1
|
Gonçalves ACDS, Rezende RP, Marques EDLS, Soares MR, Dias JCT, Romano CC, Costa MS, Dotivo NC, de Moura SR, de Oliveira IS, Pirovani CP. Biotechnological potential of mangrove sediments: Identification and functional attributes of thermostable and salinity-tolerant β-glucanase. Int J Biol Macromol 2020; 147:521-526. [DOI: 10.1016/j.ijbiomac.2020.01.078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/14/2019] [Accepted: 01/07/2020] [Indexed: 11/25/2022]
|
2
|
Bychkov A, Podgorbunskikh E, Bychkova E, Lomovsky O. Current achievements in the mechanically pretreated conversion of plant biomass. Biotechnol Bioeng 2019; 116:1231-1244. [DOI: 10.1002/bit.26925] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 11/13/2018] [Accepted: 01/17/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Aleksey Bychkov
- Laboratory of Solid State ChemistryInstitute of Solid State Chemistry and Mechanochemistry Russian Academy of Sciences Novosibirsk Russia
- Department of Technology of Food Production, Novosibirsk State Technical UniversityNovosibirsk Russia
| | - Ekaterina Podgorbunskikh
- Laboratory of Solid State ChemistryInstitute of Solid State Chemistry and Mechanochemistry Russian Academy of Sciences Novosibirsk Russia
| | - Elena Bychkova
- Department of Technology of Food Production, Novosibirsk State Technical UniversityNovosibirsk Russia
| | - Oleg Lomovsky
- Laboratory of Solid State ChemistryInstitute of Solid State Chemistry and Mechanochemistry Russian Academy of Sciences Novosibirsk Russia
| |
Collapse
|
3
|
The characterization of the endoglucanase Cel12A from Gloeophyllum trabeum reveals an enzyme highly active on β-glucan. PLoS One 2014; 9:e108393. [PMID: 25251390 PMCID: PMC4177221 DOI: 10.1371/journal.pone.0108393] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 08/21/2014] [Indexed: 11/19/2022] Open
Abstract
The basidiomycete fungus Gloeophyllum trabeum causes a typical brown rot and is known to use reactive oxygen species in the degradation of cellulose. The extracellular Cel12A is one of the few endo-1,4-β-glucanase produced by G. trabeum. Here we cloned cel12A and heterologously expressed it in Aspergillus niger. The identity of the resulting recombinant protein was confirmed by mass spectrometry. We used the purified GtCel12A to determine its substrate specificity and basic biochemical properties. The G. trabeum Cel12A showed highest activity on β-glucan, followed by lichenan, carboxymethylcellulose, phosphoric acid swollen cellulose, microcrystalline cellulose, and filter paper. The optimal pH and temperature for enzymatic activity were, respectively, 4.5 and 50°C on β-glucan. Under these conditions specific activity was 239.2±9.1 U mg−1 and the half-life of the enzyme was 84.6±3.5 hours. Thermofluor studies revealed that the enzyme was most thermal stable at pH 3. Using β-glucan as a substrate, the Km was 3.2±0.5 mg mL−1 and the Vmax was 0.41±0.02 µmol min−1. Analysis of the effects of GtCel12A on oat spelt and filter paper by scanning electron microscopy revealed the morphological changes taking place during the process.
