1
|
Re A, Mazzoli R. Current progress on engineering microbial strains and consortia for production of cellulosic butanol through consolidated bioprocessing. Microb Biotechnol 2022; 16:238-261. [PMID: 36168663 PMCID: PMC9871528 DOI: 10.1111/1751-7915.14148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/01/2022] [Accepted: 09/07/2022] [Indexed: 01/27/2023] Open
Abstract
In the last decades, fermentative production of n-butanol has regained substantial interest mainly owing to its use as drop-in-fuel. The use of lignocellulose as an alternative to traditional acetone-butanol-ethanol fermentation feedstocks (starchy biomass and molasses) can significantly increase the economic competitiveness of biobutanol over production from non-renewable sources (petroleum). However, the low cost of lignocellulose is offset by its high recalcitrance to biodegradation which generally requires chemical-physical pre-treatment and multiple bioreactor-based processes. The development of consolidated processing (i.e., single-pot fermentation) can dramatically reduce lignocellulose fermentation costs and promote its industrial application. Here, strategies for developing microbial strains and consortia that feature both efficient (hemi)cellulose depolymerization and butanol production will be depicted, that is, rational metabolic engineering of native (hemi)cellulolytic or native butanol-producing or other suitable microorganisms; protoplast fusion of (hemi)cellulolytic and butanol-producing strains; and co-culture of (hemi)cellulolytic and butanol-producing microbes. Irrespective of the fermentation feedstock, biobutanol production is inherently limited by the severe toxicity of this solvent that challenges process economic viability. Hence, an overview of strategies for developing butanol hypertolerant strains will be provided.
Collapse
Affiliation(s)
- Angela Re
- Centre for Sustainable Future TechnologiesFondazione Istituto Italiano di TecnologiaTorinoItaly,Department of Applied Science and TechnologyPolitecnico di TorinoTurinItaly
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems BiologyUniversity of TorinoTorinoItaly
| |
Collapse
|
2
|
Liu M, Wang S, Yang M, Ning X, Nan Z. Experimental study on treatment of heavy metal-contaminated soil by manganese-oxidizing bacteria. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:5526-5540. [PMID: 34424469 DOI: 10.1007/s11356-021-15475-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
There are many studies on the treatment of heavy metals by manganese-oxidizing bacteria and the reaction is good; the problem of compound pollution of heavy metals in soil has been difficult to solve. In this study, the application of manganese-oxidizing bacteria in soil was studied. The tolerance of manganese-oxidizing strains (Pseudomonas taiwanensis) to environmental conditions and the treatment effect of heavy metals As, Pb, and Cd in aqueous solution were investigated, and the effect of iron-manganese ratio on the treatment effect was discussed. The results showed that the suitable pH conditions for the growth of P. taiwanensis were 5-9, and the salt tolerance was 6% (by sodium chloride). The tolerant concentrations for heavy metals As(V) and Mn(II) were 500 mg L-1 and 120 mg L-1, respectively. The strains were enriched by nutrient broth medium. After the logarithmic phase, the bacterial suspension was mixed with ATCC#279 medium at a ratio of 1:10, and a certain amount (10 mg L-1) of Mn(II) was added. The results of As, Pb, and Cd removal in the composite polluted water phase were 22.09%, 30.75%, and 35.33%, respectively. The molar ratio of manganese and iron affected the removal efficiency of single arsenic, the highest efficiency is 68%, and the ratio of iron to manganese is 1:5. However, when the soil was treated by the same method, the results showed that not all metals were passivated, such as Cu. At the same time, for As, Pb, and Cd, the treatment effects in soil were worse than those in water, perhaps more consideration should be given to environmental conditions, such as soil moisture and temperature, when manganese-oxidizing bacteria are used to treat soil.
