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Çelik Doğan C, Yüksel Dolgun HT, İkiz S, Kırkan Ş, Parın U. Detection of the Microbial Composition of Some Commercial Fermented Liquid Products via Metagenomic Analysis. Foods 2023; 12:3538. [PMID: 37835192 PMCID: PMC10572611 DOI: 10.3390/foods12193538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 10/15/2023] Open
Abstract
The fermented liquid sector is developing all over the world due to its contribution to health. Our study has contributed to the debate about whether industrially manufactured fermented liquids live up to their claims by analyzing pathogens and beneficial bacteria using a 16S rRNA sequencing technique called metagenomic analysis. Paenibacillus, Lentibacillus, Bacillus, Enterococcus, Levilactobacillus, and Oenococcus were the most abundant bacterial genera observed as potential probiotics. Pseudomonas stutzeri, Acinetobacter, and Collimonas, which have plant-growth-promoting traits, were also detected. The fact that we encounter biocontroller bacteria that promote plant growth demonstrates that these organisms are widely used in foods and emphasizes the necessity of evaluating them in terms of public health. Their potential applications in agriculture may pose a danger to food hygiene and human health in the long term, so our data suggest that this should be evaluated.
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Affiliation(s)
- Cansu Çelik Doğan
- Food Technology Program, Food Processing Department, Vocational School of Veterinary Medicine, Istanbul University-Cerrahpaşa, 34320 Istanbul, Türkiye
| | - Hafize Tuğba Yüksel Dolgun
- Department of Microbiology, Faculty of Veterinary Medicine, Aydın Adnan Menderes University, 09010 Aydın, Türkiye; (H.T.Y.D.); (Ş.K.); (U.P.)
| | - Serkan İkiz
- Department of Microbiology, Faculty of Veterinary Medicine, Istanbul University-Cerrahpaşa, 34320 Istanbul, Türkiye;
| | - Şükrü Kırkan
- Department of Microbiology, Faculty of Veterinary Medicine, Aydın Adnan Menderes University, 09010 Aydın, Türkiye; (H.T.Y.D.); (Ş.K.); (U.P.)
| | - Uğur Parın
- Department of Microbiology, Faculty of Veterinary Medicine, Aydın Adnan Menderes University, 09010 Aydın, Türkiye; (H.T.Y.D.); (Ş.K.); (U.P.)
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2
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Mendonça M, Barroca M, Collins T. Endo-1,4-β-xylanase-containing glycoside hydrolase families: Characteristics, singularities and similarities. Biotechnol Adv 2023; 65:108148. [PMID: 37030552 DOI: 10.1016/j.biotechadv.2023.108148] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 04/02/2023] [Accepted: 04/04/2023] [Indexed: 04/09/2023]
Abstract
Endo-1,4-β-xylanases (EC 3.2.1.8) are O-glycoside hydrolases that cleave the internal β-1,4-D-xylosidic linkages of the complex plant polysaccharide xylan. They are produced by a vast array of organisms where they play critical roles in xylan saccharification and plant cell wall hydrolysis. They are also important industrial biocatalysts with widespread application. A large and ever growing number of xylanases with wildly different properties and functionalites are known and a better understanding of these would enable a more effective use in various applications. The Carbohydrate-Active enZYmes database (CAZy), which classifies evolutionarily related proteins into a glycoside hydrolase family-subfamily organisational scheme has proven powerful in understanding these enzymes. Nevertheless, ambiguity currently exists as to the number of glycoside hydrolase families and subfamilies harbouring catalytic domains with true endoxylanase activity and as to the specific characteristics of each of these families/subfamilies. This review seeks to clarify this, identifying 9 glycoside hydrolase families containing enzymes with endo-1,4-β-xylanase activity and discussing their properties, similarities, differences and biotechnological perspectives. In particular, substrate specificities and hydrolysis patterns and the structural determinants of these are detailed, with taxonomic aspects of source organisms being also presented. Shortcomings in current knowledge and research areas that require further clarification are highlighted and suggestions for future directions provided. This review seeks to motivate further research on these enzymes and especially of the lesser known endo-1,4-β-xylanase containing families. A better understanding of these enzymes will serve as a foundation for the knowledge-based development of process-fitted endo-1,4-β-xylanases and will accelerate their development for use with even the most recalcitrant of substrates in the biobased industries of the future.
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3
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Hu R, Jiang X, Yang H, Liu G. Selection signature analysis reveals RDH5 performed key function in vision during sheep domestication process. Arch Anim Breed 2023. [DOI: 10.5194/aab-66-81-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Abstract. As one of the most successful domesticated animals in the Neolithic age,
sheep gradually migrated all over the world with human activities. During the
domestication process, remarkable changes have taken place in morphology,
physiology, and behavior, resulting in different breeds with different
characters via artificial and natural selection. However, the genetic
background responsible for these phenotypic variations remains largely
unclear. Here, we used whole genome resequencing technology to compare and
analyze the genome differences between Asiatic mouflon wild sheep (Ovis orientalis) and Hu
sheep (Ovis aries). A total of 755 genes were positively selected in the process of
domestication and selection, and the genes related to sensory perception had
directional evolution in the autosomal region, such as OPRL1, LEF1, TAS1R3, ATF6, VSX2, MYO1A, RDH5, and some novel
genes. A missense mutation of c.T722C/p.M241T in exon 4 of RDH5 existing in sheep
were found, and the T allele was completely fixed in Hu sheep. In addition, the
mutation with the C allele reduced the retinol dehydrogenase activity encoding
by RDH5, which can impair retinoic acid metabolism and further influenced the visual
cycle. Overall, our results showed significant enrichment for positively
selected genes involved in sensory perception development during sheep
domestication; RDH5 and its variants may be related to the retinal degeneration
in sheep. We infer that the wild sheep ancestors with weaker visual sensitivity
were weeded out by humans, and the mutation was selective, swept by the dual
pressures of natural and artificial selection.
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4
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Tan S, Tao X, Zheng P, Chen P, Yu X, Li N, Gao T, Wu D. Thermostability modification of β-mannanase from Aspergillus niger via flexibility modification engineering. Front Microbiol 2023; 14:1119232. [PMID: 36891394 PMCID: PMC9986629 DOI: 10.3389/fmicb.2023.1119232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 01/06/2023] [Indexed: 02/22/2023] Open
Abstract
Introduction β-Mannanases can hydrolyze mannans, which are widely available in nature. However, the optimum temperature of most β-mannanases is too low to be directly utilized in industry. Methods To further improve the thermostability of Anman (mannanase from Aspergillus niger CBS513.88), B-factor and Gibbs unfolding free energy change were used to modify the flexible of Anman, and then combined with multiple sequence alignment and consensus mutation to generate an excellent mutant. At last, we analyzed the intermolecular forces between Anman and the mutant by molecular dynamics simulation. Results The thermostability of combined mutant mut5 (E15C/S65P/A84P/A195P/T298P) was increased by 70% than the wild-type Amman at 70°C, and the melting temperature (Tm) and half-life (t1/2) values were increased by 2°C and 7.8-folds, respectively. Molecular dynamics simulation showed reduced flexibility and additional chemical bonds in the region near the mutation site. Discussion These results indicate that we obtained a Anman mutant that is more suitable for industrial application, and they also confirm that a combination of rational and semi-rational techniques is helpful for screening mutant sites.
