1
|
Chen Z, Wang L, Shen Y, Hu D, Zhou L, Lu F, Li M. Improving Thermostability of Chimeric Enzymes Generated by Domain Shuffling Between Two Different Original Glucoamylases. Front Bioeng Biotechnol 2022; 10:881421. [PMID: 35449593 PMCID: PMC9017332 DOI: 10.3389/fbioe.2022.881421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/08/2022] [Indexed: 11/13/2022] Open
Abstract
In order to improve enzymatic properties of glucoamylases, six recombinant genes GA1–GA6 were created by domain shuffling of glucoamylase genes GAA1 from Aspergillus niger Ld418AI and GATE from Talaromyces emersonii Ld418 TE using overlap extension PCR and were expressed in Saccharomyces cerevisiae W303-1B; only activities of GA1 and GA2 in the fermentation broth were higher than those of GAA1 but less than those of GATE. Further research results of GA1 and GA2 indicated that chimeric glucoamylases GA1 and GA2 revealed increased thermostability compared with GAA1 and GATE, although with a slight change in the activity and optimal temperature. However, GA1 had almost the same catalytic efficiency as GATE, whereas the catalytic efficiency of GA2 was slightly less than that of GATE, but still higher than that of GAA1. The structural analysis showed that the change of enzymatic properties could be caused by the increased and extended α-helix and β-sheet, which change the secondary and tertiary structures of chimeric glucoamylases. These results demonstrated that domain shuffling was feasible to generate a chimeric enzyme with novel properties.
Collapse
Affiliation(s)
- Zhongxiu Chen
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Longbin Wang
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yuyu Shen
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Dunji Hu
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Liying Zhou
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
- Tianjin Key Laboratory of Industrial Microbiology, Tianjin, China
- *Correspondence: Fuping Lu, ; Ming Li,
| | - Ming Li
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
- Tianjin Key Laboratory of Industrial Microbiology, Tianjin, China
- *Correspondence: Fuping Lu, ; Ming Li,
| |
Collapse
|
2
|
Bhardwaj N, Kumar B, Agrawal K, Verma P. Current perspective on production and applications of microbial cellulases: a review. BIORESOUR BIOPROCESS 2021; 8:95. [PMID: 38650192 PMCID: PMC10992179 DOI: 10.1186/s40643-021-00447-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/21/2021] [Indexed: 12/27/2022] Open
Abstract
The potential of cellulolytic enzymes has been widely studied and explored for bioconversion processes and plays a key role in various industrial applications. Cellulase, a key enzyme for cellulose-rich waste feedstock-based biorefinery, has increasing demand in various industries, e.g., paper and pulp, juice clarification, etc. Also, there has been constant progress in developing new strategies to enhance its production, such as the application of waste feedstock as the substrate for the production of individual or enzyme cocktails, process parameters control, and genetic manipulations for enzyme production with enhanced yield, efficiency, and specificity. Further, an insight into immobilization techniques has also been presented for improved reusability of cellulase, a critical factor that controls the cost of the enzyme at an industrial scale. In addition, the review also gives an insight into the status of the significant application of cellulase in the industrial sector, with its techno-economic analysis for future applications. The present review gives a complete overview of current perspectives on the production of microbial cellulases as a promising tool to develop a sustainable and greener concept for industrial applications.
Collapse
Affiliation(s)
- Nisha Bhardwaj
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
- Department of Chemical Engineering, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai, Maharashtra, 400019, India
| | - Bikash Kumar
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Komal Agrawal
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Pradeep Verma
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India.
