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Metreveli E, Khardziani T, Elisashvili V. The Carbon Source Controls the Secretion and Yield of Polysaccharide-Hydrolyzing Enzymes of Basidiomycetes. Biomolecules 2021; 11:biom11091341. [PMID: 34572556 PMCID: PMC8466102 DOI: 10.3390/biom11091341] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/03/2021] [Accepted: 09/07/2021] [Indexed: 11/23/2022] Open
Abstract
In the present study, the polysaccharide-hydrolyzing secretomes of Irpex lacteus (Fr.) Fr. (1828) BCC104, Pycnoporus coccineus (Fr.) Bondartsev and Singer (1941) BCC310, and Schizophyllum commune Fr. (1815) BCC632 were analyzed in submerged fermentation conditions to elucidate the effect of chemically and structurally different carbon sources on the expression of cellulases and xylanase. Among polymeric substrates, crystalline cellulose appeared to be the best carbon source providing the highest endoglucanase, total cellulase, and xylanase activities. Mandarin pomace as a growth substrate for S. commune allowed to achieve comparatively high volumetric activities of all target enzymes while wheat straw induced a significant secretion of cellulase and xylanase activities of I. lacteus and P. coccineus. An additive effect on the secretion of cellulases and xylanases by the tested fungi was observed when crystalline cellulose was combined with mandarin pomace. In I. lacteus the cellulase and xylanase production is inducible in the presence of cellulose-rich substrates but is suppressed in the presence of an excess of easily metabolizable carbon source. These enzymes are expressed in a coordinated manner under all conditions studied. It was shown that the substitution of glucose in the inoculum medium with Avicel provides accelerated enzyme production by I. lacteus and higher cellulase and xylanase activities of the fungus. These results add new knowledge to the physiology of basidiomycetes to improve cellulase production.
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Lin MC, Kuo HW, Kao MR, Lin WD, Li CW, Hung KS, Yang SC, Yu SM, Ho THD. From simple and specific zymographic detections to the annotation of a fungus Daldinia caldariorum D263 that encodes a wide range of highly bioactive cellulolytic enzymes. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:120. [PMID: 34020690 PMCID: PMC8140500 DOI: 10.1186/s13068-021-01959-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Lignocellulolytic enzymes are essential for agricultural waste disposal and production of renewable bioenergy. Many commercialized cellulase mixtures have been developed, mostly from saprophytic or endophytic fungal species. The cost of complete cellulose digestion is considerable because a wide range of cellulolytic enzymes is needed. However, most fungi can only produce limited range of highly bioactive cellulolytic enzymes. We aimed to investigate a simple yet specific method for discovering unique enzymes so that fungal species producing a diverse group of cellulolytic enzymes can be identified. RESULTS The culture medium of an endophytic fungus, Daldinia caldariorum D263, contained a complete set of cellulolytic enzymes capable of effectively digesting cellulose residues into glucose. By taking advantage of the unique product inhibition property of β-glucosidases, we have established an improved zymography method that can easily distinguish β-glucosidase and exoglucanase activity. Our zymography method revealed that D263 can secrete a wide range of highly bioactive cellulases. Analyzing the assembled genome of D263, we found over 100 potential genes for cellulolytic enzymes that are distinct from those of the commercially used fungal species Trichoderma reesei and Aspergillus niger. We further identified several of these cellulolytic enzymes by mass spectrometry. CONCLUSIONS The genome of Daldinia caldariorum D263 has been sequenced and annotated taking advantage of a simple yet specific zymography method followed by mass spectrometry analysis, and it appears to encode and secrete a wide range of bioactive cellulolytic enzymes. The genome and cellulolytic enzyme secretion of this unique endophytic fungus should be of value for identifying active cellulolytic enzymes that can facilitate conversion of agricultural wastes to fermentable sugars for the industrial production of biofuels.
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Affiliation(s)
- Meng-Chun Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Hsion-Wen Kuo
- Department of Environmental Science and Engineering, Tunghai University, Taichung, Taiwan, ROC
| | - Mu-Rong Kao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Wen-Dar Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Chen-Wei Li
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Kuo-Sheng Hung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Sheng-Chih Yang
- Institute of Tropical Plant Science, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Research Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Tuan-Hua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC.
- Biotechnology Research Center, National Chung Hsing University, Taichung, Taiwan, ROC.
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β-Xylosidases: Structural Diversity, Catalytic Mechanism, and Inhibition by Monosaccharides. Int J Mol Sci 2019; 20:ijms20225524. [PMID: 31698702 PMCID: PMC6887791 DOI: 10.3390/ijms20225524] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 12/20/2022] Open
Abstract
Xylan, a prominent component of cellulosic biomass, has a high potential for degradation into reducing sugars, and subsequent conversion into bioethanol. This process requires a range of xylanolytic enzymes. Among them, β-xylosidases are crucial, because they hydrolyze more glycosidic bonds than any of the other xylanolytic enzymes. They also enhance the efficiency of the process by degrading xylooligosaccharides, which are potent inhibitors of other hemicellulose-/xylan-converting enzymes. On the other hand, the β-xylosidase itself is also inhibited by monosaccharides that may be generated in high concentrations during the saccharification process. Structurally, β-xylosidases are diverse enzymes with different substrate specificities and enzyme mechanisms. Here, we review the structural diversity and catalytic mechanisms of β-xylosidases, and discuss their inhibition by monosaccharides.
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Quattrini M, Korcari D, Ricci G, Fortina MG. A polyphasic approach to characterize Weissella cibaria and Weissella confusa strains. J Appl Microbiol 2019; 128:500-512. [PMID: 31602728 DOI: 10.1111/jam.14483] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 10/07/2019] [Accepted: 10/07/2019] [Indexed: 02/04/2023]
Abstract
AIM To study Weissella cibaria and Weissella confusa strains, lactic acid bacteria (LAB) members naturally present in food products, but not yet included in Qualified Presumption of Safety (QPS) list of European Food Safety Authority (EFSA). METHODS AND RESULTS We carried out a comparative genome analysis of 23 sequenced W. cibaria and 7 W. confusa genomes, in parallel with a physiological and functional characterization of several strains previously isolated from sourdough-like maize bran fermentation. The genome analysis revealed the absence of dedicated pathogenicity factors. Some putative virulence genes found in Weissella genomes were also present in other LAB strains, considered safe by EFSA and commonly used as probiotics. The physiological tests carried out on our strains corroborated the genomic results. Moreover, the following functional traits of interest to application in the food sector were identified: the majority of tested strains displayed high acidification rate, high reducing ability, production of exopolysaccharides (EPS), arabinoxylan degradation ability, growth in the presence of fructo-oligosaccharides (FOS), bile and gastric juice tolerance, and antifungal activity. CONCLUSIONS These results provide evidence for the possible use of selected strains of W. cibaria and W. confusa in the food sector. SIGNIFICANCE AND IMPACT OF THE STUDY This polyphasic study adds to the body of knowledge on the functional and applicable characteristics of these controversial species of LAB. This knowledge contributes to design new selected cultures included in the QPS list required for food applications.
