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Buetti-Dinh A, Ruinelli M, Czerski D, Scapozza C, Martignier A, Roman S, Caminada A, Tonolla M. Geochemical and metagenomics study of a metal-rich, green-turquoise-coloured stream in the southern Swiss Alps. PLoS One 2021; 16:e0248877. [PMID: 33784327 PMCID: PMC8009434 DOI: 10.1371/journal.pone.0248877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 03/07/2021] [Indexed: 12/02/2022] Open
Abstract
The Swiss Alpine environments are poorly described from a microbiological perspective. Near the Greina plateau in the Camadra valley in Ticino (southern Swiss Alps), a green-turquoise-coloured water spring streams off the mountain cliffs. Geochemical profiling revealed naturally elevated concentrations of heavy metals such as copper, lithium, zinc and cadmium, which are highly unusual for the geomorphology of the region. Of particular interest, was the presence of a thick biofilm, that was revealed by microscopic analysis to be mainly composed of Cyanobacteria. A metagenome was further assembled to detail the genes found in this environment. A multitude of genes for resistance/tolerance to high heavy metal concentrations were indeed found, such as, various transport systems, and genes involved in the synthesis of extracellular polymeric substances (EPS). EPS have been evoked as a central component in photosynthetic environments rich in heavy metals, for their ability to drive the sequestration of toxic, positively-charged metal ions under high regimes of cyanobacteria-driven photosynthesis. The results of this study provide a geochemical and microbiological description of this unusual environment in the southern Swiss Alps, the role of cyanobacterial photosynthesis in metal resistance, and the potential role of such microbial community in bioremediation of metal-contaminated environments.
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Affiliation(s)
- Antoine Buetti-Dinh
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
- * E-mail: (ABD); (MT)
| | - Michela Ruinelli
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Dorota Czerski
- Institute of Earth Sciences, University of Applied Sciences of Southern Switzerland (SUPSI), Trevano, Canobbio, Switzerland
| | - Cristian Scapozza
- Institute of Earth Sciences, University of Applied Sciences of Southern Switzerland (SUPSI), Trevano, Canobbio, Switzerland
| | - Agathe Martignier
- Department of Earth Sciences, University of Geneva, Geneva, Switzerland
| | - Samuele Roman
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
| | - Annapaola Caminada
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Mauro Tonolla
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- * E-mail: (ABD); (MT)
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Park H, Patel A, Hunt KA, Henson MA, Carlson RP. Artificial consortium demonstrates emergent properties of enhanced cellulosic-sugar degradation and biofuel synthesis. NPJ Biofilms Microbiomes 2020; 6:59. [PMID: 33268782 PMCID: PMC7710750 DOI: 10.1038/s41522-020-00170-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 10/23/2020] [Indexed: 01/03/2023] Open
Abstract
Planktonic cultures, of a rationally designed consortium, demonstrated emergent properties that exceeded the sums of monoculture properties, including a >200% increase in cellobiose catabolism, a >100% increase in glycerol catabolism, a >800% increase in ethanol production, and a >120% increase in biomass productivity. The consortium was designed to have a primary and secondary-resource specialist that used crossfeeding with a positive feedback mechanism, division of labor, and nutrient and energy transfer via necromass catabolism. The primary resource specialist was Clostridium phytofermentans (a.k.a. Lachnoclostridium phytofermentans), a cellulolytic, obligate anaerobe. The secondary-resource specialist was Escherichia coli, a versatile, facultative anaerobe, which can ferment glycerol and byproducts of cellobiose catabolism. The consortium also demonstrated emergent properties of enhanced biomass accumulation when grown as biofilms, which created high cell density communities with gradients of species along the vertical axis. Consortium biofilms were robust to oxic perturbations with E. coli consuming O2, creating an anoxic environment for C. phytofermentans. Anoxic/oxic cycling further enhanced biomass productivity of the biofilm consortium, increasing biomass accumulation ~250% over the sum of the monoculture biofilms. Consortium emergent properties were credited to several synergistic mechanisms. E. coli consumed inhibitory byproducts from cellobiose catabolism, driving higher C. phytofermentans growth and higher cellulolytic enzyme production, which in turn provided more substrate for E. coli. E. coli necromass enhanced C. phytofermentans growth while C. phytofermentans necromass aided E. coli growth via the release of peptides and amino acids, respectively. In aggregate, temporal cycling of necromass constituents increased flux of cellulose-derived resources through the consortium. The study establishes a consortia-based, bioprocessing strategy built on naturally occurring interactions for improved conversion of cellulose-derived sugars into bioproducts.
