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Köbbing S, Lechtenberg T, Wynands B, Blank LM, Wierckx N. Reliable Genomic Integration Sites in Pseudomonas putida Identified by Two-Dimensional Transcriptome Analysis. ACS Synth Biol 2024. [PMID: 38968167 DOI: 10.1021/acssynbio.3c00747] [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: 07/07/2024]
Abstract
Genomic integration is commonly used to engineer stable production hosts. However, so far, for many microbial workhorses, only a few integration sites have been characterized, thereby restraining advanced strain engineering that requires multiple insertions. Here, we report on the identification of novel genomic integration sites, so-called landing pads, for Pseudomonas putida KT2440. We identified genomic regions with constant expression patterns under diverse experimental conditions by using RNA-Seq data. Homologous recombination constructs were designed to insert heterologous genes into intergenic sites in these regions, allowing condition-independent gene expression. Ten potential landing pads were characterized using four different msfGFP expression cassettes. An insulated probe sensor was used to study locus-dependent effects on recombinant gene expression, excluding genomic read-through of flanking promoters under changing cultivation conditions. While the reproducibility of expression in the landing pads was very high, the msfGFP signals varied strongly between the different landing pads, confirming a strong influence of the genomic context. To showcase that the identified landing pads are also suitable candidates for heterologous gene expression in other Pseudomonads, four equivalent landing pads were identified and characterized in Pseudomonas taiwanensis VLB120. This study shows that genomic "hot" and "cold" spots exist, causing strong promoter-independent variations in gene expression. This highlights that the genomic context is an additional parameter to consider when designing integrable genomic cassettes for tailored heterologous expression. The set of characterized genomic landing pads presented here further increases the genetic toolbox for deep metabolic engineering in Pseudomonads.
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Affiliation(s)
- Sebastian Köbbing
- Aachen Biology and Biotechnology-ABBt, Institute of Applied Microbiology-iAMB, RWTH Aachen University, 52074 Aachen, Germany
| | - Thorsten Lechtenberg
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Benedikt Wynands
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Lars M Blank
- Aachen Biology and Biotechnology-ABBt, Institute of Applied Microbiology-iAMB, RWTH Aachen University, 52074 Aachen, Germany
| | - Nick Wierckx
- Aachen Biology and Biotechnology-ABBt, Institute of Applied Microbiology-iAMB, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52428 Jülich, Germany
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2
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Bitzenhofer NL, Höfel C, Thies S, Weiler AJ, Eberlein C, Heipieper HJ, Batra‐Safferling R, Sundermeyer P, Heidler T, Sachse C, Busche T, Kalinowski J, Belthle T, Drepper T, Jaeger K, Loeschcke A. Exploring engineered vesiculation by Pseudomonas putida KT2440 for natural product biosynthesis. Microb Biotechnol 2024; 17:e14312. [PMID: 37435812 PMCID: PMC10832525 DOI: 10.1111/1751-7915.14312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 06/25/2023] [Indexed: 07/13/2023] Open
Abstract
Pseudomonas species have become promising cell factories for the production of natural products due to their inherent robustness. Although these bacteria have naturally evolved strategies to cope with different kinds of stress, many biotechnological applications benefit from engineering of optimised chassis strains with specially adapted tolerance traits. Here, we explored the formation of outer membrane vesicles (OMV) of Pseudomonas putida KT2440. We found OMV production to correlate with the recombinant production of a natural compound with versatile beneficial properties, the tripyrrole prodigiosin. Further, several P. putida genes were identified, whose up- or down-regulated expression allowed controlling OMV formation. Finally, genetically triggering vesiculation in production strains of the different alkaloids prodigiosin, violacein, and phenazine-1-carboxylic acid, as well as the carotenoid zeaxanthin, resulted in up to three-fold increased product yields. Consequently, our findings suggest that the construction of robust strains by genetic manipulation of OMV formation might be developed into a useful tool which may contribute to improving limited biotechnological applications.