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Affiliation(s)
- M Quattrini
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, Milan, Italy
| | - D Korcari
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, Milan, Italy
| | - G Ricci
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, Milan, Italy
| | - M G Fortina
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, Milan, Italy
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Schmuck B, Gudmundsson M, Härd T, Sandgren M. Coupled chemistry kinetics demonstrate the utility of functionalized Sup35 amyloid nanofibrils in biocatalytic cascades. J Biol Chem 2019; 294:14966-14977. [PMID: 31416835 PMCID: PMC6791322 DOI: 10.1074/jbc.ra119.008455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 08/14/2019] [Indexed: 01/06/2023] Open
Abstract
Concerns over the environment are a central driver for designing cell-free enzymatic cascade reactions that synthesize non-petrol-based commodity compounds. An often-suggested strategy that would demonstrate the economic competitiveness of this technology is recycling of valuable enzymes through their immobilization. For this purpose, amyloid nanofibrils are an ideal scaffold to realize chemistry-free covalent enzyme immobilization on a material that offers a large surface area. However, in most instances, only single enzyme-functionalized amyloid fibrils have so far been studied. To embark on the next stage, here we displayed xylanase A, β-xylosidase, and an aldose sugar dehydrogenase on Sup35(1-61) nanofibrils to convert beechwood xylan to xylonolactone. We characterized this enzymatic cascade by measuring the time-dependent accumulation of xylose, xylooligomers, and xylonolactone. Furthermore, we studied the effects of relative enzyme concentrations, pH, temperature, and agitation on product formation. Our investigations revealed that a modular cascade with a mixture of xylanase and β-xylosidase, followed by product removal and separate oxidation of xylose with the aldose sugar dehydrogenase, is more productive than an enzyme mix containing all of these enzymes together. Moreover, we found that the nanofibril-coupled enzymes do not lose activity compared with their native state. These findings provide proof of concept of the feasibility of functionalized Sup35(1-61) fibrils as a molecular scaffold for biocatalytic cascades consisting of reusable enzymes that can be used in biotechnology.
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Affiliation(s)
- Benjamin Schmuck
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Mikael Gudmundsson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Torleif Härd
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
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Liu S, Ma C, Liu L, Ning D, Liu Y, Dong B. β-xylosidase and β-mannosidase in combination improved growth performance and altered microbial profiles in weanling pigs fed a corn-soybean meal-based diet. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2019; 32:1734-1744. [PMID: 31010999 PMCID: PMC6817776 DOI: 10.5713/ajas.18.0873] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 02/06/2019] [Indexed: 11/27/2022]
Abstract
Objective In this study, two glycosidases (XMosidases), β-xylosidase and β-mannosidase, were investigated on their in vitro hydrolysis activities of feed and on the improvement of growth performance in vivo in weanling pigs. Methods Enzyme activities of XMosidases in vitro were evaluated in test tubes and simulation of gastric and small intestinal digestion, respectively, in the presence of NSPase. In vivo study was performed in 108 weaned piglets in a 28-d treatment. Pigs were allotted to one of three dietary treatments with six replicate pens in each treatment. The three treatment groups were as follows: i) Control (basal diet); ii) CE (basal diets+CE); iii) CE-Xmosidases (basal diets+ CE+β-xylosidase at 800 U/kg and β-mannosidase at 40 U/kg). CE was complex enzymes (amylase, protease, xylanase, and mannanase). Results In vitro XMosidases displayed significant activities on hydrolysis of corn and soybean meal in the presence of non-starch polysaccharide degrading enzymes (xylanase and β-mannanase). In vitro simulation of gastric and small intestinal digestion by XMosidases showed XMosidases achieved 67.89%±0.22% of dry matter digestibility and 63.12%±0.21% of energy digestibility at 40°C for 5 hrs. In weanling pigs, additional XMosidases to CE in feed improved average daily gain, feed conversion rate (p<0.05), and apparent total tract digestibility of crude protein (p = 0.01) and dry matter (p = 0.02). XMosidases also altered the gut bacterial diversity and composition by increasing the proportion of beneficial bacteria. Conclusion Addition of a complex enzyme supplementation (contained xylanase, β-mannanase, protease and amylase), XMosidases (β-xylosidase and β-mannosidase) can further improve the growth performance and nutrient digestion of young pigs.
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Affiliation(s)
- Shaoshuai Liu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Chang Ma
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Ling Liu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Dong Ning
- Asiapac Limited Company, Dongguan, Guangdong 523808, China
| | - Yajing Liu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Bing Dong
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
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Huang D, Liu J, Qi Y, Yang K, Xu Y, Feng L. Synergistic hydrolysis of xylan using novel xylanases, β-xylosidases, and an α-L-arabinofuranosidase from Geobacillus thermodenitrificans NG80-2. Appl Microbiol Biotechnol 2017; 101:6023-6037. [PMID: 28616644 DOI: 10.1007/s00253-017-8341-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 03/29/2017] [Accepted: 05/08/2017] [Indexed: 01/01/2023]
Abstract
Lignocellulosic biomass from various types of wood has become a renewable resource for production of biofuels and biobased chemicals. Because xylan is the major component of wood hemicelluloses, highly efficient enzymes to enhance xylan hydrolysis can improve the use of lignocellulosic biomass. In this study, a xylanolytic gene cluster was identified from the crude oil-degrading thermophilic strain Geobacillus thermodenitrificans NG80-2. The enzymes involved in xylan hydrolysis, which include two xylanases (XynA1, XynA2), three β-xylosidases (XynB1, XynB2, XynB3), and one α-L-arabinofuranosidase (AbfA), have many unique features, such as high pH tolerance, high thermostability, and a broad substrate range. The three β-xylosidases were highly resistant to inhibition by product (xylose) accumulation. Moreover, the combination of xylanase, β-xylosidase, and α-L-arabinofuranosidase exhibited the largest synergistic action on xylan degradation (XynA2, XynB1, and AbfA on oat spelt or beechwood xylan; XynA2, XynB3, and AbfA on birchwood xylan). We have demonstrated that the proposed enzymatic cocktail almost completely converts complex xylan to xylose and arabinofuranose and has great potential for use in the conversion of plant biomass into biofuels and biochemicals.
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Affiliation(s)
- Di Huang
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China.
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China.
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, People's Republic of China.
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, People's Republic of China.
| | - Jia Liu
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China
| | - Yanfei Qi
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China
| | - Kexin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China
| | - Yingying Xu
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China
| | - Lu Feng
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Economic-Technological Development Area (TEDA), Nankai University, 23 Hongda Street, Tianjin, 300457, People's Republic of China.
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China.
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, People's Republic of China.
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, People's Republic of China.
