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Bertelmann C, Bühler B. Strategies found not to be suitable for stabilizing high steroid hydroxylation activities of CYP450 BM3-based whole-cell biocatalysts. PLoS One 2024; 19:e0309965. [PMID: 39240904 PMCID: PMC11379211 DOI: 10.1371/journal.pone.0309965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Accepted: 08/21/2024] [Indexed: 09/08/2024] Open
Abstract
The implementation of biocatalytic steroid hydroxylation processes plays a crucial role in the pharmaceutical industry due to a plethora of medicative effects of hydroxylated steroid derivatives and their crucial role in drug approval processes. Cytochrome P450 monooxygenases (CYP450s) typically constitute the key enzymes catalyzing these reactions, but commonly entail drawbacks such as poor catalytic rates and the dependency on additional redox proteins for electron transfer from NAD(P)H to the active site. Recently, these bottlenecks were overcome by equipping Escherichia coli cells with highly active variants of the self-sufficient single-component CYP450 BM3 together with hydrophobic outer membrane proteins facilitating cellular steroid uptake. The combination of the BM3 variant KSA14m and the outer membrane pore AlkL enabled exceptionally high testosterone hydroxylation rates of up to 45 U gCDW-1 for resting (i.e., living but non-growing) cells. However, a rapid loss of specific activity heavily compromised final product titers and overall space-time yields. In this study, several stabilization strategies were evaluated on enzyme-, cell-, and reaction level. However, neither changes in biocatalyst configuration nor variation of cultivation media, expression systems, or inducer concentrations led to considerable improvement. This qualified the so-far used genetic construct pETM11-ksa14m-alkL, M9 medium, and the resting-cell state as the best options enabling comparatively efficient activity along with fast growth prior to biotransformation. In summary, we report several approaches not enabling a stabilization of the high testosterone hydroxylation rates, providing vital guidance for researchers tackling similar CYP450 stability issues. A comparison with more stable natively steroid-hydroxylating CYP106A2 and CYP154C5 in equivalent setups further highlighted the high potential of the investigated CYP450 BM3-based whole-cell biocatalysts. The immense and continuously developing repertoire of enzyme engineering strategies provides promising options to stabilize the highly active biocatalysts.
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Affiliation(s)
- Carolin Bertelmann
- Department of Solar Materials Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Saxony, Germany
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Saxony, Germany
| | - Bruno Bühler
- Department of Solar Materials Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Saxony, Germany
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Saxony, Germany
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Nerke P, Korb J, Haala F, Hubmann G, Lütz S. Metabolic bottlenecks of Pseudomonas taiwanensis VLB120 during growth on d-xylose via the Weimberg pathway. Metab Eng Commun 2024; 18:e00241. [PMID: 39021639 PMCID: PMC11252243 DOI: 10.1016/j.mec.2024.e00241] [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: 04/02/2024] [Revised: 05/28/2024] [Accepted: 06/04/2024] [Indexed: 07/20/2024] Open
Abstract
The microbial production of value-added chemicals from renewable feedstocks is an important step towards a sustainable, bio-based economy. Therefore, microbes need to efficiently utilize lignocellulosic biomass and its dominant constituents, such as d-xylose. Pseudomonas taiwanensis VLB120 assimilates d-xylose via the five-step Weimberg pathway. However, the knowledge about the metabolic constraints of the Weimberg pathway, i.e., its regulation, dynamics, and metabolite fluxes, is limited, which hampers the optimization and implementation of this pathway for bioprocesses. We characterized the Weimberg pathway activity of P. taiwanensis VLB120 in terms of biomass growth and the dynamics of pathway intermediates. In batch cultivations, we found excessive accumulation of the intermediates d-xylonolactone and d-xylonate, indicating bottlenecks in d-xylonolactone hydrolysis and d-xylonate uptake. Moreover, the intermediate accumulation was highly dependent on the concentration of d-xylose and the extracellular pH. To encounter the apparent bottlenecks, we identified and overexpressed two genes coding for putative endogenous xylonolactonases PVLB_05820 and PVLB_12345. Compared to the control strain, the overexpression of PVLB_12345 resulted in an increased growth rate and biomass generation of up to 30 % and 100 %, respectively. Next, d-xylonate accumulation was decreased by overexpressing two newly identified d-xylonate transporter genes, PVLB_18545 and gntP (PVLB_13665). Finally, we combined xylonolactonase overexpression with enhanced uptake of d-xylonate by knocking out the gntP repressor gene gntR (PVLB_13655) and increased the growth rate and biomass yield by 50 % and 24 % in stirred-tank bioreactors, respectively. Our study contributes to the fundamental knowledge of the Weimberg pathway in pseudomonads and demonstrates how to encounter the metabolic bottlenecks of the Weimberg pathway to advance strain developments and cell factory design for bioprocesses on renewable feedstocks.
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Affiliation(s)
- Philipp Nerke
- Chair for Bioprocess Engineering, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Straße 66, 44227, Dortmund, Germany
| | - Jonas Korb
- Chair for Bioprocess Engineering, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Straße 66, 44227, Dortmund, Germany
| | - Frederick Haala
- Chair for Bioprocess Engineering, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Straße 66, 44227, Dortmund, Germany
| | - Georg Hubmann
- Chair for Bioprocess Engineering, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Straße 66, 44227, Dortmund, Germany
| | - Stephan Lütz
- Chair for Bioprocess Engineering, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Straße 66, 44227, Dortmund, Germany
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Lechtenberg T, Wynands B, Müller MF, Polen T, Noack S, Wierckx N. Improving 5-(hydroxymethyl)furfural (HMF) tolerance of Pseudomonas taiwanensis VLB120 by automated adaptive laboratory evolution (ALE). Metab Eng Commun 2024; 18:e00235. [PMID: 38832093 PMCID: PMC11144800 DOI: 10.1016/j.mec.2024.e00235] [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: 03/19/2024] [Revised: 04/29/2024] [Accepted: 05/07/2024] [Indexed: 06/05/2024] Open
Abstract
The aldehyde 5-(hydroxymethyl)furfural (HMF) is of great importance for a circular bioeconomy. It is a renewable platform chemical that can be converted into a range of useful compounds to replace petroleum-based products such as the green plastic monomer 2,5-furandicarboxylic acid (FDCA). However, it also exhibits microbial toxicity for example hindering the efficient biotechnological valorization of lignocellulosic hydrolysates. Thus, there is an urgent need for tolerance-improved organisms applicable to whole-cell biocatalysis. Here, we engineer an oxidation-deficient derivative of the naturally robust and emerging biotechnological workhorse P. taiwanensis VLB120 by robotics-assisted adaptive laboratory evolution (ALE). The deletion of HMF-oxidizing enzymes enabled for the first time evolution under constant selection pressure by the aldehyde, yielding strains with consistently improved growth characteristics in presence of the toxicant. Genome sequencing of evolved clones revealed loss-of function mutations in the LysR-type transcriptional regulator-encoding mexT preventing expression of the associated efflux pump mexEF-oprN. This knowledge allowed reverse engineering of strains with enhanced aldehyde tolerance, even in a background of active or overexpressed HMF oxidation machinery, demonstrating a synergistic effect of two distinct tolerance mechanisms.
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Affiliation(s)
- Thorsten Lechtenberg
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Benedikt Wynands
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Moritz-Fabian Müller
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Tino Polen
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Stephan Noack
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Nick Wierckx
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
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Neves D, Meinen D, Alter TB, Blank LM, Ebert BE. Expanding Pseudomonas taiwanensis VLB120's acyl-CoA portfolio: Propionate production in mineral salt medium. Microb Biotechnol 2024; 17:e14309. [PMID: 37537795 PMCID: PMC10832534 DOI: 10.1111/1751-7915.14309] [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: 02/13/2023] [Revised: 06/06/2023] [Accepted: 06/25/2023] [Indexed: 08/05/2023] Open
Abstract
As one of the main precursors, acetyl-CoA leads to the predominant production of even-chain products. From an industrial biotechnology perspective, extending the acyl-CoA portfolio of a cell factory is vital to producing industrial relevant odd-chain alcohols, acids, ketones and polyketides. The bioproduction of odd-chain molecules can be facilitated by incorporating propionyl-CoA into the metabolic network. The shortest pathway for propionyl-CoA production, which relies on succinyl-CoA catabolism encoded by the sleeping beauty mutase operon, was evaluated in Pseudomonas taiwanensis VLB120. A single genomic copy of the sleeping beauty mutase genes scpA, argK and scpB combined with the deletion of the methylcitrate synthase PVLB_08385 was sufficient to observe propionyl-CoA accumulation in this Pseudomonas. The chassis' capability for odd-chain product synthesis was assessed by expressing an acyl-CoA hydrolase, which enabled propionate synthesis. Three fed-batch strategies during bioreactor fermentations were benchmarked for propionate production, in which a maximal propionate titre of 2.8 g L-1 was achieved. Considering that the fermentations were carried out in mineral salt medium under aerobic conditions and that a single genome copy drove propionyl-CoA production, this result highlights the potential of Pseudomonas to produce propionyl-CoA derived, odd-chain products.
