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Kirchner L, Müller V, Averhoff B. A temperature dependent pilin promoter for production of thermostable enzymes in Thermus thermophilus. Microb Cell Fact 2023; 22:187. [PMID: 37726752 PMCID: PMC10507856 DOI: 10.1186/s12934-023-02192-1] [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: 07/27/2023] [Accepted: 09/02/2023] [Indexed: 09/21/2023] Open
Abstract
BACKGROUND Enzymes from thermophiles are of great interest for research and bioengineering due to their stability and efficiency. Thermophilic expression hosts such as Thermus thermophilus [T. thermophilus] can overcome specific challenges experienced with protein production in mesophilic expression hosts, such as leading to better folding, increased protein stability, solubility, and enzymatic activity. However, available inducible promoters for efficient protein production in T. thermophilus HB27 are limited. RESULTS In this study, we characterized the pilA4 promoter region and evaluated its potential as a tool for production of thermostable enzymes in T. thermophilus HB27. Reporter gene analysis using a promoterless β-glucosidase gene revealed that the pilA4 promoter is highly active under optimal growth conditions at 68 °C and downregulated during growth at 80 °C. Furthermore, growth in minimal medium led to significantly increased promoter activity in comparison to growth in complex medium. Finally, we proved the suitability of the pilA4 promoter for heterologous production of thermostable enzymes in T. thermophilus by producing a fully active soluble mannitol-1-phosphate dehydrogenase from Thermoanaerobacter kivui [T. kivui], which is used in degradation of brown algae that are rich in mannitol. CONCLUSIONS Our results show that the pilA4 promoter is an efficient tool for gene expression in T. thermophilus with a high potential for use in biotechnology and synthetic biology applications.
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Affiliation(s)
- Lennart Kirchner
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue- Str. 9, 60438, Frankfurt, Germany
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue- Str. 9, 60438, Frankfurt, Germany
| | - Beate Averhoff
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue- Str. 9, 60438, Frankfurt, Germany.
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Amarelle V, Roldán DM, Fabiano E, Guazzaroni ME. Synthetic Biology Toolbox for Antarctic Pseudomonas sp. Strains: Toward a Psychrophilic Nonmodel Chassis for Function-Driven Metagenomics. ACS Synth Biol 2023; 12:722-734. [PMID: 36862944 DOI: 10.1021/acssynbio.2c00543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
One major limitation of function-driven metagenomics is the ability of the host to express the metagenomic DNA correctly. Differences in the transcriptional, translational, and post-translational machinery between the organism to which the DNA belongs and the host strain are all factors that influence the success of a functional screening. For this reason, the use of alternative hosts is an appropriate approach to favor the identification of enzymatic activities in function-driven metagenomics. To be implemented, appropriate tools should be designed to build the metagenomic libraries in those hosts. Moreover, discovery of new chassis and characterization of synthetic biology toolbox in nonmodel bacteria is an active field of research to expand the potential of these organisms in processes of industrial interest. Here, we assessed the suitability of two Antarctic psychrotolerant Pseudomonas strains as putative alternative hosts for function-driven metagenomics using pSEVA modular vectors as scaffold. We determined a set of synthetic biology tools suitable for these hosts and, as a proof of concept, we demonstrated their fitness for heterologous protein expression. These hosts represent a step forward for the prospection and identification of psychrophilic enzymes of biotechnological interest.
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Affiliation(s)
- Vanesa Amarelle
- Departamento de Bioquímica y Genómica Microbianas. Instituto de Investigaciones Biológicas Clemente Estable, Av. Italia 3318, Montevideo 11600, Uruguay
| | - Diego M Roldán
- Departamento de Bioquímica y Genómica Microbianas. Instituto de Investigaciones Biológicas Clemente Estable, Av. Italia 3318, Montevideo 11600, Uruguay
| | - Elena Fabiano
- Departamento de Bioquímica y Genómica Microbianas. Instituto de Investigaciones Biológicas Clemente Estable, Av. Italia 3318, Montevideo 11600, Uruguay
| | - María-Eugenia Guazzaroni
- Departamento de Biologia. FFCLRP, University of São Paulo, 14049-901 Ribeirão Preto, São Paulo, Brazil
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Rebets Y, Kormanec J, Lutzhetskyy A, Bernaerts K, Anné J. Cloning and Expression of Metagenomic DNA in Streptomyces lividans and Its Subsequent Fermentation for Optimized Production. Methods Mol Biol 2023; 2555:213-260. [PMID: 36306090 DOI: 10.1007/978-1-0716-2795-2_16] [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] [Indexed: 06/16/2023]
Abstract
The choice of an expression system for the metagenomic DNA of interest is of vital importance for the detection of any particular gene or gene cluster. Most of the screens to date have used the Gram-negative bacterium Escherichia coli as a host for metagenomic gene libraries. However, the use of E. coli introduces a potential host bias since only 40% of the enzymatic activities may be readily recovered by random cloning in E. coli. To recover some of the remaining 60%, alternative cloning hosts such as Streptomyces spp. have been used. Streptomycetes are high-GC Gram-positive bacteria belonging to the Actinomycetales and they have been studied extensively for more than 25 years as an alternative expression system. They are extremely well suited for the expression of DNA from other actinomycetes and genomes of high GC content. Furthermore, due to its high innate, extracellular secretion capacity, Streptomyces can be a better system than E. coli for the production of many extracellular proteins. In this article, an overview is given about the materials and methods for growth and successful expression and secretion of heterologous proteins from diverse origin using Streptomyces lividans as a host. More in detail, an overview is given about the protocols of transformation, type of plasmids used and of vectors useful for integration of DNA into the host chromosome, and accompanying cloning strategies. In addition, various control elements for gene expression including synthetic promoters are discussed, and methods to compare their strength are described. Stable and efficient marker-less integration of the gene of interest under the control of the promoter of choice into S. lividans chromosome via homologous recombination using pAMR23A-based system will be explained. Finally, a basic protocol for bench-top bioreactor experiments which can form the start in the production process optimization and up-scaling will be provided.
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Affiliation(s)
| | - Jan Kormanec
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Andriy Lutzhetskyy
- Department of Pharmaceutical Biotechnology, University of Saarland, Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), University of Saarland, Saarbrücken, Germany
| | - Kristel Bernaerts
- Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety Division, KU Leuven, Leuven, Belgium
| | - Jozef Anné
- Department of Microbiology, Immunology and Transplantation, lab. Molecular Bacteriology, Rega Institute, KU Leuven, Leuven, Belgium.
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Pabbathi NPP, Velidandi A, Tavarna T, Gupta S, Raj RS, Gandam PK, Baadhe RR. Role of metagenomics in prospecting novel endoglucanases, accentuating functional metagenomics approach in second-generation biofuel production: a review. BIOMASS CONVERSION AND BIOREFINERY 2023; 13:1371-1398. [PMID: 33437563 PMCID: PMC7790359 DOI: 10.1007/s13399-020-01186-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/30/2020] [Accepted: 12/01/2020] [Indexed: 05/02/2023]
Abstract
As the fossil fuel reserves are depleting rapidly, there is a need for alternate fuels to meet the day to day mounting energy demands. As fossil fuel started depleting, a quest for alternate forms of fuel was initiated and biofuel is one of its promising outcomes. First-generation biofuels are made from edible sources like vegetable oils, starch, and sugars. Second-generation biofuels (SGB) are derived from lignocellulosic crops and the third-generation involves algae for biofuel production. Technical challenges in the production of SGB are hampering its commercialization. Advanced molecular technologies like metagenomics can help in the discovery of novel lignocellulosic biomass-degrading enzymes for commercialization and industrial production of SGB. This review discusses the metagenomic outcomes to enlighten the importance of unexplored habitats for novel cellulolytic gene mining. It also emphasizes the potential of different metagenomic approaches to explore the uncultivable cellulose-degrading microbiome as well as cellulolytic enzymes associated with them. This review also includes effective pre-treatment technology and consolidated bioprocessing for efficient biofuel production.
