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Wang X, Li A, Li X, Cui H. Empowering Protein Engineering through Recombination of Beneficial Substitutions. Chemistry 2024; 30:e202303889. [PMID: 38288640 DOI: 10.1002/chem.202303889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Indexed: 02/24/2024]
Abstract
Directed evolution stands as a seminal technology for generating novel protein functionalities, a cornerstone in biocatalysis, metabolic engineering, and synthetic biology. Today, with the development of various mutagenesis methods and advanced analytical machines, the challenge of diversity generation and high-throughput screening platforms is largely solved, and one of the remaining challenges is: how to empower the potential of single beneficial substitutions with recombination to achieve the epistatic effect. This review overviews experimental and computer-assisted recombination methods in protein engineering campaigns. In addition, integrated and machine learning-guided strategies were highlighted to discuss how these recombination approaches contribute to generating the screening library with better diversity, coverage, and size. A decision tree was finally summarized to guide the further selection of proper recombination strategies in practice, which was beneficial for accelerating protein engineering.
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Affiliation(s)
- Xinyue Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Anni Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Haiyang Cui
- School of Life Sciences, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
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2
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Wang X, Sheng Y, Cui H, Qiao J, Song Y, Li X, Huang H. Corner Engineering: Tailoring Enzymes for Enhanced Resistance and Thermostability in Deep Eutectic Solvents. Angew Chem Int Ed Engl 2024; 63:e202315125. [PMID: 38010210 DOI: 10.1002/anie.202315125] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023]
Abstract
Deep eutectic solvents (DESs), heralded for their synthesis simplicity, economic viability, and reduced volatility and flammability, have found increasing application in biocatalysis. However, challenges persist due to a frequent diminution in enzyme activity and stability. Herein, we developed a general protein engineering strategy, termed corner engineering, to acquire DES-resistant and thermostable enzymes via precise tailoring of the transition region in enzyme structure. Employing Bacillus subtilis lipase A (BSLA) as a model, we delineated the engineering process, yielding five multi-DESs resistant variants with highly improved thermostability, such as K88E/N89 K exhibited up to a 10.0-fold catalytic efficiency (kcat /KM ) increase in 30 % (v/v) choline chloride (ChCl): acetamide and 4.1-fold in 95 % (v/v) ChCl: ethylene glycol accompanying 6.7-fold thermal resistance improvement than wild type at ≈50 °C. The generality of the optimized approach was validated by two extra industrial enzymes, endo-β-1,4-glucanase PvCel5A (used for biofuel production) and esterase Bs2Est (used for plastics degradation). The molecular investigations revealed that increased water molecules at substrate binding cleft and finetuned helix formation at the corner region are two dominant determinants governing elevated resistance and thermostability. This study, coupling corner engineering with obtained molecular insights, illuminates enzyme-DES interaction patterns and fosters the rational design of more DES-resistant and thermostable enzymes in biocatalysis and biotransformation.
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Affiliation(s)
- Xinyue Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Yijie Sheng
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Haiyang Cui
- RWTH Aachen University, Templergraben 55, 52062, Aachen, Germany
- Current address: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL 61801, USA
| | - Jie Qiao
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Yibo Song
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - He Huang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
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Shishparenok AN, Gladilina YA, Zhdanov DD. Engineering and Expression Strategies for Optimization of L-Asparaginase Development and Production. Int J Mol Sci 2023; 24:15220. [PMID: 37894901 PMCID: PMC10607044 DOI: 10.3390/ijms242015220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Genetic engineering for heterologous expression has advanced in recent years. Model systems such as Escherichia coli, Bacillus subtilis and Pichia pastoris are often used as host microorganisms for the enzymatic production of L-asparaginase, an enzyme widely used in the clinic for the treatment of leukemia and in bakeries for the reduction of acrylamide. Newly developed recombinant L-asparaginase (L-ASNase) may have a low affinity for asparagine, reduced catalytic activity, low stability, and increased glutaminase activity or immunogenicity. Some successful commercial preparations of L-ASNase are now available. Therefore, obtaining novel L-ASNases with improved properties suitable for food or clinical applications remains a challenge. The combination of rational design and/or directed evolution and heterologous expression has been used to create enzymes with desired characteristics. Computer design, combined with other methods, could make it possible to generate mutant libraries of novel L-ASNases without costly and time-consuming efforts. In this review, we summarize the strategies and approaches for obtaining and developing L-ASNase with improved properties.
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Affiliation(s)
- Anastasiya N. Shishparenok
- Laboratory of Medical Biotechnology, Institute of Biomedical Chemistry, Pogodinskaya St. 10/8, 119121 Moscow, Russia; (A.N.S.); (Y.A.G.)
| | - Yulia A. Gladilina
- Laboratory of Medical Biotechnology, Institute of Biomedical Chemistry, Pogodinskaya St. 10/8, 119121 Moscow, Russia; (A.N.S.); (Y.A.G.)
| | - Dmitry D. Zhdanov
- Laboratory of Medical Biotechnology, Institute of Biomedical Chemistry, Pogodinskaya St. 10/8, 119121 Moscow, Russia; (A.N.S.); (Y.A.G.)
- Department of Biochemistry, Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University), Miklukho—Maklaya St. 6, 117198 Moscow, Russia
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Dumina M, Zhdanov D, Zhgun A, Pokrovskaya M, Aleksandrova S, Veselovsky A, El’darov M. Enhancing the Catalytic Activity of Thermo-Asparaginase from Thermococcus sibiricus by a Double Mesophilic-like Mutation in the Substrate-Binding Region. Int J Mol Sci 2023; 24:9632. [PMID: 37298582 PMCID: PMC10253665 DOI: 10.3390/ijms24119632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/27/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
L-asparaginases (L-ASNases) of microbial origin are the mainstay of blood cancer treatment. Numerous attempts have been performed for genetic improvement of the main properties of these enzymes. The substrate-binding Ser residue is highly conserved in L-ASNases regardless of their origin or type. However, the residues adjacent to the substrate-binding Ser differ between mesophilic and thermophilic L-ASNases. Based on our suggestion that the triad, including substrate-binding Ser, either GSQ for meso-ASNase or DST for thermo-ASNase, is tuned for efficient substrate binding, we constructed a double mutant of thermophilic L-ASNase from Thermococcus sibiricus (TsA) with a mesophilic-like GSQ combination. In this study, the conjoint substitution of two residues adjacent to the substrate-binding Ser55 resulted in a significant increase in the activity of the double mutant, reaching 240% of the wild-type enzyme activity at the optimum temperature of 90 °C. The mesophilic-like GSQ combination in the rigid structure of the thermophilic L-ASNase appears to be more efficient in balancing substrate binding and conformational flexibility of the enzyme. Along with increased activity, the TsA D54G/T56Q double mutant exhibited enhanced cytotoxic activity against cancer cell lines with IC90 values from 2.8- to 7.4-fold lower than that of the wild-type enzyme.