| |
Collapse
|
3
|
Deepa P, Thirumeignanam D. Rising trend on the halogen and non-halogen derivatives (Br, Cl, CF 3, F, CH 3 and NH 2) in ruminal β-d-Xylopyranose - a quantum chemical perspective. J Biomol Struct Dyn 2020; 40:449-467. [PMID: 32880211 DOI: 10.1080/07391102.2020.1815577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The utmost aim of the current study is to find significance of the binding affinity in the halogen and non-halogen derivatives: Br, Cl, CF3, F, CH3 and NH2 of β-d-Xylopyranose with the hinge region amino acids of ruminant-β-glycosidase. The interaction energy analysis was carried out in detail through various density functional studies as M062X/def2-QZVP, M062X/LANL2DZ, B3LYP/LANL2DZ and M06HF/LANL2DZ level of theories. The total interaction energy of halogen derivatives: Br, Cl, F and CF3 are -618.21, -599.00, -720.45 and -553.08 kcal/mol respectively, and non-halogen derivative: amine group (NH2) is -87.96 kcal/mol at M062X/def2-QZVP level of theory, which exist with strong binding affinity. Ligand properties: dipole moment, polarizability, volume, molecular mass, electrostatic potential map was evaluated to understand its electrostatic and structural behavior. The nature of the bonds was inferred from the electrostatic potential map for all the halogen and non-halogen derivatives ligand. The stabilization energy from NBO analysis reveals the stability of single hydrogen and halogen bonds (N-H…Br, C-Br…O, N-H…Cl, C-Cl…O, O-H…F, C-H…F, N-H…F, C-F…O, N-H…O, O-H…O, N-H…N, O-H…N) in β-d-Xylopyranose and its derivatives. Overall, this study paves way for scientist and medicinal chemist in modelling new drugs. Further, it suggests mutations that increase the binding and may enhance the catalytic action and strengthen the complex diet in animals and hence recommended for experimental synthesis.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Palanisamy Deepa
- Department of Physics, Manonmaniam Sundaranar University, Tirunelveli, India
| | - Duraisamy Thirumeignanam
- Department of Animal Nutrition, Veterinary College and Research Institute, TamilNadu Veterinary and Animal Sciences University, Tirunelveli, India
| |
Collapse
|
4
|
Krogerus K, Gibson B. A re-evaluation of diastatic Saccharomyces cerevisiae strains and their role in brewing. Appl Microbiol Biotechnol 2020; 104:3745-3756. [PMID: 32170387 PMCID: PMC7162825 DOI: 10.1007/s00253-020-10531-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 03/02/2020] [Accepted: 03/05/2020] [Indexed: 12/14/2022]
Abstract
Abstract Diastatic strains of Saccharomyces cerevisiae possess the unique ability to hydrolyze and ferment long-chain oligosaccharides like dextrin and starch. They have long been regarded as important spoilage microbes in beer, but recent studies have inspired a re-evaluation of the significance of the group. Rather than being merely wild-yeast contaminants, they are highly specialized, domesticated yeasts belonging to a major brewing yeast lineage. In fact, many diastatic strains have unknowingly been used as production strains for decades. These yeasts are used in the production of traditional beer styles, like saison, but also show potential for creation of new beers with novel chemical and physical properties. Herein, we review results of the most recent studies and provide a detailed account of the structure, regulation, and functional role of the glucoamylase-encoding STA1 gene in relation to brewing and other fermentation industries. The state of the art in detecting diastatic yeast in the brewery is also summarized. In summary, these latest results highlight that having diastatic S. cerevisiae in your brewery is not necessarily a bad thing. Key Points •Diastatic S. cerevisiae strains are important spoilage microbes in brewery fermentations. •These strains belong to the ‘Beer 2’ or ‘Mosaic beer’ brewing yeast lineage. •Diastatic strains have unknowingly been used as production strains in breweries. •The STA1-encoded glucoamylase enables efficient maltotriose use. Electronic supplementary material The online version of this article (10.1007/s00253-020-10531-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Kristoffer Krogerus
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, P.O. Box 1000, FI-02044 VTT, Espoo, Finland.