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Affiliation(s)
- Dário Neves
- Institute of Applied Microbiology‐iAMB, Aachen Biology and Biotechnology‐ABBtRWTH Aachen UniversityAachenGermany
| | - Daniel Meinen
- Institute of Applied Microbiology‐iAMB, Aachen Biology and Biotechnology‐ABBtRWTH Aachen UniversityAachenGermany
| | - Tobias B. Alter
- Institute of Applied Microbiology‐iAMB, Aachen Biology and Biotechnology‐ABBtRWTH Aachen UniversityAachenGermany
| | - Lars M. Blank
- Institute of Applied Microbiology‐iAMB, Aachen Biology and Biotechnology‐ABBtRWTH Aachen UniversityAachenGermany
| | - Birgitta E. Ebert
- Institute of Applied Microbiology‐iAMB, Aachen Biology and Biotechnology‐ABBtRWTH Aachen UniversityAachenGermany
- Australian Institute for Bioengineering and Nanotechnology (AIBN)The University of QueenslandBrisbaneQueenslandAustralia
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Froning M, Grütering C, Blank LM, Hayen H. Determination of double bond positions in methyl ketones by gas chromatography-mass spectrometry using dimethyl disulfide derivatives. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2023; 37:e9457. [PMID: 36512472 DOI: 10.1002/rcm.9457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/12/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
RATIONALE Methyl ketones are of interest for the application as biofuels. The fatty acid metabolism of different microbes has been rearranged to achieve a sustainable production of methyl ketones. The biofuel properties and possible further chemical modifications of these methyl ketones are influenced by their chain length, as well as their degree of saturation and the corresponding double bond position. METHODS A method based on gas chromatography-electron ionization; mass spectrometry (GC-EI-MS) was used to determine the double bond position of methyl ketones. Derivatization using dimethyl disulfide (DMDS) and an iodine catalyst enabled the activation of the double bonds for selective fragmentation during electron ionization. The cleavage led to key fragments in the Orbitrap high-resolution mass spectrum and allowed the unequivocal localization of the double bond position of the respective monounsaturated methyl ketone. RESULTS The double bond position of several medium chain length methyl ketones originating from the gram-negative bacterium Pseudomonas taiwanensis (P. taiwanensis) VLB120 was determined. The DMDS derivatives of methyl ketones can yield isobaric fragment ions for different possible double bond positions, which can be distinguished only using high-resolution MS. The double bond position of all methyl ketones deriving from P. taiwanensis VLB120 was the same, counting from the end of the aliphatic chain, and was determined as ω-7. CONCLUSIONS The derivatization of medium chain length monounsaturated methyl ketones with DMDS allowed the determination of the corresponding double bond position via GC-EI-MS. High-resolution MS is needed to differentiate possible double bond positions that yield isobaric fragment ions.
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Affiliation(s)
- Matti Froning
- Institute of Inorganic and Analytical Chemistry, University of Münster, Münster, Germany
| | - Carolin Grütering
- Institute of Applied Microbiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Lars M Blank
- Institute of Applied Microbiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Heiko Hayen
- Institute of Inorganic and Analytical Chemistry, University of Münster, Münster, Germany
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Abstract
Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a pathogen of global concern due to the fact that therapeutic drugs are limited. Metallo-β-lactamase (MBL)-producing P. aeruginosa has become a critical part of CRPA. Alcaligenes faecalis metallo-β-lactamase (AFM) is a newly identified subclass B1b MBL. In this study, 487 P. aeruginosa strains isolated from patients and the environment in an intensive care unit were screened for AFM alleles. Five AFM-producing strains were identified, including four AFM-2-producing strains (ST262) and one AFM-4-producing strain (ST671). AFM-2-producing strains were isolated from rectal and throat swabs, and AFM-4-producing strains were isolated from the water sink. The blaAFM-2 carrying plasmids belonged to the IncP-2 type, while the blaAFM-4 carrying plasmid pAR19438 was a pSTY-like megaplasmid. Plasmid pAR19438 was acquired blaAFM-4 by the integration of the Tn1403-like transposon. All blaAFM genes were embedded in an ISCR29-blaAFM unit core module flanked by class 1 integrons. The core module of blaAFM-2 was ISCR29-ΔgroL-blaAFM-2-bleMBL-ΔtrpF-ΔISCR, while the core module of blaAFM-4 was ISCR29-ΔgroL-blaAFM-2-bleMBL-ΔtrpF-ISCR-msrB-msrA-yfcG-corA-ΔISCR. The flanking sequences of ISCR29-blaAFM units also differed. The expression of AFM-2 and AFM-4 in DH5α and PAO1 illustrated the same effect for the evaluation of the MICs of β-lactams, except for aztreonam. Identification of AFM-4 underscores that the quick spread and emerging development of mutants of MBLs require continuous surveillance in P. aeruginosa. IMPORTANCE Acquiring metallo-β-lactamase genes is one of the important carbapenem resistance mechanisms of P. aeruginosa. Alcaligenes faecalis metallo-β-lactamase is a newly identified metallo-β-lactamase, the prevalence and genetic context of which need to be explored. In this study, we identified AFM-producing P. aeruginosa strains among clinical isolates and found a new mutant of AFM, AFM-4. The blaAFM-4 carrying plasmid pAR19438 was a pSTY-like megaplasmid, unlike the plasmids encoding other blaAFM alleles. The genetic context of blaAFM-4 was also different. However, AFM-2 and AFM-4 had the same impacts on antibiotic susceptibility. The presence and transmission of AFM alleles in P. aeruginosa pose a challenge to clinical practice.
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Kusumawardhani H, Hosseini R, Verschoor JA, de Winde JH. Comparative analysis reveals the modular functional structure of conjugative megaplasmid pTTS12 of Pseudomonas putida S12: A paradigm for transferable traits, plasmid stability, and inheritance? Front Microbiol 2022; 13:1001472. [PMID: 36212887 PMCID: PMC9537497 DOI: 10.3389/fmicb.2022.1001472] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 09/06/2022] [Indexed: 11/26/2022] Open
Abstract
Originating from various environmental niches, large numbers of bacterial plasmids have been found carrying heavy metal and antibiotic resistance genes, degradation pathways and specific transporter genes for organic solvents or aromatic compounds. Such genes may constitute promising candidates for novel synthetic biology applications. Our systematic analysis of gene clusters encoded on megaplasmid pTTS12 from Pseudomonas putida S12 underscores that a large portion of its genes is involved in stress response to increase survival under harsh conditions like the presence of heavy metal and organic solvent. We investigated putative roles of genes encoded on pTTS12 and further elaborated on their roles in the establishment and maintenance under several stress conditions, specifically focusing on solvent tolerance in P. putida strains. The backbone of pTTS12 was found to be closely related to that of the carbapenem-resistance plasmid pOZ176, member of the IncP-2 incompatibility group, although the carbapenem resistance cassette is absent from pTTS12. Megaplasmid pTTS12 contains multiple transposon-flanked cassettes mediating resistance to various heavy metals such as tellurite, chromate (Tn7), and mercury (Tn5053 and Tn5563). Additionally, pTTS12 also contains a P-type, Type IV secretion system (T4SS) supporting self-transfer to other P. putida strains. This study increases our understanding in the modular structure of pTTS12 as a member of IncP-2 plasmid family and several promising exchangeable gene clusters to construct robust microbial hosts for biotechnology applications.
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Affiliation(s)
- Hadiastri Kusumawardhani
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Rohola Hosseini
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | | | - Johannes H. de Winde
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
- *Correspondence: Johannes H. de Winde,
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Lopez-Lopez K, Lozano Mahecha RA. Aislamiento y caracterización de bacterias endémicas colombianas con capacidad de degradar tolueno. REVISTA COLOMBIANA DE BIOTECNOLOGÍA 2022. [DOI: 10.15446/rev.colomb.biote.v24n1.98613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Los hidrocarburos aromáticos monocíclicos: benceno, tolueno, etilbenceno y xileno (BTEX), presentes en crudo y refinados de petróleo, hacen parte de los compuestos con más impacto en el medio ambiente y la salud humana, debido a su naturaleza cancerígena, mutagénica y altamente tóxica. Esta investigación tuvo como objetivo obtener y caracterizar bacterias capaces de degradar tolueno. Se realizaron tres muestreos de suelo contaminado con hidrocarburos del Valle del Cauca en tres condiciones: gasolinería, derrame accidental y taller mecánico. Se aislaron bacterias capaces de crecer en tolueno vapor como única fuente de carbono y se caracterizaron a nivel morfológico, bioquímico y molecular. Para la caracterización molecular se amplificó, secuenció y analizó con herramientas bioinformáticas el gen ribosomal 16S. Se evaluó la utilización de tolueno directo con concentración al 1% como única fuente de carbono. Se logró aislar 29 bacterias con capacidad de metabolizar tolueno. La caracterización bioquímica y molecular identificó a las bacterias aisladas de suelo contaminado como Pseudomonas y Stenotrophomonas. Las bacterias aisladas en el taller mecánico resultaron ser los microorganismos con mejor crecimiento en tolueno como fuente de carbono, poseen un gran potencial para ser utilizadas para fines de biorremediación de suelos y aguas contaminadas con BTEX.