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Affiliation(s)
- Ninian Prem Prashanth Pabbathi
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Aditya Velidandi
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Tanvi Tavarna
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Shreyash Gupta
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Ram Sarvesh Raj
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Pradeep Kumar Gandam
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
| | - Rama Raju Baadhe
- Integrated Biorefinery Research Lab, Department of Biotechnology, National Institute of Technology, Warangal, Telangana 506004 India
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Liu Y, Angelov A, Feiler W, Baudrexl M, Zverlov V, Liebl W, Vanderhaeghen S. Arabinan saccharification by biogas reactor metagenome-derived arabinosyl hydrolases. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:121. [PMID: 36371193 PMCID: PMC9655821 DOI: 10.1186/s13068-022-02216-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Plant cell walls represent the most plentiful renewable organic resource on earth, but due to their heterogeneity, complex structure and partial recalcitrance, their use as biotechnological feedstock is still limited. RESULTS In order to identify efficient enzymes for polysaccharide breakdown, we have carried out functional screening of metagenomic fosmid libraries from biogas fermenter microbial communities grown on sugar beet pulp, an arabinan-rich agricultural residue, or other sources containing microbes that efficiently depolymerize polysaccharides, using CPH (chromogenic polysaccharide hydrogel) or ICB (insoluble chromogenic biomass) labeled polysaccharide substrates. Seventy-one depolymerase-encoding genes were identified from 55 active fosmid clones by using Illumina and Sanger sequencing and dbCAN CAZyme (carbohydrate-active enzyme) annotation. An around 56 kb assembled DNA fragment putatively originating from Xylanivirga thermophila strain or a close relative was analyzed in detail. It contained 48 ORFs (open reading frames), of which 31 were assigned to sugar metabolism. Interestingly, a large number of genes for enzymes putatively involved in degradation and utilization of arabinose-containing carbohydrates were found. Seven putative arabinosyl hydrolases from this DNA fragment belonging to glycoside hydrolase (GH) families GH51 and GH43 were biochemically characterized, revealing two with endo-arabinanase activity and four with exo-α-L-arabinofuranosidase activity but with complementary cleavage properties. These enzymes were found to act synergistically and can completely hydrolyze SBA (sugar beet arabinan) and DA (debranched arabinan). CONCLUSIONS We screened 32,776 fosmid clones from several metagenomic libraries with chromogenic lignocellulosic substrates for functional enzymes to advance the understanding about the saccharification of recalcitrant lignocellulose. Seven putative X. thermophila arabinosyl hydrolases were characterized for pectic substrate degradation. The arabinosyl hydrolases displayed maximum activity and significant long-term stability around 50 °C. The enzyme cocktails composed in this study fully degraded the arabinan substrates and thus could serve for arabinose production in food and biofuel industries.
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Affiliation(s)
- Yajing Liu
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
- Present Address: Chair of Chemistry of Biogenic Resources, Technical University of Munich, Schulgasse 16, 94315 Straubing, Germany
| | - Angel Angelov
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
- Present Address: NGS Competence Center Tübingen, Universitätsklinikum Tübingen, Calwerstraße 7, 72076 Tübingen, Germany
| | - Werner Feiler
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
| | - Melanie Baudrexl
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
| | - Vladimir Zverlov
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
| | - Wolfgang Liebl
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
| | - Sonja Vanderhaeghen
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Straβe 4, 85354 Freising-Weihenstephan, Germany
- Present Address: IMGM Laboratories, Lochhamer Straße 29a, 82152 Planegg, Germany
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Chen G, Bai R, Zhang Y, Zhao B, Xiao Y. Application of metagenomics to biological wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:150737. [PMID: 34606860 DOI: 10.1016/j.scitotenv.2021.150737] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 09/20/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
Biological wastewater treatment is a process in which the microbial metabolism of complex communities transforms pollutants into low- or non-toxic products. Due to the absence of an in-depth understanding of the diversity and complexity of microbial communities, it is very likely to ignore the potential mechanisms of microbial community in wastewater treatment. Metagenomics is a technology based on molecular biology, in which massive gene sequences are obtained from environmental samples and analyzed by bioinformatics to determine the composition and function of a microbial community. Metagenomics can identify the state of microbes in their native environments more effectively than traditional molecular methods. This review summarizes the application of metagenomics to assess microbial communities in biological wastewater treatment, such as the biological removal of phosphorus and nitrogen by bacteria, the study of antibiotic resistance genes (ARGs), and the reduction of heavy metals by microbial communities, with an emphasis on the contribution of microbial diversity and metabolic diversity. Technical bottlenecks in the application of metagenomics to biological wastewater treatment are elucidated, and future research directions for metagenomics are proposed, among which the application of multi-omics will be an important research method for future biological wastewater treatment.
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Affiliation(s)
- Geng Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Rui Bai
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yiqing Zhang
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Biyi Zhao
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yong Xiao
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Robinson SL, Piel J, Sunagawa S. A roadmap for metagenomic enzyme discovery. Nat Prod Rep 2021; 38:1994-2023. [PMID: 34821235 PMCID: PMC8597712 DOI: 10.1039/d1np00006c] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Indexed: 12/13/2022]
Abstract
Covering: up to 2021Metagenomics has yielded massive amounts of sequencing data offering a glimpse into the biosynthetic potential of the uncultivated microbial majority. While genome-resolved information about microbial communities from nearly every environment on earth is now available, the ability to accurately predict biocatalytic functions directly from sequencing data remains challenging. Compared to primary metabolic pathways, enzymes involved in secondary metabolism often catalyze specialized reactions with diverse substrates, making these pathways rich resources for the discovery of new enzymology. To date, functional insights gained from studies on environmental DNA (eDNA) have largely relied on PCR- or activity-based screening of eDNA fragments cloned in fosmid or cosmid libraries. As an alternative, shotgun metagenomics holds underexplored potential for the discovery of new enzymes directly from eDNA by avoiding common biases introduced through PCR- or activity-guided functional metagenomics workflows. However, inferring new enzyme functions directly from eDNA is similar to searching for a 'needle in a haystack' without direct links between genotype and phenotype. The goal of this review is to provide a roadmap to navigate shotgun metagenomic sequencing data and identify new candidate biosynthetic enzymes. We cover both computational and experimental strategies to mine metagenomes and explore protein sequence space with a spotlight on natural product biosynthesis. Specifically, we compare in silico methods for enzyme discovery including phylogenetics, sequence similarity networks, genomic context, 3D structure-based approaches, and machine learning techniques. We also discuss various experimental strategies to test computational predictions including heterologous expression and screening. Finally, we provide an outlook for future directions in the field with an emphasis on meta-omics, single-cell genomics, cell-free expression systems, and sequence-independent methods.
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Affiliation(s)
| | - Jörn Piel
- Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland.
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A multi-omic screening approach for the discovery of thermoactive glycoside hydrolases. Extremophiles 2021; 25:101-114. [PMID: 33416984 DOI: 10.1007/s00792-020-01214-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/21/2020] [Indexed: 01/02/2023]
Abstract
Next-generation sequencing and computational biology have facilitated the implementation of new combinatorial screening approaches to discover novel enzymes of biotechnological interest. In this study, we describe the successful establishment of a multi-omic approach for the identification of thermostable hydrolase-encoding genes by determination of gene expression levels. We applied this combinatorial approach using an anaerobic enrichment culture from an Azorean hot spring sample grown on green coffee beans as recalcitrant substrate. An in-depth analysis of the microbial community resulted in microorganisms capable of metabolizing the selected substrate, such as the genera Caloramator, Dictyoglomus and Thermoanaerobacter as active and abundant microorganisms. To discover glycoside hydrolases, 90,342 annotated genes were screened for specific reaction types. A total number of 106 genes encoding cellulases (EC 3.2.1.4), beta-glucosidases (EC 3.2.1.21) and endo-1,4-beta-mannosidases (EC 3.2.1.78) were selected. Mapping of RNA-Seq reads to the related metagenome led to expression levels for each gene. Amongst those, 14 genes, encoding glycoside hydrolases, showed highest expression values, and were used for further cloning. Four proteins were biochemically characterized and were identified as thermoactive glycoside hydrolases with a broad substrate range. This work demonstrated that a combinatory omic approach is a suitable strategy identifying unique thermoactive enzymes from environmental samples.
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Loeschcke A, Thies S. Engineering of natural product biosynthesis in Pseudomonas putida. Curr Opin Biotechnol 2020; 65:213-224. [PMID: 32498036 DOI: 10.1016/j.copbio.2020.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/01/2020] [Accepted: 03/30/2020] [Indexed: 01/03/2023]
Affiliation(s)
- Anita Loeschcke
- Institute of Molecular Enzyme Technology, Heinrich-Heine-University Düsseldorf, Germany.
| | - Stephan Thies
- Institute of Molecular Enzyme Technology, Heinrich-Heine-University Düsseldorf, Germany.
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Wiltschi B, Cernava T, Dennig A, Galindo Casas M, Geier M, Gruber S, Haberbauer M, Heidinger P, Herrero Acero E, Kratzer R, Luley-Goedl C, Müller CA, Pitzer J, Ribitsch D, Sauer M, Schmölzer K, Schnitzhofer W, Sensen CW, Soh J, Steiner K, Winkler CK, Winkler M, Wriessnegger T. Enzymes revolutionize the bioproduction of value-added compounds: From enzyme discovery to special applications. Biotechnol Adv 2020; 40:107520. [DOI: 10.1016/j.biotechadv.2020.107520] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 10/18/2019] [Accepted: 01/13/2020] [Indexed: 12/11/2022]
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Markel U, Essani KD, Besirlioglu V, Schiffels J, Streit WR, Schwaneberg U. Advances in ultrahigh-throughput screening for directed enzyme evolution. Chem Soc Rev 2020; 49:233-262. [PMID: 31815263 DOI: 10.1039/c8cs00981c] [Citation(s) in RCA: 142] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Enzymes are versatile catalysts and their synthetic potential has been recognized for a long time. In order to exploit their full potential, enzymes often need to be re-engineered or optimized for a given application. (Semi-) rational design has emerged as a powerful means to engineer proteins, but requires detailed knowledge about structure function relationships. In turn, directed evolution methodologies, which consist of iterative rounds of diversity generation and screening, can improve an enzyme's properties with virtually no structural knowledge. Current diversity generation methods grant us access to a vast sequence space (libraries of >1012 enzyme variants) that may hide yet unexplored catalytic activities and selectivity. However, the time investment for conventional agar plate or microtiter plate-based screening assays represents a major bottleneck in directed evolution and limits the improvements that are obtainable in reasonable time. Ultrahigh-throughput screening (uHTS) methods dramatically increase the number of screening events per time, which is crucial to speed up biocatalyst design, and to widen our knowledge about sequence function relationships. In this review, we summarize recent advances in uHTS for directed enzyme evolution. We shed light on the importance of compartmentalization to preserve the essential link between genotype and phenotype and discuss how cells and biomimetic compartments can be applied to serve this function. Finally, we discuss how uHTS can inspire novel functional metagenomics approaches to identify natural biocatalysts for novel chemical transformations.
