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Zhu C, Wang Z, Zhou X, Wu Y, Kang W, Wu R, Xue C. Elucidating the Biosynthesis and Function of an Autoinducing Peptide in Clostridium acetobutylicum. Angew Chem Int Ed Engl 2025; 64:e202500904. [PMID: 39932863 DOI: 10.1002/anie.202500904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2025] [Revised: 02/10/2025] [Accepted: 02/11/2025] [Indexed: 02/13/2025]
Abstract
Clostridia produce autoinducing peptides (AIPs) regulated by the accessory gene regulator (Agr) quorum sensing system, playing a critical role in intercellular communication. However, the biosynthetic pathway and regulatory functions of clostridial AIPs remain inadequately characterized. In this study, we employed chemical quantification, genetic investigations, and in vitro reconstitution experiments to elucidate the native Ca-AIP in Clostridium acetobutylicum, a prominent industrial producer of acetone, butanol, and ethanol. Our findings identified a signal peptidase (Cac1760) and two CAAX metalloproteases (Cac0077 and Cac2478) as key players in N-terminal cleavage, while AgrB was found to be essential for C-terminal processing during Ca-AIP biosynthesis. Notably, overexpression of agrBD led to a 4.4-fold enhancement in Ca-AIP formation, which corresponded with an increase in butanol production from 12.5 to 14.9 g/L, while preserving vegetative cell morphology. The direct involvement of Ca-AIP in both butanol production and maintenance of cell morphology was further validated through exogenous supplementation. Collectively, these results provide novel insights into the biosynthesis of AIPs and propose a promising strategy for optimizing microbial processes in industrial applications.
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Affiliation(s)
- Chao Zhu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
| | - Zixuan Wang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
| | - Xiaoyu Zhou
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Youduo Wu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
- Ningbo Institute of Dalian, University of Technology, Ningbo, 315016, China
| | - Wei Kang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
- Ningbo Institute of Dalian, University of Technology, Ningbo, 315016, China
| | - Ren'an Wu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Chuang Xue
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
- Ningbo Institute of Dalian, University of Technology, Ningbo, 315016, China
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Koppova K, Burianova L, Patakova P, Branska B. Lignocellulose-derived inhibitors can extend residence of Clostridium beijerinckii in active solventogenic state. BIORESOUR BIOPROCESS 2025; 12:31. [PMID: 40205254 PMCID: PMC11982004 DOI: 10.1186/s40643-025-00871-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2025] [Accepted: 03/29/2025] [Indexed: 04/11/2025] Open
Abstract
Lignocellulose is a promising renewable resource for producing platform chemicals, such as acetone, butanol, and ethanol, via ABE fermentation by solventogenic clostridia. This study investigates the effects of common lignocellulose derived inhibitory compounds: ferulic acid, coumaric acid, and furfural on Clostridium beijerinckii. Dual-staining with propidium iodide and CFDA, combined with flow cytometry, was employed to assess physiological variability. The results showed that phenolic acid-induced stress helped maintain a higher proportion of viable cells during the production phase, enhancing solvent yields and reducing sporulation. At 0.4 g/L, ferulic and coumaric acids did not reduce cell viability; however, coumaric acid exposure led to an acid-crash profile. Conversely, a more robust inoculum exposed to both phenolic acids simultaneously exhibited effects similar to ferulic acid alone, including slower viability decline, reduced growth and sporulation, and improved solvent production. Furfural exposure at 1.5 g/L resulted in immediate viability loss in 20% of the population, though the overall decline accompanied by the highest sporulation rate occurred later than in the control. Additionally, furfural transformation was slower, suppressing butyrate production and reducing solvent production by 13%. This study suggests that delaying cell death mechanism may explain the stimulatory effects of inhibitors, advancing lignocellulose use in the future.