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de Figueiredo FC, Carvalho AFA, Brienzo M, Campioni TS, de Oliva-Neto P. Chemical input reduction in the arabinoxylan and lignocellulose alkaline extraction and xylooligosaccharides production. BIORESOURCE TECHNOLOGY 2017; 228:164-170. [PMID: 28063358 DOI: 10.1016/j.biortech.2016.12.097] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/22/2016] [Accepted: 12/23/2016] [Indexed: 05/26/2023]
Abstract
Lignocellulosic material breakdown by hydrolysis is an important step to open new perspectives for bioenergy and special foods production like prebiotic xylooligosaccharides. Improvement of lignocellulose and arabinoxylan alkaline extraction from sugarcane bagasse and enzymatic hydrolysis were performed. Treatments 1 (10% KOH at 70°C), 3 (5% KOH at 121°C) and ZD method (24% KOH at 35°C) showed solid lignocellulose recovery of respectively 75.2%, 74.2% and 73%. A range of 24.8-27% extracted material with high arabinoxylan content (72.1-76.3%) was obtained with these treatments. Treatment 1 and 3 exhibited great KOH reduction in the method reaction, 54.1% and 76.2%, respectively. Likewise, in treatment 3 there was a decrease in ethanol consumption (40.9%) when compared to ZD method. The extracted arabinoxylan showed susceptibility to enzymatic hydrolysis with high solid loading (7%) since Trichoderma reesei xylanases were advantageous for xylose production (54.9%), while Aspergillus fumigatus xylanases achieved better XOS production (27.1%).
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Affiliation(s)
- Franciane Cristina de Figueiredo
- Departament of Biochemistry and Microbiology, Institute of Biosciences, São Paulo State University (UNESP), Avenida 24 A, 1515, ZIP Code 13506-900 Rio Claro, SP, Brazil; Laboratory of Development of Bioprocesses, Bioenergy Research Institute (IPBEN), School of Sciences and Languages, São Paulo State University (UNESP), Avenida Dom Antonio, 2100, ZIP Code 19806-900 Assis, SP, Brazil.
| | - Ana Flavia Azevedo Carvalho
- Laboratory of Development of Bioprocesses, Bioenergy Research Institute (IPBEN), School of Sciences and Languages, São Paulo State University (UNESP), Avenida Dom Antonio, 2100, ZIP Code 19806-900 Assis, SP, Brazil
| | - Michel Brienzo
- Laboratory of Biomass Characterization, Bioenergy Research Institute (IPBEN), São Paulo State University (UNESP), Avenida 24 A, 1515, ZIP Code 13506-900 Rio Claro, SP, Brazil
| | - Tania Sila Campioni
- Laboratory of Development of Bioprocesses, Bioenergy Research Institute (IPBEN), School of Sciences and Languages, São Paulo State University (UNESP), Avenida Dom Antonio, 2100, ZIP Code 19806-900 Assis, SP, Brazil
| | - Pedro de Oliva-Neto
- Laboratory of Development of Bioprocesses, Bioenergy Research Institute (IPBEN), School of Sciences and Languages, São Paulo State University (UNESP), Avenida Dom Antonio, 2100, ZIP Code 19806-900 Assis, SP, Brazil
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Inoue H, Kitao C, Yano S, Sawayama S. Production of β-xylosidase from Trichoderma asperellum KIF125 and its application in efficient hydrolysis of pretreated rice straw with fungal cellulase. World J Microbiol Biotechnol 2016; 32:186. [DOI: 10.1007/s11274-016-2145-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/16/2016] [Indexed: 01/11/2023]
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Grossmann I, Döring C, Jekle M, Becker T, Koehler P. Compositional Changes and Baking Performance of Rye Dough As Affected by Microbial Transglutaminase and Xylanase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:5751-5758. [PMID: 27349134 DOI: 10.1021/acs.jafc.6b01545] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Doughs supplemented with endoxylanase (XYL) and varying amounts of microbial transglutaminase (TG) were analyzed by sequential protein extraction, quantitation of protein fractions and protein types, and determination of water-extractable arabinoxylans. With increasing TG activity, the concentration of prolamins and glutelins decreased and increased, respectively, and the prolamin-to-glutelin ratio strongly declined. The overall amount of extractable protein decreased with increasing TG level showing that cross-linking by TG provided high-molecular-weight protein aggregates. The decrease of the high-molecular-weight arabinoxylan fraction and the concurrent increase of the medium-molecular-weight fraction confirmed the degradation of arabinoxylans by XYL. However, XYL addition did not lead to significant improved cross-linking of rye proteins by TG. Volume and crumb hardness measurements of bread showed increased protein connectivity induced by XYL and TG. Significant positive effects on the final bread quality were especially obtained by XYL addition.
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Affiliation(s)
- Isabel Grossmann
- Deutsche Forschungsanstalt für Lebensmittelchemie, Leibniz Institut , Lise-Meitner-Straße 34, 85354 Freising, Germany
| | - Clemens Döring
- Institute of Brewing and Beverage Technology, Research Group Cereal Process Engineering, Technische Universität München , Weihenstephaner Steig 20, 85354 Freising, Germany
| | - Mario Jekle
- Institute of Brewing and Beverage Technology, Research Group Cereal Process Engineering, Technische Universität München , Weihenstephaner Steig 20, 85354 Freising, Germany
| | - Thomas Becker
- Institute of Brewing and Beverage Technology, Research Group Cereal Process Engineering, Technische Universität München , Weihenstephaner Steig 20, 85354 Freising, Germany
| | - Peter Koehler
- Deutsche Forschungsanstalt für Lebensmittelchemie, Leibniz Institut , Lise-Meitner-Straße 34, 85354 Freising, Germany
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Elzobair KA, Stromberger ME, Ippolito JA. Stabilizing effect of biochar on soil extracellular enzymes after a denaturing stress. CHEMOSPHERE 2016; 142:114-119. [PMID: 25840745 DOI: 10.1016/j.chemosphere.2015.03.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 03/02/2015] [Accepted: 03/03/2015] [Indexed: 06/04/2023]
Abstract
Stabilizing extracellular enzymes may maintain enzymatic activity while protecting enzymes from proteolysis and denaturation. A study determined whether a fast pyrolysis hardwood biochar (CQuest™) would reduce evaporative losses, subsequently stabilizing soil extracellular enzymes and prohibiting potential enzymatic activity loss following a denaturing stress (microwaving). Soil was incubated in the presence of biochar (0%, 1%, 2%, 5%, or 10% by wt.) for 36 days and then exposed to microwave energies (0, 400, 800, 1600, or 3200 J g(-1) soil). Soil enzymes (β-glucosidase, β-d-cellobiosidase, N-acetyl-β-glucosaminidase, phosphatase, leucine aminopeptidase, β-xylosidase) were analyzed by fluorescence-based assays. Biochar amendment reduced leucine aminopeptidase and β-xylosidase potential activity after the incubation period and prior to stress exposure. The 10% biochar rate reduced soil water loss at the lowest stress level (400 J microwave energy g(-1) soil). Enzyme stabilization was demonstrated for β-xylosidase; intermediate biochar application rates prevented a complete loss of this enzyme's potential activity after soil was exposed to 400 (1% biochar treatment) or 1600 (5% biochar treatment) J microwave energy g(-1) soil. Remaining enzyme potential activities were not affected by biochar, and activities decreased with increasing stress levels. We concluded that biochar has the potential to reduce evaporative soil water losses and stabilize certain extracellular enzymes where activity is maintained after a denaturing stress; this effect was biochar rate and enzyme dependent. While biochar may reduce the potential activity of certain soil extracellular enzymes, this phenomenon was not universal as the majority of enzymes assayed in this study were unaffected by exposure to biochar.