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Affiliation(s)
- Nora Lisa Bitzenhofer
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
| | - Carolin Höfel
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
| | - Stephan Thies
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
| | - Andrea Jeanette Weiler
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
| | - Christian Eberlein
- Department of Environmental BiotechnologyHelmholtz Centre for Environmental Research (UFZ)LeipzigGermany
| | - Hermann J. Heipieper
- Department of Environmental BiotechnologyHelmholtz Centre for Environmental Research (UFZ)LeipzigGermany
| | - Renu Batra‐Safferling
- Institute of Biological Information Processing – Structural Biochemistry (IBI‐7: Structural Biochemistry)Forschungszentrum JülichJülichGermany
| | - Pia Sundermeyer
- Ernst‐Ruska Centre for Microscopy and Spectroscopy with Electrons (ER‐C‐3/Structural Biology)Forschungszentrum JülichJülichGermany
- Institute for Biological Information Processing 6 (IBI‐6/ Structural Cellular Biology)Forschungszentrum JülichJülichGermany
| | - Thomas Heidler
- Ernst‐Ruska Centre for Microscopy and Spectroscopy with Electrons (ER‐C‐3/Structural Biology)Forschungszentrum JülichJülichGermany
- Institute for Biological Information Processing 6 (IBI‐6/ Structural Cellular Biology)Forschungszentrum JülichJülichGermany
| | - Carsten Sachse
- Ernst‐Ruska Centre for Microscopy and Spectroscopy with Electrons (ER‐C‐3/Structural Biology)Forschungszentrum JülichJülichGermany
- Institute for Biological Information Processing 6 (IBI‐6/ Structural Cellular Biology)Forschungszentrum JülichJülichGermany
- Department of BiologyHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec)Bielefeld UniversityBielefeldGermany
- Bielefeld University, Medical School East Westphalia‐LippeBielefeld UniversityBielefeldGermany
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec)Bielefeld UniversityBielefeldGermany
| | - Thomke Belthle
- DWI─Leibniz‐Institute for Interactive MaterialsAachenGermany
- Functional and Interactive Polymers, Institute of Technical and Macromolecular ChemistryRWTH Aachen UniversityAachenGermany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
| | - Karl‐Erich Jaeger
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
- Institute of Bio‐ and Geosciences IBG‐1: BiotechnologyForschungszentrum JülichJülichGermany
| | - Anita Loeschcke
- Institute of Molecular Enzyme Technology (IMET)Heinrich Heine University DüsseldorfDüsseldorfGermany
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3
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Hueso-Gil A, Calles B, de Lorenzo V. In Vivo Sampling of Intracellular Heterogeneity of Pseudomonas putida Enables Multiobjective Optimization of Genetic Devices. ACS Synth Biol 2023; 12:1667-1676. [PMID: 37196337 PMCID: PMC10278179 DOI: 10.1021/acssynbio.3c00009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Indexed: 05/19/2023]
Abstract
The inner physicochemical heterogeneity of bacterial cells generates three-dimensional (3D)-dependent variations of resources for effective expression of given chromosomally located genes. This fact has been exploited for adjusting the most favorable parameters for implanting a complex device for optogenetic control of biofilm formation in the soil bacterium Pseudomonas putida. To this end, a DNA segment encoding a superactive variant of the Caulobacter crescendus diguanylate cyclase PleD expressed under the control of the cyanobacterial light-responsive CcaSR system was placed in a mini-Tn5 transposon vector and randomly inserted through the chromosome of wild-type and biofilm-deficient variants of P. putida lacking the wsp gene cluster. This operation delivered a collection of clones covering a whole range of biofilm-building capacities and dynamic ranges in response to green light. Since the phenotypic output of the device depends on a large number of parameters (multiple promoters, RNA stability, translational efficacy, metabolic precursors, protein folding, etc.), we argue that random chromosomal insertions enable sampling the intracellular milieu for an optimal set of resources that deliver a preset phenotypic specification. Results thus support the notion that the context dependency can be exploited as a tool for multiobjective optimization, rather than a foe to be suppressed in Synthetic Biology constructs.