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Affiliation(s)
- Heejoon Park
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.,Department of Engineering and Technology, University of North Alabama, Florence, AL, USA
| | - Ayushi Patel
- Department of Chemical Engineering and Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA, USA
| | - Kristopher A Hunt
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.,Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - Michael A Henson
- Department of Chemical Engineering and Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA, USA
| | - Ross P Carlson
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA. .,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
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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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Gandini C, Tarraran L, Kalemasi D, Pessione E, Mazzoli R. RecombinantLactococcus lactisfor efficient conversion of cellodextrins into L-lactic acid. Biotechnol Bioeng 2017; 114:2807-2817. [DOI: 10.1002/bit.26400] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/01/2017] [Accepted: 08/07/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Chiara Gandini
- Department of Life Sciences and Systems Biology, Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes; University of Turin; Torino Italy
| | - Loredana Tarraran
- Department of Life Sciences and Systems Biology, Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes; University of Turin; Torino Italy
| | - Denis Kalemasi
- Department of Life Sciences and Systems Biology, Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes; University of Turin; Torino Italy
| | - Enrica Pessione
- Department of Life Sciences and Systems Biology, Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes; University of Turin; Torino Italy
| | - Roberto Mazzoli
- Department of Life Sciences and Systems Biology, Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes; University of Turin; Torino Italy
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Szydlowski L, Boschetti C, Crisp A, Barbosa E, Tunnacliffe A. Multiple horizontally acquired genes from fungal and prokaryotic donors encode cellulolytic enzymes in the bdelloid rotifer Adineta ricciae. Gene 2015; 566:125-37. [DOI: 10.1016/j.gene.2015.04.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 04/01/2015] [Accepted: 04/03/2015] [Indexed: 10/23/2022]
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A noncellulosomal mannanase26E contains a CBM59 in Clostridium cellulovorans. BIOMED RESEARCH INTERNATIONAL 2014; 2014:438787. [PMID: 24795881 PMCID: PMC3985142 DOI: 10.1155/2014/438787] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/18/2014] [Indexed: 11/17/2022]
Abstract
A multicomponent enzyme-complex prevents efficient degradation of the plant cell wall for biorefinery. In this study, the method of identifying glycoside hydrolases (GHs) to degrade hemicelluloses was demonstrated. The competence of C. cellulovorans, which changes to be suitable for degradation of each carbon source, was used for the method. C. cellulovorans was cultivated into locust bean gum (LBG) that is composed of galactomannan. The proteins produced by C. cellulovorans were separated into either fractions binding to crystalline cellulose or not. Proteins obtained from each fraction were further separated by SDS-PAGE and were stained with Coomassie Brilliant Blue and were detected for mannanase activity. The proteins having the enzymatic activity for LBG were cut out and were identified by mass spectrometry. As a result, four protein bands were classified into glycosyl hydrolase family 26 (GH26) mannanases. One of the identified mannanases, Man26E, contains a carbohydrate-binding module (CBM) family 59, which binds to xylan, mannan, and Avicel. Although mannose and galactose are the same as a hexose, the expression patterns of the proteins from C. cellulovorans were quite different. More interestingly, zymogram for mannanase activity showed that Man26E was detected in only LBG medium.
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Zhao Z, Ramachandran P, Kim TS, Chen Z, Jeya M, Lee JK. Characterization of an acid-tolerant β-1,4-glucosidase from Fusarium oxysporum and its potential as an animal feed additive. Appl Microbiol Biotechnol 2013; 97:10003-11. [PMID: 23604557 DOI: 10.1007/s00253-013-4767-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 02/07/2013] [Accepted: 02/09/2013] [Indexed: 10/26/2022]
Abstract
An extracellular β-glucosidase (BGL) from Fusarium oxysporum was purified to homogeneity by a single chromatography step on a gel filtration column. The optimum activity of BGL on cellobiose was observed at pH 5.0 and 60 °C. Under the same conditions, the K(m) and V(max) values for p-nitrophenyl β-D-glucopyranoside and cellobiose were 2.53 mM, 268 U mg protein(-1) and 20.3 mM, 193 U mg protein(-1), respectively. The F. oxysporum BGL enzyme was highly stable at acidic pH (t 1/2 = 470 min at pH 3). A commercial BGL Novo188 (Novozymes) and F. oxysporum BGL were compared in their ability to supplement Celluclast 1.5 L (Novozymes). In comparison with the commercial Novo188 (267 mg g substrate(-1)), F. oxysporum BGL supplementation released more reducing sugars (330 mg g substrate(-1)) from cellulose under simulated gastric conditions. These properties make F. oxysporum BGL a good candidate as a new commercial BGL to improve the nutrient bioavailability of animal feed.
