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Yu EY, Chau JHC, Lee MMS, Koo TH, Lortz R, Lam JWY, Kwok RTK, Li Y, Tang BZ. Recyclable and Environmentally Friendly Magnetic Nanoparticles with Aggregation-Induced Emission Photosensitizer for Sustainable Bacterial Inactivation in Water. ACS NANO 2024; 18:1907-1920. [PMID: 38190607 DOI: 10.1021/acsnano.3c05941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Bacterial photodynamic inactivation based on the combined actions of photosensitizers, light, and oxygen presents a promising alternative for eliminating bacteria compared to conventional water disinfection methods. However, a significant challenge in this approach is the inability to retrieve photosensitizers after phototreatment, posing potential adverse environmental impacts. Additionally, conventional photosensitizers often exhibit limited photostability and photodynamic efficiency. This study addresses these challenges by employing an aggregation-induced emission (AIE) photosensitizer, iron oxide magnetic nanoparticles (Fe3O4 MNPs), and Pluronic F127 to fabricate AIE magnetic nanoparticles (AIE MNPs). AIE MNPs not only exhibit fluorescence imaging capabilities and superior photosensitizing ability but also demonstrate broad-spectrum bactericidal activities against both Gram-positive and Gram-negative bacteria. The controlled release of TPA-Py-PhMe and magnetic characteristics of the AIE MNPs facilitate reuse and recycling for multiple cycles of bacterial inactivation in water. Our findings contribute valuable insights into developing environmentally friendly disinfectants, emphasizing the full potential of AIE photosensitizers in photodynamic inactivation beyond biomedical applications.
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Affiliation(s)
- Eric Y Yu
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Joe H C Chau
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Michelle M S Lee
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Tsin Hei Koo
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Rolf Lortz
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Jacky W Y Lam
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Ryan T K Kwok
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Yuanyuan Li
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Ben Zhong Tang
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
- School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), Guangdong 518172, China
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2
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Pospíšil J, Schwarz M, Ziková A, Vítovská D, Hradilová M, Kolář M, Křenková A, Hubálek M, Krásný L, Vohradský J. σ E of Streptomyces coelicolor can function both as a direct activator or repressor of transcription. Commun Biol 2024; 7:46. [PMID: 38184746 PMCID: PMC10771440 DOI: 10.1038/s42003-023-05716-y] [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: 06/12/2023] [Accepted: 12/18/2023] [Indexed: 01/08/2024] Open
Abstract
σ factors are considered as positive regulators of gene expression. Here we reveal the opposite, inhibitory role of these proteins. We used a combination of molecular biology methods and computational modeling to analyze the regulatory activity of the extracytoplasmic σE factor from Streptomyces coelicolor. The direct activator/repressor function of σE was then explored by experimental analysis of selected promoter regions in vivo. Additionally, the σE interactome was defined. Taken together, the results characterize σE, its regulation, regulon, and suggest its direct inhibitory function (as a repressor) in gene expression, a phenomenon that may be common also to other σ factors and organisms.
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Affiliation(s)
- Jiří Pospíšil
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
| | - Marek Schwarz
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Alice Ziková
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Dragana Vítovská
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Miluše Hradilová
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Michal Kolář
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Alena Křenková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 542/2, 160 00, Prague 6, Czech Republic
| | - Martin Hubálek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 542/2, 160 00, Prague 6, Czech Republic
| | - Libor Krásný
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Vohradský
- Laboratory of Bioinformatics, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
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Schumacher K, Gelhausen R, Kion-Crosby W, Barquist L, Backofen R, Jung K. Ribosome profiling reveals the fine-tuned response of Escherichia coli to mild and severe acid stress. mSystems 2023; 8:e0103723. [PMID: 37909716 PMCID: PMC10746267 DOI: 10.1128/msystems.01037-23] [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: 09/26/2023] [Accepted: 09/28/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE Bacteria react very differently to survive in acidic environments, such as the human gastrointestinal tract. Escherichia coli is one of the extremely acid-resistant bacteria and has a variety of acid-defense mechanisms. Here, we provide the first genome-wide overview of the adaptations of E. coli K-12 to mild and severe acid stress at both the transcriptional and translational levels. Using ribosome profiling and RNA sequencing, we uncover novel adaptations to different degrees of acidity, including previously hidden stress-induced small proteins and novel key transcription factors for acid defense, and report mRNAs with pH-dependent differential translation efficiency. In addition, we distinguish between acid-specific adaptations and general stress response mechanisms using denoising autoencoders. This workflow represents a powerful approach that takes advantage of next-generation sequencing techniques and machine learning to systematically analyze bacterial stress responses.
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Affiliation(s)
- Kilian Schumacher
- Faculty of Biology, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Rick Gelhausen
- Bioinformatics Group, Department of Computer Science, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Willow Kion-Crosby
- Helmholtz Institute for RNA-based Infection Research (HIRI)/Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
- University of Würzburg, Faculty of Medicine, Würzburg, Germany
| | - Lars Barquist
- Helmholtz Institute for RNA-based Infection Research (HIRI)/Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
- University of Würzburg, Faculty of Medicine, Würzburg, Germany
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Kirsten Jung
- Faculty of Biology, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
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Tan R, Zhou Y, An Z, Xu Y. Cancer Is A Survival Process under Persistent Microenvironmental and Cellular Stresses. GENOMICS, PROTEOMICS & BIOINFORMATICS 2023; 21:1260-1265. [PMID: 35728722 PMCID: PMC11082257 DOI: 10.1016/j.gpb.2022.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 03/11/2022] [Accepted: 04/07/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Renbo Tan
- Cancer Systems Biology Center, China-Japan Union Hospital of Jilin University, Changchun 130000, China; College of Computer Science and Technology, Jilin University, Changchun 130000, China
| | - Yi Zhou
- Department of Biochemistry and Molecular Biology, and Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
| | - Zheng An
- Cancer Systems Biology Center, China-Japan Union Hospital of Jilin University, Changchun 130000, China; Department of Biochemistry and Molecular Biology, and Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
| | - Ying Xu
- Cancer Systems Biology Center, China-Japan Union Hospital of Jilin University, Changchun 130000, China; Department of Biochemistry and Molecular Biology, and Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA.