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Affiliation(s)
- K Koppova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technická 5, Prague, 16628, Czech Republic
| | - L Burianova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technická 5, Prague, 16628, Czech Republic
| | - P Patakova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technická 5, Prague, 16628, Czech Republic
| | - B Branska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technická 5, Prague, 16628, Czech Republic.
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Kinetics of ABE fermentation considering the different phenotypes present in a batch culture of Clostridium beijerinckii NCIMB-8052. ELECTRON J BIOTECHN 2021. [DOI: 10.1016/j.ejbt.2021.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Branska B, Vasylkivska M, Raschmanova H, Jureckova K, Sedlar K, Provaznik I, Patakova P. Changes in efflux pump activity of Clostridium beijerinckii throughout ABE fermentation. Appl Microbiol Biotechnol 2021; 105:877-889. [PMID: 33409609 DOI: 10.1007/s00253-020-11072-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 12/05/2020] [Accepted: 12/17/2020] [Indexed: 01/08/2023]
Abstract
Pumping toxic substances through a cytoplasmic membrane by protein transporters known as efflux pumps represents one bacterial mechanism involved in the stress response to the presence of toxic compounds. The active efflux might also take part in exporting low-molecular-weight alcohols produced by intrinsic cell metabolism; in the case of solventogenic clostridia, predominantly acetone, butanol and ethanol (ABE). However, little is known about this active efflux, even though some evidence exists that membrane pumps might be involved in solvent tolerance. In this study, we investigated changes in overall active efflux during ABE fermentation, employing a flow cytometric protocol adjusted for Clostridia and using ethidium bromide (EB) as a fluorescence marker for quantification of direct efflux. A fluctuation in efflux during the course of standard ABE fermentation was observed, with a maximum reached during late acidogenesis, a high efflux rate during early and mid-solventogenesis and an apparent decrease in EB efflux rate in late solventogenesis. The fluctuation in efflux activity was in accordance with transcriptomic data obtained for various membrane exporters in a former study. Surprisingly, under altered cultivation conditions, when solvent production was attenuated, and extended acidogenesis was promoted, stable low efflux activity was reached after an initial peak that appeared in the stage comparable to standard ABE fermentation. This study confirmed that efflux pump activity is not constant during ABE fermentation and suggests that undisturbed solvent production might be a trigger for activation of pumps involved in solvent efflux. KEY POINTS: • Flow cytometric assay for efflux quantification in Clostridia was established. • Efflux rate peaked in late acidogenesis and in early solventogenesis. • Impaired solventogenesis led to an overall decrease in efflux.
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Affiliation(s)
- Barbora Branska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28, Prague, Czech Republic.
| | - Maryna Vasylkivska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28, Prague, Czech Republic
| | - Hana Raschmanova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28, Prague, Czech Republic
| | - Katerina Jureckova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 12, 616 00, Brno, Czech Republic
| | - Karel Sedlar
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 12, 616 00, Brno, Czech Republic
| | - Ivo Provaznik
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 12, 616 00, Brno, Czech Republic
| | - Petra Patakova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28, Prague, Czech Republic
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González-Peñas H, Lu-Chau TA, Eibes G, Lema JM. Energy requirements and economics of acetone–butanol–ethanol (ABE) extractive fermentation: a solvent-based comparative assessment. Bioprocess Biosyst Eng 2020; 43:2269-2281. [DOI: 10.1007/s00449-020-02412-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 07/17/2020] [Indexed: 02/08/2023]
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Patakova P, Kolek J, Sedlar K, Koscova P, Branska B, Kupkova K, Paulova L, Provaznik I. Comparative analysis of high butanol tolerance and production in clostridia. Biotechnol Adv 2018; 36:721-738. [DOI: 10.1016/j.biotechadv.2017.12.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 12/05/2017] [Accepted: 12/12/2017] [Indexed: 12/24/2022]