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Affiliation(s)
- Zongpei Zhao
- Department of Chemical Engineering, Konkuk University, Seoul, 143-701, Republic of Korea
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Mutations in the substrate entrance region of -glucosidase from Trichoderma reesei improve enzyme activity and thermostability. Protein Eng Des Sel 2012; 25:733-40. [DOI: 10.1093/protein/gzs073] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Creation of a cellooligosaccharide-assimilating Escherichia coli strain by displaying active beta-glucosidase on the cell surface via a novel anchor protein. Appl Environ Microbiol 2011; 77:6265-70. [PMID: 21742905 DOI: 10.1128/aem.00459-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We demonstrated direct assimilation of cellooligosaccharide using Escherichia coli displaying beta-glucosidase (BGL). BGL from Thermobifida fusca YX (Tfu0937) was displayed on the E. coli cell surface using a novel anchor protein named Blc. This strain was grown successfully on 0.2% cellobiose, and the optical density at 600 nm (OD(600)) was 1.05 after 20 h.
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Hydrolysis of cellulose in synergistic mixtures of β-glucosidase and endo/exocellulase Cel9A from Thermobifida fusca. Biotechnol Lett 2010; 33:777-82. [DOI: 10.1007/s10529-010-0500-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 12/08/2010] [Indexed: 10/18/2022]
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Jeng WY, Wang NC, Lin MH, Lin CT, Liaw YC, Chang WJ, Liu CI, Liang PH, Wang AHJ. Structural and functional analysis of three β-glucosidases from bacterium Clostridium cellulovorans, fungus Trichoderma reesei and termite Neotermes koshunensis. J Struct Biol 2010; 173:46-56. [PMID: 20682343 DOI: 10.1016/j.jsb.2010.07.008] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 07/17/2010] [Accepted: 07/29/2010] [Indexed: 11/18/2022]
Abstract
β-glucosidases (EC 3.2.1.21) cleave β-glucosidic linkages in disaccharide or glucose-substituted molecules and play important roles in fundamental biological processes. β-Glucosidases have been widely used in agricultural, biotechnological, industrial and medical applications. In this study, a high yield expression (70-250 mg/l) in Escherichia coli of the three functional β-glucosidase genes was obtained from the bacterium Clostridium cellulovorans (CcBglA), the fungus Trichoderma reesei (TrBgl2), and the termite Neotermes koshunensis (NkBgl) with the crystal structures of CcBglA, TrBgl2 and NkBgl, determined at 1.9Å, 1.63Å and 1.34Å resolution, respectively. The overall structures of these enzymes are similar to those belonging to the β-retaining glycosyl hydrolase family 1, which have a classical (α/β)(8)-TIM barrel fold. Each contains a slot-like active site cleft and a more variable outer opening, related to its function in processing different lengths of β-1,4-linked glucose derivatives. The two essential glutamate residues for hydrolysis are spatially conserved in the active site. In both TrBgl2 and NkBgl structures, a Tris molecule was found to bind at the active site, explaining the slight inhibition of hydrolase activity observed in Tris buffer. Manganese ions at 10mM exerted an approximate 2-fold enzyme activity enhancement of all three β-glucosidases, with CcBglA catalyzing the most efficiently in hydrolysis reaction and tolerating Tris as well as some metal inhibition. In summary, our results for the structural and functional properties of these three β-glucosidases from various biological sources open important avenues of exploration for further practical applications.
