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du Preez LL, van der Walt E, Valverde A, Rothmann C, Neser FWC, Cason ED. A metagenomic survey of the fecal microbiome of the African savanna elephant (Loxodonta africana). Anim Genet 2024; 55:621-643. [PMID: 38923598 DOI: 10.1111/age.13458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 06/06/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024]
Abstract
The African savanna elephant (Loxodonta africana) is the largest terrestrial animal on Earth and is found primarily in Southern and Eastern Africa. It is a hindgut, colonic fermenter and subsists on a diet of raw plant materials found in its grazing area. In this study the bacterial, archaeal and fungal populations of seven African savanna elephant fecal metagenomes were first characterized using amplicon sequencing. On the genus level it was observed that the p-1088-a5 gut group in the bacteriome, Methanocorpusulum and Methanobrevibacter in the archaeome and Alternaria, Aurobasidium, Didymella and Preussia in the mycome, predominated. Subsequently, metagenomic shotgun sequencing was employed to identify possible functional pathways and carbohydrate-active enzymes (CAZymes). Carbohydrate catabolic pathways represented the main degradation pathways, and the fecal metagenome was enriched in the glycohydroside (GH) class of CAZymes. Additionally, the top GH families identified - GH43, GH2, GH13 and GH3 - are known to be associated with cellulytic, hemicellulytic and pectolytic activities. Finally, the CAZymes families identified in the African savanna elephant were compared with those found in the Asian elephant and it was demonstrated that there is a unique repository of CAZymes that could be leveraged in the biotechnological context such as the degradation of lignocellulose for the production of second-generation biofuels and energy.
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Affiliation(s)
- Louis Lategan du Preez
- Department of Animal Science, University of the Free State, Bloemfontein, Free State, South Africa
| | - Elzette van der Walt
- Department of Microbiology and Biochemistry, University of the Free State, Bloemfontein, Free State, South Africa
| | - Angel Valverde
- Department of Microbiology and Biochemistry, University of the Free State, Bloemfontein, Free State, South Africa
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Consejo Superior de Investigaciones Científicas, Salamanca, Spain
| | - Christopher Rothmann
- Department of Animal Science, University of the Free State, Bloemfontein, Free State, South Africa
- Department of Microbiology and Biochemistry, University of the Free State, Bloemfontein, Free State, South Africa
| | | | - Errol Duncan Cason
- Department of Animal Science, University of the Free State, Bloemfontein, Free State, South Africa
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Structure of an Alkaline Pectate Lyase and Rational Engineering with Improved Thermo-Alkaline Stability for Efficient Ramie Degumming. Int J Mol Sci 2022; 24:ijms24010538. [PMID: 36613981 PMCID: PMC9820310 DOI: 10.3390/ijms24010538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022] Open
Abstract
Alkaline pectate lyases have biotechnological applications in plant fiber processing, such as ramie degumming. Previously, we characterized an alkaline pectate lyase from Bacillus clausii S10, named BacPelA, which showed potential for enzymatic ramie degumming because of its high cleavage activity toward methylated pectins in alkaline conditions. However, BacPelA displayed poor thermo-alkaline stability. Here, we report the 1.78 Å resolution crystal structure of BacPelA in apo form. The enzyme has the characteristic right-handed β-helix fold of members of the polysaccharide lyase 1 family and shows overall structural similarity to them, but it displays some differences in the details of the secondary structure and Ca2+-binding site. On the basis of the structure, 10 sites located in flexible regions and showing high B-factor and positive ΔTm values were selected for mutation, aiming to improve the thermo-alkaline stability of the enzyme. Following site-directed saturation mutagenesis and screening, mutants A238C, R150G, and R216H showed an increase in the T5015 value at pH 10.0 of 3.0 °C, 6.5 °C, and 7.0 °C, respectively, compared with the wild-type enzyme, interestingly accompanied by a 24.5%, 46.6%, and 61.9% increase in activity. The combined mutant R150G/R216H/A238C showed an 8.5 °C increase in the T5015 value at pH 10.0, and an 86.1% increase in the specific activity at 60 °C, with approximately doubled catalytic efficiency, compared with the wild-type enzyme. Moreover, this mutant retained 86.2% activity after incubation in ramie degumming conditions (4 h, 60 °C, pH 10.0), compared with only 3.4% for wild-type BacPelA. The combined mutant increased the weight loss of ramie fibers in degumming by 30.2% compared with wild-type BacPelA. This work provides a thermo-alkaline stable, highly active pectate lyase with great potential for application in the textile industry, and also illustrates an effective strategy for rational design and improvement of pectate lyases.