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Affiliation(s)
- Ulrich Markel
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany.
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12
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Nora LC, Westmann CA, Guazzaroni ME, Siddaiah C, Gupta VK, Silva-Rocha R. Recent advances in plasmid-based tools for establishing novel microbial chassis. Biotechnol Adv 2019; 37:107433. [PMID: 31437573 DOI: 10.1016/j.biotechadv.2019.107433] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 07/11/2019] [Accepted: 08/16/2019] [Indexed: 12/28/2022]
Abstract
A key challenge for domesticating alternative cultivable microorganisms with biotechnological potential lies in the development of innovative technologies. Within this framework, a myriad of genetic tools has flourished, allowing the design and manipulation of complex synthetic circuits and genomes to become the general rule in many laboratories rather than the exception. More recently, with the development of novel technologies such as DNA automated synthesis/sequencing and powerful computational tools, molecular biology has entered the synthetic biology era. In the beginning, most of these technologies were established in traditional microbial models (known as chassis in the synthetic biology framework) such as Escherichia coli and Saccharomyces cerevisiae, enabling fast advances in the field and the validation of fundamental proofs of concept. However, it soon became clear that these organisms, although extremely useful for prototyping many genetic tools, were not ideal for a wide range of biotechnological tasks due to intrinsic limitations in their molecular/physiological properties. Over the last decade, researchers have been facing the great challenge of shifting from these model systems to non-conventional chassis with endogenous capacities for dealing with specific tasks. The key to address these issues includes the generation of narrow and broad host plasmid-based molecular tools and the development of novel methods for engineering genomes through homologous recombination systems, CRISPR/Cas9 and other alternative methods. Here, we address the most recent advances in plasmid-based tools for the construction of novel cell factories, including a guide for helping with "build-your-own" microbial host.
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Affiliation(s)
- Luísa Czamanski Nora
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Cauã Antunes Westmann
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - María-Eugenia Guazzaroni
- Faculty of Philosophy, Science and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | | | - Vijai Kumar Gupta
- ERA Chair of Green Chemistry, Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, 12618 Tallinn, Estonia
| | - Rafael Silva-Rocha
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil.
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13
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Gupta V, Singh I, Kumar P, Rasool S, Verma V. A hydrolase with esterase activity expressed from a fosmid gene bank prepared from DNA of a North West Himalayan glacier frozen soil sample. 3 Biotech 2019; 9:107. [PMID: 30863691 DOI: 10.1007/s13205-019-1621-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 02/08/2019] [Indexed: 01/26/2023] Open
Abstract
Screening of 20,000 clones of a fosmid gene bank, constructed from DNA extracted from North West Himalaya (NWH) glacier soil sample, using functional approach identified 10 esterase/lipase-producing clones. Of these, a clone designated pFG43 with an insert size of 45 kb which produced the highest concentration of enzyme (467.43 U/mg) was sequenced. Clone pFG43 contained 61 open reading frames (ORF) and of these an ORF of 1155 bp designated ME-003, was found to be closely related to a hydrolase from Acidobacteria sps (77% sequence identity and E value = 1e-164) and subsequently identified as a putative cocaine esterase. ORF ME-003 was amplified and sub-cloned using a TA vector system into E. coli (DH5α). The purified recombinant enzyme with a molecular weight of 43 kDa had optimal activity at 40 °C, pH 6 and the highest activity with shorter chain fatty acids than with higher chain length fatty acids. There is insignificant effect of inhibitors on the enzyme activity of ME-003, except PMSF which completely inhibited its activity. ME-003 activity was also inhibited in the presence of copper oxide but remained stable in presence of other metal ions. The enzyme activity was also inhibited in the presence of organic solvents; however, in the presence of 10% isopropanol, 12% of enzymatic activity was retained. Among various detergents, SDS completely inhibited enzymatic activity. The recombinant enzyme also shows enantio-specific activity against the racemic drug intermediates/precursors and exhibited 90% ee against racemic 1-phenyl ethanol and fluoxetine.
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Affiliation(s)
- Verruchi Gupta
- 1School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India
| | - Inderpal Singh
- 1School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India.,2Bioinformatics Infrastructure Facility (BIF), School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India
| | - Paramdeep Kumar
- 3Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab 143005 India
| | - Shafaq Rasool
- 1School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India
| | - Vijeshwar Verma
- 1School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India.,2Bioinformatics Infrastructure Facility (BIF), School of Biotechnology, Shri Mata Vaishno Devi University, Kakryal, Katra, Jammu and Kashmir 182320 India
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14
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Castilla IA, Woods DF, Reen FJ, O'Gara F. Harnessing Marine Biocatalytic Reservoirs for Green Chemistry Applications through Metagenomic Technologies. Mar Drugs 2018; 16:E227. [PMID: 29973493 PMCID: PMC6071119 DOI: 10.3390/md16070227] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/13/2018] [Accepted: 06/22/2018] [Indexed: 01/24/2023] Open
Abstract
In a demanding commercial world, large-scale chemical processes have been widely utilised to satisfy consumer related needs. Chemical industries are key to promoting economic growth and meeting the requirements of a sustainable industrialised society. The market need for diverse commodities produced by the chemical industry is rapidly expanding globally. Accompanying this demand is an increased threat to the environment and to human health, due to waste produced by increased industrial production. This increased demand has underscored the necessity to increase reaction efficiencies, in order to reduce costs and increase profits. The discovery of novel biocatalysts is a key method aimed at combating these difficulties. Metagenomic technology, as a tool for uncovering novel biocatalysts, has great potential and applicability and has already delivered many successful achievements. In this review we discuss, recent developments and achievements in the field of biocatalysis. We highlight how green chemistry principles through the application of biocatalysis, can be successfully promoted and implemented in various industrial sectors. In addition, we demonstrate how two novel lipases/esterases were mined from the marine environment by metagenomic analysis. Collectively these improvements can result in increased efficiency, decreased energy consumption, reduced waste and cost savings for the chemical industry.
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Affiliation(s)
- Ignacio Abreu Castilla
- BIOMERIT Research Centre, School of Microbiology, University College Cork, T12 K8AF Cork, Ireland.
| | - David F Woods
- BIOMERIT Research Centre, School of Microbiology, University College Cork, T12 K8AF Cork, Ireland.
| | - F Jerry Reen
- School of Microbiology, University College Cork, T12 K8AF Cork, Ireland.
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork, T12 K8AF Cork, Ireland.
- Telethon Kids Institute, Perth, WA 6008, Australia.
- Human Microbiome Programme, School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA 6102, Australia.
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15
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Westmann CA, Alves LDF, Silva-Rocha R, Guazzaroni ME. Mining Novel Constitutive Promoter Elements in Soil Metagenomic Libraries in Escherichia coli. Front Microbiol 2018; 9:1344. [PMID: 29973927 PMCID: PMC6019500 DOI: 10.3389/fmicb.2018.01344] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 05/31/2018] [Indexed: 11/13/2022] Open
Abstract
Although functional metagenomics has been widely employed for the discovery of genes relevant to biotechnology and biomedicine, its potential for assessing the diversity of transcriptional regulatory elements of microbial communities has remained poorly explored. Here, we experimentally mined novel constitutive promoter sequences in metagenomic libraries by combining a bi-directional reporter vector, high-throughput fluorescence assays and predictive computational methods. Through the expression profiling of fluorescent clones from two independent soil sample libraries, we have analyzed the regulatory dynamics of 260 clones with candidate promoters as a set of active metagenomic promoters in the host Escherichia coli. Through an in-depth analysis of selected clones, we were able to further explore the architecture of metagenomic fragments and to report the presence of multiple promoters per fragment with a dominant promoter driving the expression profile. These approaches resulted in the identification of 33 novel active promoters from metagenomic DNA originated from very diverse phylogenetic groups. The in silico and in vivo analysis of these individual promoters allowed the generation of a constitutive promoter consensus for exogenous sequences recognizable by E. coli in metagenomic studies. The results presented here demonstrates the potential of functional metagenomics for exploring environmental bacterial communities as a source of novel regulatory genetic parts to expand the toolbox for microbial engineering.