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Affiliation(s)
| | - Belén Calles
- Systems Biology Department, Centro Nacional de Biotecnología-CSIC, Campus
de Cantoblanco, Madrid 28049, Spain
| | - Víctor de Lorenzo
- Systems Biology Department, Centro Nacional de Biotecnología-CSIC, Campus
de Cantoblanco, Madrid 28049, Spain
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Luo ZW, Choi KR, Lee SY. Improved terephthalic acid production from p-xylene using metabolically engineered Pseudomonas putida. Metab Eng 2023; 76:75-86. [PMID: 36693471 DOI: 10.1016/j.ymben.2023.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/10/2023] [Accepted: 01/20/2023] [Indexed: 01/22/2023]
Abstract
Terephthalic acid (TPA) is an important commodity chemical used as a monomer of polyethylene terephthalate (PET). Since a large quantity of PET is routinely manufactured and consumed worldwide, the development of sustainable biomanufacturing processes for its monomers (i.e. TPA and ethylene glycol) has recently gained much attention. In a previous study, we reported the development of a metabolically engineered Escherichia coli strain producing 6.7 g/L of TPA from p-xylene (pX) with a productivity and molar conversion yield of 0.278 g/L/h and 96.7 mol%, respectively. Here, we report metabolic engineering of Pseudomonas putida KT2440, a microbial chassis particularly suitable for the synthesis of aromatic compounds, for improved biocatalytic conversion of pX to TPA. To develop a plasmid-free, antibiotic-free, and inducer-free biocatalytic process for cost-competitive TPA production, all heterologous genes required for the synthetic pX-to-TPA bioconversion pathway were integrated into the chromosome of P. putida KT2440 by RecET-based markerless recombineering and overexpressed under the control of constitutive promoters. Next, TPA production was enhanced by integrating multiple copies of the heterologous genes to the ribosomal RNA genes through iteration of recombineering-based random integration and subsequent screening of high-performance strains. Finally, fed-batch fermentation process was optimized to further improve the performance of the engineered P. putida strain. As a result, 38.25 ± 0.11 g/L of TPA was produced from pX with a molar conversion yield of 99.6 ± 0.6%, which is equivalent to conversion of 99.3 ± 0.8 g pX to 154.6 ± 0.5 g TPA. This superior pX-to-TPA biotransformation process based on the engineered P. putida strain will pave the way to the commercial biomanufacturing of TPA in an industrial scale.
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Affiliation(s)
- Zi Wei Luo
- Metabolic and Biomolecular Engineering National Research Laboratory and Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea; BioProcess Engineering Research Center, KAIST, Daejeon, 34141, Republic of Korea
| | - Kyeong Rok Choi
- Metabolic and Biomolecular Engineering National Research Laboratory and Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea; BioProcess Engineering Research Center, KAIST, Daejeon, 34141, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory and Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea; BioProcess Engineering Research Center, KAIST, Daejeon, 34141, Republic of Korea; BioInformatics Research Center, KAIST Institute for the BioCentury, and KAIST Institute for Artificial Intelligence, KAIST, Daejeon, 34141, Republic of Korea.