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Suzuki H, Morishima T, Handa A, Tsukagoshi H, Kato M, Shimizu M. Biochemical Characterization of a Pectate Lyase AnPL9 from Aspergillus nidulans. Appl Biochem Biotechnol 2022; 194:5627-5643. [PMID: 35802235 DOI: 10.1007/s12010-022-04036-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2022] [Indexed: 11/26/2022]
Abstract
Pectinolytic enzymes have diverse industrial applications. Among these, pectate lyases act on the internal α-1,4-linkage of the pectate backbone, playing a critical role in pectin degradation. While most pectate lyases characterized thus far are of bacterial origin, fungi can also be excellent sources of pectinolytic enzymes. In this study, we performed biochemical characterization of the pectate lyase AnPL9 belonging to the polysaccharide lyase family 9 (PL9) from the filamentous fungus Aspergillus nidulans. Recombinant AnPL9 was produced using a Pichia pastoris expression system and purified. AnPL9 exhibited high activity on homogalacturonan (HG), pectin from citrus peel, pectin from apple, and the HG region in rhamnogalacturonan-I. Although digalacturonic acid and trigalacturonic acid were not degraded by AnPL9, tetragalacturonic acid was converted to 4,5-unsaturated digalacturonic acid and digalacturonic acid. These results indicate that AnPL9 degrades HG oligosaccharides with a degree of polymerization > 4. Furthermore, AnPL9 was stable within a neutral-to-alkaline pH range (pH 6.0-11.0). Our findings suggest that AnPL9 is a candidate pectate lyase for biotechnological applications in the food, paper, and textile industries. This is the first report on a fungal pectate lyase belonging to the PL9 family.
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Affiliation(s)
- Hiromitsu Suzuki
- Faculty of Agriculture, Meijo University, Nagoya, Aichi, 468-0073, Japan
| | - Toshiki Morishima
- Faculty of Agriculture, Meijo University, Nagoya, Aichi, 468-0073, Japan
| | - Atsuya Handa
- Faculty of Agriculture, Meijo University, Nagoya, Aichi, 468-0073, Japan
| | | | - Masashi Kato
- Faculty of Agriculture, Meijo University, Nagoya, Aichi, 468-0073, Japan
| | - Motoyuki Shimizu
- Faculty of Agriculture, Meijo University, Nagoya, Aichi, 468-0073, Japan.
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Zheng L, Xu Y, Li Q, Zhu B. Pectinolytic lyases: a comprehensive review of sources, category, property, structure, and catalytic mechanism of pectate lyases and pectin lyases. BIORESOUR BIOPROCESS 2021; 8:79. [PMID: 38650254 PMCID: PMC10992409 DOI: 10.1186/s40643-021-00432-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 08/16/2021] [Indexed: 12/22/2022] Open
Abstract
Pectate lyases and pectin lyases have essential roles in various biotechnological applications, such as textile industry, paper making, pectic wastewater pretreatment, juice clarification and oil extraction. They can effectively cleave the α-1,4-glycosidic bond of pectin molecules back bone by β-elimination reaction to produce pectin oligosaccharides. In this way, it will not generate highly toxic methanol and has the advantages of good enzymatic selectivity, less by-products, mild reaction conditions and high efficiency. However, numerous researches have been done for several decades; there are still no comprehensive reviews to summarize the recent advances of pectate lyases and pectin lyases. This review tries to fill this gap by providing all relevant information, including the substrate, origin, biochemical properties, sequence analysis, mode of action, the three-dimensional structure and catalytic mechanism.
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Affiliation(s)
- Ling Zheng
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, P. R. China
| | - Yinxiao Xu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, P. R. China
| | - Qian Li
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, P. R. China
| | - Benwei Zhu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, P. R. China.