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Affiliation(s)
- Cauã A Westmann
- Department of Cellular and Molecular Biology, FMRP, University of São Paulo, Ribeirão Preto, Brazil
| | - Luana de Fátima Alves
- Department of Biology, FFCLRP, University of São Paulo, Ribeirão Preto, Brazil.,Department of Biochemistry, FMRP, University of São Paulo, Ribeirão Preto, Brazil
| | - Rafael Silva-Rocha
- Department of Cellular and Molecular Biology, FMRP, University of São Paulo, Ribeirão Preto, Brazil
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16
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Fulton A, Hayes MR, Schwaneberg U, Pietruszka J, Jaeger KE. High-Throughput Screening Assays for Lipolytic Enzymes. Methods Mol Biol 2018; 1685:209-231. [PMID: 29086311 DOI: 10.1007/978-1-4939-7366-8_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Screening is defined as the identification of hits within a large library of variants of an enzyme or protein with a predefined property. In theory, each variant present in the respective library needs to be assayed; however, to save time and consumables, many screening regimes involve a primary round to identify clones producing active enzymes. Such primary or prescreenings for lipolytic enzyme activity are often carried out on agar plates containing pH indicators or substrates as triolein or tributyrin. Subsequently, high-throughput screening assays are usually performed in microtiter plate (MTP) format using chromogenic or fluorogenic substrates and, if available, automated liquid handling robotics. Here, we describe different assay systems to determine the activity and enantioselectivity of lipases and esterases as well as the synthesis of several substrates. We also report on the construction of a complete site saturation library derived from lipase A of Bacillus subtilis and its testing for detergent tolerance. This approach allows for the identification of amino acids affecting sensitivity or resistance against different detergents.
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Affiliation(s)
- Alexander Fulton
- Institute of Molecular Enzyme Technology, Heinrich-Heine - Universität Düsseldorf, Forschungszentrum Jülich, 52426, Jülich, Germany
- Novozymes A/S, Krogshoejvej 36, 2880, Bagsvaerd, Denmark
| | - Marc R Hayes
- Institute of Bioorganic Chemistry, Heinrich-Heine - Universität Düsseldorf, Forschungszentrum Jülich, 52426, Jülich, Germany
| | - Ulrich Schwaneberg
- Lehrstuhl für Biotechnologie, RWTH Aachen University, 52074, Aachen, Germany
- DWI Leibniz-Institute for Interactive Materials at RWTH Aachen University, 52056, Aachen, Germany
| | - Jörg Pietruszka
- Institute of Bioorganic Chemistry, Heinrich-Heine - Universität Düsseldorf, Forschungszentrum Jülich, 52426, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52428, Jülich, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich-Heine - Universität Düsseldorf, Forschungszentrum Jülich, 52426, Jülich, Germany.
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52428, Jülich, Germany.
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17
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Angelov A, Pham VTT, Übelacker M, Brady S, Leis B, Pill N, Brolle J, Mechelke M, Moerch M, Henrissat B, Liebl W. A metagenome-derived thermostable β-glucanase with an unusual module architecture which defines the new glycoside hydrolase family GH148. Sci Rep 2017; 7:17306. [PMID: 29229913 PMCID: PMC5725463 DOI: 10.1038/s41598-017-16839-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/16/2017] [Indexed: 12/15/2022] Open
Abstract
The discovery of novel and robust enzymes for the breakdown of plant biomass bears tremendous potential for the development of sustainable production processes in the rapidly evolving new bioeconomy. By functional screening of a metagenomic library from a volcano soil sample a novel thermostable endo-β-glucanase (EngU) which is unusual with regard to its module architecture and cleavage specificity was identified. Various recombinant EngU variants were characterized. Assignment of EngU to an existing glycoside hydrolase (GH) family was not possible. Two regions of EngU showed weak sequence similarity to proteins of the GH clan GH-A, and acidic residues crucial for catalytic activity of EngU were identified by mutation. Unusual, a carbohydrate-binding module (CBM4) which displayed binding affinity for β-glucan, lichenin and carboxymethyl-cellulose was found as an insertion between these two regions. EngU hydrolyzed β-1,4 linkages in carboxymethyl-cellulose, but displayed its highest activity with mixed linkage (β-1,3-/β-1,4-) glucans such as barley β-glucan and lichenin, where in contrast to characterized lichenases cleavage occurred predominantly at the β-1,3 linkages of C4-substituted glucose residues. EngU and numerous related enzymes with previously unknown function represent a new GH family of biomass-degrading enzymes within the GH-A clan. The name assigned to the new GH family is GH148.
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Affiliation(s)
- Angel Angelov
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Vu Thuy Trang Pham
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Maria Übelacker
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Silja Brady
- Department of Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Georg-August University Göttingen, Göttingen, Germany
| | - Benedikt Leis
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Nicole Pill
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Judith Brolle
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Matthias Mechelke
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Matthias Moerch
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Bernard Henrissat
- Architecture et Function des Macromolécules Biologiques, CNRS, Aix-Marseille University, Marseille, France
| | - Wolfgang Liebl
- Department of Microbiology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising-Weihenstephan, Germany.
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18
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Berini F, Casciello C, Marcone GL, Marinelli F. Metagenomics: novel enzymes from non-culturable microbes. FEMS Microbiol Lett 2017; 364:4329276. [DOI: 10.1093/femsle/fnx211] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/02/2017] [Indexed: 01/02/2023] Open
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19
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Kinfu BM, Jahnke M, Janus M, Besirlioglu V, Roggenbuck M, Meurer R, Vojcic L, Borchert M, Schwaneberg U, Chow J, Streit WR. Recombinant RNA Polymerase from Geobacillus
sp. GHH01 as tool for rapid generation of metagenomic RNAs using in vitro technologies. Biotechnol Bioeng 2017; 114:2739-2752. [DOI: 10.1002/bit.26436] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/09/2017] [Accepted: 08/21/2017] [Indexed: 01/18/2023]
Affiliation(s)
- Birhanu M. Kinfu
- Microbiology and Biotechnology, Biocenter Klein Flottbek; University of Hamburg; Ohnhorststr Hamburg Germany
| | - Maike Jahnke
- Microbiology and Biotechnology, Biocenter Klein Flottbek; University of Hamburg; Ohnhorststr Hamburg Germany
| | - Mareike Janus
- Microbiology and Biotechnology, Biocenter Klein Flottbek; University of Hamburg; Ohnhorststr Hamburg Germany
| | | | | | | | | | | | | | - Jennifer Chow
- Microbiology and Biotechnology, Biocenter Klein Flottbek; University of Hamburg; Ohnhorststr Hamburg Germany
| | - Wolfgang R. Streit
- Microbiology and Biotechnology, Biocenter Klein Flottbek; University of Hamburg; Ohnhorststr Hamburg Germany
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20
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Advanced microbial analysis for wastewater quality monitoring: metagenomics trend. Appl Microbiol Biotechnol 2017; 101:7445-7458. [DOI: 10.1007/s00253-017-8490-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 08/19/2017] [Indexed: 12/20/2022]
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21
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Duarte M, Nielsen A, Camarinha-Silva A, Vilchez-Vargas R, Bruls T, Wos-Oxley ML, Jauregui R, Pieper DH. Functional soil metagenomics: elucidation of polycyclic aromatic hydrocarbon degradation potential following 12 years of in situ bioremediation. Environ Microbiol 2017; 19:2992-3011. [PMID: 28401633 DOI: 10.1111/1462-2920.13756] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 03/29/2017] [Accepted: 04/06/2017] [Indexed: 11/27/2022]
Abstract
A culture-independent function-based screening approach was used to assess the microbial aerobic catabolome for polycyclic aromatic hydrocarbons degradation of a soil subjected to 12 years of in situ bioremediation. A total of 422 750 fosmid clones were screened for key aromatic ring-cleavage activities using 2,3-dihydroxybiphenyl as substrate. Most of the genes encoding ring-cleavage enzymes on the 768 retrieved positive fosmids could not be identified using primer-based approaches and, thus, 205 fosmid inserts were sequenced. Nearly two hundred extradiol dioxygenase encoding genes of three different superfamilies could be identified. Additional key genes of aromatic metabolic pathways were identified, including a high abundance of Rieske non-heme iron oxygenases that provided detailed information on enzymes activating aromatic compounds and enzymes involved in activation of the side chain of methylsubstituted aromatics. The gained insights indicated a complex microbial network acting at the site under study, which comprises organisms similar to recently identified Immundisolibacter cernigliae TR3.2 and Rugosibacter aromaticivorans Ca6 and underlined the great potential of an approach that combines an activity-screening, a cost-effective high-throughput sequencing of fosmid clones and a phylogenomic-routed and manually curated database to carefully identify key proteins dedicated to aerobic degradation of aromatic compounds.