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Liu L, Li G, Cao H. The Multiomics Response of Bacillus subtilis to Simultaneous Genetic and Environmental Perturbations. Microorganisms 2023; 11:1949. [PMID: 37630509 PMCID: PMC10458161 DOI: 10.3390/microorganisms11081949] [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: 06/25/2023] [Revised: 07/16/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023] Open
Abstract
How bacteria respond at the systems level to both genetic and environmental perturbations imposed at the same time is one fundamental yet open question in biology. Bioengineering or synthetic biology provides an ideal system for studying such responses, as engineered strains always have genetic changes as opposed to wildtypes and are grown in conditions which often change during growth for maximal yield of desired products. So, engineered strains were used to address the outstanding question. Two Bacillus subtilis strains (MT1 and MT2) were created previously for the overproduction of N-acetylglucosamine (GlcNAc), which were grown in an environment with a carbon shift from glucose to glucose and xylose in the same culture system. We had four groups: (1) a wildtype (WT) grown with glucose at t1; (2) a WT with glucose and xylose at t2; (3) a mutant (MT1) grown with glucose at t1; and (4) MT1 with glucose and xylose at t2. By measuring transcriptomes and metabolomes, we found that GlcNAc-producing mutants, particularly MT2, had a higher yield of N-acetylglucosamine than WT but displayed a smaller maximum growth rate than the wildtype, despite MT1 reaching higher carrying capacity. Underlying the observed growth, the engineered pathways leading to N-acetylglucosamine had both higher gene expression and associated metabolite concentrations in MT1 than WT at both t1 and t2; in bioenergetics, there was higher energy supply in terms of ATP and GTP, with the energy state metric higher in MT1 than WT at both timepoints. Additionally, most top key precursor metabolites were equally abundant in MT1 and WT at either timepoints. Besides that, one prominent feature was the high consistency between transcriptomics and metabolomics in revealing the response. First, both metabolomes and transcriptomes revealed the same PCA clusters of the four groups. Second, we found that the important functions enriched both by metabolomes and transcriptomes overlapped, such as amino acid metabolism and ABC transport. Strikingly, these functions overlapped those enriched by the genes showing a high (positive or negative) correlation with metabolites. Furthermore, these functions also overlapped the enriched KEGG pathways identified using weighted gene coexpression network analysis. All these findings suggest that the responses to simultaneous genetic and environmental perturbations are well coordinated at the metabolic and transcriptional levels: they rely heavily on bioenergetics, but core metabolism does not differ much, while amino acid metabolism and ABC transport are important. This serves as a design guide for bioengineering, synthetic biology, and systems biology.
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Affiliation(s)
| | | | - Huansheng Cao
- Division of Natural and Applied Sciences, Duke Kunshan University, Suzhou 215316, China; (L.L.); (G.L.)
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Parera Olm I, Sousa DZ. Upgrading dilute ethanol to odd-chain carboxylic acids by a synthetic co-culture of Anaerotignum neopropionicum and Clostridium kluyveri. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:83. [PMID: 37194097 DOI: 10.1186/s13068-023-02336-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 05/03/2023] [Indexed: 05/18/2023]
Abstract
BACKGROUND Dilute ethanol streams generated during fermentation of biomass or syngas can be used as feedstocks for the production of higher value products. In this study, we describe a novel synthetic microbial co-culture that can effectively upgrade dilute ethanol streams to odd-chain carboxylic acids (OCCAs), specifically valerate and heptanoate. The co-culture consists of two strict anaerobic microorganisms: Anaerotignum neopropionicum, a propionigenic bacterium that ferments ethanol, and Clostridium kluyveri, well-known for its chain-elongating metabolism. In this co-culture, A. neopropionicum grows on ethanol and CO2 producing propionate and acetate, which are then utilised by C. kluyveri for chain elongation with ethanol as the electron donor. RESULTS A co-culture of A. neopropionicum and C. kluyveri was established in serum bottles with 50 mM ethanol, leading to the production of valerate (5.4 ± 0.1 mM) as main product of ethanol-driven chain elongation. In a continuous bioreactor supplied with 3.1 g ethanol L-1 d-1, the co-culture exhibited high ethanol conversion (96.6%) and produced 25% (mol/mol) valerate, with a steady-state concentration of 8.5 mM and a rate of 5.7 mmol L-1 d-1. In addition, up to 6.5 mM heptanoate was produced at a rate of 2.9 mmol L-1 d-1. Batch experiments were also conducted to study the individual growth of the two strains on ethanol. A. neopropionicum showed the highest growth rate when cultured with 50 mM ethanol (μmax = 0.103 ± 0.003 h-1) and tolerated ethanol concentrations of up to 300 mM. Cultivation experiments with C. kluyveri showed that propionate and acetate were used simultaneously for chain elongation. However, growth on propionate alone (50 mM and 100 mM) led to a 1.8-fold reduction in growth rate compared to growth on acetate. Our results also revealed sub-optimal substrate use by C. kluyveri during odd-chain elongation, where excessive ethanol was oxidised to acetate. CONCLUSIONS This study highlights the potential of synthetic co-cultivation in chain elongation processes to target the production of OCCAs. Furthermore, our findings shed light on to the metabolism of odd-chain elongation by C. kluyveri.
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Affiliation(s)
- Ivette Parera Olm
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands.
- Centre for Living Technologies, Eindhoven-Wageningen-Utrecht Alliance, Utrecht, The Netherlands.
| | - Diana Z Sousa
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
- Centre for Living Technologies, Eindhoven-Wageningen-Utrecht Alliance, Utrecht, The Netherlands
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7
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The effects of different thermal and chemical stresses on release of outer membrane vesicles (OMVs) by ClearColi™. Arch Microbiol 2022; 204:714. [DOI: 10.1007/s00203-022-03287-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 10/03/2022] [Accepted: 10/17/2022] [Indexed: 11/19/2022]
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8
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Gan Y, Bai M, Lin X, Liu K, Huang B, Jiang X, Liu Y, Gao C. Improvement of macrolactins production by the genetic adaptation of Bacillus siamensis A72 to saline stress via adaptive laboratory evolution. Microb Cell Fact 2022; 21:147. [PMID: 35854349 PMCID: PMC9294813 DOI: 10.1186/s12934-022-01871-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Macrolactins, a type of macrolide antibiotic, are toxic to the producer strains. As such, its level is usually maintained below the lethal concentration during the fermentation process. To improve the production of macrolactins, we applied adaptive laboratory evolution technology to engineer a saline-resistant mutant strain. The hypothesis that strains with saline resistance show improved macrolactins production was investigated. RESULTS Using saline stress as a selective pressure, we engineered a mutant strain with saline resistance coupled with enhanced macrolactins production within 60 days using a self-made device. As compared with the parental strain, the evolved strain produced macrolactins with 11.93% improvement in non-saline stress fermentation medium containing 50 g/L glucose, when the glucose concentration increased to 70 g/L, the evolved strain produced macrolactins with 71.04% improvement. RNA sequencing and metabolomics results revealed that amino acid metabolism was involved in the production of macrolactins in the evolved strain. Furthermore, genome sequencing of the evolved strain revealed a candidate mutation, hisDD41Y, that was causal for the improved MLNs production, it was 3.42 times higher than the control in the overexpression hisDD41Y strain. Results revealed that saline resistance protected the producer strain from feedback inhibition of end-product (macrolide antibiotic), resulting in enhanced MLNs production. CONCLUSIONS In the present work, we successfully engineered a mutant strain with enhanced macrolactins production by adaptive laboratory evolution using saline stress as a selective pressure. Based on physiological, transcriptomic and genetic analysis, amino acid metabolism was found to benefit macrolactins production improvement. Our strategy might be applicable to improve the production of other kinds of macrolide antibiotics and other toxic compounds. The identification of the hisD mutation will allow for the deduction of metabolic engineering strategies in future research.