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The Homogalacturonan Deconstruction System of Paenibacillus amylolyticus 27C64 Requires No Extracellular Pectin Methylesterase and Has Significant Industrial Potential. Appl Environ Microbiol 2020; 86:AEM.02275-19. [PMID: 32303547 PMCID: PMC7267202 DOI: 10.1128/aem.02275-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 04/08/2020] [Indexed: 11/20/2022] Open
Abstract
Pectin is an important structural polysaccharide found in most plant cell walls. In the environment, pectin degradation is part of the decomposition process that turns over dead plant material and is important to organisms that feed on plants. Industrially, pectinases are used to improve the quality of fruit juices and can also be used to process coffee cherries or tea leaves. These enzymes may also prove useful in reducing the environmental impact of paper and cotton manufacturing. This work is significant because it focuses on a Gram-positive bacterium that is evolutionarily distinct from other well-studied pectin-degrading organisms and differs from known systems in key ways. Most importantly, a simplified extracellular deconstruction process in this organism is able to break down pectins without first removing the methyl groups that inhibit other systems. Moreover, some of the enzymes described here have the potential to improve industrial processes that rely on pectin deconstruction. Paenibacillus amylolyticus 27C64, a Gram-positive bacterium with diverse plant cell wall polysaccharide deconstruction capabilities, was isolated previously from an insect hindgut. Previous work suggested that this organism’s pectin deconstruction system differs from known systems in that its sole pectin methylesterase is cytoplasmic, not extracellular. In this work, we have characterized the specific roles of key extracellular pectinases involved in homogalacturonan deconstruction, including four pectate lyases and one pectin lyase. We show that one newly characterized pectate lyase, PelC, has a novel substrate specificity, with a lower Km for highly methylated pectins than for polygalacturonic acid. PelC works synergistically with PelB, a high-turnover exo-pectate lyase that releases Δ4,5-unsaturated trigalacturonate as its major product. It is likely that PelC frees internal stretches of demethylated homogalacturonan which PelB can degrade. We also show that the sole pectin lyase has a high kcat value and rapidly depolymerizes methylated substrates. Three cytoplasmic GH105 hydrolases were screened for the ability to remove terminal unsaturated galacturonic acid residues from oligogalacturonide products produced by the action of extracellular lyases, and we found that two are active on demethylated oligogalacturonides. This work confirms that efficient homogalacturonan deconstruction in P. amylolyticus 27C65 does not require extracellular pectin methylesterase activity. Three of the extracellular lyases studied in this work are also thermostable, function well over a broad pH range, and have significant industrial potential. IMPORTANCE Pectin is an important structural polysaccharide found in most plant cell walls. In the environment, pectin degradation is part of the decomposition process that turns over dead plant material and is important to organisms that feed on plants. Industrially, pectinases are used to improve the quality of fruit juices and can also be used to process coffee cherries or tea leaves. These enzymes may also prove useful in reducing the environmental impact of paper and cotton manufacturing. This work is significant because it focuses on a Gram-positive bacterium that is evolutionarily distinct from other well-studied pectin-degrading organisms and differs from known systems in key ways. Most importantly, a simplified extracellular deconstruction process in this organism is able to break down pectins without first removing the methyl groups that inhibit other systems. Moreover, some of the enzymes described here have the potential to improve industrial processes that rely on pectin deconstruction.
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Wang Z, Xu B, Luo H, Meng K, Wang Y, Liu M, Bai Y, Yao B, Tu T. Production pectin oligosaccharides using Humicola insolens Y1-derived unusual pectate lyase. J Biosci Bioeng 2019; 129:16-22. [PMID: 31400994 DOI: 10.1016/j.jbiosc.2019.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/01/2019] [Accepted: 07/22/2019] [Indexed: 12/27/2022]
Abstract
The economical production of pectin oligosaccharides with a specific degree of polymerization and structure from agro-food waste is an industrially important process. This study identified a novel pectate lyase gene (plhy1) from the thermophilic cellulolytic fungus H. insolens Y1 and tested its ability to produce pectin oligosaccharides. The recombinant PLHY1 produced in Pichia pastoris was superior to other similar enzymes due to its high thermal and pH stability. PLHY1 demonstrated optimal enzymatic activity at 55°C and pH 10.0 in the presence of 0.4 mM Ca2+, and preferred methyl esterified substrates for digestion. High performance anion exchange chromatography-pulsed amperometric detector and ultra high performance liquid chromatography in combination with electrospray ionization tandem mass spectrometry analysis showed that galacturonic acid-oligosaccharides with a small degree of polymerization (4-6) were the major hydrolysates produced by the degradation of apple peel pectin by PLHY1. The properties of PLHY1 make it valuable for application in the agro-food industry for the production of pectin oligosaccharides.