| | - Brian Gibson
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, P.O. Box 1000, FI-02044 VTT, Espoo, Finland
| |
Collapse
|
5
|
Improved cellulase expression in diploid yeast strains enhanced consolidated bioprocessing of pretreated corn residues. Enzyme Microb Technol 2019; 131:109382. [DOI: 10.1016/j.enzmictec.2019.109382] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/27/2019] [Accepted: 07/12/2019] [Indexed: 01/12/2023]
|
6
|
Effects of intron retention on properties of β-glucosidase in Aspergillus niger. Fungal Biol 2019; 123:465-470. [DOI: 10.1016/j.funbio.2019.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 02/03/2019] [Accepted: 04/09/2019] [Indexed: 01/20/2023]
|
7
|
Meier-Dörnberg T, Kory OI, Jacob F, Michel M, Hutzler M. Saccharomyces cerevisiae variety diastaticus friend or foe?-spoilage potential and brewing ability of different Saccharomyces cerevisiae variety diastaticus yeast isolates by genetic, phenotypic and physiological characterization. FEMS Yeast Res 2019. [PMID: 29518233 DOI: 10.1093/femsyr/foy023] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Saccharomyces cerevisiae variety diastaticus is generally considered to be an obligatory spoilage microorganism and spoilage yeast in beer and beer-mixed beverages. Their super-attenuating ability causes increased carbon dioxide concentrations, beer gushing and potential bottle explosion along with changes in flavor, sedimentation and increased turbidity. This research shows clear differences in the super-attenuating properties of S. cerevisiae var. diastaticus yeast strains and their potential for industrial brewing applications. Nineteen unknown spoilage yeast cultures were obtained as isolates and characterized using a broad spectrum of genetic and phenotypic methods. Results indicated that all isolates represent genetically different S. cerevisiae var. diastaticus strains except for strain TUM PI BA 124. Yeast strains were screened for their super-attenuating ability and sporulation. Even if the STA1 gene responsible for super-attenuation by encoding for the enzyme glucoamylase could be verified by real-time polymerase chain reaction, no correlation to the spoilage potential could be demonstrated. Seven strains were further characterized focusing on brewing and sensory properties according to the yeast characterization platform developed by Meier-Dörnberg. Yeast strain TUM 3-H-2 cannot metabolize dextrin and soluble starch and showed no spoilage potential or super-attenuating ability even when the strain belongs to the species S. cerevisiae var. diastaticus. Overall, the beer produced with S. cerevisiae var. diastaticus has a dry and winey body with noticeable phenolic off-flavors desirable in German wheat beers.
Collapse
Affiliation(s)
- Tim Meier-Dörnberg
- Technical University of Munich, Research Center Weihenstephan for Brewing and Food Quality, Alte Akademie 3, 85354 Freising, Germany
| | - Oliver Ingo Kory
- Miho Inspektionssysteme GmbH, Obervellmarsche Str. 12, 334292 Ahnatal, Germany
| | - Fritz Jacob
- Technical University of Munich, Research Center Weihenstephan for Brewing and Food Quality, Alte Akademie 3, 85354 Freising, Germany
| | - Maximilian Michel
- Technical University of Munich, Research Center Weihenstephan for Brewing and Food Quality, Alte Akademie 3, 85354 Freising, Germany
| | - Mathias Hutzler
- Technical University of Munich, Research Center Weihenstephan for Brewing and Food Quality, Alte Akademie 3, 85354 Freising, Germany
| |
Collapse
|
8
|
Casa-Villegas M, Marín-Navarro J, Polaina J. Synthesis of Isomaltooligosaccharides by Saccharomyces cerevisiae Cells Expressing Aspergillus niger α-Glucosidase. ACS OMEGA 2017; 2:8062-8068. [PMID: 30023572 PMCID: PMC6045415 DOI: 10.1021/acsomega.7b01189] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/06/2017] [Indexed: 06/08/2023]
Abstract
The α-glucosidase encoded by the aglA gene of Aspergillus niger is a secreted enzyme belonging to family 31 of glycoside hydrolases. This enzyme has a retaining mechanism of action and displays transglycosylating activity that makes it amenable to be used for the synthesis of isomaltooligosaccharides (IMOs). We have expressed the aglA gene in Saccharomyces cerevisiae under control of a galactose-inducible promoter. Recombinant yeast cells expressing the aglA gene produced extracellular α-glucosidase activity about half of which appeared cell bound whereas the other half was released into the culture medium. With maltose as the substrate, panose is the main transglycosylation product after 8 h of incubation, whereas isomaltose is predominant after 24 h. Isomaltose also becomes predominant at shorter times if a mixture of maltose and glucose is used instead of maltose. To facilitate IMO production, we have designed a procedure by which yeast cells can be used directly as the catalytic agent. For this purpose, we expressed in S. cerevisiae gene constructs in which the aglA gene is fused to glycosylphosphatidylinositol anchor sequences, from the yeast SED1 gene, that determine the covalent binding of the hybrid protein to the cell membrane. The resulting hybrid enzymes were stably attached to the cell surface. The cells from cultures of recombinant yeast strains expressing aglA-SED1 constructions can be used to produce IMOs in successive batches.