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Affiliation(s)
- Yuman Gan
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China.
| | - Meng Bai
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China
| | - Xiao Lin
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China
| | - Kai Liu
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China
| | - Bingyao Huang
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China
| | - Xiaodong Jiang
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China
| | - Yonghong Liu
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China.
| | - Chenghai Gao
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Guangxi, 530001, People's Republic of China.
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Stark C, Münßinger S, Rosenau F, Eikmanns BJ, Schwentner A. The Potential of Sequential Fermentations in Converting C1 Substrates to Higher-Value Products. Front Microbiol 2022; 13:907577. [PMID: 35722332 PMCID: PMC9204031 DOI: 10.3389/fmicb.2022.907577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Today production of (bulk) chemicals and fuels almost exclusively relies on petroleum-based sources, which are connected to greenhouse gas release, fueling climate change. This increases the urgence to develop alternative bio-based technologies and processes. Gaseous and liquid C1 compounds are available at low cost and often occur as waste streams. Acetogenic bacteria can directly use C1 compounds like CO, CO2, formate or methanol anaerobically, converting them into acetate and ethanol for higher-value biotechnological products. However, these microorganisms possess strict energetic limitations, which in turn pose limitations to their potential for biotechnological applications. Moreover, efficient genetic tools for strain improvement are often missing. However, focusing on the metabolic abilities acetogens provide, they can prodigiously ease these technological disadvantages. Producing acetate and ethanol from C1 compounds can fuel via bio-based intermediates conversion into more energy-demanding, higher-value products, by deploying aerobic organisms that are able to grow with acetate/ethanol as carbon and energy source. Promising new approaches have become available combining these two fermentation steps in sequential approaches, either as separate fermentations or as integrated two-stage fermentation processes. This review aims at introducing, comparing, and evaluating the published approaches of sequential C1 fermentations, delivering a list of promising organisms for the individual fermentation steps and giving an overview of the existing broad spectrum of products based on acetate and ethanol. Understanding of these pioneering approaches allows collecting ideas for new products and may open avenues toward making full use of the technological potential of these concepts for establishment of a sustainable biotechnology.
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Affiliation(s)
- Christina Stark
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Sini Münßinger
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Frank Rosenau
- Institute of Pharmaceutical Biotechnology, University of Ulm, Ulm, Germany
| | - Bernhard J. Eikmanns
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
- *Correspondence: Bernhard J. Eikmanns,
| | - Andreas Schwentner
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
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Mora-Garduño JD, Tamayo-Nuñez J, Padilla-Vaca F, Ramírez-Montiel FB, Rangel-Serrano Á, Santos-Escobar F, Gutiérrez-Corona F, Páramo-Pérez I, Anaya-Velázquez F, García-Contreras R, Vargas-Maya NI, Franco B. Chromogenic Escherichia coli reporter strain for screening DNA damaging agents. AMB Express 2022; 12:2. [PMID: 34989906 PMCID: PMC8739417 DOI: 10.1186/s13568-021-01342-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 12/23/2021] [Indexed: 11/18/2022] Open
Abstract
The presence of pollutants in soil and water has given rise to diverse analytical and biological approaches to detect and measure contaminants in the environment. Using bacterial cells as reporter strains represents an advantage for detecting pollutants present in soil or water samples. Here, an Escherichia coli reporter strain expressing a chromoprotein capable of interacting with soil or water samples and responding to DNA damaging compounds is validated. The reporter strain generates a qualitative signal and is based on the expression of the coral chromoprotein AmilCP under the control of the recA promoter. This strain can be used simply by applying soil or water samples directly and rendering activation upon DNA damage. This reporter strain responds to agents that damage DNA (with an apparent detection limit of 1 µg of mitomycin C) without observable response to membrane integrity damage, protein folding or oxidative stress generating agents, in the latter case, DNA damage was observed. The developed reporter strain reported here is effective for the detection of DNA damaging agents present in soils samples. In a proof-of-concept analysis using soil containing chromium, showing activation at 15.56 mg/L of Cr(VI) present in soil and leached samples and is consistent with Cr(III) toxicity at high concentrations (130 µg). Our findings suggest that chromogenic reporter strains can be applied for simple screening, thus reducing the number of samples requiring analytical techniques.
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Eom GE, Lee H, Kim S. Development of a genome-targeting mutator for the adaptive evolution of microbial cells. Nucleic Acids Res 2021; 50:e38. [PMID: 34928386 PMCID: PMC9023256 DOI: 10.1093/nar/gkab1244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/05/2021] [Accepted: 12/03/2021] [Indexed: 11/30/2022] Open
Abstract
Methods that can randomly introduce mutations in the microbial genome have been used for classical genetic screening and, more recently, the evolutionary engineering of microbial cells. However, most methods rely on either cell-damaging agents or disruptive mutations of genes that are involved in accurate DNA replication, of which the latter requires prior knowledge of gene functions, and thus, is not easily transferable to other species. In this study, we developed a new mutator for in vivo mutagenesis that can directly modify the genomic DNA. Mutator protein, MutaEco, in which a DNA-modifying enzyme is fused to the α-subunit of Escherichia coli RNA polymerase, increases the mutation rate without compromising the cell viability and accelerates the adaptive evolution of E. coli for stress tolerance and utilization of unconventional carbon sources. This fusion strategy is expected to accommodate diverse DNA-modifying enzymes and may be easily adapted to various bacterial species.
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Affiliation(s)
- Ga-Eul Eom
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea
| | - Hyunbin Lee
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea
| | - Seokhee Kim
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea
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12
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Ren C, Zheng Y, Liu C, Mencius J, Wu Z, Quan S. Molecular Characterization of an Intrinsically Disordered Chaperone Reveals Net-Charge Regulation in Chaperone Action. J Mol Biol 2021; 434:167405. [PMID: 34914967 DOI: 10.1016/j.jmb.2021.167405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/18/2022]
Abstract
Molecular chaperones are diverse biomacromolecules involved in the maintenance of cellular protein homeostasis (proteostasis). Here we demonstrate that in contrast to most chaperones with defined three-dimensional structures, the acid-inducible protein Asr in Escherichia coli is intrinsically disordered and exhibits varied aggregation-preventing or aggregation-promoting activities, acting as a "conditionally active chaperone". Bioinformatics and experimental analyses of Asr showed that it is devoid of hydrophobic patches but rich in positive charges and local polyproline II backbone structures. Asr contributes to the integrity of the bacterial outer membrane under mildly acidic conditions in vivo and possesses chaperone activities toward model clients in vitro. Notably, its chaperone activity is dependent on the net charges of clients: on the one hand, it inhibits the aggregation of clients with similar net charges; on the other hand, it stimulates the aggregation of clients with opposite net charges. Mutational analysis confirmed that positively charged residues in Asr are essential for the varied effects on protein aggregation, suggesting that electrostatic interactions are the major driving forces underlying Asr's proteostasis-related activity. These findings present a unique example of an intrinsically disordered molecular chaperone with distinctive dual functions-as an aggregase or as a chaperone-depending on the net charges of clients.