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Branska B, Pechacova Z, Kolek J, Vasylkivska M, Patakova P. Flow cytometry analysis of Clostridium beijerinckii NRRL B-598 populations exhibiting different phenotypes induced by changes in cultivation conditions. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:99. [PMID: 29632557 PMCID: PMC5887253 DOI: 10.1186/s13068-018-1096-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/26/2018] [Indexed: 05/08/2023]
Abstract
BACKGROUND Biobutanol production by clostridia via the acetone-butanol-ethanol (ABE) pathway is a promising future technology in bioenergetics , but identifying key regulatory mechanisms for this pathway is essential in order to construct industrially relevant strains with high tolerance and productivity. We have applied flow cytometric analysis to C. beijerinckii NRRL B-598 and carried out comparative screening of physiological changes in terms of viability under different cultivation conditions to determine its dependence on particular stages of the life cycle and the concentration of butanol. RESULTS Dual staining by propidium iodide (PI) and carboxyfluorescein diacetate (CFDA) provided separation of cells into four subpopulations with different abilities to take up PI and cleave CFDA, reflecting different physiological states. The development of a staining pattern during ABE fermentation showed an apparent decline in viability, starting at the pH shift and onset of solventogenesis, although an appreciable proportion of cells continued to proliferate. This was observed for sporulating as well as non-sporulating phenotypes at low solvent concentrations, suggesting that the increase in percentage of inactive cells was not a result of solvent toxicity or a transition from vegetative to sporulating stages. Additionally, the sporulating phenotype was challenged with butanol and cultivation with a lower starting pH was performed; in both these experiments similar trends were obtained-viability declined after the pH breakpoint, independent of the actual butanol concentration in the medium. Production characteristics of both sporulating and non-sporulating phenotypes were comparable, showing that in C. beijerinckii NRRL B-598, solventogenesis was not conditional on sporulation. CONCLUSION We have shown that the decline in C. beijerinckii NRRL B-598 culture viability during ABE fermentation was not only the result of accumulated toxic metabolites, but might also be associated with a special survival strategy triggered by pH change.
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Affiliation(s)
- Barbora Branska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Zora Pechacova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Jan Kolek
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Maryna Vasylkivska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Petra Patakova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
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Heins AL, Weuster-Botz D. Population heterogeneity in microbial bioprocesses: origin, analysis, mechanisms, and future perspectives. Bioprocess Biosyst Eng 2018. [PMID: 29541890 DOI: 10.1007/s00449-018-1922-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Population heterogeneity is omnipresent in all bioprocesses even in homogenous environments. Its origin, however, is only so well understood that potential strategies like bet-hedging, noise in gene expression and division of labour that lead to population heterogeneity can be derived from experimental studies simulating the dynamics in industrial scale bioprocesses. This review aims at summarizing the current state of the different parts of single cell studies in bioprocesses. This includes setups to visualize different phenotypes of single cells, computational approaches connecting single cell physiology with environmental influence and special cultivation setups like scale-down reactors that have been proven to be useful to simulate large-scale conditions. A step in between investigation of populations and single cells is studying subpopulations with distinct properties that differ from the rest of the population with sub-omics methods which are also presented here. Moreover, the current knowledge about population heterogeneity in bioprocesses is summarized for relevant industrial production hosts and mixed cultures, as they provide the unique opportunity to distribute metabolic burden and optimize production processes in a way that is impossible in traditional monocultures. In the end, approaches to explain the underlying mechanism of population heterogeneity and the evidences found to support each hypothesis are presented. For instance, population heterogeneity serving as a bet-hedging strategy that is used as coordinated action against bioprocess-related stresses while at the same time spreading the risk between individual cells as it ensures the survival of least a part of the population in any environment the cells encounter.