Collapse
Affiliation(s)
- Mary Casa-Villegas
- Instituto
de Agroquímica y Tecnología de Alimentos, CSIC, 46980-Paterna, Valencia, Spain
| | - Julia Marín-Navarro
- Instituto
de Agroquímica y Tecnología de Alimentos, CSIC, 46980-Paterna, Valencia, Spain
- Departamento
de Bioquímica y Biología Molecular, Universidad de Valencia, 46100-Burjassot, Valencia, Spain
| | - Julio Polaina
- Instituto
de Agroquímica y Tecnología de Alimentos, CSIC, 46980-Paterna, Valencia, Spain
| |
Collapse
|
9
|
Synergies in coupled hydrolysis and fermentation of cellulose using a Trichoderma reesei enzyme preparation and a recombinant Saccharomyces cerevisiae strain. World J Microbiol Biotechnol 2017; 33:140. [DOI: 10.1007/s11274-017-2308-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/01/2017] [Indexed: 11/27/2022]
|
10
|
Ramírez-Escudero M, Del Pozo MV, Marín-Navarro J, González B, Golyshin PN, Polaina J, Ferrer M, Sanz-Aparicio J. Structural and Functional Characterization of a Ruminal β-Glycosidase Defines a Novel Subfamily of Glycoside Hydrolase Family 3 with Permuted Domain Topology. J Biol Chem 2016; 291:24200-24214. [PMID: 27679487 PMCID: PMC5104943 DOI: 10.1074/jbc.m116.747527] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/16/2016] [Indexed: 01/01/2023] Open
Abstract
Metagenomics has opened up a vast pool of genes for putative, yet uncharacterized, enzymes. It widens our knowledge on the enzyme diversity world and discloses new families for which a clear classification is still needed, as is exemplified by glycoside hydrolase family-3 (GH3) proteins. Herein, we describe a GH3 enzyme (GlyA1) from resident microbial communities in strained ruminal fluid. The enzyme is a β-glucosidase/β-xylosidase that also shows β-galactosidase, β-fucosidase, α-arabinofuranosidase, and α-arabinopyranosidase activities. Short cello- and xylo-oligosaccharides, sophorose and gentibiose, are among the preferred substrates, with the large polysaccharide lichenan also being hydrolyzed by GlyA1. The determination of the crystal structure of the enzyme in combination with deletion and site-directed mutagenesis allowed identification of its unusual domain composition and the active site architecture. Complexes of GlyA1 with glucose, galactose, and xylose allowed picturing the catalytic pocket and illustrated the molecular basis of the substrate specificity. A hydrophobic platform defined by residues Trp-711 and Trp-106, located in a highly mobile loop, appears able to allocate differently β-linked bioses. GlyA1 includes an additional C-terminal domain previously unobserved in GH3 members, but crystallization of the full-length enzyme was unsuccessful. Therefore, small angle x-ray experiments have been performed to investigate the molecular flexibility and overall putative shape. This study provided evidence that GlyA1 defines a new subfamily of GH3 proteins with a novel permuted domain topology. Phylogenetic analysis indicates that this topology is associated with microbes inhabiting the digestive tracts of ruminants and other animals, feeding on chemically diverse plant polymeric materials.
