The TrepCel3 and TrepCel4 had the highest activity in lichenan 436.9 ± 8.30 and 377.6 ± 6.80 U/mg, respectively. The combination of TrepCel3 and TrepCel4 exhibited the highest efficiency at the ratio of 60:40. Compared to maximum hydrolysis of TrepCel3 or TrepCel4 separately, this combination was shown to have a superior ability to maximize the saccharification yield from lignocellulosic substrates up to 188.4% for RS, 236.7% for wheat straw WS, 222.4% for LC and 131.1% for sugar beet pulp (SBP). Supplemental this combination enhanced the dry matter digestion (DMD), gas, NH3-N and VFA production, and MCP synthesis during in vitro rumen fermentation. CONCLUSIONS The TrepCel3 and TrepCel4 exhibited the synergistic relationship (60:40) and significantly increased the saccharification yield of lignocellulosic substrates. The combination of them stimulated in vitro rumen fermentation of lignocellulosic substrates. This combination has the potential to be a feed additive to improve agricultural residues utilization in ruminants. If possible, in the future, experiments in vivo should be carried out to fully evaluate its effect.
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Affiliation(s)
- Zhenxiang Meng
- Laboratory of Gastrointestinal Microbiology, National Center for International Research On Animal Gut Nutrition, Nanjing Agricultural University, Nanjing, 210095, China
| | - Chengjian Yang
- Buffalo Research Institute, Chinese Academy of Agricultural, Nanning, 530000, China
| | - Jing Leng
- Key Laboratory of Animal Nutrition and Feed Science of Yunnan Province, Yunnan Agricultural University, Kunming, 650000, China
| | - Weiyun Zhu
- Laboratory of Gastrointestinal Microbiology, National Center for International Research On Animal Gut Nutrition, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yanfen Cheng
- Laboratory of Gastrointestinal Microbiology, National Center for International Research On Animal Gut Nutrition, Nanjing Agricultural University, Nanjing, 210095, China.
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Lin W, Liu L, Liang J, Tang X, Shi J, Zhang L, Wu P, Lan S, Wang S, Zhou Y, Chen X, Zhao Y, Chen X, Wu B, Guo L. Changes of endophytic microbial community in Rhododendron simsii roots under heat stress and its correlation with leaf physiological indicators. Front Microbiol 2022; 13:1006686. [PMID: 36466690 PMCID: PMC9712210 DOI: 10.3389/fmicb.2022.1006686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/01/2022] [Indexed: 08/05/2023] Open
Abstract
Introduction The response mechanism of Rhododendron simsii and its endophytic microorganism to heat stress is still unclear. Methods The light incubator was used to set the temperature gradients, and the control (CK) was (day/night: 14/10 h) 25/22°C, the moderate-heat-stress (MHS) was 35/30°C and the high-heat-stress (HHS) was 40/35°C. Results Compared with CK, MHS significantly increased the contents of malondialdehyde, hydrogen peroxide, proline, and soluble sugar, as well as the activities of catalase and peroxidase in leaf, while HHS increased the activities of ascorbate peroxidase, and decreased chlorophyll content. Compared with CK, MHS reduced soil available nitrogen (N) content. Both heat stress changed the endophytic microbial community structure in roots. MHS enriched Pezicula and Paracoccus, while HHS significantly enriched Acidothermus and Haliangium. The abundance of Pezicula positively correlated with the contents of chlorophyll a and proline in leaf, and negatively correlated with soil ammonium N content. The abundance of Pezicula and Haliangium positively correlated with soluble sugar and malondialdehyde contents, respectively. Conclusions Our results suggest that root endophytic microorganisms play an important role in helping Rhododendron resisting heat stress, mainly by regulating soil N content and plant physiological characteristics.