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Affiliation(s)
- Shundong Tan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xiumei Tao
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Pu Zheng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Pengcheng Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xiaowei Yu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Ning Li
- Guangzhou Puratos Food Co., Ltd., Guangzhou, China
| | - Tiecheng Gao
- Guangzhou Puratos Food Co., Ltd., Guangzhou, China
| | - Dan Wu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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5
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Xylan Deconstruction by Thermophilic Thermoanaerobacterium bryantii Hemicellulases Is Stimulated by Two Oxidoreductases. Catalysts 2022. [DOI: 10.3390/catal12020182] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Thermoanaerobacterium bryantii strain mel9T is a thermophilic bacterium isolated from a waste pile of a corn-canning factory. The genome of T. bryantii mel9T was sequenced and a hemicellulase gene cluster was identified. The cluster encodes seven putative enzymes, which are likely an endoxylanase, an α-glucuronidase, two oxidoreductases, two β-xylosidases, and one acetyl xylan esterase. These genes were designated tbxyn10A, tbagu67A, tbheoA, tbheoB, tbxyl52A, tbxyl39A, and tbaxe1A, respectively. Only TbXyn10A released reducing sugars from birchwood xylan, as shown by thin-layer chromatography analysis. The five components of the hemicellulase cluster (TbXyn10A, TbXyl39A, TbXyl52A, TbAgu67A, and TbAxe1A) functioned in synergy to hydrolyze birchwood xylan. Surprisingly, the two putative oxidoreductases increased the enzymatic activities of the gene products from the xylanolytic gene cluster in the presence of NADH and manganese ions. The two oxidoreductases were therefore named Hemicellulase-Enhancing Oxidoreductases (HEOs). All seven enzymes were thermophilic and acted in synergy to degrade xylans at 60 °C. Except for TbXyn10A, the other enzymes encoded by the gene cluster were conserved with high amino acid identities (85–100%) in three other Thermoanaerobacterium species. The conservation of the gene cluster is, therefore, suggestive of an important role of these enzymes in xylan degradation by these bacteria. The mechanism for enhancement of hemicellulose degradation by the HEOs is under investigation. It is anticipated, however, that the discovery of these new actors in hemicellulose deconstruction will have a significant impact on plant cell wall deconstruction in the biofuel industry.
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Huang JJ, Wei T, Ye ZW, Zheng QW, Jiang BH, Han WF, Ye AQ, Han PY, Guo LQ, Lin JF. Microbial Cell Factory of Baccatin III Preparation in Escherichia coli by Increasing DBAT Thermostability and in vivo Acetyl-CoA Supply. Front Microbiol 2022; 12:803490. [PMID: 35095813 PMCID: PMC8790024 DOI: 10.3389/fmicb.2021.803490] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 12/09/2021] [Indexed: 12/04/2022] Open
Abstract
Given the rapid development of genome mining in this decade, the substrate channel of paclitaxel might be identified in the near future. A robust microbial cell factory with gene dbat, encoding a key rate-limiting enzyme 10-deacetylbaccatin III-10-O-transferase (DBAT) in paclitaxel biosynthesis to synthesize the precursor baccatin III, will lay out a promising foundation for paclitaxel de novo synthesis. Here, we integrated gene dbat into the wild-type Escherichia coli BW25113 to construct strain BWD01. Yet, it was relatively unstable in baccatin III synthesis. Mutant gene dbat S189V with improved thermostability was screened out from a semi-rational mutation library of DBAT. When it was over-expressed in an engineered strain N05 with improved acetyl-CoA generation, combined with carbon source optimization of fermentation engineering, the production level of baccatin III was significantly increased. Using this combination, integrated strain N05S01 with mutant dbat S189V achieved a 10.50-fold increase in baccatin III production compared with original strain BWD01. Our findings suggest that the combination of protein engineering and metabolic engineering will become a promising strategy for paclitaxel production.
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Affiliation(s)
- Jia-jun Huang
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Tao Wei
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Zhi-wei Ye
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Qian-wang Zheng
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Bing-hua Jiang
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Wen-feng Han
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - An-qi Ye
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Pei-yun Han
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Li-qiong Guo
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Jun-fang Lin
- Department of Bioengineering, College of Food Science, Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
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Chen H, Liu C, Xiang M, Yu J, Xia Y, Hu X, Wang D, Tao B, Zhang Y, Cheng L. Contribution of the mutation rs8193069 in TLR4 to mastitis resistance and performance in Holstein cows in southern China. Vet Med Sci 2021; 8:357-366. [PMID: 34812595 PMCID: PMC8788991 DOI: 10.1002/vms3.671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Bovine mastitis has become increasingly important issues for farmers and consumers, leading to large economic losses in the dairy industry worldwide. Because treatment of mastitis is difficult and costly, improved mastitis resistance through selective breeding would be advantageous. The toll-like receptor 4 (TLR4) is an important player in recognising pathogens and activating immune responses. However, its roles in mastitis occurrence and the underlying molecular mechanisms are unclear. In this study, a single nucleotide polymorphism, rs8193069 (T → C) in TLR4 gene was detected in a Holstein cow resource population in southern China. Association analysis with 5-year production traits, haematology, and biochemistry parameters revealed that individuals with genotype CC had significantly lower somatic cell counts (SCC), lower fat percentage, but higher 305-day milk (p < 0.05) and total milk yield (p < 0.01). Both genotypes CC and CT had lower lymphocyte counts (#LYMPH) (p < 0.01) and basophil counts (#BASO) (p < 0.05) than TT. Genotype CC had a less level of triglyceride (p < 0.01) and creatine kinase (p < 0.05) than CT. Further analysis based on the production data revealed significant positive correlations between SCC and #LYMPH. Analysis of TLR4 protein structure and properties suggested that the missense mutation on the 674th amino acid from Thr to Ile reduced the flexibility and hydrophilicity of TIR domain, implying a weakened binding ability of TLR4 to its adaptors. In conclusion, allele C of rs8193069 was the major allele in Holstein cows that indicated a greater genetic potential to mastitis resistance and milk yields, probably via the LPS-TLR4 inflammatory signalling. This study offers a marker to improve mastitis resistance in the dairy cow population in southern China.
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Affiliation(s)
- Hongbo Chen
- Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan, P.R. China
| | - Chenhui Liu
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Min Xiang
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Jie Yu
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Yu Xia
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Xiuzhong Hu
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Dingfa Wang
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Bifei Tao
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
| | - Yongjin Zhang
- Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan, P.R. China
| | - Lei Cheng
- Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, P.R. China
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8
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Liu C, Jiang X, Chi S, Bo D, Liu G. Contribution of the mutation T865G in TPH1 gene to the genetic potentiality of housed Mongolian sheep to year-round breeding. Reprod Domest Anim 2021; 56:1406-1412. [PMID: 34390051 DOI: 10.1111/rda.14005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/11/2021] [Indexed: 01/13/2023]
Abstract
Seasonal breeding is widespread in sheep and significantly affects the development of the housed sheep industry. To improve and balance the reproduction performance of sheep, year-round breeding has the goal of modern sheep farming. The tryptophan hydroxylase (TPH), which initiates and regulates biosynthesis of melatonin, is an important player in the formation of mammalian year-round breeding. However, little is known about its role in regulation of sheep seasonal breeding. In this study, a missense mutation, T865G in TPH1 gene was detected in 328 individuals of six Mongolian sheep groups. It was positively selected among Mongolian sheep. This mutation may appear between 13,683 and 350,973 years ago and only exist in Hu sheep now. In Hu sheep, the frequency of allele T was 89.66%, and that of allele G was 10.34%. The TPH1 protein structure and property analysis suggested that this mutation from T to G affect the three-dimensional structure and reduce the hydropathicity of catalytic core. When the allele is T, the protein activity is twice that of the allele G, and their difference was significant (p < .05). In conclusion, T865G is an ancient mutation of TPH1 gene and affects the function of TPH protein, which may contribute to the genetic potentiality of Mongolian sheep to year-round breeding.