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Affiliation(s)
- Khalid A Elzobair
- Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523-1170, United States
| | - Mary E Stromberger
- Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523-1170, United States.
| | - James A Ippolito
- USDA-ARS Northwest Irrigation and Soils Research Laboratory, Kimberly, ID 83341, United States
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Affiliation(s)
- Shiping Deng
- Oklahoma State University; Department of Plant and Soil Sciences; 368 Agricultural Hall Stillwater OK 74078
| | - Inna Popova
- Oklahoma State University; Department of Plant and Soil Sciences; 368 Agricultural Hall Stillwater OK 74078
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Novel pH-Stable Glycoside Hydrolase Family 3 β-Xylosidase from Talaromyces amestolkiae: an Enzyme Displaying Regioselective Transxylosylation. Appl Environ Microbiol 2015; 81:6380-92. [PMID: 26150469 DOI: 10.1128/aem.01744-15] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/01/2015] [Indexed: 11/20/2022] Open
Abstract
This paper reports on a novel β-xylosidase from the hemicellulolytic fungus Talaromyces amestolkiae. The expression of this enzyme, called BxTW1, could be induced by beechwood xylan and was purified as a glycoprotein from culture supernatants. We characterized the gene encoding this enzyme as an intronless gene belonging to the glycoside hydrolase gene family 3 (GH3). BxTW1 exhibited transxylosylation activity in a regioselective way. This feature would allow the synthesis of oligosaccharides or other compounds not available from natural sources, such as alkyl glycosides displaying antimicrobial or surfactant properties. Regioselective transxylosylation, an uncommon combination, makes the synthesis reproducible, which is desirable for its potential industrial application. BxTW1 showed high pH stability and Cu(2+) tolerance. The enzyme displayed a pI of 7.6, a molecular mass around 200 kDa in its active dimeric form, and Km and Vmax values of 0.17 mM and 52.0 U/mg, respectively, using commercial p-nitrophenyl-β-d-xylopyranoside as the substrate. The catalytic efficiencies for the hydrolysis of xylooligosaccharides were remarkably high, making it suitable for different applications in food and bioenergy industries.
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Wang M, Lai GL, Nie Y, Geng S, Liu L, Zhu B, Shi Z, Wu XL. Synergistic function of four novel thermostable glycoside hydrolases from a long-term enriched thermophilic methanogenic digester. Front Microbiol 2015; 6:509. [PMID: 26052323 PMCID: PMC4441150 DOI: 10.3389/fmicb.2015.00509] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 05/08/2015] [Indexed: 12/25/2022] Open
Abstract
In biofuel production from lignocellulose, low thermostability and product inhibition strongly restrict the enzyme activities and production process. Application of multiple thermostable glycoside hydrolases, forming an enzyme "cocktail", can result in a synergistic action and therefore improve production efficiency and reduce operational costs. Therefore, increasing enzyme thermostabilities and compatibility are important for the biofuel industry. In this study, we reported the screening, cloning and biochemical characterization of four novel thermostable lignocellulose hydrolases from a metagenomic library of a long-term dry thermophilic methanogenic digester community, which were highly compatible with optimal conditions and specific activities. The optimal temperatures of the four enzymes, β-xylosidase, xylanase, β-glucosidase, and cellulase ranged from 60 to 75°C, and over 80% residual activities were observed after 2 h incubation at 50°C. Mixtures of these hydrolases retained high residual synergistic activities after incubation with cellulose, xylan, and steam-exploded corncob at 50°C for 72 h. In addition, about 55% dry weight of steam-exploded corncob was hydrolyzed to glucose and xylose by the synergistic action of the four enzymes at 50°C for 48 h. This work suggested that since different enzymes from a same ecosystem could be more compatible, screening enzymes from a long-term enriching community could be a favorable strategy.
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Affiliation(s)
- Meng Wang
- School of Biotechnology, Jiangnan University Wuxi, China ; Department of Energy and Resources Engineering, College of Engineering, Peking University Beijing, China
| | - Guo-Li Lai
- Department of Energy and Resources Engineering, College of Engineering, Peking University Beijing, China ; Institute of Engineering (Baotou), College of Engineering, Peking University Baotou, China
| | - Yong Nie
- Department of Energy and Resources Engineering, College of Engineering, Peking University Beijing, China ; Institute of Engineering (Baotou), College of Engineering, Peking University Baotou, China
| | - Shuang Geng
- Department of Energy and Resources Engineering, College of Engineering, Peking University Beijing, China
| | - Liming Liu
- School of Biotechnology, Jiangnan University Wuxi, China
| | - Baoli Zhu
- Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Zhongping Shi
- School of Biotechnology, Jiangnan University Wuxi, China
| | - Xiao-Lei Wu
- Department of Energy and Resources Engineering, College of Engineering, Peking University Beijing, China ; Institute of Engineering (Baotou), College of Engineering, Peking University Baotou, China
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Chai Y, Jin Y, Du J, Li J, Zhang K. Partial characterization ofβ-d-xylosidase from wheat malts. JOURNAL OF THE INSTITUTE OF BREWING 2015. [DOI: 10.1002/jib.228] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yanan Chai
- College of Food Science and Engineering; Shandong Agricultural University; Tai'an 271018 People's Republic of China
| | - Yuhong Jin
- College of Food Science and Engineering; Shandong Agricultural University; Tai'an 271018 People's Republic of China
| | - Jinhua Du
- College of Food Science and Engineering; Shandong Agricultural University; Tai'an 271018 People's Republic of China
| | - Jia Li
- College of Food Science and Engineering; Shandong Agricultural University; Tai'an 271018 People's Republic of China
| | - Kaili Zhang
- Shandong Taishan Beer Co. Ltd; Tai’ an 271000 People's Republic of China
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Impact of Xylan on Synergistic Effects of Xylanases and Cellulases in Enzymatic Hydrolysis of Lignocelluloses. Appl Biochem Biotechnol 2014; 174:1393-1402. [DOI: 10.1007/s12010-014-1140-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/01/2014] [Indexed: 10/24/2022]
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17
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Ethanol Production from Xylo-oligosaccharides by Xylose-FermentingSaccharomyces cerevisiaeExpressing β-Xylosidase. Biosci Biotechnol Biochem 2014; 75:1140-6. [DOI: 10.1271/bbb.110043] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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18
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Cai P, Gu R, Wang B, Li J, Wan L, Tian C, Ma Y. Evidence of a critical role for cellodextrin transporte 2 (CDT-2) in both cellulose and hemicellulose degradation and utilization in Neurospora crassa. PLoS One 2014; 9:e89330. [PMID: 24586693 PMCID: PMC3930720 DOI: 10.1371/journal.pone.0089330] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 01/18/2014] [Indexed: 11/19/2022] Open
Abstract
CDT-1 and CDT-2 are two cellodextrin transporters discovered in the filamentous fungus Neurospora crassa. Previous studies focused on characterizing the role of these transporters in only a few conditions, including cellulose degradation, and the function of these two transporters is not yet completely understood. In this study, we show that deletion of cdt-2, but not cdt-1, results in growth defects not only on Avicel but also on xylan. cdt-2 can be highly induced by xylan, and this mutant has a xylodextrin consumption defect. Transcriptomic analysis of the cdt-2 deletion strain on Avicel and xylan showed that major cellulase and hemicellulase genes were significantly down-regulated in the cdt-2 deletion strain and artificial over expression of cdt-2 in N. crassa increased cellulase and hemicellulase production. Together, these data clearly show that CDT-2 plays a critical role in hemicellulose sensing and utilization. This is the first time a sugar transporter has been assigned a function in the hemicellulose degradation pathway. Furthermore, we found that the transcription factor XLR-1 is the major regulator of cdt-2, while cdt-1 is primarily regulated by CLR-1. These results deepen our understanding of the functions of both cellodextrin transporters, particularly for CDT-2. Our study also provides novel insight into the mechanisms for hemicellulose sensing and utilization in N. crassa, and may be applicable to other cellulolytic filamentous fungi.