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Affiliation(s)
- Maria Dumina
- Federal Research Center “Fundamentals of Biotechnology” of the Russian Academy of Sciences, 117312 Moscow, Russia; (D.Z.); (A.Z.)
| | - Dmitry Zhdanov
- Federal Research Center “Fundamentals of Biotechnology” of the Russian Academy of Sciences, 117312 Moscow, Russia; (D.Z.); (A.Z.)
- Institute of Biomedical Chemistry, 119121 Moscow, Russia (A.V.)
| | - Alexander Zhgun
- Federal Research Center “Fundamentals of Biotechnology” of the Russian Academy of Sciences, 117312 Moscow, Russia; (D.Z.); (A.Z.)
| | | | | | | | - Michael El’darov
- Federal Research Center “Fundamentals of Biotechnology” of the Russian Academy of Sciences, 117312 Moscow, Russia; (D.Z.); (A.Z.)
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Wang N, Peng H, Yang C, Guo W, Wang M, Li G, Liu D. Metabolic Engineering of Model Microorganisms for the Production of Xanthophyll. Microorganisms 2023; 11:1252. [PMID: 37317226 PMCID: PMC10223009 DOI: 10.3390/microorganisms11051252] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/19/2023] [Accepted: 05/06/2023] [Indexed: 06/16/2023] Open
Abstract
Xanthophyll is an oxidated version of carotenoid. It presents significant value to the pharmaceutical, food, and cosmetic industries due to its specific antioxidant activity and variety of colors. Chemical processing and conventional extraction from natural organisms are still the main sources of xanthophyll. However, the current industrial production model can no longer meet the demand for human health care, reducing petrochemical energy consumption and green sustainable development. With the swift development of genetic metabolic engineering, xanthophyll synthesis by the metabolic engineering of model microorganisms shows great application potential. At present, compared to carotenes such as lycopene and β-carotene, xanthophyll has a relatively low production in engineering microorganisms due to its stronger inherent antioxidation, relatively high polarity, and longer metabolic pathway. This review comprehensively summarized the progress in xanthophyll synthesis by the metabolic engineering of model microorganisms, described strategies to improve xanthophyll production in detail, and proposed the current challenges and future efforts needed to build commercialized xanthophyll-producing microorganisms.
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Affiliation(s)
| | | | | | | | | | | | - Dehu Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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Spirov AV, Myasnikova EM. Problem of Domain/Building Block Preservation in the Evolution of Biological Macromolecules and Evolutionary Computation. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2023; 20:1345-1362. [PMID: 35594219 DOI: 10.1109/tcbb.2022.3175908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Structurally and functionally isolated domains in biological macromolecular evolution, both natural and artificial, are largely similar to "schemata", building blocks (BBs), in evolutionary computation (EC). The problem of preserving in subsequent evolutionary searches the already found domains / BBs is well known and quite relevant in biology as well as in EC. Both biology and EC are seeing parallel and independent development of several approaches to identifying and preserving previously identified domains / BBs. First, we notice the similarity of DNA shuffling methods in synthetic biology and multi-parent recombination algorithms in EC. Furthermore, approaches to computer identification of domains in proteins that are being developed in biology can be aligned with BB identification methods in EC. Finally, approaches to chimeric protein libraries optimization in biology can be compared to evolutionary search methods based on probabilistic models in EC. We propose to validate the prospects of mutual exchange of ideas and transfer of algorithms and approaches between evolutionary systems biology and EC in these three principal directions. A crucial aim of this transfer is the design of new advanced experimental techniques capable of solving more complex problems of in vitro evolution.
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Thermostability Improvement of L-Asparaginase from Acinetobacter soli via Consensus-Designed Cysteine Residue Substitution. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196670. [PMID: 36235209 PMCID: PMC9572581 DOI: 10.3390/molecules27196670] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 09/30/2022] [Accepted: 10/05/2022] [Indexed: 11/05/2022]
Abstract
To extend the application range of L-asparaginase in food pre-processing, the thermostability improvement of the enzyme is essential. Herein, two non-conserved cysteine residues with easily oxidized free sulfhydryl groups, Cys8 and Cys283, of Acinetobacter soli L-asparaginase (AsA) were screened out via consensus design. After saturation mutagenesis and combinatorial mutation, the mutant C8Y/C283Q with highly improved thermostability was obtained with a half-life of 361.6 min at 40 °C, an over 34-fold increase compared with that of the wild-type. Its melting temperature (Tm) value reaches 62.3 °C, which is 7.1 °C higher than that of the wild-type. Molecular dynamics simulation and structure analysis revealed the formation of new hydrogen bonds of Gln283 and the aromatic interaction of Tyr8 formed with adjacent residues, resulting in enhanced thermostability. The improvement in the thermostability of L-asparaginase could efficiently enhance its effect on acrylamide inhibition; the contents of acrylamide in potato chips were efficiently reduced by 86.50% after a mutant C8Y/C283Q treatment, which was significantly higher than the 59.05% reduction after the AsA wild-type treatment. In addition, the investigation of the mechanism behind the enhanced thermostability of AsA could further direct the modification of L-asparaginases for expanding their clinical and industrial applications.
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Tripathi A, Dutta Dubey K. Combined MD and QM/MM Calculations Reveal Allostery-Driven Promiscuity in Dipeptide Epimerases of Enolase Family. Chem Asian J 2022; 17:e202200528. [PMID: 35722826 DOI: 10.1002/asia.202200528] [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: 05/23/2022] [Revised: 06/19/2022] [Indexed: 11/10/2022]
Abstract
The adaptability of the active site to amplify the secondary function is supposed to be the fundamental cause of the promiscuity and the evolution of new functions in enzymes. In most cases, mutations occur close to the active site and/or in the catalytic site to change the active site plasticity to accommodate the non-native substrate. In the present study, using MD simulations and hybrid QM/MM calculations, we have shown a way to enhance the promiscuity, i. e., the allostery-driven promiscuity. Using a case study of the AEE enzyme where the capping loop recognizes the substrate, herein, we show that a single site mutation (D321G) far from the capping loop can induce a large conformational change in the capping loop to recognize different substrates for different functions. The QM/MM calculations for the WT and mutated enzyme provide a first validation of the mechanism of 1,1-proton transfer and dehydration by the AEE enzyme. Since AEE epimerase possesses a highly conserved TIM-barrel fold, we believe that our study provides a crucial lead to understanding the mechanism of emergence of secondary function which can be useful to repurpose ancient enzymes for modern usage.