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Affiliation(s)
- Wei Lin
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lei Liu
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
| | - Jincheng Liang
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
| | - Xuexiao Tang
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
| | - Jie Shi
- State Key Laboratory of Hydraulic Engineering Simulation and Safety, School of Civil Engineering, Tianjin University, Tianjin, China
| | - Li Zhang
- College of Tropical Crops, Hainan University, Haikou, China
| | - Purui Wu
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
| | - Siren Lan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Shusheng Wang
- Lushan Botanical Garden, Jiangxi Province and Chinese Academy of Sciences, Lushan, China
| | - Yan Zhou
- Guizhou Botanical Garden, Guiyang, China
| | | | - Ying Zhao
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
| | - Xiang Chen
- Institute of Biology, Guizhou Academy of Sciences, Guiyang, China
| | - Binghua Wu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lijin Guo
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education/College of Forestry, Hainan University, Haikou, China
- International Magnesium Institute, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, China
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Seddouk L, Jamai L, Tazi K, Ettayebi M, Alaoui-Mhamdi M, Aleya L, Janati-Idrissi A. Isolation and characterization of a mesophilic cellulolytic endophyte Preussia africana from Juniperus oxycedrus. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:45589-45600. [PMID: 35146609 DOI: 10.1007/s11356-022-19151-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 02/06/2022] [Indexed: 06/14/2023]
Abstract
The medicinal plant Juniperus oxycedrus is less recognized for the diversity of its fungal endophytes and their potential to produce extracellular enzymes. The present study is the first report on the isolation and identification of a mesophilic endophytic strain JO-A, Preussia africana, from fresh stems of the J. oxycedrus endemic tree in the Ifrane region-Morocco, and the evaluation of its ability to produce cellulases. A one-time multi-parameter one-factor screening was optimized to select factors that enhance cellulase production in P. africana. The maximum production of both CMCase and FPase activities were 1.913 IU.mL-1 and 0.885 IU.mL-1, respectively, when the medium was supplemented with 2% w/v glucose. These remarkable titers were tenfold greater than those obtained under the initial non-optimized conditions. This mesophilic P. africana JO-A strain grows and actively produces cellulases at 37 °C demonstrating its great potential for various biotechnology applications. The cellulolytic extract showed the highest enzymatic activities at pH 5.0 and 50 °C with a half-life of 24 h at 50 °C.
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Affiliation(s)
- Loubna Seddouk
- Laboratory of Biotechnology, Conservation and Valorization of Natural Resources, Faculty of Sciences DM, Sidi Mohammed Ben Abdellah University, P.O. Box 1796 Atlas, Fez, Morocco
| | - Latifa Jamai
- Laboratory of Biotechnology, Conservation and Valorization of Natural Resources, Faculty of Sciences DM, Sidi Mohammed Ben Abdellah University, P.O. Box 1796 Atlas, Fez, Morocco
| | - Karima Tazi
- Laboratory of Biotechnology, Conservation and Valorization of Natural Resources, Faculty of Sciences DM, Sidi Mohammed Ben Abdellah University, P.O. Box 1796 Atlas, Fez, Morocco
| | - Mohamed Ettayebi
- The Institute for Infectious Disease Research, McMaster University, 1280 Main Street West, Hamilton, ON, Canada
| | - Mohammed Alaoui-Mhamdi
- Laboratory of Biotechnology, Conservation and Valorization of Natural Resources, Faculty of Sciences DM, Sidi Mohammed Ben Abdellah University, P.O. Box 1796 Atlas, Fez, Morocco.