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Affiliation(s)
- Wen-Yih Jeng
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
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Tamaru Y, Miyake H, Kuroda K, Ueda M, Doi RH. Comparative genomics of the mesophilic cellulosome-producing Clostridium cellulovorans and its application to biofuel production via consolidated bioprocessing. ENVIRONMENTAL TECHNOLOGY 2010; 31:889-903. [PMID: 20662379 DOI: 10.1080/09593330.2010.490856] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Clostridium cellulovorans is an anaerobic, mesophilic bacterium that efficiently degrades native substrates in soft biomass such as corn fibre and rice straw by producing an extracellular enzyme complex called the cellulosomes. By examining genome sequences from multiple Clostridium species, comparative genomics offers new insight into genome evolution and the way natural selection moulds functional DNA sequence evolution. Recently, we reported the whole genome sequence of C. cellulovorans. A total of 57 cellulosomal genes were found in the C. cellulovorans genome and coded for not only carbohydrate-active enzymes but also lipase, peptidase and proteinase inhibitors, in addition to two novel genes encoding scaffolding proteins CbpB and CbpC. Interestingly, the genome size of C. cellulovorans was about 1 Mbp larger than that of other cellulosome-producing clostridia: mesophilic C. cellulolyticum and thermophilic C. thermocellum. Since the C. cellulovorans genome included not only cellulosomal genes but also a large number of genes encoding non-cellulosomal enzymes, the genome expansion of C. cellulovorans included genes more related to degradation of polysaccharides, such as hemicelluloses and pectins, than to cellulose. In this review, we propose a strategy for industrial applications such as biofuel production using enhanced mesophilic cellulosome- and solvent-producing clostridia.
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Affiliation(s)
- Yutaka Tamaru
- Department of Life Science, Mie University Graduate School of Bioresourses, 1577 Kurimamachiya, Tsu, Mie 514-8507, Japan.
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Cel9D, an atypical 1,4-beta-D-glucan glucohydrolase from Fibrobacter succinogenes: characteristics, catalytic residues, and synergistic interactions with other cellulases. J Bacteriol 2008; 190:1976-84. [PMID: 18203823 DOI: 10.1128/jb.01667-07] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The increasing demands of renewable energy have led to the critical emphasis on novel enzymes to enhance cellulose biodegradation for biomass conversion. To identify new cellulases in the ruminal bacterium Fibrobacter succinogenes, a cell extract of cellulose-grown cells was separated by ion-exchange chromatography and cellulases were located by zymogram analysis and identified by peptide mass fingerprinting. An atypical family 9 glycoside hydrolase (GH9), Cel9D, with less than 20% identity to typical GH9 cellulases, was identified. Purified recombinant Cel9D enhanced the production of reducing sugar from acid swollen cellulose (ASC) and Avicel by 1.5- to 4-fold when mixed separately with each of four other glucanases, although it had low activity on these substrates. Cel9D degraded ASC and cellodextrins with a degree of polymerization higher than 2 to glucose with no apparent endoglucanase activity, and its activity was restricted to beta-1-->4-linked glucose residues. It catalyzed the hydrolysis of cellulose by an inverting mode of reaction, releasing glucose from the nonreducing end. Unlike many GH9 cellulases, calcium ions were not required for its function. Cel9D had increased kcat/Km values for cello-oligosaccharides with higher degrees of polymerization. The kcat/Km value for cellohexaose was 2,300 times higher than that on cellobiose. This result indicates that Cel9D is a 1,4-beta-D-glucan glucohydrolase (EC 3.2.1.74) in the GH9 family. Site-directed mutagenesis of Cel9D identified Asp166 and Glu612 as the candidate catalytic residues, while Ser168, which is not present in typical GH9 cellulases, has a crucial structural role. This enzyme has an important role in crystalline cellulose digestion by releasing glucose from accessible cello-oligosaccharides.
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Construction and characterization of a clostripain-like protease-deficient mutant of Clostridium perfringens as a strain for clostridial gene expression. Appl Microbiol Biotechnol 2008; 77:1063-71. [DOI: 10.1007/s00253-007-1245-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Revised: 10/05/2007] [Accepted: 10/08/2007] [Indexed: 12/14/2022]
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Doi RH. Cellulases of mesophilic microorganisms: cellulosome and noncellulosome producers. Ann N Y Acad Sci 2007; 1125:267-79. [PMID: 18096849 DOI: 10.1196/annals.1419.002] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The cellulolytic activity of mesophilic bacteria and fungi is described, with special emphasis on the large extracellular enzyme complex called the cellulosome. The cellulosome is composed of a scaffolding protein, which is attached to various cellulolytic and hemicellulolytic enzymes, and this complex allows the organisms to degrade plant cell walls very efficently. The enzymes include a variety of cellulases, hemicellulases, and pectinases that work synergistically to degrade complex cell-wall molecules.
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Affiliation(s)
- Roy H Doi
- Section of Molecular and Cellular Biology, University of California, One Shields Avenue, Davis, CA 95616, USA.
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