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Affiliation(s)
- Chenhui Liu
- Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Wuhan, China.,Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Xunping Jiang
- Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Wuhan, China
| | - Shaxuan Chi
- Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Wuhan, China
| | - Dongdong Bo
- Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Wuhan, China
| | - Guiqiong Liu
- Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Wuhan, China
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Talens-Perales D, Jiménez-Ortega E, Sánchez-Torres P, Sanz-Aparicio J, Polaina J. Phylogenetic, functional and structural characterization of a GH10 xylanase active at extreme conditions of temperature and alkalinity. Comput Struct Biotechnol J 2021; 19:2676-2686. [PMID: 34093984 PMCID: PMC8148631 DOI: 10.1016/j.csbj.2021.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/29/2021] [Accepted: 05/01/2021] [Indexed: 01/31/2023] Open
Abstract
Endoxylanases active under extreme conditions of
temperature and alkalinity can replace the use of highly pollutant chemicals in
the pulp and paper industry. Searching for enzymes with these properties, we
carried out a comprehensive bioinformatics study of the GH10 family. The
phylogenetic analysis allowed the construction of a radial cladogram in which
protein sequences putatively ascribed as thermophilic and alkaliphilic appeared
grouped in a well-defined region of the cladogram, designated TAK Cluster. One
among five TAK sequences selected for experimental analysis (Xyn11) showed
extraordinary xylanolytic activity under simultaneous conditions of high
temperature (90 °C) and alkalinity (pH 10.5). Addition of a carbohydrate binding
domain (CBM2) at the C-terminus of the protein sequence further improved the
activity of the enzyme at high pH. Xyn11 structure, which has been solved at
1.8 Å resolution by X-ray crystallography, reveals an unusually high number of
hydrophobic, ionic and hydrogen bond atomic interactions that could account for
the enzyme’s extremophilic nature.
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Affiliation(s)
- David Talens-Perales
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
| | - Elena Jiménez-Ortega
- Institute of Physical-Chemistry Rocasolano, Spanish National Research Council (CSIC), Madrid, Spain
| | - Paloma Sánchez-Torres
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
| | - Julia Sanz-Aparicio
- Institute of Physical-Chemistry Rocasolano, Spanish National Research Council (CSIC), Madrid, Spain
| | - Julio Polaina
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
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10
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Zhu C, Chen Y, Isupov MN, Littlechild JA, Sun L, Liu X, Wang Q, Gong H, Dong P, Zhang N, Wu Y. Structural Insights into a Novel Esterase from the East Pacific Rise and Its Improved Thermostability by a Semirational Design. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:1079-1090. [PMID: 33445864 DOI: 10.1021/acs.jafc.0c06338] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Lipolytic enzymes are essential biocatalysts in food processing as well as pharmaceutical and pesticide industries, catalyzing the cleavage of ester bonds in a variety of acyl chain substrates. Here, we report the crystal structure of an esterase from the deep-sea hydrothermal vent of the East Pacific Rise (EprEst). The X-ray structure of EprEst in complex with the ligand, acetate, has been determined at 2.03 Å resolution. The structure reveals a unique spatial arrangement and orientation of the helix cap domain and α/β hydrolase domain, which form a substrate pocket with preference for short-chain acyl groups. Molecular docking analysis further demonstrated that the active site pocket could accommodate p-nitrophenyl (pNP) carboxyl ligands of varying lengths (≤6 C atoms), with pNP-butyrate ester predicted to have the highest binding affinity. Additionally, the semirational design was conducted to improve the thermostability of EprEst by enzyme engineering based on the established structure and multiple sequence alignment. A mutation, K114P, introduced in the hinge region of the esterase, which displayed increased thermostability and enzyme activity. Collectively, the structural and functional data obtained herein could be used as basis for further protein engineering to ultimately expand the scope of industrial applications of marine-derived lipolytic enzymes.
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Affiliation(s)
- Chunhua Zhu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China
| | - Yayu Chen
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Michail N Isupov
- Henry Wellcome Building for Biocatalysis, Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, United Kingdom
| | - Jennifer A Littlechild
- Henry Wellcome Building for Biocatalysis, Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, United Kingdom
| | - Lifang Sun
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Xiaodong Liu
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Qianchao Wang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Gong
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China
| | - Panpan Dong
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Na Zhang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Yunkun Wu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Fujian Normal University, Fuzhou 350117, China
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11
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Differential antioxidant activity of glucuronoxylooligosaccharides (UXOS) and arabinoxylooligosaccharides (AXOS) produced by two novel xylanases. Int J Biol Macromol 2020; 155:1075-1083. [DOI: 10.1016/j.ijbiomac.2019.11.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/24/2019] [Accepted: 11/07/2019] [Indexed: 01/09/2023]
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12
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Azouz RAM, Hegazy UM, Said MM, Bassuiny RI, Salem AM, Fahmy AS. Improving the catalytic efficiency of thermostable Geobacillus stearothermophilus xylanase XT6 by single-amino acid substitution. J Biochem 2020; 167:203-215. [PMID: 31617574 DOI: 10.1093/jb/mvz086] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 10/02/2019] [Indexed: 01/09/2023] Open
Abstract
Directed evolution using error-prone polymerase chain reaction was employed in the current study to enhance the catalytic efficiency of a thermostable Geobacillus stearothermophilus xylanase XT6 parent. High-throughput screening identified two variants with enhanced activity. Sequencing analysis revealed the presence of a single-amino acid substitution (P209L or V161L) in each variant. The maximum activity of mutant V161L and P209L was at 85°C and 70°C, respectively. Both mutants exhibited maximum activity at pH 7. The thermal and alkaline tolerance of mutant V161L only were markedly improved. The two mutants were more resistant to ethanol inhibition than the parent. Substrate specificity of the two mutants was shifted from beechwood xylan to birchwood xylan. The potential of the two mutants to hydrolyze rice straw and sugarcane bagasse increased. Both turnover number (kcat) and catalytic efficiency (kcat/kM) increased 12.2- and 5.7-folds for variant P209L and 13- and 6.5-folds for variant V161L, respectively, towards birchwood xylan. Based on the previously published crystal structure of extracellular G. stearothermophilus xylanase XT6, V161L and P209L mutation locate on βα-loops. Conformational changes of the respective loops could potentiate the loop swinging, product release and consequently result in enhancement of the catalytic performance.