| | - Lotfi Aleya
- CNRS 6249-Université de Franche-Comté, 16, route de Gray F-25030, Besançon cedex, France
| | - Abellatif Janati-Idrissi
- Laboratory of Biotechnology, Conservation and Valorization of Natural Resources, Faculty of Sciences DM, Sidi Mohammed Ben Abdellah University, P.O. Box 1796 Atlas, Fez, Morocco
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Thermostable cellulose saccharifying microbial enzymes: Characteristics, recent advances and biotechnological applications. Int J Biol Macromol 2021; 188:226-244. [PMID: 34371052 DOI: 10.1016/j.ijbiomac.2021.08.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/19/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022]
Abstract
Cellulases play a promising role in the bioconversion of renewable lignocellulosic biomass into fermentable sugars which are subsequently fermented to biofuels and other value-added chemicals. Besides biofuel industries, they are also in huge demand in textile, detergent, and paper and pulp industries. Low titres of cellulase production and processing are the main issues that contribute to high enzyme cost. The success of ethanol-based biorefinery depends on high production titres and the catalytic efficiency of cellulases functional at elevated temperatures with acid/alkali tolerance and the low cost. In view of their wider application in various industrial processes, stable cellulases that are active at elevated temperatures in the acidic-alkaline pH ranges, and organic solvents and salt tolerance would be useful. This review provides a recent update on the advances made in thermostable cellulases. Developments in their sources, characteristics and mechanisms are updated. Various methods such as rational design, directed evolution, synthetic & system biology and immobilization techniques adopted in evolving cellulases with ameliorated thermostability and characteristics are also discussed. The wide range of applications of thermostable cellulases in various industrial sectors is described.
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Kuntothom T, Cairns JK. Expression and characterization of TbCel12A, a thermophilic endoglucanase with potential in biomass hydrolysis. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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7
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Akram F, Haq IU. Overexpression and characterization of TnCel12B, a hyperthermophilic GH12 endo-1,4-β-glucanase cloned from Thermotoga naphthophila RKU-10 T. Anal Biochem 2020; 599:113741. [PMID: 32339490 DOI: 10.1016/j.ab.2020.113741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/08/2020] [Accepted: 04/14/2020] [Indexed: 11/26/2022]
Abstract
A putative cellulolytic gene (825 bp) from Thermotoga naphthophila RKU-10T was overexpressed as an active soluble endo-1,4-β-glucanase (TnCel12B), belongs to glycoside hydrolase family 12 (GH12), in a mesophilic expression host. Heterologous expression and engineered bacterial cell mass was improved through specific strategies (induction and cultivation). Hence, intracellular activity of TnCel12B was enhanced in ZYBM9 modified medium (pH 7.0) by 8.38 and 6.25 fold with lactose (200 mM) and IPTG (0.5 mM) induction, respectively; and 6.95 fold was increased in ZYP-5052 auto-inducing medium after 8 h incubation at 26 °C (200 rev min-1). Purified TnCel12B with a molecular weight of ~32 kDa, was optimally active at 90 °C and pH 6.0; and exhibited prodigious stability over a wide range of temperature (50-85 °C) and pH (5.0-9.0) for 8 h TnCel12B displayed great resistance towards different chemical modulators, though activity was improved by Mg2+, Zn2+, Pb2+ and Ca2+. Purified TnCel12B had affinity with various substrates but peak activity was observed toward barley β-glucan (1664 U mg-1) and carboxymethyl cellulose (736 U mg-1). The values of Km, Vmax, kcat, and kcatKm-1 were found to be 4.63 mg mL-1, 916 μmol mg-1min-1, 1326.7 s-1 and 286.54 mL mg-1 s-1, respectively using CMC substrate. All noteworthy features of TnCel12B make it an appropriate industrial candidate for bioethanol production and various other potential applications.
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Affiliation(s)
- Fatima Akram
- Institute of Industrial Biotechnology, GC University, Lahore, 54000, Pakistan.
| | - Ikram Ul Haq
- Institute of Industrial Biotechnology, GC University, Lahore, 54000, Pakistan.