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Chen F, Wang P, Yin Z, Yang H, Hu L, Yu T, Jing Y, Guan J, Wu J, Zhou D. VIM-encoding Inc pSTY plasmids and chromosome-borne integrative and mobilizable elements (IMEs) and integrative and conjugative elements (ICEs) in Pseudomonas. Ann Clin Microbiol Antimicrob 2022; 21:10. [PMID: 35264204 PMCID: PMC8905914 DOI: 10.1186/s12941-022-00502-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 03/02/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The carbapenem-resistance genes blaVIM are widely disseminated in Pseudomonas, and frequently harbored within class 1 integrons that reside within various mobile genetic elements (MGEs). However, there are few reports on detailed genetic dissection of blaVIM-carrying MGEs in Pseudomonas. METHODS This study presented the complete sequences of five blaVIM-2/-4-carrying MGEs, including two plasmids, two chromosomal integrative and mobilizable elements (IMEs), and one chromosomal integrative and conjugative element (ICE) from five different Pseudomonas isolates. RESULTS The two plasmids were assigned to a novel incompatibility (Inc) group IncpSTY, which included only seven available plasmids with determined complete sequences and could be further divided into three subgroups IncpSTY-1/2/3. A detailed sequence comparison was then applied to a collection of 15 MGEs belonging to four different groups: three representative IncpSTY plasmids, two Tn6916-related IMEs, two Tn6918-related IMEs, and eight Tn6417-related ICEs and ten of these 15 MGEs were first time identified. At least 22 genes involving resistance to seven different categories of antibiotics and heavy metals were identified within these 15 MGEs, and most of these resistance genes were located within the accessory modules integrated as exogenous DNA regions into these MGEs. Especially, eleven of these 15 MGEs carried the blaVIM genes, which were located within 11 different concise class 1 integrons. CONCLUSION These blaVIM-carrying integrons were further integrated into the above plasmids, IMEs/ICEs with intercellular mobility. These MGEs could transfer between Pseudomonas isolates, which resulted in the accumulation and spread of blaVIM among Pseudomonas and thus was helpful for the bacteria to survival from the stress of antibiotics. Data presented here provided a deeper insight into the genetic diversification and evolution of VIM-encoding MGEs in Pseudomonas.
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Affiliation(s)
- Fangzhou Chen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.,Basic Medical College, Guizhou Medical University, Guiyang, 550025, China.,Guangzhou Medical University, Guangzhou, 511436, China
| | - Peng Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Zhe Yin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Huiying Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Lingfei Hu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Ting Yu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Ying Jing
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Jiayao Guan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Jiahong Wu
- Basic Medical College, Guizhou Medical University, Guiyang, 550025, China.
| | - Dongsheng Zhou
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China. .,Guangzhou Medical University, Guangzhou, 511436, China.
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Phale PS, Mohapatra B, Malhotra H, Shah BA. Eco-physiological portrait of a novel Pseudomonas sp. CSV86: an ideal host/candidate for metabolic engineering and bioremediation. Environ Microbiol 2021; 24:2797-2816. [PMID: 34347343 DOI: 10.1111/1462-2920.15694] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 11/30/2022]
Abstract
Pseudomonas sp. CSV86, an Indian soil isolate, degrades wide range of aromatic compounds like naphthalene, benzoate and phenylpropanoids, amongst others. Isolate displays the unique and novel property of preferential utilization of aromatics over glucose and co-metabolizes them with organic acids. Interestingly, as compared to other Pseudomonads, strain CSV86 harbours only high-affinity glucokinase pathway (and absence of low-affinity oxidative route) for glucose metabolism. Such lack of gluconate loop might be responsible for the novel phenotype of preferential utilization of aromatics. The genome analysis and comparative functional mining indicated a large genome (6.79 Mb) with significant enrichment of regulators, transporters as well as presence of various secondary metabolite production clusters, suggesting its eco-physiological and metabolic versatility. Strain harbours various integrative conjugative elements (ICEs) and genomic islands, probably acquired through horizontal gene transfer events, leading to genome mosaicity and plasticity. Naphthalene degradation genes are arranged as regulonic clusters and found to be part of ICECSV86nah . Various eco-physiological properties and absence of major pathogenicity and virulence factors (risk group-1) in CSV86 suggest it to be an ideal candidate for bioremediation. Further, strain can serve as an ideal chassis for metabolic engineering to degrade various xenobiotics preferentially over simple carbon sources for efficient remediation.
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Affiliation(s)
- Prashant S Phale
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai, Maharashtra, 400076, India
| | - Balaram Mohapatra
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai, Maharashtra, 400076, India
| | - Harshit Malhotra
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai, Maharashtra, 400076, India
| | - Bhavik A Shah
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai, Maharashtra, 400076, India
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Bretschneider L, Heuschkel I, Ahmed A, Bühler K, Karande R, Bühler B. Characterization of different biocatalyst formats for BVMO-catalyzed cyclohexanone oxidation. Biotechnol Bioeng 2021; 118:2719-2733. [PMID: 33844297 DOI: 10.1002/bit.27791] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/03/2021] [Accepted: 04/04/2021] [Indexed: 01/05/2023]
Abstract
Cyclohexanone monooxygenase (CHMO), a member of the Baeyer-Villiger monooxygenase family, is a versatile biocatalyst that efficiently catalyzes the conversion of cyclic ketones to lactones. In this study, an Acidovorax-derived CHMO gene was expressed in Pseudomonas taiwanensis VLB120. Upon purification, the enzyme was characterized in vitro and shown to feature a broad substrate spectrum and up to 100% conversion in 6 h. Furthermore, we determined and compared the cyclohexanone conversion kinetics for different CHMO-biocatalyst formats, that is, isolated enzyme, suspended whole cells, and biofilms, the latter two based on recombinant CHMO-containing P. taiwanensis VLB120. Biofilms showed less favorable values for KS (9.3-fold higher) and kcat (4.8-fold lower) compared with corresponding KM and kcat values of isolated CHMO, but a favorable KI for cyclohexanone (5.3-fold higher). The unfavorable KS and kcat values are related to mass transfer- and possibly heterogeneity issues and deserve further investigation and engineering, to exploit the high potential of biofilms regarding process stability. Suspended cells showed only 1.8-fold higher KS , but 1.3- and 4.2-fold higher kcat and KI values than isolated CHMO. This together with the efficient NADPH regeneration via glucose metabolism makes this format highly promising from a kinetics perspective.
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Affiliation(s)
- Lisa Bretschneider
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Ingeborg Heuschkel
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Afaq Ahmed
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Katja Bühler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Rohan Karande
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
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12
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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: 103] [Impact Index Per Article: 25.8] [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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13
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Nies SC, Alter TB, Nölting S, Thiery S, Phan ANT, Drummen N, Keasling JD, Blank LM, Ebert BE. High titer methyl ketone production with tailored Pseudomonas taiwanensis VLB120. Metab Eng 2020; 62:84-94. [PMID: 32810591 DOI: 10.1016/j.ymben.2020.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/13/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Methyl ketones present a group of highly reduced platform chemicals industrially produced from petroleum-derived hydrocarbons. They find applications in the fragrance, flavor, pharmacological, and agrochemical industries, and are further discussed as biodiesel blends. In recent years, intense research has been carried out to achieve sustainable production of these molecules by re-arranging the fatty acid metabolism of various microbes. One challenge in the development of a highly productive microbe is the high demand for reducing power. Here, we engineered Pseudomonas taiwanensis VLB120 for methyl ketone production as this microbe has been shown to sustain exceptionally high NAD(P)H regeneration rates. The implementation of published strategies resulted in 2.1 g Laq-1 methyl ketones in fed-batch fermentation. We further increased the production by eliminating competing reactions suggested by metabolic analyses. These efforts resulted in the production of 9.8 g Laq-1 methyl ketones (corresponding to 69.3 g Lorg-1 in the in situ extraction phase) at 53% of the maximum theoretical yield. This represents a 4-fold improvement in product titer compared to the initial production strain and the highest titer of recombinantly produced methyl ketones reported to date. Accordingly, this study underlines the high potential of P. taiwanensis VLB120 to produce methyl ketones and emphasizes model-driven metabolic engineering to rationalize and accelerate strain optimization efforts.
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Affiliation(s)
- Salome C Nies
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Tobias B Alter
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Sophia Nölting
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Susanne Thiery
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - An N T Phan
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Noud Drummen
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Jay D Keasling
- Joint BioEnergy Institute, Emeryville, CA, 94608, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Lyngby, Denmark; Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, 94720, USA; Virtual Institute of Microbial Stress and Survival, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA; Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA; Dept. of Bioengineering, University of California, Berkeley, CA, 94720, USA; Dept. of Chemical Engineering, University of California, Berkeley, CA, 94720, USA; Synthetic Biochemistry Center, Institute for Synthetic Biology, Shenzhen Institutes for Advanced Technologies, Shenzhen, China
| | - Lars M Blank
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany
| | - Birgitta E Ebert
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, DE, Germany; Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD, 4072, Australia; CSIRO Future Science Platform in Synthetic Biology, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Black Mountain, ACT, 2601, Australia.
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14
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A Combined Bio-Chemical Synthesis Route for 1-Octene Sheds Light on Rhamnolipid Structure. Catalysts 2020. [DOI: 10.3390/catal10080874] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Here we report a chemoenzymatic approach to synthesize 1-octene from carbohydrates via ethenolysis of rhamnolipids. Rhamnolipids synthesized by P. putida contain a double bond between carbon five and six, which is experimentally confirmed via olefin cross metathesis. Utilizing these lipids in the ethenolysis catalyzed by a Grubbs−Hoveyda-type catalyst selectively generates 1-octene and with good conversions. This study shows the potential of chemoenzymatic approaches to produce compounds for the chemical industry from renewable resources.