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Affiliation(s)
- Rasha A M Azouz
- Genetic Engineering and Biotechnology Research Division, Molecular Biology Department, National Research Centre, El-Behouth Street, Dokki, 12622 Giza, Egypt
| | - Usama M Hegazy
- Genetic Engineering and Biotechnology Research Division, Molecular Biology Department, National Research Centre, El-Behouth Street, Dokki, 12622 Giza, Egypt
| | - Mahmoud M Said
- Faculty of Science, Department of Biochemistry, Ain Shams University, El-Khalyfa El-Mamoun Street, Abbasya, 11566 Cairo, Egypt
| | - Roqaya I Bassuiny
- Genetic Engineering and Biotechnology Research Division, Molecular Biology Department, National Research Centre, El-Behouth Street, Dokki, 12622 Giza, Egypt
| | - Ahmed M Salem
- Faculty of Science, Department of Biochemistry, Ain Shams University, El-Khalyfa El-Mamoun Street, Abbasya, 11566 Cairo, Egypt
| | - Afaf S Fahmy
- Genetic Engineering and Biotechnology Research Division, Molecular Biology Department, National Research Centre, El-Behouth Street, Dokki, 12622 Giza, Egypt
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13
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Current situation of biofuel production and its enhancement by CRISPR/Cas9-mediated genome engineering of microbial cells. Microbiol Res 2019; 219:1-11. [DOI: 10.1016/j.micres.2018.10.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 10/10/2018] [Accepted: 10/30/2018] [Indexed: 12/26/2022]
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14
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Conway JM, Crosby JR, Hren AP, Southerland RT, Lee LL, Lunin VV, Alahuhta P, Himmel ME, Bomble YJ, Adams MWW, Kelly RM. Novel multidomain, multifunctional glycoside hydrolases from highly lignocellulolytic
Caldicellulosiruptor
species. AIChE J 2018. [DOI: 10.1002/aic.16354] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Jonathan M. Conway
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
| | - James R. Crosby
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
| | - Andrew P. Hren
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
| | - Robert T. Southerland
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
| | - Laura L. Lee
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
| | | | - Petri Alahuhta
- Biosciences CenterNational Renewable Energy LaboratoryGoldenCO80401
| | | | | | - Michael W. W. Adams
- Dept. of Biochemistry and Molecular BiologyUniversity of GeorgiaAthensGA30602
| | - Robert M. Kelly
- Dept. of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleighNC27695
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15
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Valls C, Pastor FJ, Vidal T, Roncero MB, Díaz P, Martínez J, Valenzuela SV. Antioxidant activity of xylooligosaccharides produced from glucuronoxylan by Xyn10A and Xyn30D xylanases and eucalyptus autohydrolysates. Carbohydr Polym 2018; 194:43-50. [DOI: 10.1016/j.carbpol.2018.04.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 01/07/2023]
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16
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Low-resolution SAXS and comparative modeling based structure analysis of endo-β-1,4-xylanase a family 10 glycoside hydrolase from Pseudopedobacter saltans comb. nov. Int J Biol Macromol 2018; 112:1104-1114. [DOI: 10.1016/j.ijbiomac.2018.02.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/05/2018] [Accepted: 02/07/2018] [Indexed: 11/20/2022]
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17
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Xu T, Huang X, Li Z, Ki Lin CS, Li S. Enhanced Purification Efficiency and Thermal Tolerance of Thermoanaerobacterium aotearoense β-Xylosidase through Aggregation Triggered by Short Peptides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:4182-4188. [PMID: 29633613 DOI: 10.1021/acs.jafc.8b00551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
To simplify purification and improve heat tolerance of a thermostable β-xylosidase (ThXylC), a short ELK16 peptide was attached to its C-terminus, which is designated as ThXylC-ELK. Wild-type ThXylC was normally expressed in soluble form. However, ThXylC-ELK assembled into aggregates with 98.6% of total β-xylosidase activity. After simple centrifugation and buffer washing, the ThXylC-ELK particles were collected with 92.57% activity recovery and 95% purity, respectively. Meanwhile, the wild-type ThXylC recovery yield was less than 55% after heat inactivation, affinity and desalting chromatography followed by HRV 3C protease cleavage purification. Catalytic efficiency ( Kcat/ Km) was increased from 21.31 mM-1 s-1 for ThXylC to 32.19 mM-1 s-1 for ThXylC-ELK accompanied by a small increase in Km value. Heat tolerance of ThXylC-ELK at high temperatures was also increased. The ELK16 peptide attachment resulted in 6.2-fold increase of half-life at 65 °C. Released reducing sugars were raised 1.3-fold during sugar cane bagasse hydrolysis when ThXylC-ELK was supplemented into the combination of XynAΔSLH and Cellic CTec2.
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Affiliation(s)
- Tianwang Xu
- Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering , South China University of Technology , Guangzhou 510006 , China
| | - Xiongliang Huang
- Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering , South China University of Technology , Guangzhou 510006 , China
| | - Zhe Li
- Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering , South China University of Technology , Guangzhou 510006 , China
| | - Carol Sze Ki Lin
- School of Energy and Environment , City University of Hong Kong , Tat Chee Avenue , Kowloon , Hong Kong
| | - Shuang Li
- Provincial Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering , South China University of Technology , Guangzhou 510006 , China
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18
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Site-directed mutagenesis of GH10 xylanase A from Penicillium canescens for determining factors affecting the enzyme thermostability. Int J Biol Macromol 2017. [DOI: 10.1016/j.ijbiomac.2017.06.079] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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19
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Qiu H, Li Z, Wang H, Zhang H, Li S, Luo X, Song Y, Wang N, He H, Zhou H, Ma W, Zhang T. Molecular and biochemical characterization of a novel cold-active and metal ion-tolerant GH10 xylanase from frozen soil. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2017.1359667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Haiyan Qiu
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Zhongyuan Li
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
- Key laboratory of Feed Biotechnology, The Ministry of Agriculture of the People's Republic of China, Beijing, 100081, P.R. China
| | - Hui Wang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Haiying Zhang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Shuang Li
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Xuegang Luo
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Yajian Song
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Nan Wang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Hongpeng He
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Hao Zhou
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Wenjian Ma
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
| | - Tongcun Zhang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin, P.R. China
- Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, P.R. China
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20
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Zhang Y, An J, Yang G, Zhang X, Xie Y, Chen L, Feng Y. Structure features of GH10 xylanase from Caldicellulosiruptor bescii: implication for its thermophilic adaption and substrate binding preference. Acta Biochim Biophys Sin (Shanghai) 2016; 48:948-957. [PMID: 27563004 DOI: 10.1093/abbs/gmw086] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/27/2016] [Indexed: 12/11/2022] Open
Abstract
Caldicellulosiruptor bescii is the most thermophilic cellulolytic species of organisms known to date. In our previous study, GH10 xylanase CbXyn10B from C. bescii displayed outstanding hydrolytic activity toward various xylans at high temperatures. To understand the structural basis for this protein's catalysis and thermostability, we solved the crystal structures of CbXyn10B and its complexes with xylooligosaccharides. These structural models were used to guide comparison with its mesophilic counterpart PbXyn10B. A distinctive structural feature is that thermophilic CbXyn10B presents a relatively stable interaction between the extended loops L7 and L8 in the catalytic cleft by an extensive hydrogen bonding network, which is mediated by Lys306, Arg314 and three well-ordered water molecules. Moreover, a unique aromatic cluster consisting of Try17, Phe20, Phe21, and Phe337 may enhance the interaction between the N- and C- terminus. Targeted mutagenesis demonstrated that these interactions substantially contribute to enzyme stabilization, as indicated by a considerable decrease in the melting temperature (Tm) of CbXyn10B by substituting critical residues with Ala. Therefore, it was shown that not only the aromatic interaction connecting protein termini but also the extensive hydrogen bonding network formed between surface loops could restrict the local structural flexibility and contribute significantly to the overall stability of enzymes. Furthermore, the xylooligosaccharides were found to tightly bind to the glycone subsites of xylanase, indicating higher affinities at these subsites and reflecting its substrate binding preference. Our results suggest that CbXyn10B is stabilized with distinct rigidity at the catalytic cleft as well as the terminal regions, which provides insights into the evolutionary strategy for accommodating the functional needs of GH10 enzymes to high temperature.