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Wang S, Lin R, Ren Y, Zhang T, Lu H, Wang L, Fan D. Non-chromatographic purification of thermostable endoglucanase from Thermotoga maritima by fusion with a hydrophobic elastin-like polypeptide. Protein Expr Purif 2020; 173:105634. [PMID: 32325232 DOI: 10.1016/j.pep.2020.105634] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/26/2020] [Accepted: 03/31/2020] [Indexed: 01/08/2023]
Abstract
Endoglucanase EG12B from Thermotoga maritima is a thermophilic cellulase that has great potential for industrial applications. Here, to enable the selective purification of EG12B in a simple and efficient manner, an elastin-like polypeptide (ELP), which acts as a thermally responsive polypeptide, was fused with EG12B to enable its inverse phase transition cycling (ITC). A small gene library comprising ELPs from ELP5 to ELP50 was constructed using recursive directional ligation by plasmid reconstruction. ELP50 was added to the C-terminus of EG12B as a fusion tag to obtain the expression vector pET28-EG12B-ELP50, which was transformed into Escherichia coli BL21 (DE3) to enable the expression of fusion protein via IPTG induction. Gray scanning analysis revealed that the EG12B-ELP50 expression level was up to about 35% of the total cellular proteins. After three rounds of ITC, 8.14 mg of EG12B-ELP50 was obtained from 500-mL lysogeny broth culture medium. The recovery rate and purification fold of EG12B-ELP50 purified by ITC reached 78.1% and 11.8, respectively. The cellulase activity assay showed that EG12B-ELP50 had a better thermostability, higher optimal temperature, and longer half-life than those of free EG12B. Overall, our results suggested that ELP50 could be used as a favorable fusion tag, providing a rapid, simple, and inexpensive strategy for non-chromatographic target-protein purification.
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Affiliation(s)
- Shanshan Wang
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, 723001, China; Shaanxi Key Laboratory of Degradable Biomedical Materials, School of Chemical Engineering, Northwest University, Taibai North Road 229, Xi'an, 710069, China.
| | - Rui Lin
- Department of Gastroenterology and Hepatology, Tianjin Medical University, General Hospital, Tianjin, 300052, China
| | - Yanyan Ren
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, 723001, China
| | - Tao Zhang
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, 723001, China
| | - Hongzhao Lu
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, 723001, China
| | - Ling Wang
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, 723001, China
| | - Daidi Fan
- Shaanxi Key Laboratory of Degradable Biomedical Materials, School of Chemical Engineering, Northwest University, Taibai North Road 229, Xi'an, 710069, China.
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Zhu Z, Qu J, Yu L, Jiang X, Liu G, Wang L, Qu Y, Qin Y. Three glycoside hydrolase family 12 enzymes display diversity in substrate specificities and synergistic action between each other. Mol Biol Rep 2019; 46:5443-5454. [PMID: 31359382 DOI: 10.1007/s11033-019-04999-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/23/2019] [Indexed: 12/01/2022]
Abstract
PoCel12A, PoCel12B, and PoCel12C are genes that encode glycoside hydrolase family 12 (GH12) enzymes in Penicillium oxalicum. PoCel12A and PoCel12B are typical GH12 enzymes that belong to fungal subfamilies 12-1 and 12-2, respectively. PoCel12C contains a low-complexity region (LCR) domain, which is not found in PoCel12A or PoCel12B and independent of fungal subfamily 12-1 or 12-2. Recombinant enzymes (named rCel12A, rCel12B and rCel12C) demonstrate existing diversity in the substrate specificities. Although most members in GH family 12 are typical endoglucanases and preferentially hydrolyze β-1,4-glucan (e.g., carboxymethylcellulose), recombinant PoCel12A is a non-typical endo-(1-4)-β-glucanase; it preferentially hydrolyzes mix-linked β-glucan (barley β-glucan, β-1,3-1,4-glucan) and slightly hydrolyzes β-1,4-glucan (carboxymethylcellulose). Recombinant PoCel12B possesses a significantly high activity against xyloglucan. A specific activity of rCel12B toward xyloglucan (239 µmol/min/mg) is the second-highest value known. Recombinant PoCel12C shows low activity toward β-glucan, carboxymethylcellulose, or xyloglucan. All three enzymes can degrade phosphoric acid-swollen cellulose (PASC). However, the hydrolysis products toward PASC by enzymes are different: the main hydrolysis products are cellotriose, cellotetraose, and cellobiose for rCel12A, rCel12B, and rCel12C, correspondingly. A synergistic action toward PASC among rCel12A and rCel12B is observed, thereby suggesting a potential application for preparing enzyme cocktails used in lignocellulose hydrolysis.