Collapse
Affiliation(s)
- Mercedes Ramírez-Escudero
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Mercedes V Del Pozo
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain
| | - Julia Marín-Navarro
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Beatriz González
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Peter N Golyshin
- the School of Biological Sciences, Bangor University, LL57 2UW Gwynedd, United Kingdom, and.,the Immanuel Kant Baltic Federal University, 236040 Kaliningrad, Russia
| | - Julio Polaina
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Manuel Ferrer
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain,
| | - Julia Sanz-Aparicio
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain,
| |
Collapse
|
11
|
Non-productive adsorption of bacterial β-glucosidases on lignins is electrostatically modulated and depends on the presence of fibronection type III-like domain. Enzyme Microb Technol 2016; 87-88:1-8. [PMID: 27178788 DOI: 10.1016/j.enzmictec.2016.02.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/11/2016] [Accepted: 02/12/2016] [Indexed: 01/09/2023]
Abstract
Non-productive adsorption of cellulases onto lignins is an important mechanism that negatively affects the enzymatic hydrolysis of lignocellulose biomass. Here, we examined the non-productive adsorption of two bacterial β-glucosidases (GH1 and GH3) on lignins. The results showed that β-glucosidases can adsorb to lignins through different mechanisms. GH1 β-glucosidase adsorption onto lignins was found to be strongly pH-dependent, suggesting that the adsorption is electrostatically modulated. For GH3 β-glucosidase, the results suggested that the fibronectin type III-like domain interacts with lignins through electrostatic and hydrophobic interactions that can partially, or completely, overcome repulsive electrostatic forces between the catalytic domain and lignins. Finally, the increase of temperature did not result in the increase of β-glucosidases adsorption, probably because there is no significant increase in hydrophobic regions in the β-glucosidases structures. The data provided here can be useful for biotechnological applications, especially in the field of plant structural polysaccharides conversion into bioenergy and bioproducts.
Collapse
|
12
|
Marín-Navarro J, Roupain N, Talens-Perales D, Polaina J. Identification and Structural Analysis of Amino Acid Substitutions that Increase the Stability and Activity of Aspergillus niger Glucose Oxidase. PLoS One 2015; 10:e0144289. [PMID: 26642312 PMCID: PMC4671603 DOI: 10.1371/journal.pone.0144289] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 11/16/2015] [Indexed: 11/30/2022] Open
Abstract
Glucose oxidase is one of the most conspicuous commercial enzymes due to its many different applications in diverse industries such as food, chemical, energy and textile. Among these applications, the most remarkable is the manufacture of glucose biosensors and in particular sensor strips used to measure glucose levels in serum. The generation of ameliorated versions of glucose oxidase is therefore a significant biotechnological objective. We have used a strategy that combined random and rational approaches to isolate uncharacterized mutations of Aspergillus niger glucose oxidase with improved properties. As a result, we have identified two changes that increase significantly the enzyme's thermal stability. One (T554M) generates a sulfur-pi interaction and the other (Q90R/Y509E) introduces a new salt bridge near the interphase of the dimeric protein structure. An additional double substitution (Q124R/L569E) has no significant effect on stability but causes a twofold increase of the enzyme's specific activity. Our results disclose structural motifs of the protein which are critical for its stability. The combination of mutations in the Q90R/Y509E/T554M triple mutant yielded a version of A. niger glucose oxidase with higher stability than those previously described.