Collapse
Affiliation(s)
- Mengbo Liu
- College of Earth and Environmental Sciences, Lanzhou University, 222 Tianshui South Road, Lanzhou, 730000, China
| | - Shengli Wang
- College of Earth and Environmental Sciences, Lanzhou University, 222 Tianshui South Road, Lanzhou, 730000, China.
| | - Meng Yang
- College of Earth and Environmental Sciences, Lanzhou University, 222 Tianshui South Road, Lanzhou, 730000, China
| | - Xiang Ning
- College of Earth and Environmental Sciences, Lanzhou University, 222 Tianshui South Road, Lanzhou, 730000, China
| | - Zhongren Nan
- College of Earth and Environmental Sciences, Lanzhou University, 222 Tianshui South Road, Lanzhou, 730000, China
| |
Collapse
|
3
|
Costa P, Usai G, Re A, Manfredi M, Mannino G, Bertea CM, Pessione E, Mazzoli R. Clostridium cellulovorans Proteomic Responses to Butanol Stress. Front Microbiol 2021; 12:674639. [PMID: 34367082 PMCID: PMC8336468 DOI: 10.3389/fmicb.2021.674639] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/14/2021] [Indexed: 12/16/2022] Open
Abstract
Combination of butanol-hyperproducing and hypertolerant phenotypes is essential for developing microbial strains suitable for industrial production of bio-butanol, one of the most promising liquid biofuels. Clostridium cellulovorans is among the microbial strains with the highest potential for direct production of n-butanol from lignocellulosic wastes, a process that would significantly reduce the cost of bio-butanol. However, butanol exhibits higher toxicity compared to ethanol and C. cellulovorans tolerance to this solvent is low. In the present investigation, comparative gel-free proteomics was used to study the response of C. cellulovorans to butanol challenge and understand the tolerance mechanisms activated in this condition. Sequential Window Acquisition of all Theoretical fragment ion spectra Mass Spectrometry (SWATH-MS) analysis allowed identification and quantification of differentially expressed soluble proteins. The study data are available via ProteomeXchange with the identifier PXD024183. The most important response concerned modulation of protein biosynthesis, folding and degradation. Coherent with previous studies on other bacteria, several heat shock proteins (HSPs), involved in protein quality control, were up-regulated such as the chaperones GroES (Cpn10), Hsp90, and DnaJ. Globally, our data indicate that protein biosynthesis is reduced, likely not to overload HSPs. Several additional metabolic adaptations were triggered by butanol exposure such as the up-regulation of V- and F-type ATPases (involved in ATP synthesis/generation of proton motive force), enzymes involved in amino acid (e.g., arginine, lysine, methionine, and branched chain amino acids) biosynthesis and proteins involved in cell envelope re-arrangement (e.g., the products of Clocel_4136, Clocel_4137, Clocel_4144, Clocel_4162 and Clocel_4352, involved in the biosynthesis of saturated fatty acids) and a redistribution of carbon flux through fermentative pathways (acetate and formate yields were increased and decreased, respectively). Based on these experimental findings, several potential gene targets for metabolic engineering strategies aimed at improving butanol tolerance in C. cellulovorans are suggested. This includes overexpression of HSPs (e.g., GroES, Hsp90, DnaJ, ClpC), RNA chaperone Hfq, V- and F-type ATPases and a number of genes whose function in C. cellulovorans is currently unknown.