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Affiliation(s)
- Zhu Zhu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Jingyao Qu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Lele Yu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Xukai Jiang
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,Department of Microbiology, Faculty of Medicine, Nursing and Health Sciences, Monash Biomedicine Discovery Institute, Monash University, Melbourne, 3800, Australia
| | - Guodong Liu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Lushan Wang
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Yinbo Qu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China. .,State Key Lab of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.
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Wang Y, Leng L, Islam MK, Liu F, Lin CSK, Leu SY. Substrate-Related Factors Affecting Cellulosome-Induced Hydrolysis for Lignocellulose Valorization. Int J Mol Sci 2019; 20:ijms20133354. [PMID: 31288425 PMCID: PMC6651384 DOI: 10.3390/ijms20133354] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/30/2019] [Accepted: 07/03/2019] [Indexed: 11/22/2022] Open
Abstract
Cellulosomes are an extracellular supramolecular multienzyme complex that can efficiently degrade cellulose and hemicelluloses in plant cell walls. The structural and unique subunit arrangement of cellulosomes can promote its adhesion to the insoluble substrates, thus providing individual microbial cells with a direct competence in the utilization of cellulosic biomass. Significant progress has been achieved in revealing the structures and functions of cellulosomes, but a knowledge gap still exists in understanding the interaction between cellulosome and lignocellulosic substrate for those derived from biorefinery pretreatment of agricultural crops. The cellulosomic saccharification of lignocellulose is affected by various substrate-related physical and chemical factors, including native (untreated) wood lignin content, the extent of lignin and xylan removal by pretreatment, lignin structure, substrate size, and of course substrate pore surface area or substrate accessibility to cellulose. Herein, we summarize the cellulosome structure, substrate-related factors, and regulatory mechanisms in the host cells. We discuss the latest advances in specific strategies of cellulosome-induced hydrolysis, which can function in the reaction kinetics and the overall progress of biorefineries based on lignocellulosic feedstocks.
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Affiliation(s)
- Ying Wang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-Environmental Science & Technology, Guangzhou 510650, China
- Department of Civil and Environmental Engineering, the Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Ling Leng
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
| | - Md Khairul Islam
- Department of Civil and Environmental Engineering, the Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Fanghua Liu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-Environmental Science & Technology, Guangzhou 510650, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Shao-Yuan Leu
- Department of Civil and Environmental Engineering, the Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
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Asymmetric synthesis of l-phosphinothricin using thermostable alpha-transaminase mined from Citrobacter koseri. J Biotechnol 2019; 302:10-17. [PMID: 31201835 DOI: 10.1016/j.jbiotec.2019.06.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/30/2019] [Accepted: 06/11/2019] [Indexed: 11/22/2022]
Abstract
α-Transaminase (α-TA) responsible for catalyzing the reversible transfer of amino groups between amine donors and amine acceptors, is applicable to enzymatic route for asymmetric synthesis of herbicide l-phosphinothricin (l-PPT). In the search for α-TAs with better catalysis performance, three α-TAs were discovered by genome mining approach using a known sequence encoding Escherichia coli tyrosine TA (TyrB) as probe. Through detailed comparison of their expression amount, activities and characteristics, Citrobacter koseri TA (CkTA) exhibited better activity and thermostability, which retain 65.9% of initial activity after incubation at 57 °C for 4 h. The Km and kcat/Km values of CkTA were 36.75 mM and 34.29 mM-1 min-1, respectively. In addition, recombinant CkTA cells were immobilized onto Celite 545 using tris(hydroxymethyl)phosphine as crosslinker. During five repetitive asymmetric synthesis of l-PPT from 20 g/L prostereogenic ketone using l-Glu as amine donor, all the yields of l-PPT reached up to 91.2% (>99% ee). These characteristics made CkTA a valuable addition to the currently scarce α-TA library for stereospecific synthesis of l-PPT.