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Affiliation(s)
- Ankita Tripathi
- Department of Chemistry, School of Natural Science, Shiv Nadar University Delhi-NCR, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh, 201314, India
| | - Kshatresh Dutta Dubey
- Department of Chemistry, School of Natural Science, Shiv Nadar University Delhi-NCR, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh, 201314, India.,Center for Informatics, Department of Chemistry, School of Natural Science, Shiv Nadar University Delhi-NCR, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh, 201314, India
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Yu Z, Yu H, Xu J, Wang Z, Wang Z, Kang T, Chen K, Pu Z, Wu J, Yang LR, Xu G. Enhancing Thermostability of Lipase from Pseudomonas alcaligenes for producing L-menthol by the CREATE Strategy. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00082b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Lipase from Pseudomonas alcaligenes (PaL) catalyzes the hydrolysis of racemic menthol propionate to produce L-menthol, one of the most important flavoring agents in food, cosmetics and pharmaceuticals industries. However,...
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10
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Ward EM, Kizer ME, Imperiali B. Strategies and Tactics for the Development of Selective Glycan-Binding Proteins. ACS Chem Biol 2021; 16:1795-1813. [PMID: 33497192 PMCID: PMC9200409 DOI: 10.1021/acschembio.0c00880] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The influences of glycans impact all biological processes, disease states, and pathogenic interactions. Glycan-binding proteins (GBPs), such as lectins, are decisive tools for interrogating glycan structure and function because of their ease of use and ability to selectively bind defined carbohydrate epitopes and glycosidic linkages. GBP reagents are prominent tools for basic research, clinical diagnostics, therapeutics, and biotechnological applications. However, the study of glycans is hindered by the lack of specific and selective protein reagents to cover the massive diversity of carbohydrate structures that exist in nature. In addition, existing GBP reagents often suffer from low affinity or broad specificity, complicating data interpretation. There have been numerous efforts to expand the GBP toolkit beyond those identified from natural sources through protein engineering, to improve the properties of existing GBPs or to engineer novel specificities and potential applications. This review details the current scope of proteins that bind carbohydrates and the engineering methods that have been applied to enhance the affinity, selectivity, and specificity of binders.
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Affiliation(s)
- Elizabeth M. Ward
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Microbiology Graduate Program, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
| | - Megan E. Kizer
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
| | - Barbara Imperiali
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
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Pagar AD, Patil MD, Flood DT, Yoo TH, Dawson PE, Yun H. Recent Advances in Biocatalysis with Chemical Modification and Expanded Amino Acid Alphabet. Chem Rev 2021; 121:6173-6245. [PMID: 33886302 DOI: 10.1021/acs.chemrev.0c01201] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The two main strategies for enzyme engineering, directed evolution and rational design, have found widespread applications in improving the intrinsic activities of proteins. Although numerous advances have been achieved using these ground-breaking methods, the limited chemical diversity of the biopolymers, restricted to the 20 canonical amino acids, hampers creation of novel enzymes that Nature has never made thus far. To address this, much research has been devoted to expanding the protein sequence space via chemical modifications and/or incorporation of noncanonical amino acids (ncAAs). This review provides a balanced discussion and critical evaluation of the applications, recent advances, and technical breakthroughs in biocatalysis for three approaches: (i) chemical modification of cAAs, (ii) incorporation of ncAAs, and (iii) chemical modification of incorporated ncAAs. Furthermore, the applications of these approaches and the result on the functional properties and mechanistic study of the enzymes are extensively reviewed. We also discuss the design of artificial enzymes and directed evolution strategies for enzymes with ncAAs incorporated. Finally, we discuss the current challenges and future perspectives for biocatalysis using the expanded amino acid alphabet.
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Affiliation(s)
- Amol D Pagar
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Mahesh D Patil
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Dillon T Flood
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Tae Hyeon Yoo
- Department of Molecular Science and Technology, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon 16499, Korea
| | - Philip E Dawson
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Hyungdon Yun
- Department of Systems Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
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Suchsland R, Appel B, Virta P, Müller S. Synthesis of fully protected trinucleotide building blocks on a disulphide-linked soluble support. RSC Adv 2021; 11:3892-3896. [PMID: 35424330 PMCID: PMC8694130 DOI: 10.1039/d0ra10941j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 01/12/2021] [Indexed: 11/30/2022] Open
Abstract
In recent years, preparation of fully protected trinucleotide phosphoramidites as synthons for the codon-based synthesis of gene libraries as well as for the assembly of oligonucleotides from blockmers has gained much attention. We here describe the preparation of such trinucleotide synthons on a soluble support using a disulphide linker. Fully protected trinucleotides are synthesized on a tetrapodal soluble support using a disulphide linkage that upon reductive cleavage allows release of the trinucleotide with free 3′-OH group for further conversion to a phosphoramidite.![]()
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Affiliation(s)
- Ruth Suchsland
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
| | - Bettina Appel
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
| | - Pasi Virta
- University of Turku
- Department of Chemistry
- 20014 Turku
- Finland
| | - Sabine Müller
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
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Chen LZ, Huang SL, Hou J, Guo XP, Wang FS, Sheng JZ. Cell-based and cell-free biocatalysis for the production of D-glucaric acid. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:203. [PMID: 33303009 PMCID: PMC7731778 DOI: 10.1186/s13068-020-01847-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 12/02/2020] [Indexed: 05/17/2023]
Abstract
D-Glucaric acid (GA) is a value-added chemical produced from biomass, and has potential applications as a versatile platform chemical, food additive, metal sequestering agent, and therapeutic agent. Marketed GA is currently produced chemically, but increasing demand is driving the search for eco-friendlier and more efficient production approaches. Cell-based production of GA represents an alternative strategy for GA production. A series of synthetic pathways for GA have been ported into Escherichia coli, Saccharomyces cerevisiae and Pichia pastoris, respectively, and these engineered cells show the ability to synthesize GA de novo. Optimization of the GA metabolic pathways in host cells has leapt forward, and the titer and yield have increased rapidly. Meanwhile, cell-free multi-enzyme catalysis, in which the desired pathway is constructed in vitro from enzymes and cofactors involved in GA biosynthesis, has also realized efficient GA bioconversion. This review presents an overview of studies of the development of cell-based GA production, followed by a brief discussion of potential applications of biosensors that respond to GA in these biosynthesis routes.