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Affiliation(s)
- Zhiyun Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; College of Biological Sciences and Engineering, Jiangxi Agricultural University, Nanchang 330100, PR China
| | - Bo Xu
- College of Biological Sciences and Engineering, Jiangxi Agricultural University, Nanchang 330100, PR China
| | - Huiying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Kun Meng
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yuan Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Mengting Liu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yingguo Bai
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Tao Tu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
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Kamijo J, Sakai K, Suzuki H, Suzuki K, Kunitake E, Shimizu M, Kato M. Identification and characterization of a thermostable pectate lyase from Aspergillus luchuensis var. saitoi. Food Chem 2019; 276:503-510. [DOI: 10.1016/j.foodchem.2018.10.059] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 10/06/2018] [Accepted: 10/11/2018] [Indexed: 10/28/2022]
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Endophytic Paenibacillus amylolyticus KMCLE06 Extracted Dipicolinic Acid as Antibacterial Agent Derived via Dipicolinic Acid Synthetase Gene. Curr Microbiol 2018; 76:178-186. [PMID: 30498942 DOI: 10.1007/s00284-018-1605-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/23/2018] [Indexed: 01/15/2023]
Abstract
Bioactive natural compounds play pivotal roles in drug discovery and the emergence of multi-drug resistance pathogens demands the development of better/new drugs. Paenibacillus amylolyticus KMCLE06 endophytic bacterium isolated from the medicinal plant Coix lachryma-jobi were analyzed for the potential bioactive secondary metabolite compounds and its gene responsible within polyketide synthases (PKS) clusters. Ethyl acetate extraction of P. amylolyticus KMCLE06 showed significant antibacterial activity which was further processed to partial purification and characterization for bioactive compound. The foremost bioactive component in extraction was found to be dipicolinic acid (DPA). The antibacterial activity showed remarkable activity compared to the commercial standard DPA against both gram-positive and gram-negative pathogens. The MIC and MBC concentrations for partially purified extracted DPA ranged from 62.5 to 125 µg/ml and MBC from 208 to 250 µg/ml, respectively. Sequence analysis of gene amplified using degenerative primer, amplified 543 bp DNA region, revealing conserved putative open reading frame for dipicolinic acid synthetase (DpsA) key gene to produce DPA in most endospore forming bacteria. A search in the structural database for DpsA revealed significant homologous match with enoyl reductase one of the PKS type 1 module protein. This emphasizes endophytic P. amylolyticus KMCLE06 bacteria has presence of spoVF operon producing DPA via dipicolinic acid synthetase and lacks the polyketide synthase type 1 module cluster gene in its genome. And the bioactive compound DPA extracted acts as a stable remarkable antibacterial agent which can be potent compound for multi-resistance pathogens.
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Paenibacillus amylolyticus 27C64 has a diverse set of carbohydrate-active enzymes and complete pectin deconstruction system. J Ind Microbiol Biotechnol 2018; 46:1-11. [PMID: 30377865 PMCID: PMC6339884 DOI: 10.1007/s10295-018-2098-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/21/2018] [Indexed: 12/24/2022]
Abstract
A draft genome of Paenibacillus amylolyticus 27C64 was assembled and a total of 314 putative CAZymes in 108 different families were identified. Comparison to well-studied polysaccharide-degrading organisms revealed that P. amylolyticus 27C64 has as many or more putative CAZymes than most of these organisms. Four different pectic substrates and xylan supported growth but cellulose was not utilized. Measurement of enzyme activities in culture supernatants revealed low levels of cellulase activity, high levels of xylanase activity, and pectinase activities that adapted to the specific polysaccharides provided. Relative expression levels of each putative pectinase in cells grown with and without three different pectic substrates were evaluated with RT-qPCR and distinct sets of genes upregulated in response to homogalacturonan, methylated homogalacturonan, and rhamnogalacturonan I were identified. It is also noted that this organism's pectinolytic system differs from other well-studied systems and contains enzymes which are of value for further study.