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Affiliation(s)
- Chang Ren
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Yongxin Zheng
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Chunlan Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Jun Mencius
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Zhili Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Shu Quan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China; Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai 200237, China.
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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.
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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
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Doukyu N, Taguchi K. Involvement of catalase and superoxide dismutase in hydrophobic organic solvent tolerance of Escherichia coli. AMB Express 2021; 11:97. [PMID: 34189628 PMCID: PMC8241964 DOI: 10.1186/s13568-021-01258-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 06/16/2021] [Indexed: 12/22/2022] Open
Abstract
Escherichia coli strains are generally sensitive to hydrophobic organic solvents such as n-hexane and cyclohexane. Oxidative stress in E. coli by exposure to these hydrophobic organic solvents has been poorly understood. In the present study, we examined organic solvent tolerance and oxygen radical generation in E. coli mutants deficient in reactive oxygen species (ROS)-scavenging enzymes. The organic solvent tolerances in single gene mutants lacking genes encoding superoxide dismutase (sodA, sodB, and sodC), catalase (katE and katG), and alkyl hydroperoxide reductase (ahpCF) were similar to that of parent strain BW25113. We constructed a BW25113-based katE katG double mutant (BW25113∆katE∆katG) and sodA sodB double mutant (BW25113sodA∆sodB). These double-gene mutants were more sensitive to hydrophobic organic solvents than BW25113. In addition, the intracellular ROS levels in E. coli strains increased by the addition of n-hexane or cyclohexane. The ROS levels in BW25113∆katE∆katG and BW25113∆sodA∆sodB induced by exposure to the solvents were higher than that in BW25113. These results suggested that ROS-scavenging enzymes contribute to the maintenance of organic solvent tolerance in E. coli. In addition, the promoter activities of sodA and sodB were significantly increased by exposure to n-hexane.
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Affiliation(s)
- Noriyuki Doukyu
- Department of Life Science, Toyo University, 1-1-1 Izumino, Itakura-machi, Gunma 374-0193 Japan
- Bio-Nano Electronic Research Center, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 Japan
| | - Katsuya Taguchi
- Department of Life Science, Toyo University, 1-1-1 Izumino, Itakura-machi, Gunma 374-0193 Japan
- Bio-Nano Electronic Research Center, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 Japan
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Schalck T, den Bergh BV, Michiels J. Increasing Solvent Tolerance to Improve Microbial Production of Alcohols, Terpenoids and Aromatics. Microorganisms 2021; 9:249. [PMID: 33530454 PMCID: PMC7912173 DOI: 10.3390/microorganisms9020249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/14/2021] [Accepted: 01/20/2021] [Indexed: 12/16/2022] Open
Abstract
Fuels and polymer precursors are widely used in daily life and in many industrial processes. Although these compounds are mainly derived from petrol, bacteria and yeast can produce them in an environment-friendly way. However, these molecules exhibit toxic solvent properties and reduce cell viability of the microbial producer which inevitably impedes high product titers. Hence, studying how product accumulation affects microbes and understanding how microbial adaptive responses counteract these harmful defects helps to maximize yields. Here, we specifically focus on the mode of toxicity of industry-relevant alcohols, terpenoids and aromatics and the associated stress-response mechanisms, encountered in several relevant bacterial and yeast producers. In practice, integrating heterologous defense mechanisms, overexpressing native stress responses or triggering multiple protection pathways by modifying the transcription machinery or small RNAs (sRNAs) are suitable strategies to improve solvent tolerance. Therefore, tolerance engineering, in combination with metabolic pathway optimization, shows high potential in developing superior microbial producers.
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Affiliation(s)
- Thomas Schalck
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Bram Van den Bergh
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Jan Michiels
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
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New Provisional Function of OmpA from Acinetobacter sp. Strain SA01 Based on Environmental Challenges. mSystems 2021; 6:6/1/e01175-20. [PMID: 33436517 PMCID: PMC7901484 DOI: 10.1128/msystems.01175-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Acinetobacter OmpA is known as a multifaceted protein with multiple functions, including emulsifying properties. Bioemulsifiers are surface-active compounds that can disperse hydrophobic compounds in water and help increase the bioavailability of hydrophobic hydrocarbons to be used by degrading microorganisms. An outer membrane protein A (OmpA) from Acinetobacter sp. strain SA01 was identified and characterized in-depth based on the structural and functional characteristics already known of its homologues. In silico structural studies showed that this protein can be a slow porin, binds to peptidoglycan, and exhibits emulsifying properties. Characterization of the recombinant SA01-OmpA, based on its emulsifying properties, represented its promising potentials in biotechnology. Also, the presence of SA01-OmpA in outer membrane vesicles (OMV) and biofilm showed that this protein, like its homologues in Acinetobacter baumannii, can be secreted into the extracellular environment through OMVs and play a role in the formation of biofilm. After ensuring the correct selection of the protein of interest, the role of oxidative stress induced by cell nutritional parameters (utilization of specific carbon sources) on the expression level of OmpA was carefully studied. For this purpose, the oxidative stress level of SA01 cell cultures in the presence of three nonrelevant carbon sources (sodium acetate, ethanol, and phenol) was examined under each condition. High expression of SA01-OmpA in ethanol- and phenol-fed cells with higher levels of oxidative stress than acetate suggested that oxidative stress could be a substantial factor in the regulation of SA01-OmpA expression. The significant association of SA01-OmpA expression with the levels of oxidative stress induced by cadmium and H2O2, with oxidative stress-inducing properties and lack of nutritional value, confirmed that the cells tend to harness their capacities with a possible increase in OmpA production. Collectively, this study suggests a homeostasis role for OmpA in Acinetobacter sp. SA01 under oxidative stress besides assuming many other roles hitherto attributed to this protein. IMPORTANCEAcinetobacter OmpA is known as a multifaceted protein with multiple functions, including emulsifying properties. Bioemulsifiers are surface-active compounds that can disperse hydrophobic compounds in water and help increase the bioavailability of hydrophobic hydrocarbons to be used by degrading microorganisms. In this study, an OmpA from Acinetobacter sp. SA01 was identified and introduced as an emulsifier with a higher emulsifying capacity than Pseudomonas aeruginosa rhamnolipid. We also showed that the expression of this protein is not dependent on the nutritional requirements but is more influenced by the oxidative stress caused by stressors. This finding, along with the structural role of this protein as a slow porin or its role in OMV biogenesis and biofilm formation, suggests that this protein can play an important role in maintaining cellular homeostasis under oxidative stress conditions. Altogether, the present study provides a new perspective on the functional performance of Acinetobacter OmpA, which can be used both to optimize its production as an emulsifier and a target in the treatment of multidrug-resistant strains.