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Affiliation(s)
- Pengli Cai
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Ruimeng Gu
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Bang Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jingen Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Li Wan
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yanhe Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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Isikhuemhen OS, Mikiashvili NA, Senwo ZN, Ohimain EI. Biodegradation and Sugar Release from Canola Plant Biomass by Selected White Rot Fungi. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/abc.2014.46045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Salamanca-Cardona L, Ashe CS, Stipanovic AJ, Nomura CT. Enhanced production of polyhydroxyalkanoates (PHAs) from beechwood xylan by recombinant Escherichia coli. Appl Microbiol Biotechnol 2013; 98:831-42. [DOI: 10.1007/s00253-013-5398-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 11/06/2013] [Accepted: 11/09/2013] [Indexed: 11/29/2022]
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Lo LC, Chu CY, Lin FA, Pan YR, Li YK, Lin JJ. Synthesis of Activity Probes for β-Xylosidase. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200600063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Qi H, Bai F, Liu A. Purification and characteristics of xyloglucanase and five other cellulolytic enzymes from Trichoderma reesei QM9414. BIOCHEMISTRY (MOSCOW) 2013; 78:424-30. [DOI: 10.1134/s0006297913040123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Enzyme kinetics and identification of the rate-limiting step of enzymatic arabinoxylan degradation. Biochem Eng J 2012. [DOI: 10.1016/j.bej.2012.08.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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24
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Makaravicius T, Basinskiene L, Juodeikiene G, van Gool MP, Schols HA. Production of oligosaccharides from extruded wheat and rye biomass using enzymatic treatment. Catal Today 2012. [DOI: 10.1016/j.cattod.2012.02.053] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Treatments with Xylanase at High (90 %) and Low (40 %) Water Content Have Different Impacts on Physicochemical Properties of Wheat Bran. FOOD BIOPROCESS TECH 2012. [DOI: 10.1007/s11947-012-0967-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Romero A, Mateo J, Maicas S. Characterization of an ethanol-tolerant 1,4-β-xylosidase produced byPichia membranifaciens. Lett Appl Microbiol 2012; 55:354-61. [DOI: 10.1111/j.1472-765x.2012.03297.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Srikrishnan S, Chen W, Da Silva NA. Functional assembly and characterization of a modular xylanosome for hemicellulose hydrolysis in yeast. Biotechnol Bioeng 2012; 110:275-85. [DOI: 10.1002/bit.24609] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 06/27/2012] [Accepted: 07/02/2012] [Indexed: 11/07/2022]
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Michelin M, Peixoto-Nogueira SC, Silva TM, Jorge JA, Terenzi HF, Teixeira JA, Polizeli MDLTM. A novel xylan degrading β-D-xylosidase: purification and biochemical characterization. World J Microbiol Biotechnol 2012; 28:3179-86. [PMID: 22828792 DOI: 10.1007/s11274-012-1128-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 07/06/2012] [Indexed: 11/26/2022]
Abstract
Aspergillus ochraceus, a thermotolerant fungus isolated in Brazil from decomposing materials, produced an extracellular β-xylosidase that was purified using DEAE-cellulose ion exchange chromatography, Sephadex G-100 and Biogel P-60 gel filtration. β-xylosidase is a glycoprotein (39 % carbohydrate content) and has a molecular mass of 137 kDa by SDS-PAGE, with optimal temperature and pH at 70 °C and 3.0-5.5, respectively. β-xylosidase was stable in acidic pH (3.0-6.0) and 70 °C for 1 h. The enzyme was activated by 5 mM MnCl₂ (28 %) and MgCl₂ (20 %) salts. The β-xylosidase produced by A. ochraceus preferentially hydrolyzed p-nitrophenyl-β-D-xylopyranoside, exhibiting apparent K(m) and V(max) values of 0.66 mM and 39 U (mg protein)⁻¹ respectively, and to a lesser extent p-nitrophenyl-β-D-glucopyranoside. The enzyme was able to hydrolyze xylan from different sources, suggesting a novel β-D-xylosidase that degrades xylan. HPLC analysis revealed xylans of different compositions which allowed explaining the differences in specificity observed by β-xylosidase. TLC confirmed the capacity of the enzyme in hydrolyzing xylan and larger xylo-oligosaccharides, as xylopentaose.
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Affiliation(s)
- Michele Michelin
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP 14040-901, Brazil
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Niemi P, Faulds CB, Sibakov J, Holopainen U, Poutanen K, Buchert J. Effect of a milling pre-treatment on the enzymatic hydrolysis of carbohydrates in brewer's spent grain. BIORESOURCE TECHNOLOGY 2012; 116:155-160. [PMID: 22609670 DOI: 10.1016/j.biortech.2012.04.043] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/11/2012] [Accepted: 04/13/2012] [Indexed: 06/01/2023]
Abstract
Millions of tonnes of brewer's spent grain (BSG) are annually produced worldwide as a by-product of the brewing industry. BSG has the potential to be a valuable source of food, chemicals and energy if cost-efficient fractionation methods can be developed. A 2-fold improvement in carbohydrate solubilisation could be achieved through the introduction of a milling step prior to enzymatic hydrolysis. Course and fine milled fractions were characterized by particle size distribution and light microscopy. Fine milling decreased particle size down to the micron level and this in turn improved the carbohydrate solubility yield by a multi-enzyme mixture from 23% up to 45%. Carbohydrate solubilisation could be further increased through the supplementation of this enzyme preparation with additional cellulases. The physical degradation caused by the milling also liberated soluble carbohydrates without the requirement of any enzymatic treatment.
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Affiliation(s)
- Piritta Niemi
- VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
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Sun J, Shao Z, Zhao H, Nair N, Wen F, Xu JH, Zhao H. Cloning and characterization of a panel of constitutive promoters for applications in pathway engineering in Saccharomyces cerevisiae. Biotechnol Bioeng 2012; 109:2082-92. [PMID: 22383307 DOI: 10.1002/bit.24481] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 02/08/2012] [Accepted: 02/13/2012] [Indexed: 11/09/2022]
Abstract
Saccharomyces cerevisiae is an important platform organism for synthesis of chemicals and fuels. However, the promoters used in most pathway engineering studies in S. cerevisiae have not been characterized and compared in parallel under multiple conditions that are routinely operated in laboratory and the number of known promoters is rather limited for the construction of large biochemical pathways. Here a total of 14 constitutive promoters from S. cerevisiae were cloned and characterized using a green fluorescent protein (GFP) as a reporter in a 2 µ vector pRS426, under varying glucose and oxygen concentrations. The strengths of these promoters varied no more than sixfold in the mean fluorescence intensity of GFP, with promoter TEF1p being the strongest and promoter PGI1p the weakest. As an example of application for these promoters in metabolic engineering, the genes involved in xylan degradation and zeaxanthin biosynthesis were subsequently cloned under the control of promoters with medium to high strength and assembled into a single pathway. The corresponding construct was transformed to a S. cerevisiae strain integrated with a D-xylose utilizing pathway. The resulting strain produced zeaxanthin with a titer of 0.74 ± 0.02 mg/L directly from birchwood xylan.