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Affiliation(s)
- Márcia Duarte
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany
| | - Agnes Nielsen
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany
| | - Amélia Camarinha-Silva
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany
| | - Ramiro Vilchez-Vargas
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany.,Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke-University, Magdeburg, Germany
| | - Thomas Bruls
- Institut de Génomique, Genoscope, UMR8030 (CNRS, CEA, Université d'Evry), Evry, France
| | - Melissa L Wos-Oxley
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany
| | - Ruy Jauregui
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany.,AgResearch Grasslands, Tennent drive, Palmerston North, New Zealand
| | - Dietmar H Pieper
- Microbial Interactions and Processes Research Group, HZI - Helmholtz Centre for Infection Research, Inhoffenstr. 7, Braunschweig, D-38124, Germany
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22
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Crofts TS, Gasparrini AJ, Dantas G. Next-generation approaches to understand and combat the antibiotic resistome. Nat Rev Microbiol 2017; 15:422-434. [PMID: 28392565 DOI: 10.1038/nrmicro.2017.28] [Citation(s) in RCA: 309] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Antibiotic resistance is a natural feature of diverse microbial ecosystems. Although recent studies of the antibiotic resistome have highlighted barriers to the horizontal transfer of antibiotic resistance genes between habitats, the rapid global spread of genes that confer resistance to carbapenem, colistin and quinolone antibiotics illustrates the dire clinical and societal consequences of such events. Over time, the study of antibiotic resistance has grown from focusing on single pathogenic organisms in axenic culture to studying antibiotic resistance in pathogenic, commensal and environmental bacteria at the level of microbial communities. As the study of antibiotic resistance advances, it is important to incorporate this comprehensive approach to better inform global antibiotic resistance surveillance and antibiotic development. It is increasingly becoming apparent that although not all resistance genes are likely to geographically and phylogenetically disseminate, the threat presented by those that are is serious and warrants an interdisciplinary research focus. In this Review, we highlight seminal work in the resistome field, discuss recent advances in the studies of resistomes, and propose a resistome paradigm that can pave the way for the improved proactive identification and mitigation of emerging antibiotic resistance threats.
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Affiliation(s)
- Terence S Crofts
- Center for Genome Sciences &Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Campus Box 8510, St. Louis, Missouri 63110, USA
| | - Andrew J Gasparrini
- Center for Genome Sciences &Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Campus Box 8510, St. Louis, Missouri 63110, USA
| | - Gautam Dantas
- Center for Genome Sciences &Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Campus Box 8510, St. Louis, Missouri 63110, USA.,Department of Pathology and Immunology, Washington University School of Medicine.,Department of Molecular Microbiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, USA.,Department of Biomedical Engineering, Washington University in St. Louis, 1 Brookings Drive, St. Louis, Missouri 63130, USA
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23
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Mair P, Gielen F, Hollfelder F. Exploring sequence space in search of functional enzymes using microfluidic droplets. Curr Opin Chem Biol 2017; 37:137-144. [PMID: 28390246 DOI: 10.1016/j.cbpa.2017.02.018] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 02/08/2017] [Accepted: 02/15/2017] [Indexed: 12/21/2022]
Abstract
Screening of enzyme mutants in monodisperse picoliter compartments, generated at kilohertz speed in microfluidic devices, is coming of age. After a decade of proof-of-principle experiments, workflows have emerged that combine existing microfluidic modules to assay reaction progress quantitatively and yield improved enzymes. Recent examples of the screening of libraries of randomised proteins and from metagenomic sources suggest that this approach is not only faster and cheaper, but solves problems beyond the feasibility scope of current methodologies. The establishment of new assays in this format - so far covering hydrolases, aldolases, polymerases and dehydrogenases - will enable the exploration of sequence space for new catalysts of natural and non-natural chemical transformations.
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Affiliation(s)
- Philip Mair
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Fabrice Gielen
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK; Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Florian Hollfelder
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
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24
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Smart M, Huddy RJ, Cowan DA, Trindade M. Liquid Phase Multiplex High-Throughput Screening of Metagenomic Libraries Using p-Nitrophenyl-Linked Substrates for Accessory Lignocellulosic Enzymes. Methods Mol Biol 2017; 1539:219-228. [PMID: 27900692 DOI: 10.1007/978-1-4939-6691-2_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
To access the genetic potential contained in large metagenomic libraries, suitable high-throughput functional screening methods are required. Here we describe a high-throughput screening approach which enables the rapid identification of metagenomic library clones expressing functional accessory lignocellulosic enzymes. The high-throughput nature of this method hinges on the multiplexing of both the E. coli metagenomic library clones and the colorimetric p-nitrophenyl linked substrates which allows for the simultaneous screening for β-glucosidases, β-xylosidases, and α-L-arabinofuranosidases. This method is readily automated and compatible with high-throughput robotic screening systems.
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Affiliation(s)
- Mariette Smart
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
- Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, South Africa
| | - Robert J Huddy
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
- Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, South Africa
| | - Don A Cowan
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
- Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, South Africa
| | - Marla Trindade
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa.
- Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, South Africa.
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25
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Rebets Y, Kormanec J, Luzhetskyy A, Bernaerts K, Anné J. Cloning and Expression of Metagenomic DNA in Streptomyces lividans and Subsequent Fermentation for Optimized Production. Methods Mol Biol 2017; 1539:99-144. [PMID: 27900687 DOI: 10.1007/978-1-4939-6691-2_8] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The choice of an expression system for the metagenomic DNA of interest is of vital importance for the detection of any particular gene or gene cluster. Most of the screens to date have used the gram-negative bacterium Escherichia coli as a host for metagenomic gene libraries. However, the use of E. coli introduces a potential host bias since only 40 % of the enzymatic activities may be readily recovered by random cloning in E. coli. To recover some of the remaining 60 %, alternative cloning hosts such as Streptomyces spp. have been used. Streptomycetes are high-GC gram-positive bacteria belonging to the Actinomycetales and they have been studied extensively for more than 15 years as an alternative expression system. They are extremely well suited for the expression of DNA from other actinomycetes and genomes of high GC content. Furthermore, due to its high innate, extracellular secretion capacity, Streptomyces can be a better system than E. coli for the production of many extracellular proteins. In this article an overview is given about the materials and methods for growth and successful expression and secretion of heterologous proteins from diverse origin using Streptomyces lividans has a host. More in detail, an overview is given about the protocols of transformation, type of plasmids used and of vectors useful for integration of DNA into the host chromosome, and accompanying cloning strategies. In addition, various control elements for gene expression including synthetic promoters are discussed, and methods to compare their strength are described. Integration of the gene of interest under the control of the promoter of choice into S. lividans chromosome via homologous recombination using pAMR4-based system is explained. Finally a basic protocol for benchtop bioreactor experiments which can form the start in the production process optimization and upscaling is provided.
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Affiliation(s)
- Yuriy Rebets
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), University of Saarland, Saarbrücken, Germany
| | - Jan Kormanec
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Andriy Luzhetskyy
- Actinobacteria Metabolic Engineering Group, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), University of Saarland, Saarbrücken, Germany
- Department of Pharmaceutical Biotechnology, University of Saarland, Saarbrücken, Germany
| | - Kristel Bernaerts
- Department of Chemical Engineering, KU Leuven (University of Leuven), Leuven, Belgium
| | - Jozef Anné
- Lab. Molecular Bacteriology, Department Microbiology and Immunology, Rega Institute, KU Leuven (University of Leuven), Box 1037, Herestraat 49, B-3000, Leuven, Belgium.
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26
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Katzke N, Knapp A, Loeschcke A, Drepper T, Jaeger KE. Novel Tools for the Functional Expression of Metagenomic DNA. Methods Mol Biol 2017; 1539:159-196. [PMID: 27900689 DOI: 10.1007/978-1-4939-6691-2_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Functional expression of genes from metagenomic libraries is limited by various factors including inefficient transcription and/or translation of target genes as well as improper folding and assembly of the corresponding proteins caused by the lack of appropriate chaperones and cofactors. It is now well accepted that the use of different expression hosts of distinct phylogeny and physiology can dramatically increase the rate of success. In the following chapter, we therefore describe tools and protocols allowing for the comparative heterologous expression of genes in five bacterial expression hosts, namely Escherichia coli, Pseudomonas putida, Bacillus subtilis, Burkholderia glumae, and Rhodobacter capsulatus. Different broad-host-range shuttle vectors are described that allow activity-based screening of metagenomic DNA in these bacteria. Furthermore, we describe the newly developed transfer-and-expression system TREX which comprises genetic elements essential to allow for expression of large clusters of functionally coupled genes in different microbial species.
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Affiliation(s)
- Nadine Katzke
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich GmbH, Heinrich-Heine-University Düsseldorf, 52426, Jülich, Germany
| | - Andreas Knapp
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich GmbH, Heinrich-Heine-University Düsseldorf, 52426, Jülich, Germany
| | - Anita Loeschcke
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich GmbH, Heinrich-Heine-University Düsseldorf, 52426, Jülich, Germany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich GmbH, Heinrich-Heine-University Düsseldorf, 52426, Jülich, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich GmbH, Heinrich-Heine-University Düsseldorf, 52426, Jülich, Germany.