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Propolis particles incorporated in aqueous formulations with enhanced antibacterial performance. FOOD HYDROCOLLOIDS FOR HEALTH 2021; 1:None. [PMID: 35028635 PMCID: PMC8721958 DOI: 10.1016/j.fhfh.2021.100040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/15/2021] [Accepted: 11/12/2021] [Indexed: 11/20/2022]
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Cao Y, Mu H, Guo J, Liu H, Zhang R, Liu W, Xian M, Liu H. Metabolic engineering of Escherichia coli for the utilization of ethanol. JOURNAL OF BIOLOGICAL RESEARCH (THESSALONIKE, GREECE) 2020; 27:1. [PMID: 31993378 PMCID: PMC6975068 DOI: 10.1186/s40709-020-0111-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/09/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND The fuel ethanol industry has made tremendous progress in the last decades. Ethanol can be obtained by fermentation using a variety of biomass materials as the feedstocks. However, few studies have been conducted on ethanol utilization by microorganisms. The price of petroleum-derived ethanol, easily made by the hydrolysis of ethylene, is even lower than that of bioethanol. If ethanol can be metabolized by microorganisms to produce value-added chemicals, it will open a new door for the utilization of inexpensive ethanol resources. RESULTS We constructed an engineered Escherichia coli strain which could utilize ethanol as the sole carbon source. The alcohol dehydrogenase and aldehyde dehydrogenase from Aspergillus nidulans was introduced into E. coli and the recombinant strain acquired the ability to grow on ethanol. Cell growth continued when ethanol was supplied after glucose starvation and 2.24 g L-1 of ethanol was further consumed during the shake-flasks fermentation process. Then ethanol was further used for the production of mevalonic acid by heterologously expressing its biosynthetic pathway. Deuterium-labeled ethanol-D6 as the feedstock confirmed that mevalonic acid was synthesized from ethanol. CONCLUSIONS This study demonstrated the possibility of using ethanol as the carbon source by engineered E. coli strains. It can serve as the basis for the construction of more robust strains in the future though the catabolic capacity of ethanol should be further improved.
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Affiliation(s)
- Yujin Cao
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Hui Mu
- Energy Research Institute, Shandong Key Laboratory of Biomass Gasification Technology, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Jing Guo
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Hui Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Rubing Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Wei Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Mo Xian
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Huizhou Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
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Yang J, Kim HE, Jung YH, Kim J, Kim DH, Walmsley AR, Kim KH. Zmo0994, a novel LEA-like protein from Zymomonas mobilis, increases multi-abiotic stress tolerance in Escherichia coli. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:151. [PMID: 32863881 PMCID: PMC7448490 DOI: 10.1186/s13068-020-01790-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 08/16/2020] [Indexed: 05/25/2023]
Abstract
BACKGROUND Pretreatment processes and subsequent enzymatic hydrolysis are prerequisites to utilize lignocellulosic sugar for fermentation. However, the resulting hydrolysate frequently hinders fermentation processes due to the presence of inhibitors and toxic products (e.g., ethanol). Thus, it is crucial to develop robust microbes conferring multi-stress tolerance. RESULTS Zmo0994, a functionally uncharacterized protein from Zymomonas mobilis, was identified and characterized for the first time. A major effect of Zmo0994 was a significant enhancement in the tolerance to abiotic stresses such as ethanol, furfural, 5'-hydroxymethylfurfural and high temperature, when expressed in Escherichia coli. Through transcriptome analysis and in vivo experiments, the cellular mechanism of this protein was revealed as due to its ability to trigger genes, involved in aerobic respiration for ATP synthesis. CONCLUSIONS These findings have significant implications that might lead to the development of robust microbes for the highly efficient industrial fermentation processes.
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Affiliation(s)
- Jungwoo Yang
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
| | - Ha Eun Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
| | - Young Hoon Jung
- School of Food Science and Biotechnology, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566 Republic of Korea
| | - Jungyeon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
| | - Do Hyoung Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
| | - Adrian R. Walmsley
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE UK
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
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20
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Liu R, Liang L, Freed EF, Choudhury A, Eckert CA, Gill RT. Engineering regulatory networks for complex phenotypes in E. coli. Nat Commun 2020; 11:4050. [PMID: 32792485 PMCID: PMC7426931 DOI: 10.1038/s41467-020-17721-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/07/2020] [Indexed: 12/11/2022] Open
Abstract
Regulatory networks describe the hierarchical relationship between transcription factors, associated proteins, and their target genes. Regulatory networks respond to environmental and genetic perturbations by reprogramming cellular metabolism. Here we design, construct, and map a comprehensive regulatory network library containing 110,120 specific mutations in 82 regulators expected to perturb metabolism. We screen the library for different targeted phenotypes, and identify mutants that confer strong resistance to various inhibitors, and/or enhanced production of target compounds. These improvements are identified in a single round of selection, showing that the regulatory network library is universally applicable and is convenient and effective for engineering targeted phenotypes. The facile construction and mapping of the regulatory network library provides a path for developing a more detailed understanding of global regulation in E. coli, with potential for adaptation and use in less-understood organisms, expanding toolkits for future strain engineering, synthetic biology, and broader efforts.
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Affiliation(s)
- Rongming Liu
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA
| | - Liya Liang
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA
| | - Emily F Freed
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA
| | - Alaksh Choudhury
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA
| | - Carrie A Eckert
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA.,National Renewable Energy Laboratory (NREL), Golden, Colorado, USA
| | - Ryan T Gill
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado, USA. .,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark.
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21
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Mukherjee N, Mitra S, Adak S, Chakraborty S, Sau A, Goswami A. Evaluation of the growth response of spore forming lactic acid Bacillus–Bacillus coagulans in presence of oxide nanoparticles. APPLIED NANOSCIENCE 2020. [DOI: 10.1007/s13204-020-01512-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Zhou T, Cao H, Zheng J, Teng F, Wang X, Lou K, Zhang X, Tao Y. Suppression of water-bloom cyanobacterium Microcystis aeruginosa by algaecide hydrogen peroxide maximized through programmed cell death. JOURNAL OF HAZARDOUS MATERIALS 2020; 393:122394. [PMID: 32114135 DOI: 10.1016/j.jhazmat.2020.122394] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 02/22/2020] [Accepted: 02/22/2020] [Indexed: 06/10/2023]
Abstract
The global expansion and intensification of toxic cyanobacterial blooms require effective algaecides. Algaecides should be selective, effective, fast-acting, and ideally suppress cyanotoxin production. In this study, whether both maximum growth suppression and minimal toxin production can be simultaneously achieved was tested with a selective algaecide H2O2, through its ability to induce apoptosis-like programmed cell death (AL PCD) in a common bloom species Microcystis aeruginosa. Under doses of 1-15 mg L-1, non-monotonic dose-response suppression of H2O2 on M. aeruginosa were observed, where maximal cell death and minimal microcystin production both occurred at a moderate dose of 10 mg L-1 H2O2. Maximal cell death was indeed achieved through AL PCD, as revealed by integrated biochemical, structural, physiological and transcriptional evidence; transcriptional profile suggested AL PCD was mediated by mazEF and lexA systems. Higher H2O2 doses directly led to necrosis in M. aeruginosa, while lower doses only caused recoverable stress. The integrated data showed the choice between the two modes of cell death is determined by the intracellular energy state under stress. A model was proposed for suppressing M. aeruginosa with AL PCD or necrosis. H2O2 was demonstrated to simultaneously maximize the suppression of both growth and microcystin production through triggering AL PCD.