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5
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Kossmann DF, Huang M, Weihmann R, Xiao X, Gätgens F, Weber TM, Brass HUC, Bitzenhofer NL, Ibrahim S, Bangert K, Rehling L, Mueller C, Tiso T, Blank LM, Drepper T, Jaeger KE, Grundler FMW, Pietruszka J, Schleker ASS, Loeschcke A. Production of tailored hydroxylated prodiginine showing combinatorial activity with rhamnolipids against plant-parasitic nematodes. Front Microbiol 2023; 14:1151882. [PMID: 37200918 PMCID: PMC10187637 DOI: 10.3389/fmicb.2023.1151882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/03/2023] [Indexed: 05/20/2023] Open
Abstract
Bacterial secondary metabolites exhibit diverse remarkable bioactivities and are thus the subject of study for different applications. Recently, the individual effectiveness of tripyrrolic prodiginines and rhamnolipids against the plant-parasitic nematode Heterodera schachtii, which causes tremendous losses in crop plants, was described. Notably, rhamnolipid production in engineered Pseudomonas putida strains has already reached industrial implementation. However, the non-natural hydroxyl-decorated prodiginines, which are of particular interest in this study due to a previously described particularly good plant compatibility and low toxicity, are not as readily accessible. In the present study, a new effective hybrid synthetic route was established. This included the engineering of a novel P. putida strain to provide enhanced levels of a bipyrrole precursor and an optimization of mutasynthesis, i.e., the conversion of chemically synthesized and supplemented monopyrroles to tripyrrolic compounds. Subsequent semisynthesis provided the hydroxylated prodiginine. The prodiginines caused reduced infectiousness of H. schachtii for Arabidopsis thaliana plants resulting from impaired motility and stylet thrusting, providing the first insights on the mode of action in this context. Furthermore, the combined application with rhamnolipids was assessed for the first time and found to be more effective against nematode parasitism than the individual compounds. To obtain, for instance, 50% nematode control, it was sufficient to apply 7.8 μM hydroxylated prodiginine together with 0.7 μg/ml (~ 1.1 μM) di-rhamnolipids, which corresponded to ca. ¼ of the individual EC50 values. In summary, a hybrid synthetic route toward a hydroxylated prodiginine was established and its effects and combinatorial activity with rhamnolipids on plant-parasitic nematode H. schachtii are presented, demonstrating potential application as antinematodal agents. Graphical Abstract.
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Affiliation(s)
- D. F. Kossmann
- Institute of Bio- and Geosciences (IBG-1): Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bioorganic Chemistry, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - M. Huang
- INRES, Molecular Phytomedicine, University of Bonn, Bonn, Germany
| | - R. Weihmann
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - X. Xiao
- INRES, Molecular Phytomedicine, University of Bonn, Bonn, Germany
| | - F. Gätgens
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - T. M. Weber
- Institute of Bioorganic Chemistry, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - H. U. C. Brass
- Institute of Bioorganic Chemistry, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - N. L. Bitzenhofer
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - S. Ibrahim
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - K. Bangert
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - L. Rehling
- INRES, Molecular Phytomedicine, University of Bonn, Bonn, Germany
| | - C. Mueller
- iAMB—Institute of Applied Microbiology, ABBt—Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - T. Tiso
- iAMB—Institute of Applied Microbiology, ABBt—Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - L. M. Blank
- iAMB—Institute of Applied Microbiology, ABBt—Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - T. Drepper
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - K.-E. Jaeger
- Institute of Bio- and Geosciences (IBG-1): Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
| | | | - J. Pietruszka
- Institute of Bio- and Geosciences (IBG-1): Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bioorganic Chemistry, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
- *Correspondence: J. Pietruszka,
| | - A. S. S. Schleker
- INRES, Molecular Phytomedicine, University of Bonn, Bonn, Germany
- A. S. S. Schleker,
| | - A. Loeschcke
- Institute of Molecular Enzyme Technology, Forschungszentrum Jülich, Heinrich Heine University Düsseldorf, Jülich, Germany
- A. Loeschcke,
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6
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Weihmann R, Kubicki S, Bitzenhofer NL, Domröse A, Bator I, Kirschen LM, Kofler F, Funk A, Tiso T, Blank LM, Jaeger KE, Drepper T, Thies S, Loeschcke A. The modular pYT vector series employed for chromosomal gene integration and expression to produce carbazoles and glycolipids in P. putida. FEMS MICROBES 2022; 4:xtac030. [PMID: 37333445 PMCID: PMC10117823 DOI: 10.1093/femsmc/xtac030] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 11/03/2022] [Accepted: 12/16/2022] [Indexed: 10/22/2023] Open
Abstract
The expression of biosynthetic genes in bacterial hosts can enable access to high-value compounds, for which appropriate molecular genetic tools are essential. Therefore, we developed a toolbox of modular vectors, which facilitate chromosomal gene integration and expression in Pseudomonas putida KT2440. To this end, we designed an integrative sequence, allowing customisation regarding the modes of integration (random, at attTn7, or into the 16S rRNA gene), promoters, antibiotic resistance markers as well as fluorescent proteins and enzymes as transcription reporters. We thus established a toolbox of vectors carrying integrative sequences, designated as pYT series, of which we present 27 ready-to-use variants along with a set of strains equipped with unique 'landing pads' for directing a pYT interposon into one specific copy of the 16S rRNA gene. We used genes of the well-described violacein biosynthesis as reporter to showcase random Tn5-based chromosomal integration leading to constitutive expression and production of violacein and deoxyviolacein. Deoxyviolacein was likewise produced after gene integration into the 16S rRNA gene of rrn operons. Integration in the attTn7 site was used to characterise the suitability of different inducible promoters and successive strain development for the metabolically challenging production of mono-rhamnolipids. Finally, to establish arcyriaflavin A production in P. putida for the first time, we compared different integration and expression modes, revealing integration at attTn7 and expression with NagR/PnagAa to be most suitable. In summary, the new toolbox can be utilised for the rapid generation of various types of P. putida expression and production strains.
