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de Lorenzo V, Pérez-Pantoja D, Nikel PI. Pseudomonas putida KT2440: the long journey of a soil-dweller to become a synthetic biology chassis. J Bacteriol 2024; 206:e0013624. [PMID: 38975763 PMCID: PMC11270871 DOI: 10.1128/jb.00136-24] [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] [Indexed: 07/09/2024] Open
Abstract
Although members of the genus Pseudomonas share specific morphological, metabolic, and genomic traits, the diversity of niches and lifestyles adopted by the family members is vast. One species of the group, Pseudomonas putida, thrives as a colonizer of plant roots and frequently inhabits soils polluted with various types of chemical waste. Owing to a combination of historical contingencies and inherent qualities, a particular strain, P. putida KT2440, emerged time ago as an archetype of an environmental microorganism amenable to recombinant DNA technologies, which was also capable of catabolizing chemical pollutants. Later, the same bacterium progressed as a reliable platform for programming traits and activities in various biotechnological applications. This article summarizes the stepwise upgrading of P. putida KT2440 from being a system for fundamental studies on the biodegradation of aromatic compounds (especially when harboring the TOL plasmid pWW0) to its adoption as a chassis of choice in metabolic engineering and synthetic biology. Although there are remaining uncertainties about the taxonomic classification of KT2440, advanced genome editing capabilities allow us to tailor its genetic makeup to meet specific needs. This makes its traditional categorization somewhat less important, while also increasing the strain's overall value for contemporary industrial and environmental uses.
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Affiliation(s)
- Victor de Lorenzo
- Systems Biology Department, Centro Nacional de Biotecnología (CNB-CSIC), Campus Universidad Autónoma de Madrid, Madrid, Spain
| | - Danilo Pérez-Pantoja
- Instituto Universitario de Investigación y Desarrollo Tecnológico, Universidad Tecnológica Metropolitana (UTEM), Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
| | - Pablo I. Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Systems Environmental Microbiology Group, Kgs. Lyngby, Denmark
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2
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Ujaoney AK, Anaganti N, Padwal MK, Basu B. Tracing the serendipitous genesis of radiation resistance. Mol Microbiol 2024; 121:142-151. [PMID: 38082498 DOI: 10.1111/mmi.15208] [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: 06/05/2023] [Revised: 11/01/2023] [Accepted: 11/27/2023] [Indexed: 01/15/2024]
Abstract
Free-living organisms frequently encounter unfavorable abiotic environmental factors. Those who adapt and cope with sudden changes in the external environment survive. Desiccation is one of the most common and frequently encountered stresses in nature. On the contrary, ionizing radiations are limited to high local concentrations of naturally occurring radioactive materials and related anthropogenic activities. Yet, resistance to high doses of ionizing radiation is evident across the tree of life. The evolution of desiccation resistance has been linked to the evolution of ionizing radiation resistance, although, evidence to support the idea that the evolution of desiccation tolerance is a necessary precursor to ionizing radiation resistance is lacking. Moreover, the presence of radioresistance in hyperthermophiles suggests multiple paths lead to radiation resistance. In this minireview, we focus on the molecular aspects of damage dynamics and damage response pathways comprising protective and restorative functions with a definitive survival advantage, to explore the serendipitous genesis of ionizing radiation resistance.