Collapse
|
4
|
Arantes V, Gourlay K, Saddler JN. The enzymatic hydrolysis of pretreated pulp fibers predominantly involves "peeling/erosion" modes of action. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:87. [PMID: 24976863 PMCID: PMC4062648 DOI: 10.1186/1754-6834-7-87] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 05/23/2014] [Indexed: 05/07/2023]
Abstract
BACKGROUND There is still considerable debate regarding the actual mechanism by which a "cellulase mixture" deconstructs cellulosic materials, with accessibility to the substrate at the microscopic level being one of the major restrictions that limits fast, complete cellulose hydrolysis. In the work reported here we tried to determine the predominant mode of action, at the fiber level, of how a cellulase mixture deconstructs pretreated softwood and hardwood pulp fibers. Quantitative changes in the pulp fibers derived from different pretreated biomass substrates were monitored throughout the course of enzymatic hydrolysis to see if the dominant mechanisms involved either the fragmentation/cutting of longer fibers to shorter fibers or their "peeling/delamination/erosion," or if both cutting and peeling mechanisms occurred simultaneously. RESULTS Regardless of the source of biomass, the type of pretreatment and the chemical composition of the substrate, under typical hydrolysis conditions (50°C, pH 4.8, mixing) longer pulp fibers (fiber length >200 μm) were rapidly broken down until a relatively constant fiber length of 130 to 160 μm was reached. In contrast, shorter fibers with an initial average fiber length of 130 to 160 μm showed no significant change in length despite their substantial hydrolysis. The fragmentation/cutting mode of deconstruction was only observed on longer fibers at early stages of hydrolysis. Although the fiber fragmentation mode of deconstruction was not greatly influenced by enzyme loading, it was significantly inhibited by glucose and was mainly observed during initial mixing of the enzyme and substrate. In contrast, significant changes in the fiber width occurred throughout the course of hydrolysis for all of the substrates, suggesting that fiber width may limit the rate and extent of cellulose hydrolysis. CONCLUSION It appears that, at the fiber level, pretreated pulp fibers are hydrolyzed through a two-step mode of action involving an initial rapid fragmentation followed by simultaneous swelling and peeling/erosion of the fragmented fibers. This latter mechanism is the predominant mode of action involved in effectively hydrolyzing the cellulose present in pretreated wood substrates.
Collapse
Affiliation(s)
- Valdeir Arantes
- University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Keith Gourlay
- University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Jack N Saddler
- University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| |
Collapse
|
5
|
Barakat A, de Vries H, Rouau X. Dry fractionation process as an important step in current and future lignocellulose biorefineries: a review. BIORESOURCE TECHNOLOGY 2013; 134:362-73. [PMID: 23499177 DOI: 10.1016/j.biortech.2013.01.169] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 01/28/2013] [Accepted: 01/30/2013] [Indexed: 05/02/2023]
Abstract
The use of lignocellulosic biomass is promising for biofuels and materials and new technologies for the conversion need to be developed. However, the inherent properties of native lignocellulosic materials make them resistant to enzymatic and chemical degradation. Lignocellulosic biomass requires being pretreated to change the physical and chemical properties of lignocellulosic matrix in order to increase cell wall polymers accessibility and bioavailability. Mechanical size reduction may be chemical free intensive operation thanks to decreasing particles size and cellulose crystallinity, and increasing accessible surface area. Changes in these parameters improve the digestibility and the bioconversion of lignocellulosic biomass. However, mechanical size reduction requires cost-effective approaches from an energy input point of view. Therefore, the energy consumption in relation to physicochemical properties of lignocellulosic biomass was discussed. Even more, chemical treatments combined with physicochemical size reduction approaches are proposed to reduce energy consumption in this review.
Collapse
Affiliation(s)
- Abdellatif Barakat
- INRA, UMR 1208 Ingénierie des Agropolymères et Technologies Emergentes 2, Place Pierre Viala, 34060 Montpellier Cedex 1, France.
| | | | | |
Collapse
|
6
|
Silveira MHL, Rau M, Andreaus J. Influence of mechanical agitation on the pH profile of total, soluble and insoluble filter paper activity of Hypocrea jecorina cellulase preparations. BIOCATAL BIOTRANSFOR 2012. [DOI: 10.3109/10242422.2012.645368] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
7
|
Levine SE, Fox JM, Clark DS, Blanch HW. A mechanistic model for rational design of optimal cellulase mixtures. Biotechnol Bioeng 2011; 108:2561-70. [DOI: 10.1002/bit.23249] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 06/06/2011] [Accepted: 06/20/2011] [Indexed: 11/07/2022]
|
8
|
Lindorfer J, Steinmüller H, Auer W, Jäger A, Eder A. Untersuchung der Vorhydrolyse von Lignocelluloserohstoffen mittels Steam Explosion. CHEM-ING-TECH 2010. [DOI: 10.1002/cite.201000057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
9
|
Lindorfer J, Steinmüller H, Auer W, Nidetzky B, Loncar E, Jäger A, Eder A, Hofer B. Untersuchungen zur Herstellung von Bioethanol und Biogas aus Lignocelluloserohstoffen nach Vorbehandlung mit Steam Explosion und Cellulasen. CHEM-ING-TECH 2010. [DOI: 10.1002/cite.201000049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