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Affiliation(s)
- Anna-Lena Heins
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstr. 15, 85748, Garching, Germany.
| | - Dirk Weuster-Botz
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstr. 15, 85748, Garching, Germany
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Outram V, Lalander CA, Lee JGM, Davies ET, Harvey AP. Applied in situ product recovery in ABE fermentation. Biotechnol Prog 2017; 33:563-579. [PMID: 28188696 PMCID: PMC5485034 DOI: 10.1002/btpr.2446] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 01/31/2017] [Indexed: 12/12/2022]
Abstract
The production of biobutanol is hindered by the product's toxicity to the bacteria, which limits the productivity of the process. In situ product recovery of butanol can improve the productivity by removing the source of inhibition. This paper reviews in situ product recovery techniques applied to the acetone butanol ethanol fermentation in a stirred tank reactor. Methods of in situ recovery include gas stripping, vacuum fermentation, pervaporation, liquid–liquid extraction, perstraction, and adsorption, all of which have been investigated for the acetone, butanol, and ethanol fermentation. All techniques have shown an improvement in substrate utilization, yield, productivity or both. Different fermentation modes favored different techniques. For batch processing gas stripping and pervaporation were most favorable, but in fed‐batch fermentations gas stripping and adsorption were most promising. During continuous processing perstraction appeared to offer the best improvement. The use of hybrid techniques can increase the final product concentration beyond that of single‐stage techniques. Therefore, the selection of an in situ product recovery technique would require comparable information on the energy demand and economics of the process. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:563–579, 2017
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Affiliation(s)
- Victoria Outram
- School of Chemical Engineering and Advanced Material, Newcastle University, Newcastle-upon-Tyne, U.K.,Green Biologics Ltd, 45A Western Avenue, Milton Park, Abingdon, Oxfordshire, U.K
| | - Carl-Axel Lalander
- Green Biologics Ltd, 45A Western Avenue, Milton Park, Abingdon, Oxfordshire, U.K
| | - Jonathan G M Lee
- School of Chemical Engineering and Advanced Material, Newcastle University, Newcastle-upon-Tyne, U.K
| | - E Timothy Davies
- Green Biologics Ltd, 45A Western Avenue, Milton Park, Abingdon, Oxfordshire, U.K
| | - Adam P Harvey
- School of Chemical Engineering and Advanced Material, Newcastle University, Newcastle-upon-Tyne, U.K
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Grisales Díaz VH, Olivar Tost G. Techno-economic analysis of extraction-based separation systems for acetone, butanol, and ethanol recovery and purification. BIORESOUR BIOPROCESS 2017; 4:12. [PMID: 28251042 PMCID: PMC5306422 DOI: 10.1186/s40643-017-0142-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 02/04/2017] [Indexed: 12/02/2022] Open
Abstract
Background Dual extraction, high-temperature extraction, mixture extraction, and oleyl alcohol extraction have been proposed in the literature for acetone, butanol, and ethanol (ABE) production. However, energy and economic evaluation under similar assumptions of extraction-based separation systems are necessary. Hence, the new process proposed in this work, direct steam distillation (DSD), for regeneration of high-boiling extractants was compared with several extraction-based separation systems. Methods The evaluation was performed under similar assumptions through simulation in Aspen Plus V7.3® software. Two end distillation systems (number of non-ideal stages between 70 and 80) were studied. Heat integration and vacuum operation of some units were proposed reducing the energy requirements. Results Energy requirement of hybrid processes, substrate concentration of 200 g/l, was between 6.4 and 8.3 MJ-fuel/kg-ABE. The minimum energy requirements of extraction-based separation systems, feeding a water concentration in the substrate equivalent to extractant selectivity, and ideal assumptions were between 2.6 and 3.5 MJ-fuel/kg-ABE, respectively. The efficiencies of recovery systems for baseline case and ideal evaluation were 0.53–0.57 and 0.81–0.84, respectively. Conclusions The main advantages of DSD were the operation of the regeneration column at atmospheric pressure, the utilization of low-pressure steam, and the low energy requirements of preheating. The in situ recovery processes, DSD, and mixture extraction with conventional regeneration were the approaches with the lowest energy requirements and total annualized costs. Electronic supplementary material The online version of this article (doi:10.1186/s40643-017-0142-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Víctor Hugo Grisales Díaz