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Affiliation(s)
- Lu-Zhou Chen
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
| | - Si-Ling Huang
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Jin Hou
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Xue-Ping Guo
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Feng-Shan Wang
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
- National Glycoengineering Research Center, Shandong University, Jinan, 250012, China
| | - Ju-Zheng Sheng
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China.
- National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
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Mahajan D, Sengupta S, Sen S. Strategies to improve microbial lipid production: Optimization techniques. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Xiang L, Lu Y, Wang H, Wang M, Zhang G. Improving the specific activity and pH stability of xylanase XynHBN188A by directed evolution. BIORESOUR BIOPROCESS 2019. [DOI: 10.1186/s40643-019-0262-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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16
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An Efficient Approach for Two Distal Point Site-Directed Mutagenesis from Randomly Ligated PCR Products. Appl Biochem Biotechnol 2019; 189:1318-1326. [PMID: 31264104 DOI: 10.1007/s12010-019-03059-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 05/22/2019] [Indexed: 10/26/2022]
Abstract
Site-directed mutagenesis is one of the most important tools in molecular biology. The majority of the mutagenesis methods have been developed to mutate one region of target DNA in each cycle of mutagenesis, while in some cases there is a need to mutate several distal points. We used a new method to simultaneously mutate two distal points in the target DNA. Different regions of the target DNA were amplified in three separate PCR reactions. The PCR products were back-to-back and together they made the complete length of the template DNA. Mutations were introduced to PCR products by middle mutagenic primers. PCR products were mixed and ligated with random blunt ligation, and then the desired mutated DNA fragments were selected in two steps by flanking restriction enzyme digestion and size selection. Selected fragments were amplified in another PCR reaction using flanking primers and finally cloned into the plasmid vector. This mutagenesis process is simple, there is no need to use modified primers and long or difficult PCR reactions.
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Mitra S, Das A, Sen S, Mahanty B. Potential of metabolic engineering in bacterial nanosilver synthesis. World J Microbiol Biotechnol 2018; 34:138. [DOI: 10.1007/s11274-018-2522-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/20/2018] [Indexed: 10/28/2022]
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Li H, Li J, Jin R, Chen W, Liang C, Wu J, Jin JM, Tang SY. Towards the construction of high-quality mutagenesis libraries. Biotechnol Lett 2018; 40:1101-1107. [PMID: 29700725 DOI: 10.1007/s10529-018-2559-7] [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: 01/09/2018] [Accepted: 04/23/2018] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To improve the quality of mutagenesis libraries in directed evolution strategy. RESULTS In the process of library transformation, transformants which have been shown to take up more than one plasmid might constitute more than 20% of the constructed library, thereby extensively impairing the quality of the library. We propose a practical transformation method to prevent the occurrence of multiple-plasmid transformants while maintaining high transformation efficiency. A visual library model containing plasmids expressing different fluorescent proteins was used. Multiple-plasmid transformants can be reduced through optimizing plasmid DNA amount used for transformation based on the positive correlation between the occurrence frequency of multiple-plasmid transformants and the logarithmic ratio of plasmid molecules to competent cells. CONCLUSIONS This method provides a simple solution for a seemingly common but often neglected problem, and should be valuable for improving the quality of mutagenesis libraries to enhance the efficiency of directed evolution strategies.
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Affiliation(s)
- Heng Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jing Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruinan Jin
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wei Chen
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chaoning Liang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jieyuan Wu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian-Ming Jin
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, 100048, China
| | - Shuang-Yan Tang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, 100101, China.
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Taniguchi N, Murakami H. Multiple Site-Directed and Saturation Mutagenesis by the Patch Cloning Method. Methods Mol Biol 2017; 1498:339-347. [PMID: 27709586 DOI: 10.1007/978-1-4939-6472-7_22] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Constructing protein-coding genes with desired mutations is a basic step for protein engineering. Herein, we describe a multiple site-directed and saturation mutagenesis method, termed MUPAC. This method has been used to introduce multiple site-directed mutations in the green fluorescent protein gene and in the moloney murine leukemia virus reverse transcriptase gene. Moreover, this method was also successfully used to introduce randomized codons at five desired positions in the green fluorescent protein gene, and for simple DNA assembly for cloning.
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Affiliation(s)
| | - Hiroshi Murakami
- Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.
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Feng T, Yang X, Wang D, Hu X, Liao J, Pu J, Zhao X, Zhan CG, Liao F. A Practical System for High-Throughput Screening of Mutants of Bacillus fastidiosus Uricase. Appl Biochem Biotechnol 2016; 181:667-681. [DOI: 10.1007/s12010-016-2240-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 09/05/2016] [Indexed: 11/28/2022]
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Baweja M, Nain L, Kawarabayasi Y, Shukla P. Current Technological Improvements in Enzymes toward Their Biotechnological Applications. Front Microbiol 2016; 7:965. [PMID: 27379087 PMCID: PMC4909775 DOI: 10.3389/fmicb.2016.00965] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 06/03/2016] [Indexed: 01/07/2023] Open
Abstract
Enzymes from extremophiles are creating interest among researchers due to their unique properties and the enormous power of catalysis at extreme conditions. Since community demands are getting more intensified, therefore, researchers are applying various approaches viz. metagenomics to increase the database of extremophilic species. Furthermore, the innovations are being made in the naturally occurring enzymes utilizing various tools of recombinant DNA technology and protein engineering, which allows redesigning of the enzymes for its better fitment into the process. In this review, we discuss the biochemical constraints of psychrophiles during survival at the lower temperature. We summarize the current knowledge about the sources of such enzymes and their in vitro modification through mutagenesis to explore their biotechnological potential. Finally, we recap the microbial cell surface display to enhance the efficiency of the process in cost effective way.