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Affiliation(s)
- Jie Sun
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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The tropical white rot fungus, Lentinus squarrosulus Mont.: lignocellulolytic enzymes activities and sugar release from cornstalks under solid state fermentation. World J Microbiol Biotechnol 2012; 28:1961-6. [PMID: 22806017 DOI: 10.1007/s11274-011-0998-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 12/29/2011] [Indexed: 10/14/2022]
Abstract
Lentinus squarrosulus Mont., a high temperature tolerant white rot fungus that is found across sub-Saharan Africa and many parts of Asia, is attracting attention due to its rapid mycelia growth and potential for use in food and biodegradation. A solid state fermentation (SSF) experiment with L. squarrosulus (strain MBFBL 201) on cornstalks was conducted. The study evaluated lignocellulolytic enzymes activity, loss of organic matter (LOM), exopolysaccharide content, and the release of water soluble sugars from degraded substrate. The results showed that L. squarrosulus was able to degrade cornstalks significantly, with 58.8% LOM after 30 days of SSF. Maximum lignocellulolytic enzyme activities were obtained on day 6 of cultivation: laccase = 154.5 U/L, MnP = 13 U/L, peroxidase = 27.4 U/L, CMCase = 6.0 U/mL and xylanase = 14.5 U/mL. L. squarrosulus is a good producer of exopolysaccharides (3.0-5.13 mg/mL). Glucose and galactose were the most abundant sugars detected in the substrate during SSF, while fructose, xylose and trehalose, although detected on day zero of the experiment, were absent in treated substrates. The preference for hemicellulose over cellulose, combined with the high temperature tolerance and the very fast growth rate characteristics of L. squarrosulus could make it an ideal candidate for application in industrial pretreatment and biodelignification of lignocellulosic biomass.
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Jun H, Kieselbach T, Jönsson LJ. Enzyme production by filamentous fungi: analysis of the secretome of Trichoderma reesei grown on unconventional carbon source. Microb Cell Fact 2011; 10:68. [PMID: 21861877 PMCID: PMC3179704 DOI: 10.1186/1475-2859-10-68] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 08/23/2011] [Indexed: 12/17/2022] Open
Abstract
Background Spent hydrolysates from bioethanolic fermentation processes based on agricultural residues have potential as an abundant and inexpensive source of pentose sugars and acids that could serve as nutrients for industrial enzyme-producing microorganisms, especially filamentous fungi. However, the enzyme mixtures produced in such media are poorly defined. In this study, the secretome of Trichoderma reesei Rut C-30 grown either on a spent hydrolysate model medium (SHMM) or on a lactose-based standard medium (LBSM) was explored using proteomics. Results Our results show that both the SHMM and LBSM serve as excellent growth media for T. reesei Rut C-30. In total, 52 protein spots on 2-D gels were identified by using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and electrospray ionization liquid chromatography tandem mass spectrometry (ESI-LC MS/MS). As expected, a considerable number of the identified proteins were related to the degradation of lignocellulosic biomass. The enzyme production profiles in the two media were similar, but β-glucosidase and β-galactosidase were only produced in LBSM. The main cellobiohydrolases (Cel7A/Cel6A) and endoglucanases (Cel7B/Cel5A) were identified in both media and the cellobiohydrolases, i.e. Cel7A and Cel6A, were the most abundant cellulolytic enzymes. Moreover, both media can also serve as a potent inducer of xylanolytic enzymes. Several key enzymes involved in sugar assimilation and regulation of cellulase formation were identified, and were found to be differentially expressed in the two growth media. Conclusions This study not only provides a catalogue of the prevalent proteins secreted by T. reesei in the two media, but the results also suggest that production of hydrolytic enzymes using unconventional carbon sources, such as components in spent hydrolysates, deserves further attention in the future.
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Affiliation(s)
- He Jun
- Department of Chemistry, Umeå University, Umeå, Sweden.
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Knob A, Carmona EC. Purification and properties of an acid β-xylosidase from Penicillium sclerotiorum. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0282-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Zhang J, Siika-aho M, Puranen T, Tang M, Tenkanen M, Viikari L. Thermostable recombinant xylanases from Nonomuraea flexuosa and Thermoascus aurantiacus show distinct properties in the hydrolysis of xylans and pretreated wheat straw. BIOTECHNOLOGY FOR BIOFUELS 2011; 4:12. [PMID: 21592333 PMCID: PMC3114720 DOI: 10.1186/1754-6834-4-12] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 05/18/2011] [Indexed: 05/06/2023]
Abstract
BACKGROUND In the hydrolysis of lignocellulosic materials, thermostable enzymes decrease the amount of enzyme needed due to higher specific activity and elongate the hydrolysis time due to improved stability. For cost-efficient use of enzymes in large-scale industrial applications, high-level expression of enzymes in recombinant hosts is usually a prerequisite. The main aim of the present study was to compare the biochemical and hydrolytic properties of two thermostable recombinant glycosyl hydrolase families 10 and 11 (GH10 and GH11, respectively) xylanases with respect to their potential application in the hydrolysis of lignocellulosic substrates. RESULTS The xylanases from Nonomuraea flexuosa (Nf Xyn11A) and from Thermoascus aurantiacus (Ta Xyn10A) were purified by heat treatment and gel permeation chromatography. Ta Xyn10A exhibited higher hydrolytic efficiency than Nf Xyn11A toward birchwood glucuronoxylan, insoluble oat spelt arabinoxylan and hydrothermally pretreated wheat straw, and it produced more reducing sugars. Oligosaccharides from xylobiose to xylopentaose as well as higher degree of polymerization (DP) xylooligosaccharides (XOSs), but not xylose, were released during the initial hydrolysis of xylans by Nf Xyn11A, indicating its potential for the production of XOS. The mode of action of Nf Xyn11A and Ta Xyn10A on glucuronoxylan and arabinoxylan showed typical production patterns of endoxylanases belonging to GH11 and GH10, respectively. CONCLUSIONS Because of its high catalytic activity and good thermostability, T. aurantiacus xylanase shows great potential for applications aimed at total hydrolysis of lignocellulosic materials for platform sugars, whereas N. flexuosa xylanase shows more significant potential for the production of XOSs.