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Affiliation(s)
- Tingru Zhou
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China; Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Huansheng Cao
- Biodesign Center for Fundamental and Applied Microbiomics, Arizona State University, Tempe, AZ, 85287, USA.
| | - Jie Zheng
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China; Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Tsinghua Shenzhen International Graduate School, Tsinghua University, PR China
| | - Fei Teng
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China; Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Xuejian Wang
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China; Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Kai Lou
- Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Tsinghua Shenzhen International Graduate School, Tsinghua University, PR China
| | - Xihui Zhang
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China
| | - Yi Tao
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China; Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, PR China.
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Liang L, Liu R, Freed EF, Eckert CA. Synthetic Biology and Metabolic Engineering Employing Escherichia coli for C2-C6 Bioalcohol Production. Front Bioeng Biotechnol 2020; 8:710. [PMID: 32719784 PMCID: PMC7347752 DOI: 10.3389/fbioe.2020.00710] [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: 04/22/2020] [Accepted: 06/08/2020] [Indexed: 12/18/2022] Open
Abstract
Biofuel production from renewable and sustainable resources is playing an increasingly important role within the fuel industry. Among biofuels, bioethanol has been most widely used as an additive for gasoline. Higher alcohols can be blended at a higher volume compared to ethanol and generate lower greenhouse gas (GHG) emissions without a need to change current fuel infrastructures. Thus, these fuels have the potential to replace fossil fuels in support of more environmentally friendly processes. This review summarizes the efforts to enhance bioalcohol production in engineered Escherichia coli over the last 5 years and analyzes the current challenges for increasing productivities for industrial applications.
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Affiliation(s)
- Liya Liang
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO, United States
| | - Rongming Liu
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO, United States
| | - Emily F. Freed
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO, United States
| | - Carrie A. Eckert
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO, United States
- National Renewable Energy Laboratory, Golden, CO, United States
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24
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Can ethanol partially or fully replace sulfuric acid in the acid wash step of bioethanol production to fight contamination by Lactobacillus fermentum? BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2020. [DOI: 10.1007/s43153-020-00033-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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25
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Ethanol Decreases Pseudomonas aeruginosa Flagellar Motility through the Regulation of Flagellar Stators. J Bacteriol 2019; 201:JB.00285-19. [PMID: 31109994 DOI: 10.1128/jb.00285-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 05/17/2019] [Indexed: 12/16/2022] Open
Abstract
Pseudomonas aeruginosa frequently encounters microbes that produce ethanol. Low concentrations of ethanol reduced P. aeruginosa swim zone area by up to 45% in soft agar. The reduction of swimming by ethanol required the flagellar motor proteins MotAB and two PilZ domain proteins (FlgZ and PilZ). PilY1 and the type 4 pilus alignment complex (comprising PilMNOP) were previously implicated in MotAB regulation in surface-associated cells and were required for ethanol-dependent motility repression. As FlgZ requires the second messenger bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) to represses motility, we screened mutants lacking genes involved in c-di-GMP metabolism and found that mutants lacking diguanylate cyclases SadC and GcbA were less responsive to ethanol. The double mutant was resistant to its effects. As published previously, ethanol also represses swarming motility, and the same genes required for ethanol effects on swimming motility were required for its regulation of swarming. Microscopic analysis of single cells in soft agar revealed that ethanol effects on swim zone area correlated with ethanol effects on the portion of cells that paused or stopped during the time interval analyzed. Ethanol increased c-di-GMP in planktonic wild-type cells but not in ΔmotAB or ΔsadC ΔgcbA mutants, suggesting c-di-GMP plays a role in the response to ethanol in planktonic cells. We propose that ethanol produced by other microbes induces a regulated decrease in P. aeruginosa motility, thereby promoting P. aeruginosa colocalization with ethanol-producing microbes. Furthermore, some of the same factors involved in the response to surface contact are involved in the response to ethanol.IMPORTANCE Ethanol is an important biologically active molecule produced by many bacteria and fungi. It has also been identified as a potential marker for disease state in cystic fibrosis. In line with previous data showing that ethanol promotes biofilm formation by Pseudomonas aeruginosa, here we report that ethanol reduces swimming motility using some of the same proteins involved in surface sensing. We propose that these data may provide insight into how microbes, via their metabolic byproducts, can influence P. aeruginosa colocalization in the context of infection and in other polymicrobial settings.
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Wang X, Li Q, Sun C, Cai Z, Zheng X, Guo X, Ni X, Zhou W, Guo Y, Zheng P, Chen N, Sun J, Li Y, Ma Y. GREACE-assisted adaptive laboratory evolution in endpoint fermentation broth enhances lysine production by Escherichia coli. Microb Cell Fact 2019; 18:106. [PMID: 31186003 PMCID: PMC6560909 DOI: 10.1186/s12934-019-1153-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Accepted: 06/01/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Late-stage fermentation broth contains high concentrations of target chemicals. Additionally, it contains various cellular metabolites which have leaked from lysed cells, which would exert multifactorial stress to industrial hyperproducers and perturb both cellular metabolism and product formation. Although adaptive laboratory evolution (ALE) has been wildly used to improve stress tolerance of microbial cell factories, single-factor stress condition (i.e. target product or sodium chloride at a high concentration) is currently provided. In order to enhance bacterial stress tolerance to actual industrial production conditions, ALE in late-stage fermentation broth is desired. Genome replication engineering assisted continuous evolution (GREACE) employs mutants of the proofreading element of DNA polymerase complex (DnaQ) to facilitate mutagenesis. Application of GREACE coupled-with selection under stress conditions is expected to accelerate the ALE process. RESULTS In this study, GREACE was first modified by expressing a DnaQ mutant KR5-2 using an arabinose inducible promoter on a temperature-sensitive plasmid, which resulted in timed mutagenesis introduction. Using this method, tolerance of a lysine hyperproducer E. coli MU-1 was improved by enriching mutants in a lysine endpoint fermentation broth. Afterwards, the KR5-2 expressing plasmid was cured to stabilize acquired genotypes. By subsequent fermentation evaluation, a mutant RS3 with significantly improved lysine production capacity was selected. The final titer, yield and total amount of lysine produced by RS3 in a 5-L batch fermentation reached 155.0 ± 1.4 g/L, 0.59 ± 0.02 g lysine/g glucose, and 605.6 ± 23.5 g, with improvements of 14.8%, 9.3%, and 16.7%, respectively. Further metabolomics and genomics analyses, coupled with molecular biology studies revealed that mutations SpeBA302V, AtpBS165N and SecYM145V mainly contributed both to improved cell integrity under stress conditions and enhanced metabolic flux into lysine synthesis. CONCLUSIONS Our present study indicates that improving a lysine hyperproducer by GREACE-assisted ALE in its stressful living environment is efficient and effective. Accordingly, this is a promising method for improving other valuable chemical hyperproducers.