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Affiliation(s)
- Mehak Baweja
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak India
| | - Lata Nain
- Division of Microbiology, Indian Agricultural Research Institute, New Delhi India
| | - Yutaka Kawarabayasi
- National Institute of Advanced Industrial Science and Technology, Tsukuba Japan
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak India
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Yuan M, Yang X, Li Y, Liu H, Pu J, Zhan CG, Liao F. Facile Alkaline Lysis of Escherichia coli Cells in High-Throughput Mode for Screening Enzyme Mutants: Arylsulfatase as an Example. Appl Biochem Biotechnol 2016; 179:545-57. [DOI: 10.1007/s12010-016-2012-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 02/08/2016] [Indexed: 12/14/2022]
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Bai S, Wallis JG, Denolf P, Browse J. Directed evolution increases desaturation of a cyanobacterial fatty acid desaturase in eukaryotic expression systems. Biotechnol Bioeng 2016; 113:1522-30. [PMID: 26724425 DOI: 10.1002/bit.25922] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 12/17/2015] [Accepted: 12/29/2015] [Indexed: 12/21/2022]
Affiliation(s)
- Shuangyi Bai
- Institute of Biological Chemistry; Washington State University; Pullman Washington
| | - James G. Wallis
- Institute of Biological Chemistry; Washington State University; Pullman Washington
| | - Peter Denolf
- Bayer CropScience N.V.; Technologiepark 38; Ghent Belgium
| | - John Browse
- Institute of Biological Chemistry; Washington State University; Pullman Washington
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Classification, mode of action and production strategy of xylanase and its application for biofuel production from water hyacinth. Int J Biol Macromol 2016; 82:1041-54. [DOI: 10.1016/j.ijbiomac.2015.10.086] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/26/2015] [Accepted: 10/27/2015] [Indexed: 01/07/2023]
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25
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Fungal Biotechnology for Industrial Enzyme Production: Focus on (Hemi)cellulase Production Strategies, Advances and Challenges. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27951-0_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ruller R, Alponti J, Deliberto LA, Zanphorlin LM, Machado CB, Ward RJ. Concommitant adaptation of a GH11 xylanase by directed evolution to create an alkali-tolerant/thermophilic enzyme. Protein Eng Des Sel 2015; 27:255-62. [PMID: 25096197 DOI: 10.1093/protein/gzu027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
As part of an ongoing directed evolution program, the catalytic performance of the Xylanase A from Bacillus subtilis (XynA), which presents temperature and pH optima of 50°C and 6.0, respectively, has been enhanced to create a highly thermostable and alkali-tolerant enzyme. A library of random XynA mutants generated by error-prone polymerase chain reaction was screened by halo formation on agar containing xylan at pH 8.0. Two mutants showing higher catalytic activity at elevated pH in relation to the wild-type XynA were selected, and pooled with a further 5 XynA variants selected by screening thermostable XynA obtained from a previous directed evolution study for activity at alkaline pH. This pool of variants was used as a template for a further round of error-prone polymerase chain reaction and DNase fragment shuffling, with screening at pH 12.0 at 55°C. Selected mutants were subjected to further DNase shuffling, and a final round of screening at pH 12.0 and 80°C. A XynA variant containing eight mutations was isolated (Q7H/G13R/S22P/S31Y/T44A/I51V/I107L/S179C) that presented a temperature optimum of 80°C, a 3-fold increase in the specific activity compared with the wild-type enzyme at pH 8.0, and a 50% loss of activity (t50) of 60 min at 80°C (wild type <2 min). This directed evolution strategy therefore allows the concomitant adaption of increased thermostability and alkali tolerance of an endo-xylanase.
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Affiliation(s)
- Roberto Ruller
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE) - CNPEM, Campinas, SP, Brazil Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, CEP 14040-901, Ribeirão Preto, SP, Brazil
| | - Juliana Alponti
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, CEP 14040-901, Ribeirão Preto, SP, Brazil
| | - Laila Aparecida Deliberto
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, CEP 14040-901, Ribeirão Preto, SP, Brazil
| | | | - Carla Botelho Machado
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE) - CNPEM, Campinas, SP, Brazil Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, CEP 14040-901, Ribeirão Preto, SP, Brazil
| | - Richard John Ward
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE) - CNPEM, Campinas, SP, Brazil Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, CEP 14040-901, Ribeirão Preto, SP, Brazil
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Currin A, Swainston N, Day PJ, Kell DB. Synthetic biology for the directed evolution of protein biocatalysts: navigating sequence space intelligently. Chem Soc Rev 2015; 44:1172-239. [PMID: 25503938 PMCID: PMC4349129 DOI: 10.1039/c4cs00351a] [Citation(s) in RCA: 251] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 12/21/2022]
Abstract
The amino acid sequence of a protein affects both its structure and its function. Thus, the ability to modify the sequence, and hence the structure and activity, of individual proteins in a systematic way, opens up many opportunities, both scientifically and (as we focus on here) for exploitation in biocatalysis. Modern methods of synthetic biology, whereby increasingly large sequences of DNA can be synthesised de novo, allow an unprecedented ability to engineer proteins with novel functions. However, the number of possible proteins is far too large to test individually, so we need means for navigating the 'search space' of possible protein sequences efficiently and reliably in order to find desirable activities and other properties. Enzymologists distinguish binding (Kd) and catalytic (kcat) steps. In a similar way, judicious strategies have blended design (for binding, specificity and active site modelling) with the more empirical methods of classical directed evolution (DE) for improving kcat (where natural evolution rarely seeks the highest values), especially with regard to residues distant from the active site and where the functional linkages underpinning enzyme dynamics are both unknown and hard to predict. Epistasis (where the 'best' amino acid at one site depends on that or those at others) is a notable feature of directed evolution. The aim of this review is to highlight some of the approaches that are being developed to allow us to use directed evolution to improve enzyme properties, often dramatically. We note that directed evolution differs in a number of ways from natural evolution, including in particular the available mechanisms and the likely selection pressures. Thus, we stress the opportunities afforded by techniques that enable one to map sequence to (structure and) activity in silico, as an effective means of modelling and exploring protein landscapes. Because known landscapes may be assessed and reasoned about as a whole, simultaneously, this offers opportunities for protein improvement not readily available to natural evolution on rapid timescales. Intelligent landscape navigation, informed by sequence-activity relationships and coupled to the emerging methods of synthetic biology, offers scope for the development of novel biocatalysts that are both highly active and robust.
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Affiliation(s)
- Andrew Currin
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
| | - Neil Swainston
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- School of Computer Science , The University of Manchester , Manchester M13 9PL , UK
| | - Philip J. Day
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- Faculty of Medical and Human Sciences , The University of Manchester , Manchester M13 9PT , UK
| | - Douglas B. Kell
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
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High-level production of creatine amidinohydrolase from Arthrobacter nicotianae 23710 in Escherichia coli. Appl Biochem Biotechnol 2014; 175:2564-73. [PMID: 25536878 DOI: 10.1007/s12010-014-1460-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 12/16/2014] [Indexed: 10/24/2022]
Abstract
In the present study, the gene encoding creatinase was amplified from Arthrobacter nicotianae 23710 (CICC) and functionally overexpressed in Escherichia coli. By applying a two-stage temperature control strategy, the production of creatinase was increased up to 61.3 U/mL in 3-L fermentor with a high productivity of 6.1 U/mL/h. The recombinant creatinase shows excellent resistance to the chelating agent EDTA, the surfactants (Tween 20, Tween 80, and Triton X-100) and the common preservative NaN3 (20 mM). High-level expression of the recombinant creatinase will contribute to its application in clinical diagnosis of renal function.