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Affiliation(s)
- Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Matti Siika-aho
- VTT Technical Research Centre of Finland, P.O. Box 1000, FIN-02044 Espoo, Finland
| | - Terhi Puranen
- Roal Oy, Tykkimäentie 15, FIN-05200, Rajamäki, Finland
| | - Ming Tang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Maija Tenkanen
- Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Liisa Viikari
- Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
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Dilokpimol A, Nakai H, Gotfredsen CH, Appeldoorn M, Baumann MJ, Nakai N, Schols HA, Hachem MA, Svensson B. Enzymatic synthesis of β-xylosyl-oligosaccharides by transxylosylation using two β-xylosidases of glycoside hydrolase family 3 from Aspergillus nidulans FGSC A4. Carbohydr Res 2011; 346:421-9. [DOI: 10.1016/j.carres.2010.12.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 12/10/2010] [Accepted: 12/11/2010] [Indexed: 11/25/2022]
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Characterization of a novel beta-xylosidase, XylC, from Thermoanaerobacterium saccharolyticum JW/SL-YS485. Appl Environ Microbiol 2010; 77:719-26. [PMID: 21131522 DOI: 10.1128/aem.01511-10] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The 1,914-bp open reading frame of xylC from Thermoanaerobacterium saccharolyticum JW/SL-YS485 encodes a calculated 73-kDa β-xylosidase, XylC, different from any glycosyl hydrolase in the database and representing a novel glycohydrolase family. Hydrolysis occurred under retention of the anomeric configuration, and transglycosylation occurred in the presence of alcohols as acceptors. With the use of vector pHsh, expression of XylC, the third β-xylosidase in this bacterium, increased approximately 4-fold when a loop within the translational initiation region in the mRNA was removed by site-directed mutagenesis. The increased expression of xylC(m) is due to removal of a stem-loop structure without a change of the amino acid sequence of the heterologously expressed enzyme (XylC(rec)). When gel filtration was applied, purified XylC had molecular masses of 210 kDa and 265 kDa using native gradient gel electrophoresis. The protein consisted of 78-kDa subunits based on SDS gel electrophoresis and contained 6% carbohydrates. XylC and XylC(rec) exhibited maximum activity at 65°C and pH(65°C) 6.0, a 1-h half-life at 67°C, a K(m) for p-nitrophenyl-β-D-xyloside of 28 mM, and a V(max) of 276 U/mg and retained 70% activity in the presence of 200 mM xylose, suggesting potential for industrial applications.
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Sipponen MH, Pastinen OA, Strengell R, Hyötyläinen JMI, Heiskanen IT, Laakso S. Increased Water Resistance of CTMP Fibers by Oat (Avena sativa L.) Husk Lignin. Biomacromolecules 2010; 11:3511-8. [DOI: 10.1021/bm101007u] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mika H. Sipponen
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
| | - Ossi A. Pastinen
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
| | - Reetta Strengell
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
| | - Juha M. I. Hyötyläinen
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
| | - Isto T. Heiskanen
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
| | - Simo Laakso
- Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland, Kemira Oyj, Espoo R&D Center, Espoo, Finland, and Stora Enso Research Center, Imatra, Finland
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Wang R, Xue Y, Wu X, Song X, Peng J. Enhancement of engineered trifunctional enzyme by optimizing linker peptides for degradation of agricultural by-products. Enzyme Microb Technol 2010. [DOI: 10.1016/j.enzmictec.2010.07.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Ohta K, Fujimoto H, Fujii S, Wakiyama M. Cell-associated β-xylosidase from Aureobasidium pullulans ATCC 20524: Purification, properties, and characterization of the encoding gene. J Biosci Bioeng 2010; 110:152-7. [DOI: 10.1016/j.jbiosc.2010.02.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 01/08/2010] [Accepted: 02/09/2010] [Indexed: 10/19/2022]
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Møller MF, Kjeldsen KU, Ingvorsen K. Marinimicrobium haloxylanilyticum sp. nov., a new moderately halophilic, polysaccharide-degrading bacterium isolated from Great Salt Lake, Utah. Antonie van Leeuwenhoek 2010; 98:553-65. [PMID: 20574646 DOI: 10.1007/s10482-010-9472-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 06/09/2010] [Indexed: 11/29/2022]
Abstract
A new moderately halophilic, strictly aerobic, Gram-negative bacterium, strain SX15(T), was isolated from hypersaline surface sediment of the southern arm of Great Salt Lake (Utah, USA). The strain grew on a number of carbohydrates and carbohydrate polymers such as xylan, starch, carboxymethyl cellulose and galactomannan. The strain grew at salinities ranging from 2 to 22% NaCl (w/v). Optimal growth occurred in the presence of 7-11% NaCl (w/v) at a temperature of 35°C and a pH of 6.7-8.2. Major whole-cell fatty acids were C16:0 (30.5%), C18:0 (14.8%), C18:1ω7c (13.1%) and C12:0 (7.8%). The G+C content of the DNA was 60 ± 0.5 mol%. By 16S rRNA gene sequence analysis, strain SX15(T) was shown to be affiliated to members of the gammaproteobacterial genus Marinimicrobium with pair wise identity values of 92.9-94.6%. The pheno- and genotypic properties suggest that strain SX15(T) represents a novel species of the genus Marinimicrobium for which the name Marinimicrobium haloxylanilyticum is proposed. The type strain is SX15(T) (= DSM 23100(T) = CCUG 59572(T)).
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Abdeshahia P, Samat N, Wan Yusoff W. Production of β-Xylosidase by Aspergillus niger FTCC 5003 Using Palm Kernel Cake in a Packed-Bed Bioreactor. ACTA ACUST UNITED AC 2010. [DOI: 10.3923/jas.2010.419.424] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Characterisation of specific activities and hydrolytic properties of cell-wall-degrading enzymes produced by Trichoderma reesei Rut C30 on different carbon sources. Appl Biochem Biotechnol 2009; 161:347-64. [PMID: 19898963 DOI: 10.1007/s12010-009-8824-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 10/13/2009] [Indexed: 10/20/2022]
Abstract
Conversion of lignocellulosic substrates is limited by several factors, in terms of both the enzymes and the substrates. Better understanding of the hydrolysis mechanisms and the factors determining their performance is crucial for commercial lignocelluloses-based processes. Enzymes produced on various carbon sources (Solka Floc 200, lactose and steam-pre-treated corn stover) by Trichoderma reesei Rut C30 were characterised by their enzyme profile and hydrolytic performance. The results showed that there was a clear correlation between the secreted amount of xylanase and mannanase enzymes and that their production was induced by the presence of xylan in the carbon source. Co-secretion of alpha-arabinosidase and alpha-galactosidase was also observed. Secretion of beta-glucosidase was found to be clearly dependent on the composition of the carbon source, and in the case of lactose, 2-fold higher specific activity was observed compared to Solka Floc and steam-pre-treated corn stover. Hydrolysis experiments showed a clear connection between glucan and xylan conversion and highlighted the importance of beta-glucosidase and xylanase activities. When hydrolysis was performed using additional purified beta-glucosidase and xylanase, the addition of beta-glucosidase was found to significantly improve both the xylan and glucan conversion.