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Affiliation(s)
- Robin Weihmann
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Sonja Kubicki
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nora Lisa Bitzenhofer
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Andreas Domröse
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Isabel Bator
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
| | - Lisa-Marie Kirschen
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Franziska Kofler
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Aileen Funk
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Till Tiso
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
| | - Lars M Blank
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Institute of Bio-and Geosciences IBG 1: Biotechnology, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Stephan Thies
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Anita Loeschcke
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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7
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Bernhards CB, Liem AT, Berk KL, Roth PA, Gibbons HS, Lux MW. Putative Phenotypically Neutral Genomic Insertion Points in Prokaryotes. ACS Synth Biol 2022; 11:1681-1685. [PMID: 35271248 PMCID: PMC9016761 DOI: 10.1021/acssynbio.1c00531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
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The barriers to effective
genome editing in diverse prokaryotic
organisms have been falling at an accelerated rate. As editing becomes
easier in more organisms, quickly identifying genomic locations to
insert new genetic functions without disrupting organism fitness becomes
increasingly useful. When the insertion is noncoding DNA for applications
such as information storage or barcoding, a neutral insertion point
can be especially important. Here we describe an approach to identify
putatively neutral insertion sites in prokaryotes. An algorithm (targetFinder)
finds convergently transcribed genes with gap sizes within a specified
range, and looks for annotations within the gaps. We report putative
editing targets for 10 common synthetic biology chassis organisms,
including coverage of available RNA-seq data, and provide software
to apply to others. We further experimentally evaluate the neutrality
of six identified targets in Escherichia coli through
insertion of a DNA barcode. We anticipate this information and the
accompanying tool will prove useful for synthetic biologists seeking
neutral insertion points for genome editing.
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Affiliation(s)
- Casey B. Bernhards
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
- Excet, Inc., Springfield, Virginia 22150, United States
| | - Alvin T. Liem
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
- DCS Corporation, Belcamp, Maryland 21017, United States
| | - Kimberly L. Berk
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
| | - Pierce A. Roth
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
- DCS Corporation, Belcamp, Maryland 21017, United States
| | - Henry S. Gibbons
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
| | - Matthew W. Lux
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010, United States
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9
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Towards robust Pseudomonas cell factories to harbour novel biosynthetic pathways. Essays Biochem 2021; 65:319-336. [PMID: 34223620 PMCID: PMC8314020 DOI: 10.1042/ebc20200173] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 05/01/2021] [Accepted: 05/24/2021] [Indexed: 02/07/2023]
Abstract
Biotechnological production in bacteria enables access to numerous valuable chemical compounds. Nowadays, advanced molecular genetic toolsets, enzyme engineering as well as the combinatorial use of biocatalysts, pathways, and circuits even bring new-to-nature compounds within reach. However, the associated substrates and biosynthetic products often cause severe chemical stress to the bacterial hosts. Species of the Pseudomonas clade thus represent especially valuable chassis as they are endowed with multiple stress response mechanisms, which allow them to cope with a variety of harmful chemicals. A built-in cell envelope stress response enables fast adaptations that sustain membrane integrity under adverse conditions. Further, effective export machineries can prevent intracellular accumulation of diverse harmful compounds. Finally, toxic chemicals such as reactive aldehydes can be eliminated by oxidation and stress-induced damage can be recovered. Exploiting and engineering these features will be essential to support an effective production of natural compounds and new chemicals. In this article, we therefore discuss major resistance strategies of Pseudomonads along with approaches pursued for their targeted exploitation and engineering in a biotechnological context. We further highlight strategies for the identification of yet unknown tolerance-associated genes and their utilisation for engineering next-generation chassis and finally discuss effective measures for pathway fine-tuning to establish stable cell factories for the effective production of natural compounds and novel biochemicals.