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Affiliation(s)
- Xiaowei Wang
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Qinggang Li
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Cunmin Sun
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Zhen Cai
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiaomei Zheng
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Xuan Guo
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Xiaomeng Ni
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Wenjuan Zhou
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Yanmei Guo
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Ping Zheng
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
| | - Ning Chen
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Jibin Sun
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
| | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yanhe Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
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On a stake-out: Mycobacterial small RNA identification and regulation. Noncoding RNA Res 2019; 4:86-95. [PMID: 32083232 PMCID: PMC7017587 DOI: 10.1016/j.ncrna.2019.05.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/30/2019] [Accepted: 05/12/2019] [Indexed: 12/23/2022] Open
Abstract
Persistence of mycobacteria in the hostile environment of human macrophage is pivotal for its successful pathogenesis. Rapid adaptation to diverse stresses is the key aspect for their survival in the host cells. A range of heterogeneous mechanisms operate in bacteria to retaliate stress conditions. Small RNAs (sRNA) have been implicated in many of those mechanisms in either a single or multiple regulatory networks to post-transcriptionally modulate bacterial gene expression. Although small RNA profiling in mycobacteria by advanced technologies like deep sequencing, tilling microarray etc. have identified hundreds of sRNA, however, a handful of those small RNAs have been unearthed with precise regulatory mechanism. Extensive investigations on sRNA-mediated gene regulations in eubacteria like Escherichia coli revealed the existence of a plethora of distinctive sRNA mechanisms e.g. base pairing, protein sequestration, RNA decoy etc. Increasing studies on mycobacterial sRNA also discovered several eccentric mechanisms where sRNAs act at the posttranscriptional stage to either activate or repress target gene expression that lead to promote mycobacterial survival in stresses. Several intrinsic features like high GC content, absence of any homologue of abundant RNA chaperones, Hfq and ProQ, isolate sRNA mechanisms of mycobacteria from that of other bacteria. An insightful approach has been taken in this review to describe sRNA identification and its regulations in mycobacterial species especially in Mycobacterium tuberculosis.
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Key Words
- Anti-antisense
- Antisense
- Base pairing
- CDS, coding sequence
- Gene regulation by sRNA
- IGR, intergenic region
- ORF, open reading frame
- RBS, Ribosome binding site
- RNAP, RNA polymerase
- SD, Shine Dalgarno sequence
- Small RNAs
- TF, transcription factor
- TIR, translation initiation region
- UTR, untranslated region
- nt, nucleotide
- sRNA, small RNA
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Physiological, Genetic, and Transcriptomic Analysis of Alcohol-Induced Delay of Escherichia coli Death. Appl Environ Microbiol 2019; 85:AEM.02113-18. [PMID: 30389772 DOI: 10.1128/aem.02113-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 10/27/2018] [Indexed: 11/20/2022] Open
Abstract
When Escherichia coli K-12 is inoculated into rich medium in batch culture, cells experience five phases. While the lag and logarithmic phases are mechanistically fairly well defined, the stationary phase, death phase, and long-term stationary phase are less well understood. Here, we characterize a mechanism of delaying death, a phenomenon we call the "alcohol effect," where the addition of small amounts of certain alcohols prolongs stationary phase for at least 10 days longer than in untreated conditions. We show that the stationary phase is extended when ethanol is added above a minimum threshold concentration. Once ethanol levels fall below a threshold concentration, cells enter the death phase. We also show that the effect is conferred by the addition of straight-chain alcohols 1-propanol, 1-butanol, 1-pentanol, and, to a lesser degree, 1-hexanol. However, methanol, isopropanol, 1-heptanol, and 1-octanol do not delay entry into death phase. Though modulated by RpoS, the alcohol effect does not require RpoS activity or the activities of the AdhE or AdhP alcohol dehydrogenases. Further, we show that ethanol is capable of extending the life span of stationary-phase cultures for non-K-12 E. coli strains and that this effect is caused in part by genes of the glycolate degradation pathway. These data suggest a model where ethanol and other shorter 1-alcohols can serve as signaling molecules, perhaps by modulating patterns of gene expression that normally regulate the transition from stationary phase to death phase.IMPORTANCE In one of the most well-studied organisms in the life sciences, Escherichia coli, we still do not fully understand what causes populations to die. This is largely due to the technological difficulties of studying bacterial cell death. This study provides an avenue to studying how and why E. coli populations, and perhaps other microbes, transition from stationary phase to death phase by exploring how ethanol and other alcohols delay the onset of death. Here, we demonstrate that alcohols are acting as signaling molecules to achieve the delay in death phase. This study not only offers a better understanding of a fundamental process but perhaps also provides a gateway to studying the dynamics between ethanol and microbes in the human gastrointestinal tract.
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Šiková M, Janoušková M, Ramaniuk O, Páleníková P, Pospíšil J, Bartl P, Suder A, Pajer P, Kubičková P, Pavliš O, Hradilová M, Vítovská D, Šanderová H, Převorovský M, Hnilicová J, Krásný L. Ms1 RNA increases the amount of RNA polymerase in Mycobacterium smegmatis. Mol Microbiol 2018; 111:354-372. [PMID: 30427073 DOI: 10.1111/mmi.14159] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2018] [Indexed: 01/13/2023]
Abstract
Ms1 is a sRNA recently found in mycobacteria and several other actinobacterial species. Ms1 interacts with the RNA polymerase (RNAP) core devoid of sigma factors, which differs from 6S RNA that binds to RNAP holoenzymes containing the primary sigma factor. Here we show that Ms1 is the most abundant non-rRNA transcript in stationary phase in Mycobacterium smegmatis. The accumulation of Ms1 stems from its high-level synthesis combined with decreased degradation. We identify the Ms1 promoter, PMs1 , and cis-acting elements important for its activity. Furthermore, we demonstrate that PNPase (an RNase) contributes to the differential accumulation of Ms1 during growth. Then, by comparing the transcriptomes of wt and ΔMs1 strains from stationary phase, we reveal that Ms1 affects the intracellular level of RNAP. The absence of Ms1 results in decreased levels of the mRNAs encoding β and β' subunits of RNAP, which is also reflected at the protein level. Thus, the ΔMs1 strain has a smaller pool of RNAPs available when the transcriptional demand increases. This contributes to the inability of the ΔMs1 strain to rapidly react to environmental changes during outgrowth from stationary phase.