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15
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Common problems associated with the microbial productions of aromatic compounds and corresponding metabolic engineering strategies. Biotechnol Adv 2020; 41:107548. [DOI: 10.1016/j.biotechadv.2020.107548] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 04/06/2020] [Accepted: 04/08/2020] [Indexed: 01/06/2023]
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16
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Biodiversity of Microorganisms Colonizing the Surface of Polystyrene Samples Exposed to Different Aqueous Environments. SUSTAINABILITY 2020. [DOI: 10.3390/su12093624] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The contamination of marine and freshwater ecosystems with the items from thermoplastics, including polystyrene (PS), necessitates the search for efficient microbial degraders of these polymers. In the present study, the composition of prokaryotes in biofilms formed on PS samples incubated in seawater and the industrial water of a petrochemical plant were investigated. Using a high-throughput sequencing of the V3–V4 region of the 16S rRNA gene, the predominance of Alphaproteobacteria (Blastomonas), Bacteroidetes (Chryseolinea), and Gammaproteobacteria (Arenimonas and Pseudomonas) in the biofilms on PS samples exposed to industrial water was revealed. Alphaproteobacteria (Erythrobacter) predominated on seawater-incubated PS samples. The local degradation of the PS samples was confirmed by scanning microscopy. The PS-colonizing microbial communities in industrial water differed significantly from the PS communities in seawater. Both communities have a high potential ability to carry out the carbohydrates and amino acids metabolism, but the potential for xenobiotic degradation, including styrene degradation, was relatively higher in the biofilms in industrial water. Bacteria of the genera Erythrobacter, Maribacter, and Mycobacterium were potential styrene-degraders in seawater, and Pseudomonas and Arenimonas in industrial water. Our results suggest that marine and industrial waters contain microbial populations potentially capable of degrading PS, and these populations may be used for the isolation of efficient PS degraders.
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17
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Nitschel R, Ankenbauer A, Welsch I, Wirth NT, Massner C, Ahmad N, McColm S, Borges F, Fotheringham I, Takors R, Blombach B. Engineering Pseudomonas putida KT2440 for the production of isobutanol. Eng Life Sci 2020; 20:148-159. [PMID: 32874178 PMCID: PMC7447888 DOI: 10.1002/elsc.201900151] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/08/2019] [Accepted: 12/10/2019] [Indexed: 11/06/2022] Open
Abstract
We engineered P. putida for the production of isobutanol from glucose by preventing product and precursor degradation, inactivation of the soluble transhydrogenase SthA, overexpression of the native ilvC and ilvD genes, and implementation of the feedback-resistant acetolactate synthase AlsS from Bacillus subtilis, ketoacid decarboxylase KivD from Lactococcus lactis, and aldehyde dehydrogenase YqhD from Escherichia coli. The resulting strain P. putida Iso2 produced isobutanol with a substrate specific product yield (Y Iso/S) of 22 ± 2 mg per gram of glucose under aerobic conditions. Furthermore, we identified the ketoacid decarboxylase from Carnobacterium maltaromaticum to be a suitable alternative for isobutanol production, since replacement of kivD from L. lactis in P. putida Iso2 by the variant from C. maltaromaticum yielded an identical YIso/S. Although P. putida is regarded as obligate aerobic, we show that under oxygen deprivation conditions this bacterium does not grow, remains metabolically active, and that engineered producer strains secreted isobutanol also under the non-growing conditions.
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Affiliation(s)
- Robert Nitschel
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Andreas Ankenbauer
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Ilona Welsch
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Nicolas T. Wirth
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Christoph Massner
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Naveed Ahmad
- Ingenza Ltd., Roslin Innovation CentreCharnock Bradley Building, Easter Bush CampusRoslinUK
| | - Stephen McColm
- Ingenza Ltd., Roslin Innovation CentreCharnock Bradley Building, Easter Bush CampusRoslinUK
| | - Frédéric Borges
- Laboratoire d'Ingénierie des Biomolécules (LIBio)Université de LorraineNancyFrance
| | - Ian Fotheringham
- Ingenza Ltd., Roslin Innovation CentreCharnock Bradley Building, Easter Bush CampusRoslinUK
| | - Ralf Takors
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
| | - Bastian Blombach
- Institute of Biochemical EngineeringUniversity of StuttgartStuttgartGermany
- Microbial Biotechnology, Campus Straubing for Biotechnology and SustainabilityTechnical University of MunichStraubingGermany
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18
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Schäfer L, Karande R, Bühler B. Maximizing Biocatalytic Cyclohexane Hydroxylation by Modulating Cytochrome P450 Monooxygenase Expression in P. taiwanensis VLB120. Front Bioeng Biotechnol 2020; 8:140. [PMID: 32175317 PMCID: PMC7056670 DOI: 10.3389/fbioe.2020.00140] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/11/2020] [Indexed: 01/31/2023] Open
Abstract
Cytochrome P450 monooxygenases (Cyps) effectively catalyze the regiospecific oxyfunctionalization of inert C-H bonds under mild conditions. Due to their cofactor dependency and instability in isolated form, oxygenases are preferably applied in living microbial cells with Pseudomonas strains constituting potent host organisms for Cyps. This study presents a holistic genetic engineering approach, considering gene dosage, transcriptional, and translational levels, to engineer an effective Cyp-based whole-cell biocatalyst, building on recombinant Pseudomonas taiwanensis VLB120 for cyclohexane hydroxylation. A lac-based regulation system turned out to be favorable in terms of orthogonality to the host regulatory network and enabled a remarkable specific whole-cell activity of 34 U gCDW -1. The evaluation of different ribosomal binding sites (RBSs) revealed that a moderate translation rate was favorable in terms of the specific activity. An increase in gene dosage did only slightly elevate the hydroxylation activity, but severely impaired growth and resulted in a large fraction of inactive Cyp. Finally, the introduction of a terminator reduced leakiness. The optimized strain P. taiwanensis VLB120 pSEVA_Cyp allowed for a hydroxylation activity of 55 U gCDW -1. Applying 5 mM cyclohexane, molar conversion and biomass-specific yields of 82.5% and 2.46 mmolcyclohexanol gbiomass -1 were achieved, respectively. The strain now serves as a platform to design in vivo cascades and bioprocesses for the production of polymer building blocks such as ε-caprolactone.
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Affiliation(s)
- Lisa Schäfer
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
| | - Rohan Karande
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
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19
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Neves D, Vos S, Blank LM, Ebert BE. Pseudomonas mRNA 2.0: Boosting Gene Expression Through Enhanced mRNA Stability and Translational Efficiency. Front Bioeng Biotechnol 2020; 7:458. [PMID: 32039175 PMCID: PMC6993053 DOI: 10.3389/fbioe.2019.00458] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 12/19/2019] [Indexed: 11/14/2022] Open
Abstract
High gene expression of enzymes partaking in recombinant production pathways is a desirable trait among cell factories belonging to all different kingdoms of life. High enzyme abundance is generally aimed for by utilizing strong promoters, which ramp up gene transcription and mRNA levels. Increased protein abundance can alternatively be achieved by optimizing the expression on the post-transcriptional level. Here, we evaluated protein synthesis with a previously proposed optimized gene expression architecture, in which mRNA stability and translation initiation are modulated by genetic parts such as self-cleaving ribozymes and a bicistronic design, which have initially been described to support the standardization of gene expression. The optimized gene expression architecture was tested in Pseudomonas taiwanensis VLB120, a promising, novel microbial cell factory. The expression cassette was employed on a plasmid basis and after single genomic integration. We used three constitutive and two inducible promoters to drive the expression of two fluorescent reporter proteins and a short acetoin biosynthesis pathway. The performance was confronted with that of a traditional expression cassette harboring the same promoter and gene of interest but lacking the genetic parts for increased expression efficiency. The optimized expression cassette granted higher protein abundance independently of the expression basis or promoter used proving its value for applications requiring high protein abundance.
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Affiliation(s)
- Dário Neves
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany
| | - Stefan Vos
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany
| | - Lars M Blank
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany
| | - Birgitta E Ebert
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany.,Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia.,CSIRO Synthetic Biology Future Science Platform, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Brisbane, QLD, Australia
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20
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Otto M, Wynands B, Lenzen C, Filbig M, Blank LM, Wierckx N. Rational Engineering of Phenylalanine Accumulation in Pseudomonas taiwanensis to Enable High-Yield Production of Trans-Cinnamate. Front Bioeng Biotechnol 2019; 7:312. [PMID: 31824929 PMCID: PMC6882275 DOI: 10.3389/fbioe.2019.00312] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 10/23/2019] [Indexed: 12/31/2022] Open
Abstract
Microbial biocatalysis represents a promising alternative for the production of a variety of aromatic chemicals, where microorganisms are engineered to convert a renewable feedstock under mild production conditions into a valuable chemical building block. This study describes the rational engineering of the solvent-tolerant bacterium Pseudomonas taiwanensis VLB120 toward accumulation of L-phenylalanine and its conversion into the chemical building block t-cinnamate. We recently reported rational engineering of Pseudomonas toward L-tyrosine accumulation by the insertion of genetic modifications that allow both enhanced flux and prevent aromatics degradation. Building on this knowledge, three genes encoding for enzymes involved in the degradation of L-phenylalanine were deleted to allow accumulation of 2.6 mM of L-phenylalanine from 20 mM glucose. The amino acid was subsequently converted into the aromatic model compound t-cinnamate by the expression of a phenylalanine ammonia-lyase (PAL) from Arabidopsis thaliana. The engineered strains produced t-cinnamate with yields of 23 and 39% Cmol Cmol−1 from glucose and glycerol, respectively. Yields were improved up to 48% Cmol Cmol−1 from glycerol when two enzymes involved in the shikimate pathway were additionally overexpressed, however with negative impact on strain performance and reproducibility. Production titers were increased in fed-batch fermentations, in which 33.5 mM t-cinnamate were produced solely from glycerol, in a mineral medium without additional complex supplements. The aspect of product toxicity was targeted by the utilization of a streamlined, genome-reduced strain, which improves upon the already high tolerance of P. taiwanensis VLB120 toward t-cinnamate.