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Affiliation(s)
- Yong Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jiao An
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Guangyu Yang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaofei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yuan Xie
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liuqing Chen
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yan Feng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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21
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The Glycoside Hydrolase Family 8 Reducing-End Xylose-Releasing Exo-oligoxylanase Rex8A from Paenibacillus barcinonensis BP-23 Is Active on Branched Xylooligosaccharides. Appl Environ Microbiol 2016; 82:5116-24. [PMID: 27316951 DOI: 10.1128/aem.01329-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/27/2016] [Indexed: 01/06/2023] Open
Abstract
UNLABELLED A GH8 family enzyme involved in xylan depolymerization has been characterized. The enzyme, Rex8A, is a reducing-end xylose-releasing exo-oligoxylanase (Rex) that efficiently hydrolyzes xylooligosaccharides and shows minor activity on polymeric xylan. Rex8A hydrolyzes xylooligomers of 3 to 6 xylose units to xylose and xylobiose in long-term incubations. Kinetic constants of Rex8A were determined on xylotriose, showing a Km of 1.64 ± 0.03 mM and a kcat value of 118.8 s(-1) Besides linear xylooligosaccharides, the enzyme hydrolyzed decorated xylooligomers. The catalytic activity on branched xylooligosaccharides, i.e., the release of xylose from the reducing end, is a newly described trait of xylose-releasing exo-oligoxylanases, as the exo-activity on these substrates has not been reported for the few of these enzymes characterized to date. Modeling of the three-dimensional (3D) structure of Rex8A shows an (α/α)6 barrel fold where the loops connecting the α-helices contour the active site. These loops, which show high sequence diversity among GH8 enzymes, shape a catalytic cleft with a -2 subsite that can accommodate methyl-glucuronic acid decorations. The hydrolytic ability of Rex8A on branched oligomers can be crucial for the complete depolymerization of highly substituted xylans, which is indispensable to accomplish biomass deconstruction and to generate efficient catalysts. IMPORTANCE A GH8 family enzyme involved in xylan depolymerization has been characterized. The Rex8A enzyme from Paenibacillus barcinonensis is involved in depolymerization of glucuronoxylan, a major component of the lignocellulosic substrates. The study shows that Rex8A is a reducing-end xylose-releasing exo-oligoxylanase that efficiently hydrolyzes xylose from neutral and acidic xylooligosaccharides generated by the action of other xylanases also secreted by the strain. The activity of a Rex enzyme on branched xylooligosaccharides has not been described to date. This report provides original and useful information on the properties of a new example of the rarely studied Rex enzymes. Depolymerization of highly substituted xylans is crucial for biomass valorization as a platform for generation of biofuels, chemicals, and solvents.
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22
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Biochemical characterization of extra- and intracellular endoxylanse from thermophilic bacterium Caldicellulosiruptor kronotskyensis. Sci Rep 2016; 6:21672. [PMID: 26899227 PMCID: PMC4761950 DOI: 10.1038/srep21672] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/28/2016] [Indexed: 01/25/2023] Open
Abstract
Caldicellulosiruptor kronotskyensis grows on lignocellulosic biomass by the catalysis of intrinsic glycoside hydrolase, and has potential application for consolidated bioprocessing. In current study, two predicted extra- (Xyn10A) and intracellular (Xyn10B) xylanase from C. kronotskyensis were comparatively characterized. Xyn10A and Xyn10B share GH10 catalytic domain with similarity of 41%, while the former contains two tandem N-terminus CBM22s. Xyn10A showed higher hydrolytic capability than Xyn10B on both beechwood xylan (BWX) and oat spelt xylan (OSX). Truncation mutation experiments revealed the importance of CBMs for hydrolytic activity, substrate binding and thermostability of Xyn10A.While the quantity of CBM was not directly related to bind and thermostability. Although CBM was considered to be crucial for substrate binding, Xyn10B and Xyn10A as well as truncations performed similar binding affinity to insoluble substrate OSX. Analysis of point mutation revealed similar key residues, Glu493, Glu601 and Trp658 for Xyn10A and Glu139, Glu247 and Trp305 for Xyn10B. Both Xyn10A and Xyn10B exhibited hydrolytic activity on the mechanical pretreated corncob. After pre-digested by Xyn10A or Xyn10B, the micropores inthe the mechanical pretreated corncob were observed, which enhanced the accessibility for cellulase. Compared with corncob hydrolyzed with cellulase alone, enhanced hydrolytic performance of was observed after pre-digestion by Xyn10A or Xyn10B.
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23
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Kumar V, Marín-Navarro J, Shukla P. Thermostable microbial xylanases for pulp and paper industries: trends, applications and further perspectives. World J Microbiol Biotechnol 2016; 32:34. [PMID: 26754672 DOI: 10.1007/s11274-015-2005-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 12/23/2015] [Indexed: 10/22/2022]
Abstract
Xylanases are enzymes with biotechnological relevance in a number of fields, including food, feed, biofuel, and textile industries. Their most significant application is in the paper and pulp industry, where they are used as a biobleaching agent, showing clear economic and environmental advantages over chemical alternatives. Since this process requires high temperatures and alkali media, the identification of thermostable and alkali stable xylanases represents a major biotechnological goal in this field. Moreover, thermostability is a desirable property for many other applications of xylanases. The review makes an overview of xylanase producing microorganisms and their current implementation in paper biobleaching. Future perspectives are analyzed focusing in the efforts carried out to generate thermostable enzymes by means of modern biotechnological tools, including metagenomic analysis, enzyme molecular engineering and nanotechnology. Furthermore, structural and mutagenesis studies have revealed critical sites for stability of xylanases from glycoside hydrolase families GH10 and GH11, which constitute the main classes of these enzymes. The overall conclusions of these works are summarized here and provide relevant information about putative weak spots within xylanase structures to be targeted in future protein engineering approaches.
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Affiliation(s)
- Vishal Kumar
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Julia Marín-Navarro
- Instituto de Agroquímica y Tecnología de Alimentos, C.S.I.C., Av. Catedrático Agustín Escardino, 7, E6980, Paterna, Valencia, Spain
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India.