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27
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Weiland-Bräuer N, Langfeldt D, Schmitz RA. Construction and Screening of Marine Metagenomic Large Insert Libraries. Methods Mol Biol 2017; 1539:23-42. [PMID: 27900682 DOI: 10.1007/978-1-4939-6691-2_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The marine environment covers more than 70 % of the world's surface. Marine microbial communities are highly diverse and have evolved during extended evolutionary processes of physiological adaptations under the influence of a variety of ecological conditions and selection pressures. They harbor an enormous diversity of microbes with still unknown and probably new physiological characteristics. In the past, marine microbes, mostly bacteria of microbial consortia attached to marine tissues of multicellular organisms, have proven to be a rich source of highly potent bioactive compounds, which represent a considerable number of drug candidates. However, to date, the biodiversity of marine microbes and the versatility of their bioactive compounds and metabolites have not been fully explored. This chapter describes sampling in the marine environment, construction of metagenomic large insert libraries from marine habitats, and exemplarily one function based screen of metagenomic clones for identification of quorum quenching activities.
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Affiliation(s)
- Nancy Weiland-Bräuer
- Institut für Allgemeine Mikrobiologie, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, 24118, Kiel, Germany
| | - Daniela Langfeldt
- Institut für Allgemeine Mikrobiologie, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, 24118, Kiel, Germany
| | - Ruth A Schmitz
- Institut für Allgemeine Mikrobiologie, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, 24118, Kiel, Germany.
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Abstract
There are a range of methodologies available to study the human microbiota, ranging from traditional approaches such as culturing through to state-of-the-art developments in next generation DNA sequencing technologies. The advent of molecular techniques in particular has opened up tremendous new avenues for research, and has galvanised interest in the study of our microbial inhabitants. Given the dazzling array of available options, however, it is important to understand the inherent advantages and limitations of each technique so that the best approach can be employed to address the particular research objective. In this chapter we cover some of the most widely used current techniques in human microbiota research and highlight the particular strengths and caveats associated with each approach.
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Affiliation(s)
- Alan W Walker
- Microbiology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
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Metagenomic discovery of novel enzymes and biosurfactants in a slaughterhouse biofilm microbial community. Sci Rep 2016; 6:27035. [PMID: 27271534 PMCID: PMC4897644 DOI: 10.1038/srep27035] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/04/2016] [Indexed: 12/02/2022] Open
Abstract
DNA derived from environmental samples is a rich source of novel bioactive molecules. The choice of the habitat to be sampled predefines the properties of the biomolecules to be discovered due to the physiological adaptation of the microbial community to the prevailing environmental conditions. We have constructed a metagenomic library in Escherichia coli DH10b with environmental DNA (eDNA) isolated from the microbial community of a slaughterhouse drain biofilm consisting mainly of species from the family Flavobacteriaceae. By functional screening of this library we have identified several lipases, proteases and two clones (SA343 and SA354) with biosurfactant and hemolytic activities. Sequence analysis of the respective eDNA fragments and subsequent structure homology modelling identified genes encoding putative N-acyl amino acid synthases with a unique two-domain organisation. The produced biosurfactants were identified by NMR spectroscopy as N-acyltyrosines with N-myristoyltyrosine as the predominant species. Critical micelle concentration and reduction of surface tension were similar to those of chemically synthesised N-myristoyltyrosine. Furthermore, we showed that the newly isolated N-acyltyrosines exhibit antibiotic activity against various bacteria. This is the first report describing the successful application of functional high-throughput screening assays for the identification of biosurfactant producing clones within a metagenomic library.
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Martin M, Vandermies M, Joyeux C, Martin R, Barbeyron T, Michel G, Vandenbol M. Discovering novel enzymes by functional screening of plurigenomic libraries from alga-associated Flavobacteriia and Gammaproteobacteria. Microbiol Res 2016; 186-187:52-61. [PMID: 27242143 DOI: 10.1016/j.micres.2016.03.005] [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: 02/04/2016] [Revised: 03/17/2016] [Accepted: 03/22/2016] [Indexed: 11/22/2022]
Abstract
Alga-associated microorganisms, in the context of their numerous interactions with the host and the complexity of the marine environment, are known to produce diverse hydrolytic enzymes with original biochemistry. We recently isolated several macroalgal-polysaccharide-degrading bacteria from the surface of the brown alga Ascophyllum nodosum. These active isolates belong to two classes: the Flavobacteriia and the Gammaproteobacteria. In the present study, we constructed two "plurigenomic" (with multiple bacterial genomes) libraries with the 5 most interesting isolates (regarding their phylogeny and their enzymatic activities) of each class (Fv and Gm libraries). Both libraries were screened for diverse hydrolytic activities. Five activities, out of the 48 previously identified in the natural polysaccharolytic isolates, were recovered by functional screening: a xylanase (GmXyl7), a beta-glucosidase (GmBg1), an esterase (GmEst7) and two iota-carrageenases (Fvi2.5 and Gmi1.3). We discuss here the potential role of the used host-cell, the average DNA insert-sizes and the used restriction enzymes on the divergent screening yields obtained for both libraries and get deeper inside the "great screen anomaly". Interestingly, the discovered esterase probably stands for a novel family of homoserine o-acetyltransferase-like-esterases, while the two iota-carrageenases represent new members of the poorly known GH82 family (containing only 19 proteins since its description in 2000). These original results demonstrate the efficiency of our uncommon "plurigenomic" library approach and the underexplored potential of alga-associated cultivable microbiota for the identification of novel and algal-specific enzymes.
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Affiliation(s)
- Marjolaine Martin
- Microbiology and Genomics Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium.
| | - Marie Vandermies
- Microbial Processes and Interactions, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium
| | - Coline Joyeux
- Microbiology and Genomics Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium
| | - Renée Martin
- Microbiology and Genomics Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium
| | - Tristan Barbeyron
- Sorbonne Université, UPMC Univ Paris 06, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, Bretagne, France
| | - Gurvan Michel
- Sorbonne Université, UPMC Univ Paris 06, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, Bretagne, France
| | - Micheline Vandenbol
- Microbiology and Genomics Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium
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Barshakh I, Elleuche S. Is it possible to optimize the protein production yield by the generation of homomultimeric fusion enzymes? SPRINGERPLUS 2016; 5:316. [PMID: 27066347 PMCID: PMC4788654 DOI: 10.1186/s40064-016-1968-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 03/03/2016] [Indexed: 01/08/2023]
Abstract
Background The supply of industrially relevant biocatalysts demands an easy and efficient protein production in high yield. In a conventional approach, a recombinant protein is produced in a heterologous host enabling the manipulation of multiple parameters including expression plasmids, growth conditions and regulation of protein biosynthesis. In this study, the generation of homomultimeric fusion genes is tested as an additional parameter to increase the production yield of a heat-stable cellulase. Findings The LE (LguI/Eco81I)-cloning strategy was used to generate a set of plasmids containing a single copy or two to four repetitions of the endoglucanase-encoding gene cel5A from the thermophilic anaerobe Fervidobacterium gondwanense. Serial up-scaling of shaking flask volumes from 50 to 500 mL were used to determine the production yield of active cellulolytic enzyme Cel5A in recombinant form in Escherichia coli. Monitoring the cellular wet weight and total protein proved that the bacterial growth rate is not depending on the production of fusion enzymes, however activity assays in combination with Western blotting analyses indicated instability effects of large homomultimeric fusion enzymes. Conclusion The production yield of fusion cellulases is constant with increasing molecular weights, but improved activities were not observed for recombinant Cel5A homomultimers. This strategy may serve as a starting point for further studies to generate more stable fusion proteins with improved catalytic activities and higher protein yield in the future. Electronic supplementary material The online version of this article (doi:10.1186/s40064-016-1968-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Iryna Barshakh
- Institute for Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, 21073 Hamburg, Germany
| | - Skander Elleuche
- Institute for Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, 21073 Hamburg, Germany
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32
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Mirete S, Morgante V, González-Pastor JE. Functional metagenomics of extreme environments. Curr Opin Biotechnol 2016; 38:143-9. [PMID: 26901403 DOI: 10.1016/j.copbio.2016.01.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/28/2016] [Accepted: 01/29/2016] [Indexed: 10/22/2022]
Abstract
The bioprospecting of enzymes that operate under extreme conditions is of particular interest for many biotechnological and industrial processes. Nevertheless, there is a considerable limitation to retrieve novel enzymes as only a small fraction of microorganisms derived from extreme environments can be cultured under standard laboratory conditions. Functional metagenomics has the advantage of not requiring the cultivation of microorganisms or previous sequence information to known genes, thus representing a valuable approach for mining enzymes with new features. In this review, we summarize studies showing how functional metagenomics was employed to retrieve genes encoding for proteins involved not only in molecular adaptation and resistance to extreme environmental conditions but also in other enzymatic activities of biotechnological interest.
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Affiliation(s)
- Salvador Mirete
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, Madrid, Spain
| | - Verónica Morgante
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, Madrid, Spain
| | - José Eduardo González-Pastor
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, Madrid, Spain.