Collapse
Affiliation(s)
- Julia Marín-Navarro
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - Nicole Roupain
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - David Talens-Perales
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - Julio Polaina
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| |
Collapse
|
13
|
Fitzpatrick J, Kricka W, James TC, Bond U. Expression of three Trichoderma reesei cellulase genes in Saccharomyces pastorianus for the development of a two-step process of hydrolysis and fermentation of cellulose. J Appl Microbiol 2014; 117:96-108. [PMID: 24666670 DOI: 10.1111/jam.12494] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 02/26/2014] [Accepted: 03/04/2014] [Indexed: 11/26/2022]
Abstract
AIMS To compare the production of recombinant cellulase enzymes in two Saccharomyces species so as to ascertain the most suitable heterologous host for the degradation of cellulose-based biomass and its conversion into bioethanol. METHOD AND RESULTS cDNA copies of genes representing the three major classes of cellulases (Endoglucanases, Cellobiohydrolases and β-glucosidases) from Trichoderma reesei were expressed in Saccharomyces pastorianus and Saccharomyces cerevisiae. The recombinant enzymes were secreted by the yeast hosts into the medium and were shown to act in synergy to hydrolyse cellulose. The conditions required to achieve maximum release of glucose from cellulose by the recombinant enzymes were defined and the activity of the recombinant enzymes was compared to a commercial cocktail of T. reesei cellulases. CONCLUSIONS We demonstrate that significantly higher levels of cellulase activity were achieved by expression of the genes in S. pastorianus compared to S. cerevisiae. Hydrolysis of cellulose by the combined activity of the recombinant enzymes was significantly better at 50°C than at 30°C, the temperature used for mesophilic yeast fermentations, reflecting the known temperature profiles of the native enzymes. SIGNIFICANCE AND IMPACT OF THE STUDY The results demonstrate that host choice is important for the heterologous production of cellulases. On the basis of the low activity of the T. reesei recombinant enzymes at fermentation temperatures, we propose a two-step process for the hydrolysis of cellulose and its fermentation into alcohol using cellulases produced in situ.
Collapse
Affiliation(s)
- J Fitzpatrick
- School of Genetics and Microbiology, Moyne Institute, Trinity College Dublin, College Green, Dublin 2, Ireland
| | | | | | | |
Collapse
|
14
|
Lima MA, Oliveira-Neto M, Kadowaki MAS, Rosseto FR, Prates ET, Squina FM, Leme AFP, Skaf MS, Polikarpov I. Aspergillus niger β-glucosidase has a cellulase-like tadpole molecular shape: insights into glycoside hydrolase family 3 (GH3) β-glucosidase structure and function. J Biol Chem 2013; 288:32991-3005. [PMID: 24064212 DOI: 10.1074/jbc.m113.479279] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aspergillus niger is known to secrete large amounts of β-glucosidases, which have a variety of biotechnological and industrial applications. Here, we purified an A. niger β-glucosidase (AnBgl1) and conducted its biochemical and biophysical analyses. Purified enzyme with an apparent molecular mass of 116 kDa forms monomers in solution as judged by native gel electrophoresis and has a pI value of 4.55, as found for most of the fungi of β-glucosidases. Surprisingly, the small angle x-ray experiments reveal that AnBgl1 has a tadpole-like structure, with the N-terminal catalytic domain and C-terminal fibronectin III-like domain (FnIII) connected by the long linker peptide (∼100 amino acid residues) in an extended conformation. This molecular organization resembles the one adopted by other cellulases (such as cellobiohydrolases, for example) that frequently contain a catalytic domain linked to the cellulose-binding module that mediates their binding to insoluble and polymeric cellulose. The reasons why AnBgl1, which acts on the small soluble substrates, has a tadpole molecular shape are not entirely clear. However, our enzyme pulldown assays with different polymeric substrates suggest that AnBgl1 has little or no capacity to bind to and to adsorb cellulose, xylan, and starch, but it has high affinity to lignin. Molecular dynamics simulations suggested that clusters of residues located in the C-terminal FnIII domain interact strongly with lignin fragments. The simulations showed that numerous arginine residues scattered throughout the FnIII surface play an important role in the interaction with lignin by means of cation-π stacking with the lignin aromatic rings. These results indicate that the C-terminal FnIII domain could be operational for immobilization of the enzyme on the cell wall and for the prevention of unproductive binding of cellulase to the biomass lignin.