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24
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Zheng F, Huang J, Liu X, Hu H, Long L, Chen K, Ding S. N- and C-terminal truncations of a GH10 xylanase significantly increase its activity and thermostability but decrease its SDS resistance. Appl Microbiol Biotechnol 2015; 100:3555-65. [DOI: 10.1007/s00253-015-7176-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 11/09/2015] [Accepted: 11/13/2015] [Indexed: 11/28/2022]
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25
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Engineering the hydrophobic residues of a GH11 xylanase impacts its adsorption onto lignin and its thermostability. Enzyme Microb Technol 2015; 81:47-55. [DOI: 10.1016/j.enzmictec.2015.07.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 07/24/2015] [Accepted: 07/25/2015] [Indexed: 11/23/2022]
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26
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Huang X, Li Z, Du C, Wang J, Li S. Improved Expression and Characterization of a Multidomain Xylanase from Thermoanaerobacterium aotearoense SCUT27 in Bacillus subtilis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:6430-9. [PMID: 26132889 DOI: 10.1021/acs.jafc.5b01259] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A xylanase gene was cloned and characterized from Thermoanerobacterium aotearoense SCUT27, which was attested to consist of a signal peptide, one glycoside hydrolase family 10 domain, four carbohydrate binding modules, and three surface layer homology domains. The change of expression host from Escherichia coli to Bacillus subtilis resulted in a 4.1-fold increase of specific activity for the truncated XynAΔSLH. Five different versions of secretion signals in B. subtilis indicated that it was preferably routed via a Sec-dependent pathway. Purified XynAΔSLH showed a high activity of 379.8 U/mg on beechwood xylan. XynAΔSLH was optimally active at 80 °C, pH 6.5. Thin layer chromatography results showed that xylobiose and the presumed methylglucuronoxylotriose (MeGlcAXyl3) were the main products liberated from beechwood xylan catalyzed by the recombinant xylanase. All of the results suggest that XynAΔSLH is a suitable candidate for generating xylooligosaccharides from cellulosic materials for industrial uses.
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Affiliation(s)
- Xiongliang Huang
- †Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, China
| | - Zhe Li
- †Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, China
| | - Chenyu Du
- §School of Applied Sciences, The University of Huddersfield, Queensgate, Huddersfield, United Kingdom
| | - Jufang Wang
- †Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, China
| | - Shuang Li
- †Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, China
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Sainz-Polo MA, González B, Menéndez M, Pastor FIJ, Sanz-Aparicio J. Exploring Multimodularity in Plant Cell Wall Deconstruction: STRUCTURAL AND FUNCTIONAL ANALYSIS OF Xyn10C CONTAINING THE CBM22-1-CBM22-2 TANDEM. J Biol Chem 2015; 290:17116-30. [PMID: 26001782 DOI: 10.1074/jbc.m115.659300] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Indexed: 11/06/2022] Open
Abstract
Elucidating the molecular mechanisms regulating multimodularity is a challenging task. Paenibacillus barcinonensis Xyn10C is a 120-kDa modular enzyme that presents the CBM22/GH10/CBM9 architecture found in a subset of large xylanases. We report here the three-dimensional structure of the Xyn10C N-terminal region, containing the xylan-binding CBM22-1-CBM22-2 tandem (Xyn10C-XBD), which represents the first solved crystal structure of two contiguous CBM22 modules. Xyn10C-XBD is folded into two separate CBM22 modules linked by a flexible segment that endows the tandem with extraordinary plasticity. Each isolated domain has been expressed and crystallized, and their binding abilities have been investigated. Both domains contain the R(W/Y)YYE motif required for xylan binding. However, crystallographic analysis of CBM22-2 complexes shows Trp-308 as an additional binding determinant. The long loop containing Trp-308 creates a platform that possibly contributes to the recognition of precise decorations at subsite S2. CBM22-2 may thus define a subset of xylan-binding CBM22 modules directed to particular regions of the polysaccharide. Affinity electrophoresis reveals that Xyn10C-XBD binds arabinoxylans more tightly, which is more apparent when CBM22-2 is tested against highly substituted xylan. The crystal structure of the catalytic domain, also reported, shows the capacity of the active site to accommodate xylan substitutions at almost all subsites. The structural differences found at both Xyn10C-XBD domains are consistent with the isothermal titration calorimetry experiments showing two sites with different affinities in the tandem. On the basis of the distinct characteristics of CBM22, a delivery strategy of Xyn10C mediated by Xyn10C-XBD is proposed.
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Affiliation(s)
| | - Beatriz González
- From the Departamentos de Cristalografía y Biología Estructural y
| | - Margarita Menéndez
- Química Física Biólogica, Instituto de Química-Física Rocasolano, Consejo Superior de Investigaciones Científicas, Serrano 119, 28006-Madrid and
| | - F I Javier Pastor
- the Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain
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Chen CC, Ko TP, Huang JW, Guo RT. Heat- and Alkaline-Stable Xylanases: Application, Protein Structure and Engineering. CHEMBIOENG REVIEWS 2015. [DOI: 10.1002/cben.201400035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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29
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Santos CR, Hoffmam ZB, de Matos Martins VP, Zanphorlin LM, de Paula Assis LH, Honorato RV, Lopes de Oliveira PS, Ruller R, Murakami MT. Molecular mechanisms associated with xylan degradation by Xanthomonas plant pathogens. J Biol Chem 2014; 289:32186-32200. [PMID: 25266726 PMCID: PMC4231694 DOI: 10.1074/jbc.m114.605105] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 09/22/2014] [Indexed: 11/06/2022] Open
Abstract
Xanthomonas pathogens attack a variety of economically relevant plants, and their xylan CUT system (carbohydrate utilization with TonB-dependent outer membrane transporter system) contains two major xylanase-related genes, xynA and xynB, which influence biofilm formation and virulence by molecular mechanisms that are still elusive. Herein, we demonstrated that XynA is a rare reducing end xylose-releasing exo-oligoxylanase and not an endo-β-1,4-xylanase as predicted. Structural analysis revealed that an insertion in the β7-α7 loop induces dimerization and promotes a physical barrier at the +2 subsite conferring this unique mode of action within the GH10 family. A single mutation that impaired dimerization became XynA active against xylan, and high endolytic activity was achieved when this loop was tailored to match a canonical sequence of endo-β-1,4-xylanases, supporting our mechanistic model. On the other hand, the divergent XynB proved to be a classical endo-β-1,4-xylanase, despite the low sequence similarity to characterized GH10 xylanases. Interestingly, this enzyme contains a calcium ion bound nearby to the glycone-binding region, which is required for catalytic activity and structural stability. These results shed light on the molecular basis for xylan degradation by Xanthomonas and suggest how these enzymes synergistically assist infection and pathogenesis. Our findings indicate that XynB contributes to breach the plant cell wall barrier, providing nutrients and facilitating the translocation of effector molecules, whereas the exo-oligoxylanase XynA possibly participates in the suppression of oligosaccharide-induced immune responses.
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Affiliation(s)
- Camila Ramos Santos
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Zaira Bruna Hoffmam
- Bioethanol Science and Technology Laboratory, National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Vanesa Peixoto de Matos Martins
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Leticia Maria Zanphorlin
- Bioethanol Science and Technology Laboratory, National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Leandro Henrique de Paula Assis
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Rodrigo Vargas Honorato
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Paulo Sérgio Lopes de Oliveira
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Roberto Ruller
- Bioethanol Science and Technology Laboratory, National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil
| | - Mario Tyago Murakami
- Biosciences National Laboratory and National Center for Research in Energy and Materials, Campinas, São Paulo, 13083-970, Brazil.