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Improving the specific activity and thermo-stability of alkaline pectate lyase from Bacillus subtilis 168 for bioscouring. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2017.11.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Directed Evolution and Structural Analysis of Alkaline Pectate Lyase from the Alkaliphilic Bacterium Bacillus sp. Strain N16-5 To Improve Its Thermostability for Efficient Ramie Degumming. Appl Environ Microbiol 2015; 81:5714-23. [PMID: 26070675 DOI: 10.1128/aem.01017-15] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 06/07/2015] [Indexed: 11/20/2022] Open
Abstract
Thermostable alkaline pectate lyases have potential applications in the textile industry as an alternative to chemical-based ramie degumming processes. In particular, the alkaline pectate lyase from Bacillus sp. strain N16-5 (BspPelA) has potential for enzymatic ramie degumming because of its high specific activity under extremely alkaline conditions without the requirement for additional Ca(2+). However, BspPelA displays poor thermostability and is inactive after incubation at 50°C for only 30 min. Here, directed evolution was used to improve the thermostability of BspPelA for efficient and stable degumming. After two rounds of error-prone PCR and screening of >12,000 mutants, 10 mutants with improved thermostability were obtained. Sequence analysis and site-directed mutagenesis revealed that single E124I, T178A, and S271G substitutions were responsible for improving thermostability. Structural and molecular dynamic simulation analysis indicated that the formation of a hydrophobic cluster and new H-bond networks was the key factor contributing to the improvement in thermostability with these three substitutions. The most thermostable combined mutant, EAET, exhibited a 140-fold increase in the t50 (time at which the enzyme loses 50% of its initial activity) value at 50°C, accompanied by an 84.3% decrease in activity compared with that of wild-type BspPelA, while the most advantageous combined mutant, EA, exhibited a 24-fold increase in the t50 value at 50°C, with a 23.3% increase in activity. Ramie degumming with the EA mutant was more efficient than that with wild-type BspPelA. Collectively, our results suggest that the EA mutant, exhibiting remarkable improvements in thermostability and activity, has the potential for applications in ramie degumming in the textile industry.
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Biochemical characteristics of an alkaline pectate lyase PelA from Volvariella volvacea: roles of the highly conserved N-glycosylation site in its secretion and activity. Appl Microbiol Biotechnol 2014; 99:3447-58. [DOI: 10.1007/s00253-014-6146-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 10/06/2014] [Accepted: 10/09/2014] [Indexed: 02/05/2023]
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Liang C, Gui X, Zhou C, Xue Y, Ma Y, Tang SY. Improving the thermoactivity and thermostability of pectate lyase from Bacillus pumilus for ramie degumming. Appl Microbiol Biotechnol 2014; 99:2673-82. [PMID: 25287558 DOI: 10.1007/s00253-014-6091-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 08/27/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
Abstract
Thermostable alkaline pectate lyases can be potentially used for enzymatically degumming ramie in an environmentally sustainable manner and as an alternative to the currently used chemical-based ramie degumming processes. To assess its potential applications, pectate lyase from Bacillus pumilus (ATCC 7061) was cloned and expressed in Escherichia coli. Evolutionary strategies were applied to generate efficient ramie degumming enzymes. Obtained from site-saturation mutagenesis and random mutagenesis, the best performing mutant enzyme M3 exhibited a 3.4-fold higher specific activity on substrate polygalacturonic acid, compared with the wild-type enzyme. Furthermore, the half-life of inactivation at 50 °C for M3 mutant extended to over 13 h. In contrast, the wild-type enzyme was completely inactivated in less than 10 min under the same conditions. An upward shift in the optimal reaction temperature of M3 mutant, to 75 °C, was observed, which was 10 °C higher than that of the wild-type enzyme. Kinetic parameter data revealed that the catalysis efficiency of M3 mutant was higher than that of the wild-type enzyme. Ramie degumming with M3 mutant was also demonstrated to be more efficient than that with the wild-type enzyme. Collectively, our results suggest that the M3 mutant, with remarkable improvements in thermoactivity and thermostability, has potential applications for ramie degumming in the textile industry.