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10
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Subcellular Architecture of the xyl Gene Expression Flow of the TOL Catabolic Plasmid of Pseudomonas putida mt-2. mBio 2021; 12:mBio.03685-20. [PMID: 33622725 PMCID: PMC8545136 DOI: 10.1128/mbio.03685-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Despite intensive research on the biochemical and regulatory features of the archetypal catabolic TOL system borne by pWW0 of Pseudomonas putida strain mt-2, the physical arrangement and tridimensional logic of the xyl gene expression flow remains unknown. In this work, the spatial distribution of specific xyl mRNAs with respect to the host nucleoid, the TOL plasmid, and the ribosomal pool has been investigated. In situ hybridization of target transcripts with fluorescent oligonucleotide probes revealed that xyl mRNAs cluster in discrete foci, adjacent but clearly separated from the TOL plasmid and the cell nucleoid. Also, they colocalize with ribosome-rich domains of the intracellular milieu. This arrangement was maintained even when the xyl genes were artificially relocated to different chromosomal locations. The same held true when genes were expressed through a heterologous T7 polymerase-based system, which likewise led to mRNA foci outside the DNA. In contrast, rifampin treatment, known to ease crowding, blurred the confinement of xyl transcripts. This suggested that xyl mRNAs exit from their initiation sites to move to ribosome-rich points for translation—rather than being translated coupled to transcription. Moreover, the results suggest the distinct subcellular motion of xyl mRNAs results from both innate properties of the sequences and the physical forces that keep the ribosomal pool away from the nucleoid in P. putida. This scenario is discussed within the background of current knowledge on the three-dimensional organization of the gene expression flow in other bacteria and the environmental lifestyle of this soil microorganism.
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Engineering Heterologous Hosts for the Enhanced Production of Non-ribosomal Peptides. BIOTECHNOL BIOPROC E 2021. [DOI: 10.1007/s12257-020-0080-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Weimer A, Kohlstedt M, Volke DC, Nikel PI, Wittmann C. Industrial biotechnology of Pseudomonas putida: advances and prospects. Appl Microbiol Biotechnol 2020; 104:7745-7766. [PMID: 32789744 PMCID: PMC7447670 DOI: 10.1007/s00253-020-10811-9] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/23/2020] [Accepted: 08/02/2020] [Indexed: 11/17/2022]
Abstract
Pseudomonas putida is a Gram-negative, rod-shaped bacterium that can be encountered in diverse ecological habitats. This ubiquity is traced to its remarkably versatile metabolism, adapted to withstand physicochemical stress, and the capacity to thrive in harsh environments. Owing to these characteristics, there is a growing interest in this microbe for industrial use, and the corresponding research has made rapid progress in recent years. Hereby, strong drivers are the exploitation of cheap renewable feedstocks and waste streams to produce value-added chemicals and the steady progress in genetic strain engineering and systems biology understanding of this bacterium. Here, we summarize the recent advances and prospects in genetic engineering, systems and synthetic biology, and applications of P. putida as a cell factory. KEY POINTS: • Pseudomonas putida advances to a global industrial cell factory. • Novel tools enable system-wide understanding and streamlined genomic engineering. • Applications of P. putida range from bioeconomy chemicals to biosynthetic drugs.