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A Thermostable Aspergillus fumigatus GH7 Endoglucanase Over-Expressed in Pichia pastoris Stimulates Lignocellulosic Biomass Hydrolysis. Int J Mol Sci 2019; 20:ijms20092261. [PMID: 31067833 PMCID: PMC6540056 DOI: 10.3390/ijms20092261] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 04/30/2019] [Accepted: 05/05/2019] [Indexed: 12/15/2022] Open
Abstract
In the context of avoiding the use of non-renewable energy sources, employing lignocellulosic biomass for ethanol production remains a challenge. Cellulases play an important role in this scenario: they are some of the most important industrial enzymes that can hydrolyze lignocellulose. This study aims to improve on the characterization of a thermostable Aspergillus fumigatus endo-1,4-β-glucanase GH7 (Af-EGL7). To this end, Af-EGL7 was successfully expressed in Pichia pastoris X-33. The kinetic parameters Km and Vmax were estimated and suggested a robust enzyme. The recombinant protein was highly stable within an extreme pH range (3.0-8.0) and was highly thermostable at 55 °C for 72 h. Low Cu2+ concentrations (0.1-1.0 mM) stimulated Af-EGL7 activity up to 117%. Af-EGL7 was tolerant to inhibition by products, such as glucose and cellobiose. Glucose at 50 mM did not inhibit Af-EGL7 activity, whereas 50 mM cellobiose inhibited Af-EGL7 activity by just 35%. Additionally, the Celluclast® 1.5L cocktail supplemented with Af-EGL7 provided improved hydrolysis of sugarcane bagasse "in natura", sugarcane exploded bagasse (SEB), corncob, rice straw, and bean straw. In conclusion, the novel characterization of Af-EGL7 conducted in this study highlights the extraordinary properties that make Af-EGL7 a promising candidate for industrial applications.
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Expression and characterisation of a thermophilic endo-1,4-β-glucanase from Sulfolobus shibatae of potential industrial application. Mol Biol Rep 2018; 45:2201-2211. [DOI: 10.1007/s11033-018-4381-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 09/12/2018] [Indexed: 12/17/2022]
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14
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Escuder-Rodríguez JJ, DeCastro ME, Cerdán ME, Rodríguez-Belmonte E, Becerra M, González-Siso MI. Cellulases from Thermophiles Found by Metagenomics. Microorganisms 2018; 6:microorganisms6030066. [PMID: 29996513 PMCID: PMC6165527 DOI: 10.3390/microorganisms6030066] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/04/2018] [Accepted: 07/05/2018] [Indexed: 01/05/2023] Open
Abstract
Cellulases are a heterogeneous group of enzymes that synergistically catalyze the hydrolysis of cellulose, the major component of plant biomass. Such reaction has biotechnological applications in a broad spectrum of industries, where they can provide a more sustainable model of production. As a prerequisite for their implementation, these enzymes need to be able to operate in the conditions the industrial process requires. Thus, cellulases retrieved from extremophiles, and more specifically those of thermophiles, are likely to be more appropriate for industrial needs in which high temperatures are involved. Metagenomics, the study of genes and gene products from the whole community genomic DNA present in an environmental sample, is a powerful tool for bioprospecting in search of novel enzymes. In this review, we describe the cellulolytic systems, we summarize their biotechnological applications, and we discuss the strategies adopted in the field of metagenomics for the discovery of new cellulases, focusing on those of thermophilic microorganisms.