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Knob A, Terrasan CRF, Carmona EC. β-Xylosidases from filamentous fungi: an overview. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0190-4] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Isikhuemhen OS, Mikiashvilli NA. Lignocellulolytic enzyme activity, substrate utilization, and mushroom yield by Pleurotus ostreatus cultivated on substrate containing anaerobic digester solids. J Ind Microbiol Biotechnol 2009; 36:1353-62. [DOI: 10.1007/s10295-009-0620-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2008] [Accepted: 06/30/2009] [Indexed: 10/20/2022]
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Dueñas MJ, Estrada P. Immobilization of β-Xylosidase fromTrichoderma ReeseiQM 9414 on Nylon Powder. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.3109/10242429909015228] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kovacs K, Macrelli S, Szakacs G, Zacchi G. Enzymatic hydrolysis of steam-pretreated lignocellulosic materials with Trichoderma atroviride enzymes produced in-house. BIOTECHNOLOGY FOR BIOFUELS 2009; 2:14. [PMID: 19580644 PMCID: PMC2717933 DOI: 10.1186/1754-6834-2-14] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Accepted: 07/06/2009] [Indexed: 05/19/2023]
Abstract
BACKGROUND Improvement of the process of cellulase production and development of more efficient lignocellulose-degrading enzymes are necessary in order to reduce the cost of enzymes required in the biomass-to-bioethanol process. RESULTS Lignocellulolytic enzyme complexes were produced by the mutant Trichoderma atroviride TUB F-1663 on three different steam-pretreated lignocellulosic substrates, namely spruce, wheat straw and sugarcane bagasse. Filter paper activities of the enzymes produced on the three materials were very similar, while beta-glucosidase and hemicellulase activities were more dependent on the nature of the substrate. Hydrolysis of the enzyme preparations investigated produced similar glucose yields. However, the enzymes produced in-house proved to degrade the xylan and the xylose oligomers less efficiently than a commercial mixture of cellulase and beta-glucosidase. Furthermore, accumulation of xylose oligomers was observed when the TUB F-1663 supernatants were applied to xylan-containing substrates, probably due to the low beta-xylosidase activity of the enzymes. The efficiency of the enzymes produced in-house was enhanced by supplementation with extra commercial beta-glucosidase and beta-xylosidase. When the hydrolytic capacities of various mixtures of a commercial cellulase and a T. atroviride supernatant produced in the lab were investigated at the same enzyme loading, the glucose yield appeared to be correlated with the beta-glucosidase activity, while the xylose yield seemed to be correlated with the beta-xylosidase level in the mixtures. CONCLUSION Enzyme supernatants produced by the mutant T. atroviride TUB F-1663 on various pretreated lignocellulosic substrates have good filter paper activity values combined with high levels of beta-glucosidase activities, leading to cellulose conversion in the enzymatic hydrolysis that is as efficient as with a commercial cellulase mixture. On the other hand, in order to achieve good xylan conversion, the supernatants produced by the mutant have to be supplemented with additional beta-xylosidase activity.
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Affiliation(s)
- Krisztina Kovacs
- Department of Chemical Engineering, Lund University, Lund, Sweden
- Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, Budapest, Hungary
| | - Stefano Macrelli
- Department of Chemical Engineering, Lund University, Lund, Sweden
| | - George Szakacs
- Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, Budapest, Hungary
| | - Guido Zacchi
- Department of Chemical Engineering, Lund University, Lund, Sweden
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Xue Y, Peng J, Wang R, Song X. Construction of the trifunctional enzyme associating the Thermoanaerobacter ethanolicus xylosidase-arabinosidase with the Thermomyces lanuginosus xylanase for degradation of arabinoxylan. Enzyme Microb Technol 2009. [DOI: 10.1016/j.enzmictec.2009.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Application of solid waste from anaerobic digestion of poultry litter in Agrocybe aegerita cultivation: mushroom production, lignocellulolytic enzymes activity and substrate utilization. Biodegradation 2008; 20:351-61. [PMID: 18982415 DOI: 10.1007/s10532-008-9226-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 10/20/2008] [Indexed: 10/21/2022]
Abstract
The degradation and utilization of solid waste (SW) from anaerobic digestion of poultry litter by Agrocybe aegerita was evaluated through mushroom production, loss of organic matter (LOM), lignocellulolytic enzymes activity, lignocellulose degradation and mushroom nutrients content. Among the substrate combinations (SCs) tested, substrates composed of 10-20% SW, 70-80% wheat straw and 10% millet was found to produce the highest mushroom yield (770.5 and 642.9 g per 1.5 kg of substrate). LOM in all SCs tested varied between 8.8 and 48.2%. A. aegerita appears to degrade macromolecule components (0.6-21.8% lignin, 33.1-55.2% cellulose and 14-53.9% hemicellulose) during cultivation on the different SCs. Among the seven extracellular enzymes monitored, laccase, peroxidase and CMCase activities were higher before fruiting; while xylanase showed higher activities after fruiting. A source of carbohydrates (e.g., millet) in the substrate is needed in order to obtain yield and biological efficiency comparable to other commercially cultivated exotic mushrooms.
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Novel family of carbohydrate esterases, based on identification of the Hypocrea jecorina acetyl esterase gene. Appl Environ Microbiol 2008; 74:7482-9. [PMID: 18978092 DOI: 10.1128/aem.00807-08] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plant cell walls have been shown to contain acetyl groups in hemicelluloses and pectin. The gene aes1, encoding the acetyl esterase (Aes1) of Hypocrea jecorina, was identified by amino-terminal sequencing, peptide mass spectrometry, and genomic sequence analyses. The coded polypeptide had 348 amino acid residues with the first 19 serving as a secretion signal peptide. The calculated molecular mass and isoelectric point of the secreted enzyme were 37,088 Da and pH 5.89, respectively. No significant homology was found between the predicated Aes1 and carbohydrate esterases of known families, but putative aes1 orthologs were found in genomes of many fungi and bacteria that produce cell wall-degrading enzymes. The aes1 transcript levels were high when the fungal cells were induced with sophorose, cellulose, oat spelt xylan, lactose, and arabinose. The recombinant Aes1 produced by H. jecorina transformed with aes1 under the cellobiohydrolase I promoter displayed properties similar to those reported for the native enzyme. The enzyme hydrolyzed acetate ester bond specifically. Using 4-nitrophenyl acetate as substrate, the activity of the recombinant enzyme was enhanced by D-xylose, D-glucose, cellobiose, D-galactose, and xylooligosaccharides but not by arabinose, mannose, or lactose. With the use of 4-nitrophenyl-beta-D-xylopyranoside monoacetate as substrate in a beta-xylosidase-coupled assay, Aes1 hydrolyzed positions 3 and 4 with the same efficiency while the H. jecorina acetylxylan esterase 1 exclusively deacetylated the position 2 acetyl group. Aes1 was capable of transacetylating methylxyloside in aqueous solution. The data presented demonstrate that Aes1 and other homologous microbial proteins may represent a new family of esterases for lignocellulose biodegradation.
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Wakiyama M, Yoshihara K, Hayashi S, Ohta K. Purification and Properties of an Extracellular β-Xylosidase from Aspergillus japonicus and Sequence Analysis of the Encoding Gene. J Biosci Bioeng 2008; 106:398-404. [DOI: 10.1263/jbb.106.398] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Accepted: 07/11/2008] [Indexed: 11/17/2022]
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