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Affiliation(s)
- Michaela Šiková
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Martina Janoušková
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic.,Faculty of Science, Department of Genetics and Microbiology, Charles University, Prague, Czech Republic
| | - Olga Ramaniuk
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Petra Páleníková
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Jiří Pospíšil
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Pavel Bartl
- Faculty of Nuclear Science and Physical Engineering, Department of Nuclear Chemistry, Czech Technical University in Prague, Prague, Czech Republic
| | - Agnieszka Suder
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Pajer
- Military Health Institute, Military Medical Agency, Prague, Czech Republic
| | - Pavla Kubičková
- Military Health Institute, Military Medical Agency, Prague, Czech Republic
| | - Ota Pavliš
- Military Health Institute, Military Medical Agency, Prague, Czech Republic
| | - Miluše Hradilová
- Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Czech Academy of Sciences, Prague, Czech Republic
| | - Dragana Vítovská
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Hana Šanderová
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Převorovský
- Faculty of Science, Department of Cell Biology, Charles University, Prague, Czech Republic
| | - Jarmila Hnilicová
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Libor Krásný
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
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Zheng H, Yu Z, Shu W, Fu X, Zhao X, Yang S, Tan M, Xu J, Liu Y, Song H. Ethanol effects on the overexpression of heterologous catalase in Escherichia coli BL21 (DE3). Appl Microbiol Biotechnol 2018; 103:1441-1453. [PMID: 30498978 DOI: 10.1007/s00253-018-9509-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/01/2018] [Accepted: 11/07/2018] [Indexed: 01/08/2023]
Abstract
A novel method involving ethanol-induced increase in the heterologous recombinant protein expression in E. coli cells was commonly used in recent studies. However, the detailed mechanism of this method is still to be revealed. This work used comparative transcriptomic analysis and numerous experiments to uncover the mechanism of ethanol effects on the expression of heterologous catalase in the recombinant strain E. coli BL21 (pET26b-katA). The key regulatory genes malK and prpD were found to have the most significant effects on the expression of heterologous catalase. Thus, the maltose ABC transporter and carbon metabolism from propanoate metabolism to citrate cycle were found to be the main regulatory pathways activated by ethanol to enhance the synthesis of heterologous proteins. Based on these mechanisms, a universally applicable E. coli expression host strain for improving the expression of heterologous proteins might be constructed.
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Affiliation(s)
- Hongchen Zheng
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Zhenxiao Yu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Wenju Shu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Xiaoping Fu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Xingya Zhao
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Shibin Yang
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Ming Tan
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Jianyong Xu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Yihan Liu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, The College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
| | - Hui Song
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
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31
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Chen X, Ma A, McDermaid A, Zhang H, Liu C, Cao H, Ma Q. RECTA: Regulon Identification Based on Comparative Genomics and Transcriptomics Analysis. Genes (Basel) 2018; 9:genes9060278. [PMID: 29849014 PMCID: PMC6027394 DOI: 10.3390/genes9060278] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 05/19/2018] [Accepted: 05/25/2018] [Indexed: 11/16/2022] Open
Abstract
Regulons, which serve as co-regulated gene groups contributing to the transcriptional regulation of microbial genomes, have the potential to aid in understanding of underlying regulatory mechanisms. In this study, we designed a novel computational pipeline, regulon identification based on comparative genomics and transcriptomics analysis (RECTA), for regulon prediction related to the gene regulatory network under certain conditions. To demonstrate the effectiveness of this tool, we implemented RECTA on Lactococcus lactis MG1363 data to elucidate acid-response regulons. A total of 51 regulons were identified, 14 of which have computational-verified significance. Among these 14 regulons, five of them were computationally predicted to be connected with acid stress response. Validated by literature, 33 genes in Lactococcus lactis MG1363 were found to have orthologous genes which were associated with six regulons. An acid response related regulatory network was constructed, involving two trans-membrane proteins, eight regulons (llrA, llrC, hllA, ccpA, NHP6A, rcfB, regulons #8 and #39), nine functional modules, and 33 genes with orthologous genes known to be associated with acid stress. The predicted response pathways could serve as promising candidates for better acid tolerance engineering in Lactococcus lactis. Our RECTA pipeline provides an effective way to construct a reliable gene regulatory network through regulon elucidation, and has strong application power and can be effectively applied to other bacterial genomes where the elucidation of the transcriptional regulation network is needed.
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Affiliation(s)
- Xin Chen
- Center for Applied Mathematics, Tianjin University, Tianjin 300072, China.
| | - Anjun Ma
- Bioinformatics and Mathematical Biosciences Lab, Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings, SD 57006, USA.
- Department of Mathematics and Statistics, South Dakota State University, Brookings, SD 57006, USA.
| | - Adam McDermaid
- Bioinformatics and Mathematical Biosciences Lab, Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings, SD 57006, USA.
- Department of Mathematics and Statistics, South Dakota State University, Brookings, SD 57006, USA.
| | - Hanyuan Zhang
- College of Computer Science and Engineering, University of Nebraska Lincoln, Lincoln, NE 68588, USA.
| | - Chao Liu
- Shandong Provincial Hospital affiliated to Shandong University, Jinan 250021, China.
| | - Huansheng Cao
- Center for Fundamental and Applied Microbiomics, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.
| | - Qin Ma
- Bioinformatics and Mathematical Biosciences Lab, Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings, SD 57006, USA.
- Department of Mathematics and Statistics, South Dakota State University, Brookings, SD 57006, USA.
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33
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Ye J, Liu J, Li C, Zhou P, Wu S, Ou H. Heterogeneous photocatalysis of tris(2-chloroethyl) phosphate by UV/TiO 2: Degradation products and impacts on bacterial proteome. WATER RESEARCH 2017; 124:29-38. [PMID: 28738271 DOI: 10.1016/j.watres.2017.07.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/27/2017] [Accepted: 07/15/2017] [Indexed: 05/22/2023]
Abstract
The widespread, persistent and toxic organophosphorus esters (OPEs) have become one category of emerging environmental contaminants. Thus, it is in urgent need to develop a cost-effective and safe treatment technology for OPEs control. The current study is a comprehensive attempt to use UV/TiO2 heterogeneous photocatalysis for the degradation of a water dissolved OPEs, tris(2-chloroethyl) phosphate (TCEP). A pseudo-first order degradation reaction with a kobs of 0.3167 min-1 was observed, while hydroxyl radical may be the dominating reactive oxidative species. As the reaction proceeded, TCEP was transformed to a series of hydroxylated and dechlorinated products. The degradation efficiency was significantly affected by pH value, natural organic matters and anions, implying that the complete mineralization of TCEP would be difficult to achieve in actual water treatment process. Based on the proteomics analysis regarding the metabolism reactions, pathways and networks, the significant activation of transmembrane transport and energy generation in Escherichia coli exposed to preliminary degrading products suggested that they can be transported and utilized through cellular metabolism. Furthermore, the descending trend of stress resistance exhibited that the toxicity of products was obviously weakened as the treatment proceeded. In conclusion, hydroxylation and dechlorination of TCEP with incomplete mineralization were likewise effective for its detoxification, indicating that UV/TiO2 will be an alternative treatment method for OPEs control.
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Affiliation(s)
- Jinshao Ye
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China; Joint Genome Institute, Lawrence Berkeley National Laboratory, Walnut Creek 94598, CA, USA
| | - Juan Liu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Chongshu Li
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Pulin Zhou
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Shuang Wu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Huase Ou
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
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