10
|
Park S, Baker JO, Himmel ME, Parilla PA, Johnson DK. Cellulose crystallinity index: measurement techniques and their impact on interpreting cellulase performance. BIOTECHNOLOGY FOR BIOFUELS 2010; 3:10. [PMID: 20497524 PMCID: PMC2890632 DOI: 10.1186/1754-6834-3-10] [Citation(s) in RCA: 1141] [Impact Index Per Article: 81.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 05/24/2010] [Indexed: 05/02/2023]
Abstract
Although measurements of crystallinity index (CI) have a long history, it has been found that CI varies significantly depending on the choice of measurement method. In this study, four different techniques incorporating X-ray diffraction and solid-state 13C nuclear magnetic resonance (NMR) were compared using eight different cellulose preparations. We found that the simplest method, which is also the most widely used, and which involves measurement of just two heights in the X-ray diffractogram, produced significantly higher crystallinity values than did the other methods. Data in the literature for the cellulose preparation used (Avicel PH-101) support this observation. We believe that the alternative X-ray diffraction (XRD) and NMR methods presented here, which consider the contributions from amorphous and crystalline cellulose to the entire XRD and NMR spectra, provide a more accurate measure of the crystallinity of cellulose. Although celluloses having a high amorphous content are usually more easily digested by enzymes, it is unclear, based on studies published in the literature, whether CI actually provides a clear indication of the digestibility of a cellulose sample. Cellulose accessibility should be affected by crystallinity, but is also likely to be affected by several other parameters, such as lignin/hemicellulose contents and distribution, porosity, and particle size. Given the methodological dependency of cellulose CI values and the complex nature of cellulase interactions with amorphous and crystalline celluloses, we caution against trying to correlate relatively small changes in CI with changes in cellulose digestibility. In addition, the prediction of cellulase performance based on low levels of cellulose conversion may not include sufficient digestion of the crystalline component to be meaningful.
Collapse
Affiliation(s)
- Sunkyu Park
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - John O Baker
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - Philip A Parilla
- National Center for Photovoltaics, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - David K Johnson
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| |
Collapse
|
11
|
Penttilä PA, Várnai A, Leppänen K, Peura M, Kallonen A, Jääskeläinen P, Lucenius J, Ruokolainen J, Siika-aho M, Viikari L, Serimaa R. Changes in Submicrometer Structure of Enzymatically Hydrolyzed Microcrystalline Cellulose. Biomacromolecules 2010; 11:1111-7. [DOI: 10.1021/bm1001119] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Paavo A. Penttilä
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Anikó Várnai
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Kirsi Leppänen
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Marko Peura
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Aki Kallonen
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Pentti Jääskeläinen
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Jessica Lucenius
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Janne Ruokolainen
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Matti Siika-aho
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Liisa Viikari
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| | - Ritva Serimaa
- Departments of Physics and Food and Environmental Sciences, University of Helsinki, Helsinki, Finland, Departments of Biomedical Engineering and Computational Science and Applied Physics, Aalto University School of Science and Technology, Espoo, Finland, and VTT Technical Research Centre of Finland, Espoo, Finland
| |
Collapse
|
12
|
Lynd LR, Weimer PJ, van Zyl WH, Pretorius IS. Microbial cellulose utilization: fundamentals and biotechnology. Microbiol Mol Biol Rev 2002; 66:506-77, table of contents. [PMID: 12209002 PMCID: PMC120791 DOI: 10.1128/mmbr.66.3.506-577.2002] [Citation(s) in RCA: 2307] [Impact Index Per Article: 104.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial cellulose utilization, kinetics of microbial cellulose utilization, and contrasting features compared to soluble substrate kinetics. A biological perspective on processing cellulosic biomass is presented, including features of pretreated substrates and alternative process configurations. Organism development is considered for "consolidated bioprocessing" (CBP), in which the production of cellulolytic enzymes, hydrolysis of biomass, and fermentation of resulting sugars to desired products occur in one step. Two organism development strategies for CBP are examined: (i) improve product yield and tolerance in microorganisms able to utilize cellulose, or (ii) express a heterologous system for cellulose hydrolysis and utilization in microorganisms that exhibit high product yield and tolerance. A concluding discussion identifies unresolved issues pertaining to microbial cellulose utilization, suggests approaches by which such issues might be resolved, and contrasts a microbially oriented cellulose hydrolysis paradigm to the more conventional enzymatically oriented paradigm in both fundamental and applied contexts.
Collapse
Affiliation(s)
- Lee R Lynd
- Chemical and Biochemical Engineering, Thayer School of Engineering and Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA.
| | | | | | | |
Collapse
|