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An enzymatic platform for the synthesis of isoprenoid precursors. PLoS One 2014; 9:e105594. [PMID: 25153179 PMCID: PMC4143292 DOI: 10.1371/journal.pone.0105594] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/23/2014] [Indexed: 12/13/2022] Open
Abstract
The isoprenoid family of compounds is estimated to contain ∼65,000 unique structures including medicines, fragrances, and biofuels. Due to their structural complexity, many isoprenoids can only be obtained by extraction from natural sources, an inherently risky and costly process. Consequently, the biotechnology industry is attempting to genetically engineer microorganisms that can produce isoprenoid-based drugs and fuels on a commercial scale. Isoprenoid backbones are constructed from two, five-carbon building blocks, isopentenyl 5-pyrophosphate and dimethylallyl 5-pyrophosphate, which are end-products of either the mevalonate or non-mevalonate pathways. By linking the HMG-CoA reductase pathway (which produces mevalonate) to the mevalonate pathway, these building block can be synthesized enzymatically from acetate, ATP, NAD(P)H and CoA. Here, the enzymes in these pathways are used to produce pathway intermediates and end-products in single-pot reactions and in remarkably high yield, ∼85%. A strategy for the regio-specific incorporation of isotopes into isoprenoid backbones is developed and used to synthesize a series of isotopomers of diphosphomevalonate, the immediate end-product of the mevalonate pathway. The enzymatic system is shown to be robust and capable of producing quantities of product in aqueous solutions that meet or exceed the highest levels achieved using genetically engineered organisms in high-density fermentation.
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Yao J, Guo GS, Ren GH, Liu YH. Production, characterization and applications of tannase. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcatb.2013.11.018] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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31
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Accelerated protein engineering for chemical biotechnology via homologous recombination. Curr Opin Biotechnol 2013; 24:1017-22. [DOI: 10.1016/j.copbio.2013.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 02/28/2013] [Accepted: 03/05/2013] [Indexed: 12/22/2022]
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Taniguchi N, Nakayama S, Kawakami T, Murakami H. Patch cloning method for multiple site-directed and saturation mutagenesis. BMC Biotechnol 2013; 13:91. [PMID: 24164925 PMCID: PMC3829206 DOI: 10.1186/1472-6750-13-91] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/23/2013] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Various DNA manipulation methods have been developed to prepare mutant genes for protein engineering. However, development of more efficient and convenient method is still demanded. Homologous DNA assembly methods, which do not depend on restriction enzymes, have been used as convenient tools for cloning and have been applied to site-directed mutagenesis recently. This study describes an optimized homologous DNA assembly method, termed as multiple patch cloning (MUPAC), for multiple site-directed and saturation mutagenesis. RESULTS To demonstrate MUPAC, we introduced five back mutations to a mutant green fluorescent protein (GFPuv) with five deleterious mutations at specific sites and transformed Escherichia coli (E. coli) with the plasmids obtained. We observed that the over 90% of resulting colonies possessed the plasmids containing the reverted GFPuv gene and exhibited fluorescence. We extended the test to introduce up to nine mutations in Moloney Murine Leukemia Virus reverse transcriptase (M-MLV RT) by assembling 11 DNA fragments using MUPAC. Analysis of the cloned plasmid by electrophoresis and DNA sequencing revealed that approximately 30% of colonies had the objective mutant M-MLV RT gene. Furthermore, we also utilized this method to prepare a library of mutant GFPuv genes containing saturation mutations at five specific sites, and we found that MUPAC successfully introduced NNK codons at all five sites, whereas other site remained intact. CONCLUSIONS MUPAC could efficiently introduce various mutations at multiple specific sites within a gene. Furthermore, it could facilitate the preparation of experimental gene materials important to molecular and synthetic biology research.
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Affiliation(s)
| | | | | | - Hiroshi Murakami
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
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Expression and function of a modified AP2/ERF transcription factor from Brassica napus enhances cold tolerance in transgenic Arabidopsis. Mol Biotechnol 2013; 53:198-206. [PMID: 22351429 DOI: 10.1007/s12033-012-9515-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
One of the most rapid and effective defensive mechanisms plants have for protecting themselves, from a variety of biotic and abiotic stresses, is the regulation of plant signal transcription factors. AP2/ERF factors play an important role in plant development as well as in hormonal regulation and cold response. Directed evolution is a powerful tool to modify proteins, improving their properties, and for studying their structure-function relations. Here, the transgenic Arabidopsis plants over-expressed a mutant gene, BnaERF-B3-hy15-mu3, which encoded for a factor that exhibited more binding activity with the GCC box element than the wild-type gene BnaERF-B3-hy15 encode factor, and exhibited more freezing tolerance than transgenic plants containing the original BnaERF-B3-hy15 gene. Real-time PCR analyses also revealed that the expression levels of several stress-regulated genes were altered in the over-expressed BnaERF-B3-hy15-mu3 transgenic lines. The BnaERF-B3-hy15 responded to exogenous ABA. Using RT-PCR analysis, the expression of BnaERF-B3-hy15 at different stages and stress treatments were also analyzed.
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Using evolutionary computations to understand the design and evolution of gene and cell regulatory networks. Methods 2013; 62:39-55. [PMID: 23726941 DOI: 10.1016/j.ymeth.2013.05.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 11/30/2012] [Accepted: 05/21/2013] [Indexed: 12/21/2022] Open
Abstract
This paper surveys modeling approaches for studying the evolution of gene regulatory networks (GRNs). Modeling of the design or 'wiring' of GRNs has become increasingly common in developmental and medical biology, as a means of quantifying gene-gene interactions, the response to perturbations, and the overall dynamic motifs of networks. Drawing from developments in GRN 'design' modeling, a number of groups are now using simulations to study how GRNs evolve, both for comparative genomics and to uncover general principles of evolutionary processes. Such work can generally be termed evolution in silico. Complementary to these biologically-focused approaches, a now well-established field of computer science is Evolutionary Computations (ECs), in which highly efficient optimization techniques are inspired from evolutionary principles. In surveying biological simulation approaches, we discuss the considerations that must be taken with respect to: (a) the precision and completeness of the data (e.g. are the simulations for very close matches to anatomical data, or are they for more general exploration of evolutionary principles); (b) the level of detail to model (we proceed from 'coarse-grained' evolution of simple gene-gene interactions to 'fine-grained' evolution at the DNA sequence level); (c) to what degree is it important to include the genome's cellular context; and (d) the efficiency of computation. With respect to the latter, we argue that developments in computer science EC offer the means to perform more complete simulation searches, and will lead to more comprehensive biological predictions.