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Expression of Aeromonas punctata ME-1 exo-xylanase X in E. coli for efficient hydrolysis of xylan to xylose. Appl Biochem Biotechnol 2014; 174:2653-62. [PMID: 25213085 DOI: 10.1007/s12010-014-1216-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 08/31/2014] [Indexed: 10/24/2022]
Abstract
exo-Xylanase X from Aeromonas punctata ME-1 was functionally expressed in Escherichia coli with a carboxy terminal His tag (6×) and a molecular mass of 39.42 kDa, which is in agreement with the prediction from its amino acid composition. The recombinant exo-xylanase reached 186 mg l(-1) after induction by isopropyl β-D-1-thiogalactopyranoside. Its optimal temperature and pH were 50 °C and 6, respectively. The enzyme showed not only an exo-xylanase activity with K m of 3.90 mg ml(-1) and V max of 12.9 U μg(-1) for hydrolysis of Remazol Brilliant Blue-xylan but also a considerable exo-glucanase activity (27.9 U mg(-1)) on P-nitrophenyl β-D-cellobioside. It hydrolyzed xylan predominantly to xylobiose, xylotriose, xylotetraose, and xylose. An enzyme mixture of exo-xylanase and endo-xylanase (50 μg ml(-1) each) yielded a larger amount (330 mg l(-1)) of xylose from beechwood xylan than the controls (270 and 150 mg l(-1)) using them alone at 100 μg ml(-1), indicating a synergistic action between the two xylanases favoring the hydrolysis of beechwood xylan to release more xylose.
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Sainz-Polo MA, Valenzuela SV, González B, Pastor FIJ, Sanz-Aparicio J. Structural analysis of glucuronoxylan-specific Xyn30D and its attached CBM35 domain gives insights into the role of modularity in specificity. J Biol Chem 2014; 289:31088-101. [PMID: 25202007 DOI: 10.1074/jbc.m114.597732] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Glucuronoxylanase Xyn30D is a modular enzyme containing a family 30 glycoside hydrolase catalytic domain and an attached carbohydrate binding module of the CBM35 family. We present here the three-dimensional structure of the full-length Xyn30D at 2.4 Å resolution. The catalytic domain folds into an (α/β)8 barrel with an associated β-structure, whereas the attached CBM35 displays a jellyroll β-sandwich including two calcium ions. Although both domains fold in an independent manner, the linker region makes polar interactions with the catalytic domain, allowing a moderate flexibility. The ancillary Xyn30D-CBM35 domain has been expressed and crystallized, and its binding abilities have been investigated by soaking experiments. Only glucuronic acid-containing ligands produced complexes, and their structures have been solved. A calcium-dependent glucuronic acid binding site shows distinctive structural features as compared with other uronic acid-specific CBM35s, because the presence of two aromatic residues delineates a wider pocket. The nonconserved Glu(129) makes a bidentate link to calcium and defines region E, previously identified as specificity hot spot. The molecular surface of Xyn30D-CBM35 shows a unique stretch of negative charge distribution extending from its binding pocket that might indicate some oriented interaction with its target substrate. The binding ability of Xyn30D-CBM35 to different xylans was analyzed by affinity gel electrophoresis. Some binding was observed with rye glucuronoarabinoxylan in presence of calcium chelating EDTA, which would indicate that Xyn30D-CBM35 might establish interaction to other components of xylan, such as arabinose decorations of glucuronoarabinoxylan. A role in depolymerization of highly substituted chemically complex xylans is proposed.
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Affiliation(s)
- M Angela Sainz-Polo
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - Susana Valeria Valenzuela
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Beatriz González
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - F I Javier Pastor
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Julia Sanz-Aparicio
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
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32
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Biochemical characterization of two thermostable xylanolytic enzymes encoded by a gene cluster of Caldicellulosiruptor owensensis. PLoS One 2014; 9:e105264. [PMID: 25127169 PMCID: PMC4134300 DOI: 10.1371/journal.pone.0105264] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 07/19/2014] [Indexed: 02/04/2023] Open
Abstract
The xylanolytic extremely thermophilic bacterium Caldicellulosiruptor owensensis provides a promising platform for xylan utilization. In the present study, two novel xylanolytic enzymes, GH10 endo-β-1,4-xylanase (Coxyn A) and GH39 β-1,4-xylosidase (Coxyl A) encoded in one gene cluster of C.owensensis were heterogeneously expressed and biochemically characterized. The optimum temperature of the two xylanlytic enzymes was 75°C, and the respective optimum pH for Coxyn A and Coxyl A was 7.0 and 5.0. The difference of Coxyn A and Coxyl A in solution was existing as monomer and homodimer respectively, it was also observed in predicted secondary structure. Under optimum condition, the catalytic efficiency (kcat/Km) of Coxyn A was 366 mg ml−1 s−1 on beechwood xylan, and the catalytic efficiency (kcat/Km) of Coxyl A was 2253 mM−1 s−1 on pNP-β-D-xylopyranoside. Coxyn A degraded xylan to oligosaccharides, which were converted to monomer by Coxyl A. The two intracellular enzymes might be responsible for xylooligosaccharides utilization in C.owensensis, also provide a potential way for xylan degradation in vitro.
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A thermo-halo-tolerant and proteinase-resistant endoxylanase from Bacillus sp. HJ14. Folia Microbiol (Praha) 2014; 59:423-31. [DOI: 10.1007/s12223-014-0316-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 03/27/2014] [Indexed: 12/13/2022]
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34
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Valenzuela SV, Diaz P, Pastor FIJ. Xyn11E from Paenibacillus barcinonensis BP-23: a LppX-chaperone-dependent xylanase with potential for upgrading paper pulps. Appl Microbiol Biotechnol 2014; 98:5949-57. [DOI: 10.1007/s00253-014-5565-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/20/2013] [Accepted: 01/21/2014] [Indexed: 12/21/2022]
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35
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Xie Y, An J, Yang G, Wu G, Zhang Y, Cui L, Feng Y. Enhanced enzyme kinetic stability by increasing rigidity within the active site. J Biol Chem 2014; 289:7994-8006. [PMID: 24448805 DOI: 10.1074/jbc.m113.536045] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Enzyme stability is an important issue for protein engineers. Understanding how rigidity in the active site affects protein kinetic stability will provide new insight into enzyme stabilization. In this study, we demonstrated enhanced kinetic stability of Candida antarctica lipase B (CalB) by mutating the structurally flexible residues within the active site. Six residues within 10 Å of the catalytic Ser(105) residue with a high B factor were selected for iterative saturation mutagenesis. After screening 2200 colonies, we obtained the D223G/L278M mutant, which exhibited a 13-fold increase in half-life at 48 °C and a 12 °C higher T50(15), the temperature at which enzyme activity is reduced to 50% after a 15-min heat treatment. Further characterization showed that global unfolding resistance against both thermal and chemical denaturation also improved. Analysis of the crystal structures of wild-type CalB and the D223G/L278M mutant revealed that the latter formed an extra main chain hydrogen bond network with seven structurally coupled residues within the flexible α10 helix that are primarily involved in forming the active site. Further investigation of the relative B factor profile and molecular dynamics simulation confirmed that the enhanced rigidity decreased fluctuation of the active site residues at high temperature. These results indicate that enhancing the rigidity of the flexible segment within the active site may provide an efficient method for improving enzyme kinetic stability.