Collapse
Affiliation(s)
- Paolo Costa
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Giulia Usai
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy.,Centre for Sustainable Future Technologies, Fondazione Istituto Italiano di Tecnologia, Turin, Italy.,Department of Applied Science and Technology, Politecnico di Torino, Turin, Italy
| | - Angela Re
- Centre for Sustainable Future Technologies, Fondazione Istituto Italiano di Tecnologia, Turin, Italy
| | - Marcello Manfredi
- Center for Translational Research on Autoimmune and Allergic Diseases, Università del Piemonte Orientale, Novara, Italy.,Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Giuseppe Mannino
- Plant Physiology Unit, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Cinzia Margherita Bertea
- Plant Physiology Unit, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Enrica Pessione
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| |
Collapse
|
4
|
Exposure to 1-Butanol Exemplifies the Response of the Thermoacidophilic Archaeon Sulfolobus acidocaldarius to Solvent Stress. Appl Environ Microbiol 2021; 87:AEM.02988-20. [PMID: 33741627 PMCID: PMC8208165 DOI: 10.1128/aem.02988-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/09/2021] [Indexed: 12/18/2022] Open
Abstract
Sulfolobus acidocaldarius is a thermoacidophilic crenarchaeon with optimal growth at 80°C and pH 2 to 3. Due to its unique physiological properties, allowing life at environmental extremes, and the recent availability of genetic tools, this extremophile has received increasing interest for biotechnological applications. In order to elucidate the potential of tolerating process-related stress conditions, we investigated the response of S. acidocaldarius toward the industrially relevant organic solvent 1-butanol. In response to butanol exposure, biofilm formation of S. acidocaldarius was enhanced and occurred at up to 1.5% (vol/vol) 1-butanol, while planktonic growth was observed at up to 1% (vol/vol) 1-butanol. Confocal laser-scanning microscopy revealed that biofilm architecture changed with the formation of denser and higher tower-like structures. Concomitantly, changes in the extracellular polymeric substances with enhanced carbohydrate and protein content were determined in 1-butanol-exposed biofilms. Using scanning electron microscopy, three different cell morphotypes were observed in response to 1-butanol. Transcriptome and proteome analyses were performed comparing the response of planktonic and biofilm cells in the absence and presence of 1-butanol. In response to 1% (vol/vol) 1-butanol, transcript levels of genes encoding motility and cell envelope structures, as well as membrane proteins, were reduced. Cell division and/or vesicle formation were upregulated. Furthermore, changes in immune and defense systems, as well as metabolism and general stress responses, were observed. Our findings show that the extreme lifestyle of S. acidocaldarius coincided with a high tolerance to organic solvents. This study provides what may be the first insights into biofilm formation and membrane/cell stress caused by organic solvents in S. acidocaldarius IMPORTANCE Archaea are unique in terms of metabolic and cellular processes, as well as the adaptation to extreme environments. In the past few years, the development of genetic systems and biochemical, genetic, and polyomics studies has provided deep insights into the physiology of some archaeal model organisms. In this study, we used S. acidocaldarius, which is adapted to the two extremes of low pH and high temperature, to study its tolerance and robustness as well as its global cellular response toward organic solvents, as exemplified by 1-butanol. We were able to identify biofilm formation as a primary cellular response to 1-butanol. Furthermore, the triggered cell/membrane stress led to significant changes in culture heterogeneity accompanied by changes in central cellular processes, such as cell division and cellular defense systems, thus suggesting a global response for the protection at the population level.
Collapse
|
5
|
Neelakandan P, Young CC, Hameed A, Wang YN, Chen KN, Shen FT. Volatile 1-octanol of tea (Camellia sinensis L.) fuels cell division and indole-3-acetic acid production in phylloplane isolate Pseudomonas sp. NEEL19. Sci Rep 2021; 11:2788. [PMID: 33531600 PMCID: PMC7854675 DOI: 10.1038/s41598-021-82442-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 01/20/2021] [Indexed: 01/30/2023] Open
Abstract
Tea leaves possess numerous volatile organic compounds (VOC) that contribute to tea's characteristic aroma. Some components of tea VOC were known to exhibit antimicrobial activity; however, their impact on bacteria remains elusive. Here, we showed that the VOC of fresh aqueous tea leaf extract, recovered through hydrodistillation, promoted cell division and tryptophan-dependent indole-3-acetic acid (IAA) production in Pseudomonas sp. NEEL19, a solvent-tolerant isolate of the tea phylloplane. 1-octanol was identified as one of the responsible volatiles stimulating cell division, metabolic change, swimming motility, putative pili/nanowire formation and IAA production, through gas chromatography-mass spectrometry, microscopy and partition petri dish culture analyses. The bacterial metabolic responses including IAA production increased under 1-octanol vapor in a dose-dependent manner, whereas direct-contact in liquid culture failed to elicit such response. Thus, volatile 1-octanol emitting from tea leaves is a potential modulator of cell division, colonization and phytohormone production in NEEL19, possibly influencing the tea aroma.