Collapse
Affiliation(s)
- Marisa A Lima
- From the Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos 13560-970, SP
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Gómez MD, Renau-Morata B, Roque E, Polaina J, Beltrán JP, Cañas LA. PsPMEP, a pollen-specific pectin methylesterase of pea (Pisum sativum L.). PLANT REPRODUCTION 2013; 26:245-54. [PMID: 23839307 DOI: 10.1007/s00497-013-0220-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 06/23/2013] [Indexed: 05/23/2023]
Abstract
Pectin methylesterases (PMEs) are a family of enzymes involved in plant reproductive processes such as pollen development and pollen tube growth. We have isolated and characterized PsPMEP, a pea (Pisum sativum L.) pollen-specific gene that encodes a protein with homology to PMEs. Sequence analysis showed that PsPMEP belongs to group 2 PMEs, which are characterized by the presence of a processable amino-terminal PME inhibitor domain followed by the catalytic PME domain. Moreover, PsPMEP contains several motifs highly conserved among PMEs with the essential amino acid residues involved in enzyme substrate binding and catalysis. Northern blot and in situ hybridization analyses showed that PsPMEP is expressed in pollen grains from 4 days before anthesis till anther dehiscence and in pollinated carpels. In the PsPMEP promoter region, we have identified several conserved cis-regulatory elements that have been associated with gene pollen-specific expression. Expression analysis of PsPMEP promoter fused to the uidA reporter gene in Arabidopsis thaliana plants showed a similar expression pattern when compared with pea, indicating that this promoter is also functional in a non-leguminous plant. GUS expression was detected in mature pollen grains, during pollen germination, during pollen tube elongation along the transmitting tract, and when the pollen tube reaches the embryo sac in the ovule.
Collapse
Affiliation(s)
- María Dolores Gómez
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), Ciudad Politécnica de la Innovación, Edf. 8E. C/, Ingeniero Fausto Elio s/n, 46011, Valencia, Spain
| | | | | | | | | | | |
Collapse
|
16
|
Del Pozo MV, Fernández-Arrojo L, Gil-Martínez J, Montesinos A, Chernikova TN, Nechitaylo TY, Waliszek A, Tortajada M, Rojas A, Huws SA, Golyshina OV, Newbold CJ, Polaina J, Ferrer M, Golyshin PN. Microbial β-glucosidases from cow rumen metagenome enhance the saccharification of lignocellulose in combination with commercial cellulase cocktail. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:73. [PMID: 22998985 PMCID: PMC3477023 DOI: 10.1186/1754-6834-5-73] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/14/2012] [Indexed: 05/07/2023]
Abstract
BACKGROUND A complete saccharification of plant polymers is the critical step in the efficient production of bio-alcohols. Beta-glucosidases acting in the degradation of intermediate gluco-oligosaccharides produced by cellulases limit the yield of the final product. RESULTS In the present work, we have identified and then successfully cloned, expressed, purified and characterised 4 highly active beta-glucosidases from fibre-adherent microbial community from the cow rumen. The enzymes were most active at temperatures 45-55°C and pH 4.0-7.0 and exhibited high affinity and activity towards synthetic substrates such as p-nitrophenyl-beta-D-glucopyranoside (pNPbetaG) and pNP-beta-cellobiose, as well as to natural cello-oligosaccharides ranging from cellobiose to cellopentaose. The apparent capability of the most active beta-glucosidase, herein named LAB25g2, was tested for its ability to improve, at low dosage (31.25 units g-1 dry biomass, using pNPbetaG as substrate), the hydrolysis of pre-treated corn stover (dry matter content of 20%; 350 g glucan kg-1 dry biomass) in combination with a beta-glucosidase-deficient commercial Trichoderma reseei cellulase cocktail (5 units g-1 dry biomass in the basis of pNPbetaG). LAB25g2 increased the final hydrolysis yield by a factor of 20% (44.5 ± 1.7% vs. 34.5 ± 1.5% in control conditions) after 96-120 h as compared to control reactions in its absence or in the presence of other commercial beta-glucosidase preparations. The high stability (half-life higher than 5 days at 50°C and pH 5.2) and 2-38000 fold higher (as compared with reported beta-glucosidases) activity towards cello-oligosaccharides may account for its performance in supplementation assays. CONCLUSIONS The results suggest that beta-glucosidases from yet uncultured bacteria from animal digestomes may be of a potential interest for biotechnological processes related to the effective bio-ethanol production in combination with low dosage of commercial cellulases.