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Affiliation(s)
- Yuan Xie
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China and
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Song HY, Lim HK, Kim DR, Lee KI, Hwang IT. A new bi-modular endo-β-1,4-xylanase KRICT PX-3 from whole genome sequence of Paenibacillus terrae HPL-003. Enzyme Microb Technol 2014; 54:1-7. [DOI: 10.1016/j.enzmictec.2013.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 09/04/2013] [Accepted: 09/05/2013] [Indexed: 10/26/2022]
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37
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Ghatge SS, Telke AA, Kang SH, Arulalapperumal V, Lee KW, Govindwar SP, Um Y, Oh DB, Shin HD, Kim SW. Characterization of modular bifunctional processive endoglucanase Cel5 from Hahella chejuensis KCTC 2396. Appl Microbiol Biotechnol 2013; 98:4421-35. [PMID: 24343767 DOI: 10.1007/s00253-013-5446-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/28/2013] [Accepted: 11/28/2013] [Indexed: 11/29/2022]
Abstract
Cel5 from marine Hahella chejuensis is composed of glycoside hydrolase family-5 (GH5) catalytic domain (CD) and two carbohydrate binding modules (CBM6-2). The enzyme was expressed in Escherichia coli and purified to homogeneity. The optimum endoglucanase and xylanase activities of recombinant Cel5 were observed at 65 °C, pH 6.5 and 55 °C, pH 5.5, respectively. It exhibited K m of 1.8 and 7.1 mg/ml for carboxymethyl cellulose and birchwood xylan, respectively. The addition of Ca(2+) greatly improved thermostability and endoglucanase activity of Cel5. The Cel5 retained 90 % of its endoglucanase activity after 24 h incubation in presence of 5 M concentration of NaCl. Recombinant Cel5 showed production of cellobiose after hydrolysis of cellulosic substrates (soluble/insoluble) and methylglucuronic acid substituted xylooligosaccharides after hydrolysis of glucuronoxylans by endo-wise cleavage. These results indicated that Cel5 as bifunctional enzyme having both processive endoglucanase and xylanase activities. The multidomain structure of Cel5 is clearly distinguished from the GH5 bifunctional glycoside hydrolases characterized to date, which are single domain enzymes. Sequence analysis and homology modeling suggested presence of two conserved binding sites with different substrate specificities in CBM6-2 and a single catalytic site in CD. Residues Glu132 and Glu219 were identified as key catalytic amino acids by sequence alignment and further verified by using site directed mutagenesis. CBM6-2 plays vital role in catalytic activity and thermostability of Cel5. The bifunctional activities and multiple substrate specificities of Cel5 can be utilized for efficient hydrolysis of cellulose and hemicellulose into soluble sugars.
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Affiliation(s)
- Sunil Subhash Ghatge
- Division of Applied Life Sciences (BK21), PMBBRC, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
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38
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Improving catalytic efficiency of endo-β-1, 4-xylanase from Geobacillus stearothermophilus by directed evolution and H179 saturation mutagenesis. J Biotechnol 2013; 168:341-7. [DOI: 10.1016/j.jbiotec.2013.09.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/15/2013] [Accepted: 09/18/2013] [Indexed: 11/19/2022]
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39
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Modular glucuronoxylan-specific xylanase with a family CBM35 carbohydrate-binding module. Appl Environ Microbiol 2012; 78:3923-31. [PMID: 22447606 DOI: 10.1128/aem.07932-11] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xyn30D from the xylanolytic strain Paenibacillus barcinonensis has been identified and characterized. The enzyme shows a modular structure comprising a catalytic module family 30 (GH30) and a carbohydrate-binding module family 35 (CBM35). Like GH30 xylanases, recombinant Xyn30D efficiently hydrolyzed glucuronoxylans and methyl-glucuronic acid branched xylooligosaccharides but showed no catalytic activity on arabinose-substituted xylans. Kinetic parameters of Xyn30D were determined on beechwood xylan, showing a K(m) of 14.72 mg/ml and a k(cat) value of 1,510 min(-1). The multidomain structure of Xyn30D clearly distinguishes it from the GH30 xylanases characterized to date, which are single-domain enzymes. The modules of the enzyme were individually expressed in a recombinant host and characterized. The isolated GH30 catalytic module showed specific activity, mode of action on xylan, and kinetic parameters that were similar to those of the full-length enzyme. Computer modeling of the three-dimensional structure of Xyn30D showed that the catalytic module is comprised of a common (β/α)(8) barrel linked to a side-associated β-structure. Several derivatives of the catalytic module with decreasing deletions of this associated structure were constructed. None of them showed catalytic activity, indicating the importance of the side β-structure in the catalysis of Xyn30D. Binding properties of the isolated carbohydrate-binding module were analyzed by affinity gel electrophoresis, which showed that the CBM35 of the enzyme binds to soluble glucuronoxylans and arabinoxylans. Analysis by isothermal titration calorimetry showed that CBM35 binds to glucuronic acid and requires calcium ions for binding. Occurrence of a CBM35 in a glucuronoxylan-specific xylanase is a differential trait of the enzyme characterized.
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40
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Kim DY, Han MK, Oh HW, Bae KS, Jeong TS, Kim SU, Shin DH, Kim IH, Rhee YH, Son KH, Park HY. Novel intracellular GH10 xylanase from Cohnella laeviribosi HY-21: biocatalytic properties and alterations of substrate specificities by site-directed mutagenesis of Trp residues. BIORESOURCE TECHNOLOGY 2010; 101:8814-8821. [PMID: 20615688 DOI: 10.1016/j.biortech.2010.06.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 05/15/2010] [Accepted: 06/03/2010] [Indexed: 05/29/2023]
Abstract
The novel intracellular GH10 xylanase (iXylC) gene (1023-bp) of Cohnella laeviribosi HY-21 encoded a protein consisting of 340 amino acids with a deduced molecular mass of 39,330Da and a calculated pI of 5.81. The primary structure of iXylC was 70% identical to that of Geobacillus sp. GH10 enzyme (GenBank accession number: EDV78425). Xylanolytic activity of the His-tagged iXylC overproduced in Escherichiacoli BL21 was stimulated by 2.2-fold in the presence of 0.5% non-ionic detergents. iXylC produced a mixture of xylooligosaccharides (xylobiose to xylooctaose) from xylotriose and xylotetraose used as the hydrolytic substrate. In addition, it exhibited considerable cleavage activities for p-nitrophenylxylopyranoside (PNP-xylopyranoside) and PNP-cellobioside, indicating that iXylC is a unique GH10 enzyme. The hydrolytic activity (57.8IUmL(-1)) of iXylC toward PNP-xylopyranoside increased to 8.3-fold by W217A and W315A mutations, while mutations of W133A, W295A, and W303A abolished the hydrolytic activity of the enzyme.
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Affiliation(s)
- Do Young Kim
- Industrial Bio-materials Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea
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Characterization of a family GH5 xylanase with activity on neutral oligosaccharides and evaluation as a pulp bleaching aid. Appl Environ Microbiol 2010; 76:6290-4. [PMID: 20656870 DOI: 10.1128/aem.00871-10] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new bacterial xylanase belonging to family 5 of glycosyl hydrolases was identified and characterized. The xylanase, Xyn5B from Bacillus sp. strain BP-7, was active on neutral, nonsubstituted xylooligosaccharides, showing a clear difference from other GH5 xylanases characterized to date that show a requirement for methyl-glucuronic acid side chains for catalysis. The enzyme was evaluated on Eucalyptus kraft pulp, showing its effectiveness as a bleaching aid.
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