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Affiliation(s)
- Maike Otto
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Benedikt Wynands
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Christoph Lenzen
- Institute of Applied Microbiology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Melanie Filbig
- Institute of Applied Microbiology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Lars M Blank
- Institute of Applied Microbiology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Nick Wierckx
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, Jülich, Germany
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21
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Wynands B, Otto M, Runge N, Preckel S, Polen T, Blank LM, Wierckx N. Streamlined Pseudomonas taiwanensis VLB120 Chassis Strains with Improved Bioprocess Features. ACS Synth Biol 2019; 8:2036-2050. [PMID: 31465206 DOI: 10.1021/acssynbio.9b00108] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Microbes harbor many traits that are dispensable or even unfavorable under industrial and laboratory settings. The elimination of such traits could improve the host's efficiency, genetic stability, and robustness, thereby increasing the predictability and boosting its performance as a microbial cell factory. We engineered solvent-tolerant Pseudomonas taiwanensis VLB120 to yield streamlined chassis strains with higher growth rates and biomass yields, enhanced solvent tolerance, and improved process performance. In total, the genome was reduced by up to 10%. This was achieved by the elimination of genes that enable the cell to swim and form biofilms and by the deletion of the megaplasmid pSTY and large proviral segments. The resulting strain GRC1 had a 15% higher growth rate and biomass yield than the wildtype. However, this strain lacks the pSTY-encoded efflux pump TtgGHI, rendering it solvent-sensitive. Through reintegration of ttgGHI by chromosomal insertion without (GRC2) and with (GRC3) the corresponding regulator genes, the solvent-tolerant phenotype was enhanced. The generated P. taiwanensis GRC strains enlarge the repertoire of streamlined chassis with enhanced key performance indicators, making them attractive hosts for biotechnological applications. The different solvent tolerance levels of GRC1, GRC2, and GRC3 enable the selection of a fitting host platform in relation to the desired process requirements in a chassis à la carte principle. This was demonstrated in a metabolic engineering approach for the production of phenol from glycerol. The streamlined producer GRC1Δ5-TPL38 outperformed the equivalent nonstreamlined producer VLB120Δ5-TPL38 concerning phenol titer, rate, and yield, thereby highlighting the added value of the streamlined chassis.
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Affiliation(s)
- Benedikt Wynands
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Maike Otto
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nadine Runge
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Sarah Preckel
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Tino Polen
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lars M. Blank
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Nick Wierckx
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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22
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Volmer J, Lindmeyer M, Seipp J, Schmid A, Bühler B. Constitutively solvent‐tolerantPseudomonas taiwanensisVLB120∆C∆ttgVsupports particularly high‐styrene epoxidation activities when grown under glucose excess conditions. Biotechnol Bioeng 2019; 116:1089-1101. [DOI: 10.1002/bit.26924] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/17/2018] [Accepted: 01/06/2019] [Indexed: 01/08/2023]
Affiliation(s)
- Jan Volmer
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
| | - Martin Lindmeyer
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
| | - Julia Seipp
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
| | - Andreas Schmid
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
| | - Bruno Bühler
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
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23
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Scholz K, Tiso T, Blank LM, Hayen H. Mass spectrometric characterization of siderophores produced by Pseudomonas taiwanensis VLB120 assisted by stable isotope labeling of nitrogen source. Biometals 2018; 31:785-795. [PMID: 29956040 DOI: 10.1007/s10534-018-0122-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 06/17/2018] [Indexed: 12/17/2022]
Abstract
The structures of three previously unknown siderophores produced by the fluorescent, biotechnologically relevant Pseudomonas taiwanensis (P. taiwanensis) VLB120 bacteria were elucidated by means of hydrophilic interaction liquid chromatography (HILIC) hyphenated to high-resolution tandem mass spectrometry (HRMS/MS). They could be verified as iron(III)- and aluminum(III) complexes as well as the protonated molecules of the siderophores formed by in-source fragmentation. The siderophores were separated according to their different acyl side chains and additionally according their central ions. One of the siderophores was identified as pyoverdine with a malic acid (hydroxy succinic acid) amide side chain and a peptide moiety consisting of Orn-Asp-OHAsn-Thr-AcOHOrn-Ser-cOHOrn. The other analytes were assigned to an azotobactin with the identical peptide chain linked to the characteristic chromophoric unit and a pyoverdine with a variation in the amino acid sequence. Proline is directly linked to the pyoverdine chromophore instead of ornithine. Acidic and enzymatic hydrolyses were carried out to analyze the individual amino acids. Beside OHAsn, each amino acid of the peptide part was identified by HILIC-HRMS and comparison to authentic standards. Additionally, 15N-labeled cellular supernatants were analyzed by means of HRMS/MS. The results of the MS/MS experiments complemented by accurate mass data facilitated elucidation of the structures studied in this work and provided further confirmation of the three recently described pyoverdines of P. taiwanensis VLB120 (Baune et al. in Biometals 30:589-597, 2017. https://doi.org/10.1007/s10534-017-0029-7 ).
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Affiliation(s)
- Karen Scholz
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstraße 30, 48149, Münster, Germany
| | - Till Tiso
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Lars M Blank
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Heiko Hayen
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstraße 30, 48149, Münster, Germany.
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24
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Wynands B, Lenzen C, Otto M, Koch F, Blank LM, Wierckx N. Metabolic engineering of Pseudomonas taiwanensis VLB120 with minimal genomic modifications for high-yield phenol production. Metab Eng 2018; 47:121-133. [PMID: 29548982 DOI: 10.1016/j.ymben.2018.03.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 03/07/2018] [Accepted: 03/11/2018] [Indexed: 12/31/2022]
Abstract
Aromatic chemicals are important building blocks for the production of a multitude of everyday commodities. Currently, aromatics production relies almost exclusively on petrochemical processes. To achieve sustainability, alternative synthesis methods need to be developed. Here, we strived for an efficient production of phenol, a model aromatic compound of industrial relevance, from renewable carbon sources using the solvent-tolerant biocatalyst Pseudomonas taiwanensis VLB120. First, multiple catabolic routes for the degradation of aromatics and related compounds were inactivated, thereby obtaining the chassis strain P. taiwanensis VLB120Δ5 incapable of growing on 4-hydroxybenzoate (ΔpobA), tyrosine (Δhpd), and quinate (ΔquiC, ΔquiC1, ΔquiC2). In this context, a novel gene contributing to the quinate catabolism was identified (quiC2). Second, we employed a combination of reverse- and forward engineering to increase metabolic flux towards the product, using leads obtained from the analysis of aromatics producing Pseudomonas putida strains previously generated by mutagenesis. Phenol production was enabled by the heterologous expression of a codon-optimized and chromosomally integrated tyrosine phenol-lyase encoding gene from Pantoea agglomerans AJ2985 (PaTPL2). The genomic modification of endogenous genes encoding TrpEP290S, AroF-1P148L, and PheAT310I, and the deletion of pykA improved phenol production 17-fold, while also minimizing the burden caused by plasmids and auxotrophies. The additional overexpression of known bottleneck enzymes (AroGfbr, TyrAfbr) derived from Escherichia coli further enhanced phenol titers. The best producing strain P. taiwanensis VLB120Δ5-TPL36 reached yields of 15.8% and 18.5% (Cmol/Cmol) phenol from glucose and glycerol, respectively, in a mineral medium without addition of complex nutrients. This is the highest yield ever reported for microbially produced phenol.
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Affiliation(s)
- Benedikt Wynands
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Christoph Lenzen
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Maike Otto
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Falk Koch
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Lars M Blank
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Nick Wierckx
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany.
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Wordofa GG, Kristensen M. Tolerance and metabolic response of Pseudomonas taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:199. [PMID: 30034525 PMCID: PMC6052574 DOI: 10.1186/s13068-018-1192-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 07/06/2018] [Indexed: 05/10/2023]
Abstract
BACKGROUND Bio-conversion of lignocellulosic biomass to high-value products offers numerous benefits; however, its development is hampered by chemical inhibitors generated during the pretreatment process. A better understanding of how microbes naturally respond to those inhibitors is valuable in the process of designing microorganisms with improved tolerance. Pseudomonas taiwanensis VLB120 is a natively tolerant strain that utilizes a wide range of carbon sources including pentose and hexose sugars. To this end, we investigated the tolerance and metabolic response of P. taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors including organic acids (acetic acid, formic acid, and levulinic acid), furans (furfural, 5-hydroxymethylfurfural), and phenols (vanillin). RESULTS The inhibitory effect of the tested compounds varied with respect to lag phase, specific growth rate, and biomass yield compared to the control cultures grown under the same conditions without addition of inhibitors. However, P. taiwanensis was able to oxidize vanillin and furfural to vanillic acid and 2-furoic acid, respectively. Vanillic acid was further metabolized, whereas 2-furoic acid was secreted outside the cells and remained in the fermentation broth without further conversion. Acetic acid and formic acid were completely consumed from the fermentation broth, while concentration of levulinic acid remained constant throughout the fermentation process. Analysis of free intracellular metabolites revealed varying levels when P. taiwanensis VLB120 was exposed to inhibitory compounds. This resulted in increased levels of ATP to export inhibitors from the cell and NADPH/NADP ratio that provides reducing power to deal with the oxidative stress caused by the inhibitors. Thus, adequate supply of these metabolites is essential for the survival and reproduction of P. taiwanensis in the presence of biomass-derived inhibitors. CONCLUSIONS In this study, the tolerance and metabolic response of P. taiwanensis VLB120 to biomass hydrolysate-derived inhibitors was investigated. P. taiwanensis VLB120 showed high tolerance towards biomass hydrolysate-derived inhibitors compared to most wild-type microbes reported in the literature. It adopts different resistance mechanisms, including detoxification, efflux, and repair, which require additional energy and resources. Thus, targeting redox and energy metabolism in strain engineering may be a successful strategy to overcome inhibition during biomass hydrolysate conversion and lead to development of more robust strains.