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Affiliation(s)
- Anna Weimer
- Institute of Systems Biotechnology, Saarland University, Campus A1.5, 66123, Saarbrücken, Germany
| | - Michael Kohlstedt
- Institute of Systems Biotechnology, Saarland University, Campus A1.5, 66123, Saarbrücken, Germany
| | - Daniel C Volke
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Pablo I Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Campus A1.5, 66123, Saarbrücken, Germany.
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Tiso T, Ihling N, Kubicki S, Biselli A, Schonhoff A, Bator I, Thies S, Karmainski T, Kruth S, Willenbrink AL, Loeschcke A, Zapp P, Jupke A, Jaeger KE, Büchs J, Blank LM. Integration of Genetic and Process Engineering for Optimized Rhamnolipid Production Using Pseudomonas putida. Front Bioeng Biotechnol 2020; 8:976. [PMID: 32974309 PMCID: PMC7468518 DOI: 10.3389/fbioe.2020.00976] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/27/2020] [Indexed: 12/27/2022] Open
Abstract
Rhamnolipids are biosurfactants produced by microorganisms with the potential to replace synthetic compounds with petrochemical origin. To promote industrial use of rhamnolipids, recombinant rhamnolipid production from sugars needs to be intensified. Since this remains challenging, the aim of the presented research is to utilize a multidisciplinary approach to take a step toward developing a sustainable rhamnolipid production process. Here, we developed expression cassettes for stable integration of the rhamnolipid biosynthesis genes into the genome outperformed plasmid-based expression systems. Furthermore, the genetic stability of the production strain was improved by using an inducible promoter. To enhance rhamnolipid synthesis, energy- and/or carbon-consuming traits were removed: mutants negative for the synthesis of the flagellar machinery or the storage polymer PHA showed increased production by 50%. Variation of time of induction resulted in an 18% increase in titers. A scale-up from shake flasks was carried out using a 1-L bioreactor. By recycling of the foam, biomass loss could be minimized and a rhamnolipid titer of up to 1.5 g/L was achieved without using mechanical foam destroyers or antifoaming agents. Subsequent liquid-liquid extraction was optimized by using a suitable minimal medium during fermentation to reduce undesired interphase formation. A technical-scale production process was designed and evaluated by a life-cycle assessment (LCA). Different process chains and their specific environmental impact were examined. It was found that next to biomass supply, the fermentation had the biggest environmental impact. The present work underlines the need for multidisciplinary approaches to address the challenges associated with achieving sustainable production of microbial secondary metabolites. The results are discussed in the context of the challenges of microbial biosurfactant production using hydrophilic substrates on an industrial scale.
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Affiliation(s)
- Till Tiso
- iAMB – Institute of Applied Microbiology, ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Nina Ihling
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Chair of Biochemical Engineering (AVT.BioVT), RWTH Aachen University, Aachen, Germany
| | - Sonja Kubicki
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Andreas Biselli
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Fluid Process Engineering (AVT.FVT), RWTH Aachen University, Aachen, Germany
| | - Andreas Schonhoff
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Energy and Climate Research – Systems Analysis and Technology Evaluation (IEK-STE), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Isabel Bator
- iAMB – Institute of Applied Microbiology, ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Stephan Thies
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Tobias Karmainski
- iAMB – Institute of Applied Microbiology, ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Sebastian Kruth
- iAMB – Institute of Applied Microbiology, ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Anna-Lena Willenbrink
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Fluid Process Engineering (AVT.FVT), RWTH Aachen University, Aachen, Germany
| | - Anita Loeschcke
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Petra Zapp
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Energy and Climate Research – Systems Analysis and Technology Evaluation (IEK-STE), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Andreas Jupke
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Fluid Process Engineering (AVT.FVT), RWTH Aachen University, Aachen, Germany
| | - Karl-Erich Jaeger
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
- Institute of Bio- and Geosciences IBG 1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Jochen Büchs
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
- Chair of Biochemical Engineering (AVT.BioVT), RWTH Aachen University, Aachen, Germany
| | - Lars M. Blank
- iAMB – Institute of Applied Microbiology, ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, Jülich, Germany