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Affiliation(s)
- Chaoning Liang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, 100101, Beijing, People's Republic of China
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A pectate lyase from a deep subseafloor Georgenia muralis with unusual molecular characteristics. Extremophiles 2014; 19:119-25. [DOI: 10.1007/s00792-014-0691-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 08/28/2014] [Indexed: 10/24/2022]
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Li X, Wang H, Zhou C, Ma Y, Li J, Song J. Cloning, expression and characterization of a pectate lyase from Paenibacillus sp. 0602 in recombinant Escherichia coli. BMC Biotechnol 2014; 14:18. [PMID: 24612647 PMCID: PMC4007691 DOI: 10.1186/1472-6750-14-18] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 03/04/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Biotechnological applications of microbial pectate lyases (Pels) in plant fiber processing are considered as environmentally friendly. As such, they become promising substitutes for conventional chemical degumming process. Since applications of Pels in various fields are widening, it is necessary to explore new pectolytic microorganisms and enzymes for efficient and effective usage. Here, we describe the cloning, expression, characterization and application of the recombinant Pel protein from a pectolytic bacterium of the genus Paenibacillus in Escherichia coli. RESULTS A Pel gene (pelN) was cloned using degenerate PCR and inverse PCR from the chromosomal DNA of Paenibacillus sp. 0602. The open reading frame of pelN encodes a 30 amino acid signal peptide and a 445 amino acid mature protein belonging to the polysaccharide lyase family 1. The maximum Pel activity produced by E. coli in shake flasks reached 2,467.4 U mL⁻¹, and the purified recombinant enzyme exhibits a specific activity of 2,060 U mg⁻¹ on polygalacturonic acid (PGA). The maximum activity was observed in a buffer with 5 mM Ca²⁺ at pH 9.8 and 65°C. PelN displays a half-life of around 9 h and 42 h at 50°C and 45°C, respectively. The biochemical treatment achieved the maximal reduction of percentage weight (30.5%) of the ramie bast fiber. CONCLUSIONS This work represents the first study that describes the extracellular expression of a Pel gene from Paenibacillus species in E. coli. The high yield of the extracellular overexpression, relevant thermostability and efficient degumming using combined treatments indicate its strong potential for large-scale industrial production.
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Affiliation(s)
| | | | | | - Yanhe Ma
- National Engineering Laboratory for Industrial Enzymes and Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China.
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Replacing a suite of commercial pectinases with a single enzyme, pectate lyase B, in Saccharomyces cerevisiae fermentations of cull peaches. J Ind Microbiol Biotechnol 2014; 41:679-86. [PMID: 24585204 DOI: 10.1007/s10295-013-1394-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/16/2013] [Indexed: 10/25/2022]
Abstract
Fermentation of pectin-rich biomass with low concentrations of polysaccharides requires some treatment of the pectin, but does not need complete degradation of the polysaccharide to reach maximum ethanol yields. Cull peaches, whole rotten fruits that are not suitable for sale, contain high concentrations of glucose (27.7% dw) and fructose (29.3% dw) and low amounts of cellulose (2.8% dw), hemicellulose (4.5% dw) and pectin (5.6% dw). Amounts of commercial saccharification enzymes, cellulase and cellobiase can be significantly decreased and commercial pectinase mixtures can be replaced completely with a single enzyme, pectate lyase (PelB), while maintaining ethanol yields above 90% of the theoretical maximum. PelB does not completely degrade pectin; it only releases short chain oligogalacturonides. However, the activity of PelB is sufficient for the fermentation process, and its addition to fermentations without commercial pectinase increases ethanol production by ~12%.
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Characterization and high-level expression of a metagenome-derived alkaline pectate lyase in recombinant Escherichia coli. Process Biochem 2014. [DOI: 10.1016/j.procbio.2013.10.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Abstract
Here, we report draft genomes of Paenibacillus alvei strains A6-6i and TS-15, which were isolated, respectively, from plant material and soil in the Virginia Eastern Shore (VES) tomato growing area. An array of genes related to antimicrobial biosynthetic pathways have been identified with whole-genome analyses of these strains.