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Affiliation(s)
- Gossa G. Wordofa
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Mette Kristensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
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Multiple Roles for Two Efflux Pumps in the Polycyclic Aromatic Hydrocarbon-Degrading Pseudomonas putida Strain B6-2 (DSM 28064). Appl Environ Microbiol 2017; 83:AEM.01882-17. [PMID: 29030440 DOI: 10.1128/aem.01882-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 10/02/2017] [Indexed: 11/20/2022] Open
Abstract
Microbial bioremediation is a promising approach for the removal of polycyclic aromatic hydrocarbon (PAH) contaminants. Many degraders of PAHs possess efflux pump genes in their genomes; however, their specific roles in the degradation of PAHs have not been clearly elucidated. In this study, two efflux pumps, TtgABC and SrpABC, were systematically investigated to determine their functions in a PAH-degrading Pseudomonas putida strain B6-2 (DSM 28064). The disruption of genes ttgABC or srpABC resulted in a defect in organic solvent tolerance. TtgABC was found to contribute to antibiotic resistance; SrpABC only contributed to antibiotic resistance under an artificial overproduced condition. Moreover, a mutant strain without srpABC did not maintain its activity in long-term biphenyl (BP) degradation, which correlated with the loss of cell viability. The expression of SrpABC was significantly upregulated in the course of BP degradation. BP, 2-hydroxybiphenyl, 3-hydroxybiphenyl, and 2,3-dihydroxybiphenyl (2,3-DHBP) were revealed to be the inducers of srpABC 2,3-DHBP was verified to be a substrate of pump SrpABC; SrpABC can enhance the tolerance to 2,3-DHBP by pumping it out. The mutant strain B6-2ΔsrpS prolonged BP degradation with the increase of srpABC expression. These results suggest that the pump SrpABC of strain B6-2 plays a positive role in BP biodegradation by pumping out metabolized toxic substances such as 2,3-DHBP. This study provides insights into the versatile physiological functions of the widely distributed efflux pumps in the biodegradation of PAHs.IMPORTANCE Polycyclic aromatic hydrocarbons (PAHs) are notorious for their recalcitrance to degradation in the environment. A high frequency of the occurrence of the efflux pump genes was observed in the genomes of effective PAH degraders; however, their specific roles in the degradation of PAHs are still obscure. The significance of our study is in the identification of the function and mechanism of the efflux pump SrpABC of Pseudomonas putida strain B6-2 (DSM 28064) in the biphenyl degradation process. SrpABC is crucial for releasing the toxicity caused by intermediates that are unavoidably produced in PAH degradation, which enables an understanding of how cells maintain the intracellular balance of materials. The findings from this study provide a new perspective on PAH recalcitrance and shed light on enhancing PAH degradation by genetic engineering.
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Wordofa GG, Kristensen M, Schrübbers L, McCloskey D, Forster J, Schneider K. Quantifying the Metabolome of Pseudomonas taiwanensis VLB120: Evaluation of Hot and Cold Combined Quenching/Extraction Approaches. Anal Chem 2017; 89:8738-8747. [PMID: 28727413 DOI: 10.1021/acs.analchem.7b00793] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Absolute quantification of free intracellular metabolites is a valuable tool in both pathway discovery and metabolic engineering. In this study, we conducted a comprehensive examination of different hot and cold combined quenching/extraction approaches to extract and quantify intracellular metabolites of Pseudomonas taiwanensis (P. taiwanensis) VLB120 to provide a useful reference data set of absolute intracellular metabolite concentrations. The suitability of commonly used metabolomics tools including a pressure driven fast filtration system followed by combined quenching/extraction techniques (such as cold methanol/acetonitrile/water, hot water, and boiling ethanol/water, as well as cold ethanol/water) were tested and evaluated for P. taiwanensis VLB120 metabolome analysis. In total 94 out of 107 detected intracellular metabolites were quantified using an isotope-ratio-based approach. The quantified metabolites include amino acids, nucleotides, central carbon metabolism intermediates, redox cofactors, and others. The acquired data demonstrate that the pressure driven fast filtration approach followed by boiling ethanol quenching/extraction is the most adequate technique for P. taiwanensis VLB120 metabolome analysis based on quenching efficiency, extraction yields of metabolites, and experimental reproducibility.
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Affiliation(s)
- Gossa G Wordofa
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , DK-2800 Lyngby, Denmark
| | - Mette Kristensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , DK-2800 Lyngby, Denmark
| | - Lars Schrübbers
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , DK-2800 Lyngby, Denmark
| | - Douglas McCloskey
- Department of Bioengineering, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0412, United States
| | - Jochen Forster
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , DK-2800 Lyngby, Denmark
| | - Konstantin Schneider
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , DK-2800 Lyngby, Denmark
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Baune M, Qi Y, Scholz K, Volmer DA, Hayen H. Structural characterization of pyoverdines produced by Pseudomonas putida KT2440 and Pseudomonas taiwanensis VLB120. Biometals 2017. [PMID: 28631237 DOI: 10.1007/s10534-017-0029-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The previously unknown sequences of several pyoverdines (PVD) produced by a biotechnologically-relevant bacterium, namely, Pseudomonas taiwanensis VLB120, were characterized by high performance liquid chromatography (HPLC)-high resolution mass spectrometry (HRMS). The same structural characterization scheme was checked before by analysis of Pseudomonas sp. putida KT2440 samples with known PVDs. A new sample preparation strategy based on solid-phase extraction was developed, requiring significantly reduced sample material as compared to existing methods. Chromatographic separation was performed using hydrophilic interaction liquid chromatography with gradient elution. Interestingly, no signals for apoPVDs were detected in these analyses, only the corresponding aluminum(III) and iron(III) complexes were seen. The chromatographic separation readily enabled separation of PVD complexes according to their individual structures. HPLC-HRMS and complementary fragmentation data from collision-induced dissociation and electron capture dissociation enabled the structural characterization of the investigated pyoverdines. In Pseudomonas sp. putida KT2240 samples, the known pyoverdines G4R and G4R A were readily confirmed. No PVDs have been previously described for Pseudomonas sp. taiwanensis VLB120. In our study, we identified three new PVDs, which only differed in their acyl side chains (succinic acid, succinic amide and malic acid). Peptide sequencing by MS/MS provided the sequence Orn-Asp-OHAsn-Thr-AcOHOrn-Ser-cOHOrn. Of particular interest is the presence of OHAsn, which has not been reported as PVD constituent before.
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Affiliation(s)
- Matthias Baune
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstr. 30, 48149, Münster, Germany
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
| | - Yulin Qi
- Institute of Bioanalytical Chemistry, Saarland University, Saarbrücken, Germany
| | - Karen Scholz
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstr. 30, 48149, Münster, Germany
| | - Dietrich A Volmer
- Institute of Bioanalytical Chemistry, Saarland University, Saarbrücken, Germany
| | - Heiko Hayen
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstr. 30, 48149, Münster, Germany.
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Volmer J, Schmid A, Bühler B. The application of constitutively solvent-tolerantP. taiwanensisVLB120ΔCΔttgVfor stereospecific epoxidation of toxic styrene alleviates carrier solvent use. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201600558] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/15/2017] [Accepted: 03/24/2017] [Indexed: 01/15/2023]
Affiliation(s)
- Jan Volmer
- Chair for Bioprocess engineering; Department of Biochemical and Chemical Engineering; TU Dortmund University; Dortmund Germany
| | - Andreas Schmid
- Department Solar Materials; Helmholtz Centre for Environmental Research GmbH - UFZ; Leipzig Germany
| | - Bruno Bühler
- Department Solar Materials; Helmholtz Centre for Environmental Research GmbH - UFZ; Leipzig Germany
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30
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Martini MC, Wibberg D, Lozano M, Torres Tejerizo G, Albicoro FJ, Jaenicke S, van Elsas JD, Petroni A, Garcillán-Barcia MP, de la Cruz F, Schlüter A, Pühler A, Pistorio M, Lagares A, Del Papa MF. Genomics of high molecular weight plasmids isolated from an on-farm biopurification system. Sci Rep 2016; 6:28284. [PMID: 27321040 PMCID: PMC4913263 DOI: 10.1038/srep28284] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/31/2016] [Indexed: 12/02/2022] Open
Abstract
The use of biopurification systems (BPS) constitutes an efficient strategy to eliminate pesticides from polluted wastewaters from farm activities. BPS environments contain a high microbial density and diversity facilitating the exchange of information among bacteria, mediated by mobile genetic elements (MGEs), which play a key role in bacterial adaptation and evolution in such environments. Here we sequenced and characterized high-molecular-weight plasmids from a bacterial collection of an on-farm BPS. The high-throughput-sequencing of the plasmid pool yielded a total of several Mb sequence information. Assembly of the sequence data resulted in six complete replicons. Using in silico analyses we identified plasmid replication genes whose encoding proteins represent 13 different Pfam families, as well as proteins involved in plasmid conjugation, indicating a large diversity of plasmid replicons and suggesting the occurrence of horizontal gene transfer (HGT) events within the habitat analyzed. In addition, genes conferring resistance to 10 classes of antimicrobial compounds and those encoding enzymes potentially involved in pesticide and aromatic hydrocarbon degradation were found. Global analysis of the plasmid pool suggest that the analyzed BPS represents a key environment for further studies addressing the dissemination of MGEs carrying catabolic genes and pathway assembly regarding degradation capabilities.