Collapse
Affiliation(s)
- Poovarasan Neelakandan
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC
| | - Chiu-Chung Young
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC ,grid.260542.70000 0004 0532 3749Innovation and Development Center of Sustainable Agriculture (IDCSA), National Chung Hsing University, Taichung, 40227 Taiwan, ROC
| | - Asif Hameed
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC ,Yenepoya Research Centre, Yenepoya Deemed to be University, Mangalore, 575018 India
| | - Yu-Ning Wang
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC
| | - Kui-Nuo Chen
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC
| | - Fo-Ting Shen
- grid.260542.70000 0004 0532 3749Department of Soil & Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, 40227 Taiwan, ROC ,grid.260542.70000 0004 0532 3749Innovation and Development Center of Sustainable Agriculture (IDCSA), National Chung Hsing University, Taichung, 40227 Taiwan, ROC
| |
Collapse
|
6
|
Satapute P, Paidi MK, Kurjogi M, Jogaiah S. Physiological adaptation and spectral annotation of Arsenic and Cadmium heavy metal-resistant and susceptible strain Pseudomonas taiwanensis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 251:555-563. [PMID: 31108288 DOI: 10.1016/j.envpol.2019.05.054] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 05/03/2019] [Accepted: 05/12/2019] [Indexed: 06/09/2023]
Abstract
In the present study, the 16S-rRNA sequencing of heavy metal-resistant and susceptible bacterial strains isolated from the industrial and agriculture soil showed resemblance with Pseudomonas taiwanensis. Based on the growth rate, two bacterial strains SJPS_KUD54 and KUD-MBBT4 exhibited 10 ppm tolerance to Arsenic and Cadmium. These two heavy metals caused, a significant increase in stress enzymes like superoxide dismutase, catalase and glutathione S-transferase activities in SJPS_KUD54 when compared to KUD-MBBT4. Following heavy metal treatment, the atomic-force-microscopy observations showed no change in the cell-wall of SJPS_KUD54, whereas the cell-wall of KUD-MBBT4 got ruptured. Moreover, the protein-profile of SJPS_KUD54 treated with heavy metals exhibited varied patterns in comparison with untreated control. In addition, the accumulation of hydroxyl, thiol and amides were found in the SJPS_KUD54 relative to its control. Furthermore, the resistant SJPS_KUD54 strain showed a remarkable bioaccumulation properties to both Arsenic and Cadmium. Thus, it is inferred that the growth rate, stress enzymes and functional-groups play a significant role in the physiological-adaption of SJPS_KUD54 during stress conditions, which is positively involved in the prevention or repair mechanism for reducing the risks caused by heavy metal stress.
Collapse
Affiliation(s)
- Praveen Satapute
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka 580003, India
| | - Murali Krishna Paidi
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka 580003, India
| | - Mahantesh Kurjogi
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka 580003, India
| | - Sudisha Jogaiah
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka 580003, India.
| |
Collapse
|
7
|
Volke DC, Nikel PI. Getting Bacteria in Shape: Synthetic Morphology Approaches for the Design of Efficient Microbial Cell Factories. ACTA ACUST UNITED AC 2018. [DOI: 10.1002/adbi.201800111] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Daniel C. Volke
- The Novo Nordisk Foundation Center for Biosustainability; Technical University of Denmark; Kemitorvet 2800 Kgs. Lyngby Denmark
| | - Pablo I. Nikel
- The Novo Nordisk Foundation Center for Biosustainability; Technical University of Denmark; Kemitorvet 2800 Kgs. Lyngby Denmark
| |
Collapse
|
8
|
Basler G, Thompson M, Tullman-Ercek D, Keasling J. A Pseudomonas putida efflux pump acts on short-chain alcohols. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:136. [PMID: 29760777 PMCID: PMC5946390 DOI: 10.1186/s13068-018-1133-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 04/28/2018] [Indexed: 05/20/2023]
Abstract
BACKGROUND The microbial production of biofuels is complicated by a tradeoff between yield and toxicity of many fuels. Efflux pumps enable bacteria to tolerate toxic substances by their removal from the cells while bypassing the periplasm. Their use for the microbial production of biofuels can help to improve cell survival, product recovery, and productivity. However, no native efflux pump is known to act on the class of short-chain alcohols, important next-generation biofuels, and it was considered unlikely that such an efflux pump exists. RESULTS We report that controlled expression of the RND-type efflux pump TtgABC from Pseudomonas putida DOT-T1E strongly improved cell survival in highly toxic levels of the next-generation biofuels n-butanol, isobutanol, isoprenol, and isopentanol. GC-FID measurements indicated active efflux of n-butanol when the pump is expressed. Conversely, pump expression did not lead to faster growth in media supplemented with low concentrations of n-butanol and isopentanol. CONCLUSIONS TtgABC is the first native efflux pump shown to act on multiple short-chain alcohols. Its controlled expression can be used to improve cell survival and increase production of biofuels as an orthogonal approach to metabolic engineering. Together with the increased interest in P. putida for metabolic engineering due to its flexible metabolism, high native tolerance to toxic substances, and various applications of engineering its metabolism, our findings endorse the strain as an excellent biocatalyst for the high-yield production of next-generation biofuels.