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New and old microbial communities colonizing a seventeenth-century wooden church. Folia Microbiol (Praha) 2013; 59:45-51. [DOI: 10.1007/s12223-013-0265-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 06/28/2013] [Indexed: 10/26/2022]
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Visi DK, D’Souza N, Ayre BG, Webber III CL, Allen MS. Investigation of the bacterial retting community of kenaf (Hibiscus cannabinus) under different conditions using next-generation semiconductor sequencing. ACTA ACUST UNITED AC 2013; 40:465-75. [DOI: 10.1007/s10295-013-1242-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 02/08/2013] [Indexed: 10/27/2022]
Abstract
Abstract
The microbial communities associated with kenaf (Hibiscus cannabinus) plant fibers during retting were determined in an effort to identify possible means of accelerating this process for industrial scale-up. Microbial communities were identified by semiconductor sequencing of 16S rRNA gene amplicons from DNA harvested from plant-surface associated samples and analyzed using an Ion Torrent PGM. The communities were sampled after 96 h from each of three different conditions, including amendments with pond water, sterilized pond water, or with a mixture of pectinolytic bacterial isolates. Additionally, plants from two different sources and having different pretreatment conditions were compared. We report that the best retting communities are dominated by members of the order Clostridiales. These bacteria appear to be naturally associated with the plant material, although slight variations between source materials were found. Additionally, heavy inoculations of pectinolytic bacteria established themselves and in addition their presence facilitated the rapid dominance of the original plant-associated Clostridiales. These data suggest that members of the order Clostridiales dominate the community and are most closely associated with efficient and effective retting. The results further suggest that establishment of the community structure is first driven by the switch to anaerobic conditions, and subsequently by possible competition for nitrogen. These findings reveal important bacterial groups involved in fiber retting, and suggest mechanisms for the manipulation of the community and retting efficiency by modifying nutrient availability.
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Affiliation(s)
- David K Visi
- grid.266871.c 0000000097656057 Department of Forensics and Investigative Genetics University of North Texas Health Science Center 76107 Ft. Worth TX USA
- grid.266869.5 000000011008957X Department of Biological Sciences University of North Texas 76203-3677 Denton TX USA
| | - Nandika D’Souza
- grid.266869.5 000000011008957X Department of Mechanical and Energy Engineering University of North Texas 76203-3677 Denton TX USA
| | - Brian G Ayre
- grid.266869.5 000000011008957X Department of Biological Sciences University of North Texas 76203-3677 Denton TX USA
| | - Charles L Webber III
- grid.463419.d 0000 0004 0404 0958 Sugarcane Research Unit USDA, ARS 70361 Houma LA USA
| | - Michael S Allen
- grid.266871.c 0000000097656057 Department of Forensics and Investigative Genetics University of North Texas Health Science Center 76107 Ft. Worth TX USA
- grid.266869.5 000000011008957X Department of Biological Sciences University of North Texas 76203-3677 Denton TX USA
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Khan M, Nakkeeran E, Umesh-Kumar S. Potential Application of Pectinase in Developing Functional Foods. Annu Rev Food Sci Technol 2013. [DOI: 10.1146/annurev-food-030212-182525] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The understanding that enzymatic degradation of fruit pectin can clarify juices and improve juice yields resulted in the search for microbial pectinases and application in vegetable- and fruit-processing industries. Identified enzymes were classified on the basis of their catalytic activity to pectin or its derivatives and in terms of industrial use. Discovery of gene sequences that coded the enzymes, protein engineering, and molecular biology tools resulted in defined microbial strains that over-produced the enzymes for cost-effective technologies. Recent perspectives on the use of pectin and its derivatives as dietary fibers suggest enzymatic synthesis of the right oligomers from pectin for use in human nutrition. While summarizing the activities of pectin-degrading enzymes, their industrial applications, and gene sources, this review projects another application for pectinases, which is the use of enzymatically derived pectin moieties in functional food preparation.
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Affiliation(s)
- Mahejibin Khan
- Department of Food Microbiology, Central Food Technological Research Institute (CSIR), Mysore 570020, India
| | - Ekambaram Nakkeeran
- School of Biosciences and Technology, Vellore Institute of Technology University, Vellore 632014, India
| | - Sukumaran Umesh-Kumar
- Department of Food Microbiology, Central Food Technological Research Institute (CSIR), Mysore 570020, India
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Zhou J, Dong Y, Gao Y, Tang X, Li J, Yang Y, Xu B, Xie Z, Huang Z. Characterization of a family 3 polysaccharide lyase with broad temperature adaptability, thermo-alkali stability, and ethanol tolerance. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-012-0122-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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