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Affiliation(s)
- Juan-José Escuder-Rodríguez
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Eugenia DeCastro
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Esperanza Cerdán
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - Esther Rodríguez-Belmonte
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - Manuel Becerra
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Isabel González-Siso
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
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15
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The unique GH5 cellulase member in the extreme halotolerant fungus Aspergillus glaucus CCHA is an endoglucanase with multiple tolerance to salt, alkali and heat: prospects for straw degradation applications. Extremophiles 2018; 22:675-685. [DOI: 10.1007/s00792-018-1028-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 04/13/2018] [Indexed: 12/14/2022]
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16
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The PT/S-Box of Modular Cellulase AcCel12B Plays a Key Role in the Hydrolysis of Insoluble Cellulose. Catalysts 2018. [DOI: 10.3390/catal8030123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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17
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Characterization of a Thermophilic Monosaccharide Stimulated β-Glucosidase from Acidothermus cellulolyticus. Chem Res Chin Univ 2018. [DOI: 10.1007/s40242-018-7408-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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18
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Rungrattanakasin B, Premjet S, Thanonkeo S, Klanrit P, Thanonkeo P. Cloning and expression of an endoglucanase gene from the thermotolerant fungus Aspergillus fumigatus DBiNU-1 in Kluyveromyces lactis. Braz J Microbiol 2018; 49:647-655. [PMID: 29449177 PMCID: PMC6066738 DOI: 10.1016/j.bjm.2017.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 09/30/2017] [Accepted: 10/14/2017] [Indexed: 11/24/2022] Open
Abstract
An intronless endoglucanase from thermotolerant Aspergillus fumigatus DBINU-1 was cloned, characterized and expressed in the yeast Kluyveromyces lactis. The full-length open reading frame of the endoglucanase gene from A. fumigatus DBiNU-1, designated Cel7, was 1383 nucleotides in length and encoded a protein of 460 amino acid residues. The predicted molecular weight and the isoelectric point of the A. fumigatus Cel7 gene product were 48.19 kDa and 5.03, respectively. A catalytic domain in the N-terminal region and a fungal type cellulose-binding domain/module in the C-terminal region were detected in the predicted polypeptide sequences. Furthermore, a signal peptide with 20 amino acid residues at the N-terminus was also detected in the deduced amino acid sequences of the endoglucanase from A. fumigatus DBiNU-1. The endoglucanase from A. fumigatus DBiNU-1 was successfully expressed in K. lactis, and the purified recombinant enzyme exhibited its maximum activity at pH 5.0 and 60 °C. The enzyme was very stable in a pH range from 4.0 to 8.0 and a temperature range from 30 to 60 °C. These features make it suitable for application in the paper, biofuel, and other chemical production industries that use cellulosic materials.
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Affiliation(s)
| | - Siripong Premjet
- Naresuan University, Faculty of Science, Department of Biology, Phitsanulok, Thailand
| | - Sudarat Thanonkeo
- Mahasarakham University, Walai Rukhavej Botanical Research Institute, Maha Sarakham, Thailand
| | - Preekamol Klanrit
- Khon Kaen University, Faculty of Technology, Department of Biotechnology, Khon Kaen, Thailand; Khon Kaen University, Faculty of Technology, Fermentation Research Center for Value Added Agricultural Products, Khon Kaen, Thailand
| | - Pornthap Thanonkeo
- Khon Kaen University, Faculty of Technology, Department of Biotechnology, Khon Kaen, Thailand; Khon Kaen University, Faculty of Technology, Fermentation Research Center for Value Added Agricultural Products, Khon Kaen, Thailand.