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33
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Fernández FJ, Vega MC. Choose a Suitable Expression Host: A Survey of Available Protein Production Platforms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 896:15-24. [PMID: 27165316 DOI: 10.1007/978-3-319-27216-0_2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Recombinant overexpression of a protein or a protein complex using any specific heterologous host can be an overwhelming challenge. The reasons may range from low yield and poor solubility of a single-subunit enzyme to the wrong stoichiometry or the incomplete assembly of a multiprotein complex. Whatever the reason, overcoming the difficulties will take the researcher into a journey through the seemingly countless options that exist for protein expression. While some choices stand to reason fairly straightforwardly (e.g., using Escherichia coli for the production of bacterial enzymes), most other choices do not need to be so self-revealing. Here, we attempt to portrait the canvas of available hosts for heterologous expression of many different protein classes and complexes and offer guidance as to which expression host may be more suitable to the problem at hand. The guidance in this chapter must be taken only as a rough indication which will have to be checked against the available literature and corroborated by experiment. It is not only expected but also welcome that, as more knowledge is gathered about the performance of hosts and protein types and new expression systems develop, the information in this chapter will have to be updated and refined.
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Affiliation(s)
- Francisco J Fernández
- Center for Biological Research, Spanish National Research Council (CIB-CSIC), Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - M Cristina Vega
- Center for Biological Research, Spanish National Research Council (CIB-CSIC), Ramiro de Maeztu 9, 28040, Madrid, Spain.
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34
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Ferrer M, Martínez-Martínez M, Bargiela R, Streit WR, Golyshina OV, Golyshin PN. Estimating the success of enzyme bioprospecting through metagenomics: current status and future trends. Microb Biotechnol 2016; 9:22-34. [PMID: 26275154 PMCID: PMC4720405 DOI: 10.1111/1751-7915.12309] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 06/26/2015] [Accepted: 07/02/2015] [Indexed: 12/01/2022] Open
Abstract
Recent reports have suggested that the establishment of industrially relevant enzyme collections from environmental genomes has become a routine procedure. Across the studies assessed, a mean number of approximately 44 active clones were obtained in an average size of approximately 53,000 clones tested using naïve screening protocols. This number could be significantly increased in shorter times when novel metagenome enzyme sequences obtained by direct sequencing are selected and subjected to high-throughput expression for subsequent production and characterization. The pre-screening of clone libraries by naïve screens followed by the pyrosequencing of the inserts allowed for a 106-fold increase in the success rate of identifying genes encoding enzymes of interest. However, a much longer time, usually on the order of years, is needed from the time of enzyme identification to the establishment of an industrial process. If the hit frequency for the identification of enzymes performing at high turnover rates under real application conditions could be increased while still covering a high natural diversity, the very expensive and time-consuming enzyme optimization phase would likely be significantly shortened. At this point, it is important to review the current knowledge about the success of fine-tuned naïve- and sequence-based screening protocols for enzyme selection and to describe the environments worldwide that have already been subjected to enzyme screen programmes through metagenomic tools. Here, we provide such estimations and suggest the current challenges and future actions needed before environmental enzymes can be successfully introduced into the market.
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Affiliation(s)
- Manuel Ferrer
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Mónica Martínez-Martínez
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Rafael Bargiela
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Wolfgang R Streit
- Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststraße 18, D-22609, Hamburg, Germany
| | - Olga V Golyshina
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
| | - Peter N Golyshin
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
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35
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Contemporary molecular tools in microbial ecology and their application to advancing biotechnology. Biotechnol Adv 2015; 33:1755-73. [DOI: 10.1016/j.biotechadv.2015.09.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 09/19/2015] [Accepted: 09/20/2015] [Indexed: 12/30/2022]
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36
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Lam KN, Cheng J, Engel K, Neufeld JD, Charles TC. Current and future resources for functional metagenomics. Front Microbiol 2015; 6:1196. [PMID: 26579102 PMCID: PMC4625089 DOI: 10.3389/fmicb.2015.01196] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/14/2015] [Indexed: 11/18/2022] Open
Abstract
Functional metagenomics is a powerful experimental approach for studying gene function, starting from the extracted DNA of mixed microbial populations. A functional approach relies on the construction and screening of metagenomic libraries—physical libraries that contain DNA cloned from environmental metagenomes. The information obtained from functional metagenomics can help in future annotations of gene function and serve as a complement to sequence-based metagenomics. In this Perspective, we begin by summarizing the technical challenges of constructing metagenomic libraries and emphasize their value as resources. We then discuss libraries constructed using the popular cloning vector, pCC1FOS, and highlight the strengths and shortcomings of this system, alongside possible strategies to maximize existing pCC1FOS-based libraries by screening in diverse hosts. Finally, we discuss the known bias of libraries constructed from human gut and marine water samples, present results that suggest bias may also occur for soil libraries, and consider factors that bias metagenomic libraries in general. We anticipate that discussion of current resources and limitations will advance tools and technologies for functional metagenomics research.
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Affiliation(s)
- Kathy N Lam
- Department of Biology, University of Waterloo Waterloo, ON, Canada
| | - Jiujun Cheng
- Department of Biology, University of Waterloo Waterloo, ON, Canada
| | - Katja Engel
- Department of Biology, University of Waterloo Waterloo, ON, Canada
| | - Josh D Neufeld
- Department of Biology, University of Waterloo Waterloo, ON, Canada
| | - Trevor C Charles
- Department of Biology, University of Waterloo Waterloo, ON, Canada
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Leis B, Heinze S, Angelov A, Pham VTT, Thürmer A, Jebbar M, Golyshin PN, Streit WR, Daniel R, Liebl W. Functional Screening of Hydrolytic Activities Reveals an Extremely Thermostable Cellulase from a Deep-Sea Archaeon. Front Bioeng Biotechnol 2015; 3:95. [PMID: 26191525 PMCID: PMC4486847 DOI: 10.3389/fbioe.2015.00095] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 06/17/2015] [Indexed: 01/27/2023] Open
Abstract
Extreme habitats serve as a source of enzymes that are active under extreme conditions and are candidates for industrial applications. In this work, six large-insert mixed genomic libraries were screened for hydrolase activities in a broad temperature range (8-70°C). Among a variety of hydrolytic activities, one fosmid clone, derived from a library of pooled isolates of hyperthermophilic archaea from deep sea vents, displayed hydrolytic activity on carboxymethyl cellulose substrate plates at 70°C but not at lower temperatures. Sequence analysis of the fosmid insert revealed a gene encoding a novel glycoside hydrolase family 12 (GHF12) endo-1,4-β-glucanase, termed Cel12E. The enzyme shares 45% sequence identity with a protein from the archaeon Thermococcus sp. AM4 and displays a unique multidomain architecture. Biochemical characterization of Cel12E revealed a remarkably thermostable protein, which appears to be of archaeal origin. The enzyme displayed maximum activity at 92°C and was active on a variety of linear 1,4-β-glucans like carboxymethyl cellulose, β-glucan, lichenan, and phosphoric acid swollen cellulose. The protein is able to bind to various insoluble β-glucans. Product pattern analysis indicated that Cel12E is an endo-cleaving β-glucanase. Cel12E expands the toolbox of hyperthermostable archaeal cellulases with biotechnological potential.
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Affiliation(s)
- Benedikt Leis
- Department of Microbiology, School of Life Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
| | - Simon Heinze
- Department of Microbiology, School of Life Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
| | - Angel Angelov
- Department of Microbiology, School of Life Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
| | - Vu Thuy Trang Pham
- Department of Microbiology, School of Life Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
| | - Andrea Thürmer
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Georg-August University Göttingen, Göttingen, Germany
| | - Mohamed Jebbar
- Laboratoire de Microbiologie des Environnements Extrêmes-UMR 6197 (CNRS-Ifremer-UBO), Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, Plouzané, France
| | | | - Wolfgang R. Streit
- Fakultät für Mathematik, Informatik und Naturwissenschaften Biologie, Biozentrum Klein Flottbek, Universität Hamburg, Hamburg, Germany
| | - Rolf Daniel
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Georg-August University Göttingen, Göttingen, Germany
| | - Wolfgang Liebl
- Department of Microbiology, School of Life Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
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Pseudomonas putida-a versatile host for the production of natural products. Appl Microbiol Biotechnol 2015; 99:6197-214. [PMID: 26099332 PMCID: PMC4495716 DOI: 10.1007/s00253-015-6745-4] [Citation(s) in RCA: 170] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 05/26/2015] [Accepted: 05/29/2015] [Indexed: 10/30/2022]
Abstract
The biosynthesis of natural products by heterologous expression of biosynthetic pathways in amenable production strains enables biotechnological access to a variety of valuable compounds by conversion of renewable resources. Pseudomonas putida has emerged as a microbial laboratory work horse, with elaborated techniques for cultivation and genetic manipulation available. Beyond that, this bacterium offers several particular advantages with regard to natural product biosynthesis, notably a versatile intrinsic metabolism with diverse enzymatic capacities as well as an outstanding tolerance to xenobiotics. Therefore, it has been applied for recombinant biosynthesis of several valuable natural products. This review provides an overview of applications of P. putida as a host organism for the recombinant biosynthesis of such natural products, including rhamnolipids, terpenoids, polyketides and non-ribosomal peptides, and other amino acid-derived compounds. The focus is on de novo natural product synthesis from intrinsic building blocks by means of heterologous gene expression and strain engineering. Finally, the future potential of the bacterium as a chassis organism for synthetic microbiology is pointed out.