- School of Chemical Engineering and Advanced Materials, Newcastle University, Newcastle upon Tyne, NE1 7RU UK
| | - Gerard Olivar Tost
- Control y Percepción Inteligente, Departamento de Ingeniería Eléctrica, Electrónica y Computación, Universidad Nacional de Colombia, Cra. 27 No. 64-60, Manizales, Colombia
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Xue C, Zhao J, Chen L, Yang ST, Bai F. Recent advances and state-of-the-art strategies in strain and process engineering for biobutanol production by Clostridium acetobutylicum. Biotechnol Adv 2017; 35:310-322. [DOI: 10.1016/j.biotechadv.2017.01.007] [Citation(s) in RCA: 177] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/06/2017] [Accepted: 01/25/2017] [Indexed: 12/20/2022]
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Mathematical modelling of clostridial acetone-butanol-ethanol fermentation. Appl Microbiol Biotechnol 2017; 101:2251-2271. [PMID: 28210797 PMCID: PMC5320022 DOI: 10.1007/s00253-017-8137-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/14/2017] [Accepted: 01/16/2017] [Indexed: 12/24/2022]
Abstract
Clostridial acetone-butanol-ethanol (ABE) fermentation features a remarkable shift in the cellular metabolic activity from acid formation, acidogenesis, to the production of industrial-relevant solvents, solventogensis. In recent decades, mathematical models have been employed to elucidate the complex interlinked regulation and conditions that determine these two distinct metabolic states and govern the transition between them. In this review, we discuss these models with a focus on the mechanisms controlling intra- and extracellular changes between acidogenesis and solventogenesis. In particular, we critically evaluate underlying model assumptions and predictions in the light of current experimental knowledge. Towards this end, we briefly introduce key ideas and assumptions applied in the discussed modelling approaches, but waive a comprehensive mathematical presentation. We distinguish between structural and dynamical models, which will be discussed in their chronological order to illustrate how new biological information facilitates the ‘evolution’ of mathematical models. Mathematical models and their analysis have significantly contributed to our knowledge of ABE fermentation and the underlying regulatory network which spans all levels of biological organization. However, the ties between the different levels of cellular regulation are not well understood. Furthermore, contradictory experimental and theoretical results challenge our current notion of ABE metabolic network structure. Thus, clostridial ABE fermentation still poses theoretical as well as experimental challenges which are best approached in close collaboration between modellers and experimentalists.
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García-Torreiro M, López-Abelairas M, Lu-Chau TA, Lema JM. Application of flow cytometry for monitoring the production of poly(3-hydroxybutyrate) by Halomonas boliviensis. Biotechnol Prog 2016; 33:276-284. [PMID: 27689857 DOI: 10.1002/btpr.2373] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 09/16/2016] [Indexed: 11/05/2022]
Abstract
In this study, a flow cytometry (FC) protocol was implemented to measure poly(3-hydroxybutyrate) (PHB) content in a halophilic bacterium, to have a faster and easier control of the process. The halophilic bacterium Halomonas boliviensis was stained with BODIPY 493/503 and analyzed using FC. Bacterial polymer accumulation induced by two different nutrient limitations during the operation of a 2 L bioreactor was studied using traditional gas chromatography (GC) analysis and FC. The application of this rapid and straightforward method is useful to obtain complex and precise information about PHB accumulation that could be used for the monitoring, control and optimization of the production of PHB. A clear correlation between the PHB concentration determined by GC and the fluorescence signal obtained from stained bacteria by using FC was observed. Additionally, the heterogeneity of bacterial population as a function of PHB content was measured. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:276-284, 2017.