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Affiliation(s)
- María C Martini
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - Daniel Wibberg
- Center for Biotechnology (CeBiTec), Bielefeld University, Institute for Genome Research and Systems Biology, D-33615 Bielefeld, Germany
| | - Mauricio Lozano
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - Gonzalo Torres Tejerizo
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - Francisco J Albicoro
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - Sebastian Jaenicke
- Center for Biotechnology (CeBiTec), Bielefeld University, Institute for Genome Research and Systems Biology, D-33615 Bielefeld, Germany
| | | | - Alejandro Petroni
- Servicio Antimicrobianos, Departamento de Bacteriología, Instituto Nacional de Enfermedades Infecciosas-ANLIS Dr. Carlos G. Malbrán, Buenos Aires, Argentina
| | - M Pilar Garcillán-Barcia
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-Consejo Superior de Investigaciones Científicas (CSIC), 39011 Santander, Spain
| | - Fernando de la Cruz
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-Consejo Superior de Investigaciones Científicas (CSIC), 39011 Santander, Spain
| | - Andreas Schlüter
- Center for Biotechnology (CeBiTec), Bielefeld University, Institute for Genome Research and Systems Biology, D-33615 Bielefeld, Germany
| | - Alfred Pühler
- Center for Biotechnology (CeBiTec), Bielefeld University, Institute for Genome Research and Systems Biology, D-33615 Bielefeld, Germany
| | - Mariano Pistorio
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - Antonio Lagares
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
| | - María F Del Papa
- Instituto de Biotecnología y Biología Molecular (IBBM), CONICET- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115 (1900) La Plata, Argentina
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Sun F, Zhou D, Wang Q, Feng J, Feng W, Luo W, Zhang D, Liu Y, Qiu X, Yin Z, Chen W, Xia P. The first report of detecting the bla SIM-2 gene and determining the complete sequence of the SIM-encoding plasmid. Clin Microbiol Infect 2016; 22:347-351. [DOI: 10.1016/j.cmi.2015.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 12/07/2015] [Accepted: 12/07/2015] [Indexed: 10/22/2022]
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Zobel S, Benedetti I, Eisenbach L, de Lorenzo V, Wierckx N, Blank LM. Tn7-Based Device for Calibrated Heterologous Gene Expression in Pseudomonas putida. ACS Synth Biol 2015; 4:1341-51. [PMID: 26133359 DOI: 10.1021/acssynbio.5b00058] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The soil bacterium Pseudomonas putida is increasingly attracting considerable interest as a platform for advanced metabolic engineering through synthetic biology approaches. However, genomic context, gene copy number, and transcription/translation interplay often introduce considerable uncertainty to the design of reliable genetic constructs. In this work, we have established a standardized heterologous expression device in which the promoter strength is the only variable; the remaining parameters of the flow have stable default values. To this end, we tailored a mini-Tn7 delivery transposon vector that inserts the constructs in a single genomic locus of P. putida's chromosome. This was then merged with a promoter insertion site, an unvarying translational coupler, and a downstream location for placing the gene(s) of interest under fixed assembly rules. This arrangement was exploited to benchmark a collection of synthetic promoters with low transcriptional noise in this bacterial host. Growth experiments and flow cytometry with single-copy promoter-GFP constructs revealed a robust, constitutive behavior of these promoters, whose strengths and properties could be faithfully compared. This standardized expression device significantly extends the repertoire of tools available for reliable metabolic engineering and other genetic enhancements of P. putida.
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Affiliation(s)
- Sebastian Zobel
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Ilaria Benedetti
- Systems
Biology Program, Centro Nacional de Biotecnologia, CSIC, C/Darwin, 3 (Campus
de Cantoblanco), Madrid 28049, Spain
| | - Lara Eisenbach
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Victor de Lorenzo
- Systems
Biology Program, Centro Nacional de Biotecnologia, CSIC, C/Darwin, 3 (Campus
de Cantoblanco), Madrid 28049, Spain
| | - Nick Wierckx
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Lars M. Blank
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
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Lindmeyer M, Jahn M, Vorpahl C, Müller S, Schmid A, Bühler B. Variability in subpopulation formation propagates into biocatalytic variability of engineered Pseudomonas putida strains. Front Microbiol 2015; 6:1042. [PMID: 26483771 PMCID: PMC4589675 DOI: 10.3389/fmicb.2015.01042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/14/2015] [Indexed: 01/01/2023] Open
Abstract
Pivotal challenges in industrial biotechnology are the identification and overcoming of cell-to-cell heterogeneity in microbial processes. While the development of subpopulations of isogenic cells in bioprocesses is well described (intra-population variability), a possible variability between genetically identical cultures growing under macroscopically identical conditions (clonal variability) is not. A high such clonal variability has been found for the recombinant expression of the styrene monooxygenase genes styAB from Pseudomonas taiwanensis VLB120 in solvent-tolerant Pseudomonas putida DOT-T1E using the alk-regulatory system from P. putida GPo1. In this study, the oxygenase subunit StyA fused to eGFP was used as readout tool to characterize the population structure in P. putida DOT-T1E regarding recombinant protein content. Flow cytometric analyses revealed that in individual cultures, at least two subpopulations with highly differing recombinant StyA-eGFP protein contents appeared (intra-population variability). Interestingly, subpopulation sizes varied from culture-to-culture correlating with the specific styrene epoxidation activity of cells derived from respective cultures (clonal variability). In addition, flow cytometric cell sorting coupled to plasmid copy number (PCN) determination revealed that detected clonal variations cannot be correlated to the PCN, but depend on the combination of the regulatory system and the host strain employed. This is, to the best of our knowledge, the first work reporting that intra-population variability (with differing protein contents in the presented case study) causes clonal variability of genetically identical cultures. Respective impacts on bioprocess reliability and performance and strategies to overcome respective reliability issues are discussed.
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Affiliation(s)
- Martin Lindmeyer
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany
| | - Michael Jahn
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Carsten Vorpahl
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Susann Müller
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Andreas Schmid
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany ; Helmholtz Centre for Environmental Research - UFZ, Department of Solar Materials Leipzig, Germany
| | - Bruno Bühler
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany ; Helmholtz Centre for Environmental Research - UFZ, Department of Solar Materials Leipzig, Germany
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Genome Sequence of the Urethral Isolate Pseudomonas aeruginosa RN21. GENOME ANNOUNCEMENTS 2015; 3:3/4/e00788-15. [PMID: 26184943 PMCID: PMC4505131 DOI: 10.1128/genomea.00788-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudomonas aeruginosa is known to cause complicated urinary tract infections (UTI). The improved 7.0-Mb draft genome sequence of P. aeruginosa RN21, isolated from a patient with an acute UTI, was determined. It carries three (pro)phage genomes, genes for two restriction/modification systems, and a clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system.
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Vallon T, Simon O, Rendgen-Heugle B, Frana S, Mückschel B, Broicher A, Siemann-Herzberg M, Pfannenstiel J, Hauer B, Huber A, Breuer M, Takors R. Applying systems biology tools to studyn-butanol degradation inPseudomonas putidaKT2440. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400051] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Affiliation(s)
- Tobias Vallon
- Institute of Biochemical Engineering; University of Stuttgart; Stuttgart Germany
| | - Oliver Simon
- Proteomics Core Facility of the Life Science Center; University of Hohenheim; Stuttgart Germany
| | - Beate Rendgen-Heugle
- Institute of Biochemical Engineering; University of Stuttgart; Stuttgart Germany
| | - Sabine Frana
- Institute of Biochemical Engineering; University of Stuttgart; Stuttgart Germany
| | - Björn Mückschel
- Institute of Technical Biochemistry; University of Stuttgart; Stuttgart Germany
| | - Alexander Broicher
- Institute of Biochemical Engineering; University of Stuttgart; Stuttgart Germany
| | | | - Jens Pfannenstiel
- Proteomics Core Facility of the Life Science Center; University of Hohenheim; Stuttgart Germany
| | - Bernhard Hauer
- Institute of Technical Biochemistry; University of Stuttgart; Stuttgart Germany
| | - Achim Huber
- Proteomics Core Facility of the Life Science Center; University of Hohenheim; Stuttgart Germany
| | - Michael Breuer
- BASF SE; Fine Chemicals and Biocatalysis Research; Ludwigshafen Germany
| | - Ralf Takors
- Institute of Biochemical Engineering; University of Stuttgart; Stuttgart Germany
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Lindmeyer M, Meyer D, Kuhn D, Bühler B, Schmid A. Making variability less variable: matching expression system and host for oxygenase-based biotransformations. ACTA ACUST UNITED AC 2015; 42:851-66. [DOI: 10.1007/s10295-015-1615-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 03/26/2015] [Indexed: 01/11/2023]
Abstract
Abstract
Variability in whole-cell biocatalyst performance represents a critical aspect for stable and productive bioprocessing. In order to investigate whether and how oxygenase-catalyzed reactions are affected by such variability issues in solvent-tolerant Pseudomonas, different inducers, expression systems, and host strains were tested for the reproducibility of xylene and styrene monooxygenase catalyzed hydroxylation and epoxidation reactions, respectively. Significantly higher activity variations were found for biocatalysts based on solvent-tolerant Pseudomonas putida DOT-TIE and S12 compared with solvent-sensitive P. putida KT2440, Escherichia coli JM101, and solvent-tolerant Pseudomonas taiwanensis VLB120. Specific styrene epoxidation rates corresponded to cellular styrene monooxygenase contents. Detected variations in activity strictly depended on the type of regulatory system employed, being high with the alk- and low with the lac-system. These results show that the occurrence of clonal variability in recombinant gene expression in Pseudomonas depends on the combination of regulatory system and host strain, does not correlate with a general phenotype such as solvent tolerance, and must be evaluated case by case.