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Elleuche S, Schäfers C, Blank S, Schröder C, Antranikian G. Exploration of extremophiles for high temperature biotechnological processes. Curr Opin Microbiol 2015; 25:113-9. [PMID: 26066287 DOI: 10.1016/j.mib.2015.05.011] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 04/08/2015] [Accepted: 05/15/2015] [Indexed: 01/17/2023]
Abstract
Industrial processes often take place under harsh conditions that are hostile to microorganisms and their biocatalysts. Microorganisms surviving at temperatures above 60°C represent a chest of biotechnological treasures for high-temperature bioprocesses by producing a large portfolio of biocatalysts (thermozymes). Due to the unique requirements to cultivate thermophilic (60-80°C) and hyperthermophilic (80-110°C) Bacteria and Archaea, less than 5% are cultivable in the laboratory. Therefore, other approaches including sequence-based screenings and metagenomics have been successful in providing novel thermozymes. In particular, polysaccharide-degrading enzymes (amylolytic enzymes, hemicellulases, cellulases, pectinases and chitinases), lipolytic enzymes and proteases from thermophiles have attracted interest due to their potential for versatile applications in pharmaceutical, chemical, food, textile, paper, leather and feed industries as well as in biorefineries.
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Affiliation(s)
- Skander Elleuche
- Institute of Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, D-21073 Hamburg, Germany
| | - Christian Schäfers
- Institute of Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, D-21073 Hamburg, Germany
| | - Saskia Blank
- Institute of Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, D-21073 Hamburg, Germany
| | - Carola Schröder
- Institute of Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, D-21073 Hamburg, Germany
| | - Garabed Antranikian
- Institute of Technical Microbiology, Hamburg University of Technology (TUHH), Kasernenstr. 12, D-21073 Hamburg, Germany.
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40
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Cheng D, Wang R, Prather KJ, Chow KL, Hsing IM. Tackling codon usage bias for heterologous expression in Rhodobacter sphaeroides by supplementation of rare tRNAs. Enzyme Microb Technol 2015; 72:25-34. [DOI: 10.1016/j.enzmictec.2015.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 02/05/2015] [Accepted: 02/07/2015] [Indexed: 10/24/2022]
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41
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Leis B, Angelov A, Mientus M, Li H, Pham VTT, Lauinger B, Bongen P, Pietruszka J, Gonçalves LG, Santos H, Liebl W. Identification of novel esterase-active enzymes from hot environments by use of the host bacterium Thermus thermophilus. Front Microbiol 2015; 6:275. [PMID: 25904908 PMCID: PMC4389547 DOI: 10.3389/fmicb.2015.00275] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/19/2015] [Indexed: 01/27/2023] Open
Abstract
Functional metagenomic screening strategies, which are independent of known sequence information, can lead to the identification of truly novel genes and enzymes. Since E. coli has been used exhaustively for this purpose as a host, it is important to establish alternative expression hosts and to use them for functional metagenomic screening for new enzymes. In this study we show that Thermus thermophilus HB27 is an excellent screening host and can be used as an alternative provider of truly novel biocatalysts. In a previous study we constructed mutant strain BL03 with multiple markerless deletions in genes for major extra- and intracellular lipolytic activities. This esterase-diminished strain was no longer able to grow on defined minimal medium supplemented with tributyrin as the sole carbon source and could be used as a host to screen for metagenomic DNA fragments that could complement growth on tributyrin. Several thousand single fosmid clones from thermophilic metagenomic libraries from heated compost and hot spring water samples were subjected to a comparative screening for esterase activity in both T. thermophilus strain BL03 and E. coli EPI300. We scored a greater number of active esterase clones in the thermophilic bacterium than in the mesophilic E. coli. From several thousand functionally screened clones only two thermostable α/β-fold hydrolase enzymes with high amino acid sequence similarity to already characterized enzymes were identifiable in E. coli. In contrast, five further fosmids were found that conferred lipolytic activities in T. thermophilus only. Four open reading frames (ORFs) were found which did not share significant similarity to known esterase enzymes but contained the conserved GXSXG motif regularly found in lipolytic enzymes. Two of the genes were expressed in both hosts and the novel thermophilic esterases, which based on their primary structures could not be assigned to known esterase or lipase families, were purified and preliminarily characterized. Our work underscores the benefit of using additional screening hosts other than E. coli for the identification of novel biocatalysts with industrial relevance.
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Affiliation(s)
- Benedikt Leis
- Department of Microbiology, Technische Universität München Freising, Germany
| | - Angel Angelov
- Department of Microbiology, Technische Universität München Freising, Germany
| | - Markus Mientus
- Department of Microbiology, Technische Universität München Freising, Germany
| | - Haijuan Li
- Department of Microbiology, Technische Universität München Freising, Germany
| | - Vu T T Pham
- Department of Microbiology, Technische Universität München Freising, Germany
| | - Benjamin Lauinger
- Research Center Juelich, Institute of Bioorganic Chemistry, Heinrich-Heine-Universität Düsseldorf Juelich, Germany
| | - Patrick Bongen
- Research Center Juelich, Institute of Bioorganic Chemistry, Heinrich-Heine-Universität Düsseldorf Juelich, Germany
| | - Jörg Pietruszka
- Research Center Juelich, Institute of Bioorganic Chemistry, Heinrich-Heine-Universität Düsseldorf Juelich, Germany
| | - Luís G Gonçalves
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa Oeiras, Portugal
| | - Helena Santos
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa Oeiras, Portugal
| | - Wolfgang Liebl
- Department of Microbiology, Technische Universität München Freising, Germany
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Fouhy F, Stanton C, Cotter PD, Hill C, Walsh F. Proteomics as the final step in the functional metagenomics study of antimicrobial resistance. Front Microbiol 2015; 6:172. [PMID: 25784907 PMCID: PMC4347484 DOI: 10.3389/fmicb.2015.00172] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/15/2015] [Indexed: 01/23/2023] Open
Abstract
The majority of clinically applied antimicrobial agents are derived from natural products generated by soil microorganisms and therefore resistance is likely to be ubiquitous in such environments. This is supported by the fact that numerous clinically important resistance mechanisms are encoded within the genomes of such bacteria. Advances in genomic sequencing have enabled the in silico identification of putative resistance genes present in these microorganisms. However, it is not sufficient to rely on the identification of putative resistance genes, we must also determine if the resultant proteins confer a resistant phenotype. This will require an analysis pipeline that extends from the extraction of environmental DNA, to the identification and analysis of potential resistance genes and their resultant proteins and phenotypes. This review focuses on the application of functional metagenomics and proteomics to study antimicrobial resistance in diverse environments.
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Affiliation(s)
- Fiona Fouhy
- Teagasc - Moorepark Food Research Centre , Fermoy, Ireland
| | - Catherine Stanton
- Teagasc - Moorepark Food Research Centre , Fermoy, Ireland ; Alimentary Pharmabiotic Centre , Cork, Ireland
| | - Paul D Cotter
- Teagasc - Moorepark Food Research Centre , Fermoy, Ireland ; Alimentary Pharmabiotic Centre , Cork, Ireland
| | - Colin Hill
- Alimentary Pharmabiotic Centre , Cork, Ireland ; School of Microbiology, University College Cork , Cork, Ireland
| | - Fiona Walsh
- Department of Biology, National University of Ireland Maynooth , Maynooth, Ireland
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Vester JK, Glaring MA, Stougaard P. Improved cultivation and metagenomics as new tools for bioprospecting in cold environments. Extremophiles 2014; 19:17-29. [PMID: 25399309 PMCID: PMC4272415 DOI: 10.1007/s00792-014-0704-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 10/28/2014] [Indexed: 11/28/2022]
Abstract
Only a small minority of microorganisms from an environmental sample can be cultured in the laboratory leaving the enormous bioprospecting potential of the uncultured diversity unexplored. This resource can be accessed by improved cultivation methods in which the natural environment is brought into the laboratory or through metagenomic approaches where culture-independent DNA sequence information can be combined with functional screening. The coupling of these two approaches circumvents the need for pure, cultured isolates and can be used to generate targeted information on communities enriched for specific activities or properties. Bioprospecting in extreme environments is often associated with additional challenges such as low biomass, slow cell growth, complex sample matrices, restricted access, and problematic in situ analyses. In addition, the choice of vector system and expression host may be limited as few hosts are available for expression of genes with extremophilic properties. This review summarizes the methods developed for improved cultivation as well as the metagenomic approaches for bioprospecting with focus on the challenges faced by bioprospecting in cold environments.
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Affiliation(s)
- Jan Kjølhede Vester
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark,
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