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Evaluation of chromosomal insertion loci in the Pseudomonas putida KT2440 genome for predictable biosystems design. Metab Eng Commun 2020; 11:e00139. [PMID: 32775199 PMCID: PMC7398981 DOI: 10.1016/j.mec.2020.e00139] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/02/2020] [Accepted: 07/15/2020] [Indexed: 01/27/2023] Open
Abstract
The development of Pseudomonas strains for industrial production of fuels and chemicals will require the integration of heterologous genes and pathways into the chromosome. Finding the most appropriate integration site to maximize strain performance is an essential part of the strain design process. We characterized seven chromosomal loci in Pseudomonas putida KT2440 for integration of a fluorescent protein expression construct. Insertion in five of the loci did not affect growth rate, but fluorescence varied by up to 27-fold. Three sites displaying a diversity of phenotypes with the fluorescent reporter were also chosen for the integration of a gene encoding a muconate importer. Depending on the integration locus, expression of the importer varied by approximately 3-fold and produced significant phenotypic differences. This work demonstrates the impact of the integration location on host viability, gene expression, and overall strain performance. Pseudomonas putida KT2440 chromosomal loci were characterized as potential insertion targets for heterologous genes. Integration location had a significant effect on heterologous protein expression and host phenotype. The identification of an appropriate chromosomal insertion location is essential to optimize genetic engineering design.
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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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Otto M, Wynands B, Drepper T, Jaeger KE, Thies S, Loeschcke A, Blank LM, Wierckx N. Targeting 16S rDNA for Stable Recombinant Gene Expression in Pseudomonas. ACS Synth Biol 2019; 8:1901-1912. [PMID: 31298831 DOI: 10.1021/acssynbio.9b00195] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Ribosomal RNA (rRNA) operons have recently been identified as promising sites for chromosomal integration of genetic elements in Pseudomonas putida, a bacterium that has gained considerable popularity as a microbial cell factory. We have developed a tool for targeted integration of recombinant genes into the rRNA operons of various Pseudomonas strains, where the native context of the rRNA clusters enables effective transcription of heterologous genes. However, a sufficient translation of foreign mRNA transcriptionally fused to rRNA required optimization of RNA secondary structures, which was achieved utilizing synthetic ribozymes and a bicistronic design. The generated tool further enabled the characterization of the six rRNA promoter units of P. putida S12 under different growth conditions. The presence of multiple, almost identical rRNA operons in Pseudomonas also allowed the integration of multiple copies of heterologous genetic elements. The integration of two expression cassettes and the resulting disruption of rRNA units only moderately affects growth rates, and the constructs were highly stable over more than 160 generations.
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Affiliation(s)
- Maike Otto
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Benedikt Wynands
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Karl-Erich Jaeger
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Stephan Thies
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Anita Loeschcke
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lars M. Blank
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nick Wierckx
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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Marine Biosurfactants: Biosynthesis, Structural Diversity and Biotechnological Applications. Mar Drugs 2019; 17:md17070408. [PMID: 31323998 PMCID: PMC6669457 DOI: 10.3390/md17070408] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 11/16/2022] Open
Abstract
Biosurfactants are amphiphilic secondary metabolites produced by microorganisms. Marine bacteria have recently emerged as a rich source for these natural products which exhibit surface-active properties, making them useful for diverse applications such as detergents, wetting and foaming agents, solubilisers, emulsifiers and dispersants. Although precise structural data are often lacking, the already available information deduced from biochemical analyses and genome sequences of marine microbes indicates a high structural diversity including a broad spectrum of fatty acid derivatives, lipoamino acids, lipopeptides and glycolipids. This review aims to summarise biosyntheses and structures with an emphasis on low molecular weight biosurfactants produced by marine microorganisms and describes various biotechnological applications with special emphasis on their role in the bioremediation of oil-contaminated environments. Furthermore, novel exploitation strategies are suggested in an attempt to extend the existing biosurfactant portfolio.
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