Collapse
Affiliation(s)
| | | | | | | | | | - Taras Y Nechitaylo
- Insect Symbiosis Research Group, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Agnes Waliszek
- Environmental Microbiology Department, HZI-Helmholtz Centre for Infection Research, D-38124, Braunschweig, Germany
| | | | | | - Sharon A Huws
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3DA, UK
| | - Olga V Golyshina
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
| | - Charles J Newbold
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3DA, UK
- Centre for Integrated Research in the Rural Environment, Aberystwyth University-Bangor University Partnership (CIRRE), Aberystwyth, SY23 3DA, UK
| | - Julio Polaina
- CSIC, Instituto de Agroquímica y Tecnología de Alimentos, 46980, Paterna, Valencia, Spain
| | | | - Peter N Golyshin
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
- Centre for Integrated Research in the Rural Environment, Aberystwyth University-Bangor University Partnership (CIRRE), Aberystwyth, SY23 3DA, UK
| |
Collapse
|
17
|
Gurgu L, Lafraya Á, Polaina J, Marín-Navarro J. Fermentation of cellobiose to ethanol by industrial Saccharomyces strains carrying the β-glucosidase gene (BGL1) from Saccharomycopsis fibuligera. BIORESOURCE TECHNOLOGY 2011; 102:5229-36. [PMID: 21324680 DOI: 10.1016/j.biortech.2011.01.062] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 01/18/2011] [Accepted: 01/19/2011] [Indexed: 05/23/2023]
Abstract
Constructs carrying the Saccharomycopsis fibuligera β-glucosidase gene (BGL1) under the control of a constitutive actin or a galactose-inducible promoter were introduced into eleven Saccharomyces strains. In ten of these recombinant strains, BGL1 expression driven by the actin promoter was between 1.6- and 18-fold higher than that obtained with the galactose-inducible promoter. Strains carrying the actin promoter yielded ethanol concentrations from cellobiose of between 0.5% and 14%, depending on their ability to accumulate Bgl1 (between 30 and 250 mU/mL) but also on their genetic background. Comparative analysis of a S. cerevisiae strain and its corresponding petite version showed similar ethanol yields, despite a 3-fold lower β-glucosidase production of the latter, suggesting that respiratory activity could be one of the factors influencing ethanol production when using carbon sources other than glucose. This study provides a selection of strains that may be good candidates as hosts for ethanol biosynthesis from cellulosic substrates.
Collapse
Affiliation(s)
- Leontina Gurgu
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, CSIC, Paterna, Valencia, Spain
| | | | | | | |
Collapse
|
18
|
Glucoamylases: structural and biotechnological aspects. Appl Microbiol Biotechnol 2010; 89:1267-73. [DOI: 10.1007/s00253-010-3034-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Revised: 11/22/2010] [Accepted: 11/23/2010] [Indexed: 11/26/2022]
|