Collapse
Affiliation(s)
- Georg Basler
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA USA
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Mitchell Thompson
- Department of Plant & Microbial Biology, University of California, Berkeley, CA USA
- Joint BioEnergy Institute, Emeryville, CA USA
| | - Danielle Tullman-Ercek
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL USA
- Center for Synthetic Biology, Northwestern University, Technological Institute B486, Evanston, USA
| | - Jay Keasling
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA USA
- Joint BioEnergy Institute, Emeryville, CA USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
- Novo Nordisk Foundation Center for Sustainability, Technical University of Denmark, Copenhagen, Denmark
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
Halan B, Vassilev I, Lang K, Schmid A, Buehler K. Growth of Pseudomonas taiwanensis VLB120∆C biofilms in the presence of n-butanol. Microb Biotechnol 2016; 10:745-755. [PMID: 27696696 PMCID: PMC5481524 DOI: 10.1111/1751-7915.12413] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 08/25/2016] [Accepted: 08/31/2016] [Indexed: 12/28/2022] Open
Abstract
Biocatalytic processes often encounter problems due to toxic reactants and products, which reduce biocatalyst viability. Thus, robust organisms capable of tolerating or adapting towards such compounds are of high importance. This study systematically investigated the physiological response of Pseudomonas taiwanensisVLB120∆C biofilms when exposed to n‐butanol, one of the potential next generation biofuels as well as a toxic substance using microscopic and biochemical methods. Initially P. taiwanensisVLB120∆C biofilms did not show any observable growth in the presence of 3% butanol. Prolonged cultivation of 10 days led to biofilm adaptation, glucose and oxygen uptake doubled and consequently it was possible to quantify biomass. Complementing the medium with yeast extract and presumably reducing the metabolic burden caused by butanol exposure further increased the biomass yield. In course of cultivation cells reduced their size in the presence of n‐butanol which results in an enlarged surface‐to‐volume ratio and thus increased nutrient uptake. Finally, biofilm enhanced its extracellular polymeric substances (EPS) production when exposed to n‐butanol. The predominant response of these biofilms under n‐butanol stress are higher energy demand, increased biomass yield upon medium complements, larger surface‐to‐volume ratio and enhanced EPS production. Although we observed a distinct increase in biomass in the presence of 3% butanol it was not possible to cultivate P. taiwanensisVLB120∆C biofilms at higher n‐butanol concentrations. Thereby this study shows that biofilms are not per se tolerant against solvents, and need to adapt to toxic n‐butanol concentrations.
Collapse
Affiliation(s)
- Babu Halan
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ GmbH, Permoserstraße 15, 04318, Leipzig, Germany
| | - Igor Vassilev
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 66, 44227, Dortmund, Germany
| | - Karsten Lang
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 66, 44227, Dortmund, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ GmbH, Permoserstraße 15, 04318, Leipzig, Germany
| | - Katja Buehler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ GmbH, Permoserstraße 15, 04318, Leipzig, Germany
| |
Collapse
|