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Ma H, Delafield DG, Wang Z, You J, Wu S. Finding Biomass Degrading Enzymes Through an Activity-Correlated Quantitative Proteomics Platform (ACPP). JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:655-663. [PMID: 28083757 PMCID: PMC5373979 DOI: 10.1007/s13361-016-1569-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/29/2016] [Accepted: 11/21/2016] [Indexed: 06/06/2023]
Abstract
The microbial secretome, known as a pool of biomass (i.e., plant-based materials) degrading enzymes, can be utilized to discover industrial enzyme candidates for biofuel production. Proteomics approaches have been applied to discover novel enzyme candidates through comparing protein expression profiles with enzyme activity of the whole secretome under different growth conditions. However, the activity measurement of each enzyme candidate is needed for confident "active" enzyme assignments, which remains to be elucidated. To address this challenge, we have developed an Activity-Correlated Quantitative Proteomics Platform (ACPP) that systematically correlates protein-level enzymatic activity patterns and protein elution profiles using a label-free quantitative proteomics approach. The ACPP optimized a high performance anion exchange separation for efficiently fractionating complex protein samples while preserving enzymatic activities. The detected enzymatic activity patterns in sequential fractions using microplate-based assays were cross-correlated with protein elution profiles using a customized pattern-matching algorithm with a correlation R-score. The ACPP has been successfully applied to the identification of two types of "active" biomass-degrading enzymes (i.e., starch hydrolysis enzymes and cellulose hydrolysis enzymes) from Aspergillus niger secretome in a multiplexed fashion. By determining protein elution profiles of 156 proteins in A. niger secretome, we confidently identified the 1,4-α-glucosidase as the major "active" starch hydrolysis enzyme (R = 0.96) and the endoglucanase as the major "active" cellulose hydrolysis enzyme (R = 0.97). The results demonstrated that the ACPP facilitated the discovery of bioactive enzymes from complex protein samples in a high-throughput, multiplexing, and untargeted fashion. Graphical Abstract ᅟ.
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Affiliation(s)
- Hongyan Ma
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Daniel G Delafield
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Jianlan You
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.
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Jiang X, Zhou X, Liu Q, Zheng L, Yu N, Li W. Expression of Acidothermus cellulolyticus thermostable cellulases in tobacco and rice plants. BIOTECHNOL BIOTEC EQ 2016. [DOI: 10.1080/13102818.2016.1236671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Xiran Jiang
- Department of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, PR China
| | - Xiaoya Zhou
- Molecular Medicine and Chemistry Laboratory Foundation College, Jining Medical University, Jining, PR China
| | - Qi Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai, PR China
| | - Lulu Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai, PR China
| | - Ning Yu
- The First Clinical College, Liaoning University of Traditional Chinese Medicine, Shenyang, PR China
| | - Wenli Li
- School of Life Science and Medicine, Dalian University of Technology, Panjin, PR China
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Comparative Community Proteomics Demonstrates the Unexpected Importance of Actinobacterial Glycoside Hydrolase Family 12 Protein for Crystalline Cellulose Hydrolysis. mBio 2016; 7:mBio.01106-16. [PMID: 27555310 PMCID: PMC4999548 DOI: 10.1128/mbio.01106-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacterium Thermobispora bispora that were highly abundant in the most active consortium. Among the cellulases from T. bispora, the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite of T. bispora hydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered. Cellulose is the most abundant organic polymer on earth, and its enzymatic hydrolysis is a key reaction in the global carbon cycle and the conversion of plant biomass to biofuels. The glycoside hydrolases that depolymerize crystalline cellulose have been primarily characterized from isolates. In this study, we demonstrate that adapting microbial consortia from compost to grow on crystalline cellulose generated communities whose soluble enzymes exhibit differential abilities to hydrolyze crystalline cellulose. Comparative proteomics of these communities identified a protein of glycoside hydrolase family 12 (GH12), a family of proteins previously observed to primarily hydrolyze soluble substrates, as a candidate that accounted for some of the differences in hydrolytic activities. Heterologous expression confirmed that the GH12 protein identified by proteomics was active on crystalline cellulose and hydrolyzed cellulose by a random mechanism, in contrast to most cellulases that act on the crystalline polymer in a processive mechanism.
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