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Affiliation(s)
- María García-Torreiro
- Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - María López-Abelairas
- Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Thelmo A Lu-Chau
- Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Juan M Lema
- Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
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Effect of nitrogen and/or oxygen concentration on poly(3-hydroxybutyrate) accumulation by Halomonas boliviensis. Bioprocess Biosyst Eng 2016; 39:1365-74. [DOI: 10.1007/s00449-016-1612-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/19/2016] [Indexed: 11/27/2022]
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15
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Kolek J, Branska B, Drahokoupil M, Patakova P, Melzoch K. Evaluation of viability, metabolic activity and spore quantity in clostridial cultures during ABE fermentation. FEMS Microbiol Lett 2016; 363:fnw031. [PMID: 26862145 DOI: 10.1093/femsle/fnw031] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/03/2016] [Indexed: 01/10/2023] Open
Abstract
Flow cytometry, in combination with fluorescent staining, was used to evaluate population heterogeneity in acetone-butanol-ethanol fermentation that was carried out with type strain Clostridium beijerinckii NCIMB 8052 and non-type C. pasteurianum NRRL B-598. A combination of propidium iodide (PI) and carboxyfluorescein diacetate (CFDA), PI plus Syto-9 and bis-oxonol (BOX) alone were employed to distinguish between active and damaged cells together with simultaneous detection of spores. These strategies provided valuable information on the physiological state of clostridia. CFDA and PI staining gave the best separation of four distinct subpopulations of enzymatically active cells, doubly stained cells, damaged cells and spores. Proportional representation of cells in particular sub-regions correlated with growth characteristics, fermentation parameters such as substrate consumption and product formation in both species under different cultivation conditions.
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Affiliation(s)
- Jan Kolek
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 16628 Prague, Czech Republic
| | - Barbora Branska
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 16628 Prague, Czech Republic
| | - Marek Drahokoupil
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 16628 Prague, Czech Republic
| | - Petra Patakova
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 16628 Prague, Czech Republic
| | - Karel Melzoch
- Department of Biotechnology, University of Chemistry and Technology Prague, Technicka 5, 16628 Prague, Czech Republic
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16
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Gallazzi A, Branska B, Marinelli F, Patakova P. Continuous production of n-butanol by Clostridium pasteurianum DSM 525 using suspended and surface-immobilized cells. J Biotechnol 2015; 216:29-35. [PMID: 26471284 DOI: 10.1016/j.jbiotec.2015.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 10/06/2015] [Accepted: 10/09/2015] [Indexed: 11/28/2022]
Abstract
For n-butanol production by Clostridium pasteurianum DSM 525, a modified reinforced Clostridium medium was used, where glucose was alternated with glycerol and two kinds of continuous fermentation were tested using suspended and surface immobilized cells on corn stover pieces. A steady state, with butanol productivity of 4.2g/Lh, was reached during the packed-bed continuous fermentation at a dilution rate of 0.44h(-1). The average n-butanol concentration, yield and the ratio of n-butanol/liquid by-products were 10.4g/L, 33 % and 2.5, respectively. Unexpectedly, during continuous fermentation with suspended cells, at a dilution rate of 0.01h(-1), steady-state was not achieved and regular oscillations occurred in all measured variables, i.e. concentrations of glycerol, products and the number of cells stained with the fluorescent dyes carboxy fluorescein diacetate and propidium iodide. A possible explanation for oscillatory/steady-state behavior of suspended/surface-attached cells, respectively, may be specific butanol toxicity (toxicity per cell), which was higher/lower in respective cases, and which might be caused by lower/higher cell numbers respectively in both systems.
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Affiliation(s)
- Alessandro Gallazzi
- Department of Biotechnology, University of Chemistry and Technology, Prague, Czech Republic; Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy; "The Protein Factory" Research Center, Politecnico of Milano, ICRM CNR Milano and University of Insubria, Varese, Italy
| | - Barbora Branska
- Department of Biotechnology, University of Chemistry and Technology, Prague, Czech Republic
| | - Flavia Marinelli
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy; "The Protein Factory" Research Center, Politecnico of Milano, ICRM CNR Milano and University of Insubria, Varese, Italy
| | - Petra Patakova
- Department of Biotechnology, University of Chemistry and Technology, Prague, Czech Republic.
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