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Van Dien S. From the first drop to the first truckload: commercialization of microbial processes for renewable chemicals. Curr Opin Biotechnol 2013; 24:1061-8. [PMID: 23537815 DOI: 10.1016/j.copbio.2013.03.002] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 02/27/2013] [Accepted: 03/05/2013] [Indexed: 01/24/2023]
Abstract
Fermentation of carbohydrate substrates by microorganisms represents an attractive route for the manufacture of industrial chemicals from renewable resources. The technology to manipulate metabolism of bacteria and yeast, including the introduction of heterologous chemical pathways, has accelerated research in this field. However, the public literature contains very few examples of strains achieving the production metrics required for commercialization. This article presents the challenges in reaching commercial titer, yield, and productivity targets, along with other necessary strain and process characteristics. It then reviews various methods in systems biology, synthetic biology, enzyme engineering, and fermentation engineering which can be applied to strain improvement, and presents a strategy for using these tools to overcome the major hurdles on the path to commercialization.
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Affiliation(s)
- Stephen Van Dien
- Genomatica, Inc., 10520 Wateridge Circle, San Diego, CA 92121, United States.
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36
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Sharma A, Satyanarayana T. Microbial acid-stable α-amylases: Characteristics, genetic engineering and applications. Process Biochem 2013. [DOI: 10.1016/j.procbio.2012.12.018] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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37
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Arunachalam TS, Wichert C, Appel B, Müller S. Mixed oligonucleotides for random mutagenesis: best way of making them. Org Biomol Chem 2012; 10:4641-50. [PMID: 22552713 DOI: 10.1039/c2ob25328c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The generation of proteins, especially enzymes, with pre-deliberated, novel properties is a big challenge in the field of protein engineering. This aim, over the years was critically facilitated by newly emerging methods of combinatorial and evolutionary techniques, such as combinatorial gene synthesis followed by functional screening of many structural variants generated in parallel (library). Libraries can be generated by a large number of available methods. Therein the use of mixtures of pre-formed trinucleotide blocks representing codons for the 20 canonical amino acids for oligonucleotide synthesis stands out as allowing fully controlled partial (or total) randomization individually at any number of arbitrarily chosen codon positions of a given gene. This has created substantial demand of fully protected trinucleotide synthons of good reactivity in standard oligonucleotide synthesis. We here review methods for the preparation of oligonucleotide mixtures with a strong focus on codon-specific trinucleotide blocks.
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Affiliation(s)
- Tamil Selvi Arunachalam
- Institut für Biochemie, Ernst Moritz Arndt Universität, Felix Hausdorff Strasse 4, Greifswald, D-17487, Germany
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Janczyk M, Appel B, Springstubbe D, Fritz HJ, Müller S. A new and convenient approach for the preparation of β-cyanoethyl protected trinucleotide phosphoramidites. Org Biomol Chem 2012; 10:1510-3. [PMID: 22231393 DOI: 10.1039/c2ob06934b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein we report a convenient approach for the preparation of fully protected trinucleotide synthons to be used for the synthesis of gene libraries. The trinucleotide synthons bear β-cyanoethyl groups at the phosphate residues, and thus can be used in standard oligonucleotide synthesis without additional steps for deprotection and work-up.
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Affiliation(s)
- Matthäus Janczyk
- Ernst-Moritz-Arndt-Universität Greifswald, Institut für Biochemie, Felix-Hausdorff-Str., 4, 17487 Greifswald, Germany
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39
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Restriction enzyme-free construction of random gene mutagenesis libraries in Escherichia coli. Anal Biochem 2011; 421:640-8. [PMID: 22155067 DOI: 10.1016/j.ab.2011.11.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 11/07/2011] [Accepted: 11/10/2011] [Indexed: 11/22/2022]
Abstract
Directed evolution relies on both random and site-directed mutagenesis of individual genes and regulatory elements to create variants with altered activity profiles for engineering applications. Central to these experiments is the construction of large libraries of related variants. However, a number of technical hurdles continue to limit routine construction of random mutagenesis libraries in Escherichia coli, in particular, inefficiencies during digestion and ligation steps. Here, we report a restriction enzyme-free approach to library generation using megaprimers termed MegAnneal. Target DNA is first exponentially amplified using error-prone polymerase chain reaction (PCR) and then linearly amplified with a single 3' primer to generate long, randomly mutated, single-stranded megaprimers. These are annealed to single-stranded dUTP-containing template plasmid and extended with T7 polymerase to create a complementary strand, and the resulting termini are ligated with T4 DNA ligase. Using this approach, we are able to reliably generate libraries of approximately 10⁷ colony-forming units (cfu)/μg DNA/transformation in a single day. We have created MegAnneal libraries based on three different single-chain antibodies and identified variants with enhanced expression and ligand-binding affinity. The key advantages of this approach include facile amplification, restriction enzyme-free library generation, and a significantly reduced risk of mutations outside the targeted region and wild-type contamination as compared with current methods.
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40
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Acidophilic bacteria and archaea: acid stable biocatalysts and their potential applications. Extremophiles 2011; 16:1-19. [PMID: 22080280 DOI: 10.1007/s00792-011-0402-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 10/05/2011] [Indexed: 01/05/2023]
Abstract
Acidophiles are ecologically and economically important group of microorganisms, which thrive in acidic natural (solfataric fields, sulfuric pools) as well as artificial man-made (areas associated with human activities such as mining of coal and metal ores) environments. They possess networked cellular adaptations to regulate pH inside the cell. Several extracellular enzymes from acidophiles are known to be functional at much lower pH than the cytoplasmic pH. Enzymes like amylases, proteases, ligases, cellulases, xylanases, α-glucosidases, endoglucanases, and esterases stable at low pH are known from various acidophilic microbes. The possibility of improving them by genetic engineering and directed evolution will further boost their industrial applications. Besides biocatalysts, other biomolecules such as plasmids, rusticynin, and maltose-binding protein have also been reported from acidophiles. Some strategies for circumventing the problems encountered in expressing genes encoding proteins from extreme acidophiles have been suggested. The investigations on the analysis of crystal structures of some acidophilic proteins have thrown light on their acid stability. Attempts are being made to use thermoacidophilic microbes for biofuel production from lignocellulosic biomass. The enzymes from acidophiles are mainly used in polymer degradation.