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Affiliation(s)
- Martin Lindmeyer
- grid.5675.1 0000000104169637 Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering TU Dortmund University Emil-Figge-Strasse 66 44227 Dortmund Germany
| | - Daniel Meyer
- grid.5675.1 0000000104169637 Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering TU Dortmund University Emil-Figge-Strasse 66 44227 Dortmund Germany
- grid.5801.c 0000000121562780 Department of Biosystems Science and Engineering ETH Zürich Mattenstrasse 26 4058 Basel Switzerland
| | - Daniel Kuhn
- grid.5675.1 0000000104169637 Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering TU Dortmund University Emil-Figge-Strasse 66 44227 Dortmund Germany
- grid.419481.1 0000 0001 1515 9979 ESBATech, a Novartis company Wagistrasse 12 8952 Zürich-Schlieren Switzerland
| | - Bruno Bühler
- grid.5675.1 0000000104169637 Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering TU Dortmund University Emil-Figge-Strasse 66 44227 Dortmund Germany
- grid.7492.8 0000000404923830 Department Solar Materials Center for Environmental Research - UFZ GmbH Permoser Strasse 15 04318 Leipzig Germany
| | - Andreas Schmid
- grid.5675.1 0000000104169637 Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering TU Dortmund University Emil-Figge-Strasse 66 44227 Dortmund Germany
- grid.7492.8 0000000404923830 Department Solar Materials Center for Environmental Research - UFZ GmbH Permoser Strasse 15 04318 Leipzig Germany
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A three-step method for analysing bacterial biofilm formation under continuous medium flow. Appl Microbiol Biotechnol 2015; 99:6035-47. [PMID: 25936379 DOI: 10.1007/s00253-015-6628-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/15/2015] [Accepted: 04/18/2015] [Indexed: 10/23/2022]
Abstract
For the investigation and comparison of microbial biofilms, a variety of analytical methods have been established, all focusing on different growth stages and application areas of biofilms. In this study, a novel quantitative assay for analysing biofilm maturation under the influence of continuous flow conditions was developed using the interesting biocatalyst Pseudomonas taiwanensis VLB120. In contrast to other tubular-based assay systems, this novel assay format delivers three readouts using a single setup in a total assay time of 40 h. It combines morphotype analysis of biofilm colonies with the direct quantification of biofilm biomass and pellicle formation on an air/liquid interphase. Applying the Tube-Assay, the impact of the second messenger cyclic diguanylate on biofilm formation of P. taiwanensis VLB120 was investigated. To this end, 41 deletions of genes encoding for protein homologues to diguanylate cyclase and phosphodiesterase were generated in the genome of P. taiwanensis VLB120. Subsequently, the biofilm formation of the resulting mutants was analysed using the Tube-Assay. In more than 60 % of the mutants, a significantly altered biofilm formation as compared to the parent strain was detected. Furthermore, the potential of the proposed Tube-Assay was validated by investigating the biofilms of several other bacterial species.
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Genome Sequence of the Urethral Catheter Isolate Pseudomonas aeruginosa MH19. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00115-15. [PMID: 25767242 PMCID: PMC4357764 DOI: 10.1128/genomea.00115-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Pseudomonas aeruginosa is a frequent agent of complicated catheter-associated urinary tract infections (CAUTIs). Here, we present the improved 7.1-Mb draft genome sequence of P. aeruginosa MH19, which was isolated from a patient with an acute hospital-acquired CAUTI. It includes unique genes not represented in other P. aeruginosa genomes.
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Engineering of Pseudomonas taiwanensis VLB120 for constitutive solvent tolerance and increased specific styrene epoxidation activity. Appl Environ Microbiol 2014; 80:6539-48. [PMID: 25128338 DOI: 10.1128/aem.01940-14] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The application of whole cells as biocatalysts is often limited by the toxicity of organic solvents, which constitute interesting substrates/products or can be used as a second phase for in situ product removal and as tools to control multistep biocatalysis. Solvent-tolerant bacteria, especially Pseudomonas strains, are proposed as promising hosts to overcome such limitations due to their inherent solvent tolerance mechanisms. However, potential industrial applications suffer from tedious, unproductive adaptation processes, phenotypic variability, and instable solvent-tolerant phenotypes. In this study, genes described to be involved in solvent tolerance were identified in Pseudomonas taiwanensis VLB120, and adaptive solvent tolerance was proven by cultivation in the presence of 1% (vol/vol) toluene. Deletion of ttgV, coding for the specific transcriptional repressor of solvent efflux pump TtgGHI gene expression, led to constitutively solvent-tolerant mutants of P. taiwanensis VLB120 and VLB120ΔC. Interestingly, the increased amount of solvent efflux pumps enhanced not only growth in the presence of toluene and styrene but also the biocatalytic performance in terms of stereospecific styrene epoxidation, although proton-driven solvent efflux is expected to compete with the styrene monooxygenase for metabolic energy. Compared to that of the P. taiwanensis VLB120ΔC parent strain, the maximum specific epoxidation activity of P. taiwanensis VLB120ΔCΔttgV doubled to 67 U/g of cells (dry weight). This study shows that solvent tolerance mechanisms, e.g., the solvent efflux pump TtgGHI, not only allow for growth in the presence of organic compounds but can also be used as tools to improve redox biocatalysis involving organic solvents.
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Köhler KAK, Blank LM, Frick O, Schmid A. D-Xylose assimilation via the Weimberg pathway by solvent-tolerant Pseudomonas taiwanensis VLB120. Environ Microbiol 2014; 17:156-70. [PMID: 24934825 DOI: 10.1111/1462-2920.12537] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 06/09/2014] [Indexed: 11/28/2022]
Abstract
The natural ability of Pseudomonas taiwanensis VLB120 to use xylose as sole carbon and energy source offers a high potential for sustainable industrial biotechnology. In general, three xylose assimilation routes are reported for bacteria. To elaborate the metabolic capacity of P. taiwanensis VLB120 and to identify potential targets for metabolic engineering, an in silico/in vivo experiment was designed, allowing for discrimination between these pathways. Kinetics of glucose and xylose degradation in P. taiwanensis VLB120 was determined and the underlying stoichiometry was investigated by genome-based metabolic modelling and tracer studies using stable isotope labelling. Additionally, reverse transcription quantitative polymerase chain reaction experiments have been performed to link physiology to the genomic inventory. Based on in silico experiments, a labelling strategy was developed, ensuring a measurable and unique (13) C-labelling distribution in proteinogenic amino acids for every possible distribution between the different xylose metabolization routes. A comparison with in vivo results allows the conclusion that xylose is metabolized by P. taiwanensis VLB120 via the Weimberg pathway. Transcriptomic and physiological studies point to the biotransformation of xylose to xylonate by glucose dehydrogenase. The kinetics of this enzyme is also responsible for the preference of glucose as carbon source by cells growing in the presence of glucose and xylose.
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Affiliation(s)
- Kirsten A K Köhler
- Laboratory of Chemical Biotechnology, TU Dortmund University, Emil-Figge-Str. 66, Dortmund, D-44227, Germany
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Arora PK, Bae H. Integration of bioinformatics to biodegradation. Biol Proced Online 2014; 16:8. [PMID: 24808763 PMCID: PMC4012781 DOI: 10.1186/1480-9222-16-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 04/19/2014] [Indexed: 12/22/2022] Open
Abstract
Bioinformatics and biodegradation are two primary scientific fields in applied microbiology and biotechnology. The present review describes development of various bioinformatics tools that may be applied in the field of biodegradation. Several databases, including the University of Minnesota Biocatalysis/Biodegradation database (UM-BBD), a database of biodegradative oxygenases (OxDBase), Biodegradation Network-Molecular Biology Database (Bionemo) MetaCyc, and BioCyc have been developed to enable access to information related to biochemistry and genetics of microbial degradation. In addition, several bioinformatics tools for predicting toxicity and biodegradation of chemicals have been developed. Furthermore, the whole genomes of several potential degrading bacteria have been sequenced and annotated using bioinformatics tools.
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Affiliation(s)
- Pankaj Kumar Arora
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea
| | - Hanhong Bae
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea
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