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41
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Sharma PK, Kumar R, Kumar R, Mohammad O, Singh R, Kaur J. Engineering of a metagenome derived lipase toward thermal tolerance: effect of asparagine to lysine mutation on the protein surface. Gene 2011; 491:264-71. [PMID: 22001407 DOI: 10.1016/j.gene.2011.09.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 09/15/2011] [Accepted: 09/24/2011] [Indexed: 11/16/2022]
Abstract
A highly thermostable mutant lipase was generated and characterized. Mutant enzyme demonstrated 144 fold enhanced thermostability over the wild type enzyme at 60°C. Interestingly, the overall catalytic efficiency (k(cat/)K(m)) of mutant was also enhanced (~20 folds). Circular dichroism spectroscopy, studied as function of temperature, demonstrated that the mutant lipase retained its secondary structure up to 70-80°C, whereas wild type protein structure was completely distorted above 35°C. Additionally, the intrinsic tryptophan fluorescence (a probe for the tertiary structure) also displayed difference in the conformation of two enzymes during temperature dependent unfolding. Furthermore, mutation N355K resulted in extensive H-bonding (Lys355 HZ1OE2 Glu284) with a distance 2.44 Å. In contrast to this, Wt enzyme has not shown such H-bonding interaction.
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42
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43
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Hokanson CA, Cappuccilli G, Odineca T, Bozic M, Behnke CA, Mendez M, Coleman WJ, Crea R. Engineering highly thermostable xylanase variants using an enhanced combinatorial library method. Protein Eng Des Sel 2011; 24:597-605. [DOI: 10.1093/protein/gzr028] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Zhang W, Wang M, Huang Y, Chea S, Zheng Z, Qian X, Shen Y. New and highly efficient methodology for screening high-yield strains of cytotoxic deacetylmycoepoxydiene (DAM). Lett Appl Microbiol 2011; 52:441-7. [DOI: 10.1111/j.1472-765x.2011.03015.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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45
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Kim YC. Introducing predetermined mutations throughout a target gene using TDEM (transposon-directed base-exchange mutagenesis). Methods Mol Biol 2011; 705:275-293. [PMID: 21125393 DOI: 10.1007/978-1-61737-967-3_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Transposon-directed base-exchange mutagenesis (TDEM) is an efficient and controllable method for introducing a mutation(s) into a gene. Each round of TDEM removes a predetermined number of bases (up to 11 base pairs) from a randomly selected site within the target gene and replaces them with any length of DNA of predetermined sequence. Therefore, the number of bases to be deleted and inserted can be precisely regulated. Because each round of TDEM generates mutation(s) at a single site, the number of mutations introduced can be determined by the number of cycles of TDEM. Furthermore, using a novel frame-checking procedure, non-functional mutants containing a frameshift or stop codon can be minimized. Thus, TDEM can be used to introduce a limited and predetermined change at each round of mutagenesis, thereby providing a useful tool for studying protein structure and function.
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Affiliation(s)
- Yun Cheol Kim
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, Los Angeles, CA, USA.
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46
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Fernandes P. Enzymes in food processing: a condensed overview on strategies for better biocatalysts. Enzyme Res 2010; 2010:862537. [PMID: 21048872 PMCID: PMC2963163 DOI: 10.4061/2010/862537] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Accepted: 09/01/2010] [Indexed: 11/20/2022] Open
Abstract
Food and feed is possibly the area where processing anchored in biological agents has the deepest roots. Despite this, process improvement or design and implementation of novel approaches has been consistently performed, and more so in recent years, where significant advances in enzyme engineering and biocatalyst design have fastened the pace of such developments. This paper aims to provide an updated and succinct overview on the applications of enzymes in the food sector, and of progresses made, namely, within the scope of tapping for more efficient biocatalysts, through screening, structural modification, and immobilization of enzymes. Targeted improvements aim at enzymes with enhanced thermal and operational stability, improved specific activity, modification of pH-activity profiles, and increased product specificity, among others. This has been mostly achieved through protein engineering and enzyme immobilization, along with improvements in screening. The latter has been considerably improved due to the implementation of high-throughput techniques, and due to developments in protein expression and microbial cell culture. Expanding screening to relatively unexplored environments (marine, temperature extreme environments) has also contributed to the identification and development of more efficient biocatalysts. Technological aspects are considered, but economic aspects are also briefly addressed.
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Affiliation(s)
- Pedro Fernandes
- Institute for Biotechnology and Bioengineering (IBB), Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Avenue Rovisco Pais, 1049-001 Lisboa, Portugal
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Kumar A, Grover S, Sharma J, Batish VK. Chymosin and other milk coagulants: sources and biotechnological interventions. Crit Rev Biotechnol 2010; 30:243-58. [DOI: 10.3109/07388551.2010.483459] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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48
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Determining the safety of enzymes used in animal feed. Regul Toxicol Pharmacol 2010; 56:332-42. [DOI: 10.1016/j.yrtph.2009.10.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 10/21/2009] [Accepted: 10/22/2009] [Indexed: 11/23/2022]
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Transposon-directed base-exchange mutagenesis (TDEM): a novel method for multiple-nucleotide substitutions within a target gene. Biotechniques 2009; 46:534-42. [PMID: 19594453 DOI: 10.2144/000113152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In this report we describe transposon-directed base-exchange mutagenesis (TDEM), an efficient and controllable method for introducing a mutation into a gene. Each round of TDEM can remove up to 11 base pairs from a randomly selected site within the target gene and replace them with any length of DNA of predetermined sequence. Therefore, the number of bases to be deleted and inserted can be independently regulated providing greater versatility than existing methods of transposon-based mutagenesis. Subsequently, multiple rounds of mutagenesis will provide a diverse mutant library that contains multiple mutations throughout the gene. Additionally, we developed a simple frame-checking procedure that eliminates nonfunctional mutants containing frameshifts or stop codons. As a proof of principle, we used TDEM to generate mutant lacZalpha lacking alpha-complementation activity and recovered active revertants using a second round of TDEM. Furthermore, a single round of TDEM yielded unique, inactive mutants of ccdB.
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50
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Abstract
Anthropogenic compounds used as pesticides, solvents and explosives often persist in the environment and can cause toxicity to humans and wildlife. The persistence of anthropogenic compounds is due to their recent introduction into the environment; microbes in soil and water have had relatively little time to evolve efficient mechanisms for degradation of these new compounds. Some anthropogenic compounds are easily degraded, whereas others are degraded very slowly or only partially, leading to accumulation of toxic products. This review examines the factors that affect the ability of microbes to degrade anthropogenic compounds and the mechanisms by which new pathways emerge in nature. New approaches for engineering microbes with enhanced degradative abilities include assembly of pathways using enzymes from multiple organisms, directed evolution of inefficient enzymes, and genome shuffling to improve microbial fitness under the challenging conditions posed by contaminated environments.
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