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Affiliation(s)
- Aman Kumar Ujaoney
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
| | - Narasimha Anaganti
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
| | - Mahesh Kumar Padwal
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
| | - Bhakti Basu
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
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3
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Nikolaev YA, Demkina EV, Ilicheva EA, Kanapatskiy TA, Borzenkov IA, Ivanova AE, Tikhonova EN, Sokolova DS, Ruzhitsky AO, El-Registan GI. Ways of Long-Term Survival of Hydrocarbon-Oxidizing Bacteria in a New Biocomposite Material-Silanol-Humate Gel. Microorganisms 2023; 11:1133. [PMID: 37317107 DOI: 10.3390/microorganisms11051133] [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: 03/30/2023] [Revised: 04/19/2023] [Accepted: 04/22/2023] [Indexed: 06/16/2023] Open
Abstract
Immobilized bacterial cells are presently widely used in the development of bacterial preparations for the bioremediation of contaminated environmental objects. Oil hydrocarbons are among the most abundant pollutants. We have previously described a new biocomposite material containing hydrocarbon-oxidizing bacteria (HOB) embedded in silanol-humate gels (SHG) based on humates and aminopropyltriethoxysilane (APTES); high viable cell titer was maintained in this material for at least 12 months. The goal of the work was to describe the ways of long-term HOB survival in SHG and the relevant morphotypes using the techniques of microbiology, instrumental analytical chemistry and biochemistry, and electron microscopy. Bacteria surviving in SHG were characterized by: (1) capacity for rapid reactivation (growth and hydrocarbon oxidation) in fresh medium; (2) ability to synthesize surface-active compounds, which was not observed in the cultures stored without SHG); (3) elevated stress resistance (ability to grow at high Cu2+ and NaCl concentrations); (4) physiological heterogeneity of the populations, which contained the stationary hypometabolic cells, cystlike anabiotic dormant forms (DF), and ultrasmall cells; (5) occurrence of piles in many cells, which were probably used to exchange genetic material; (6) modification of the phase variants spectrum in the population growing after long-term storage in SHG; and (7) oxidation of ethanol and acetate by HOB populations stored in SHG. The combination of the physiological and cytomorphological properties of the cells surviving in SHG for long periods may indicate a new type of long-term bacterial survival, i.e., in a hypometabolic state.
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Affiliation(s)
- Yury A Nikolaev
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Elena V Demkina
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Ekaterina A Ilicheva
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Timur A Kanapatskiy
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Igor A Borzenkov
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Anna E Ivanova
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Ekaterina N Tikhonova
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Diyana S Sokolova
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Alexander O Ruzhitsky
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
| | - Galina I El-Registan
- The Federal State Institution "Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences" (Research Center of Biotechnology RAS), Leninsky Prospect 14, 119991 Moscow, Russia
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MacLean A, Legendre F, Appanna VD. The tricarboxylic acid (TCA) cycle: a malleable metabolic network to counter cellular stress. Crit Rev Biochem Mol Biol 2023; 58:81-97. [PMID: 37125817 DOI: 10.1080/10409238.2023.2201945] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The tricarboxylic acid (TCA) cycle is a primordial metabolic pathway that is conserved from bacteria to humans. Although this network is often viewed primarily as an energy producing engine fueling ATP synthesis via oxidative phosphorylation, mounting evidence reveals that this metabolic hub orchestrates a wide variety of pivotal biological processes. It plays an important part in combatting cellular stress by modulating NADH/NADPH homeostasis, scavenging ROS (reactive oxygen species), producing ATP by substrate-level phosphorylation, signaling and supplying metabolites to quell a range of cellular disruptions. This review elaborates on how the reprogramming of this network prompted by such abiotic stress as metal toxicity, oxidative tension, nutrient challenge and antibiotic insult is critical for countering these conditions in mostly microbial systems. The cross-talk between the stressors and the participants of TCA cycle that results in changes in metabolite and nucleotide concentrations aimed at combatting the abiotic challenge is presented. The fine-tuning of metabolites mediated by disparate enzymes associated with this metabolic hub is discussed. The modulation of enzymatic activities aimed at generating metabolic moieties dedicated to respond to the cellular perturbation is explained. This ancient metabolic network has to be recognized for its ability to execute a plethora of physiological functions beyond its well-established traditional roles.
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Affiliation(s)
- Alex MacLean
- School of Natural Sciences, Laurentian University, Sudbury, Canada
| | - Felix Legendre
- School of Natural Sciences, Laurentian University, Sudbury, Canada
| | - Vasu D Appanna
- School of Natural Sciences, Laurentian University, Sudbury, Canada
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5
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Anti-virulence activity of dihydrocuminyl aldehyde and nisin against spoilage bacterium Pseudomonas aeruginosa XZ01. Lebensm Wiss Technol 2023. [DOI: 10.1016/j.lwt.2023.114573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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6
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Effect of negative air ionization technology on microbial reduction of food-related microorganisms. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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7
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Yao L, Yin C, Huo F. Small-Molecule Fluorescent Probes for Detecting Several Abnormally Expressed Substances in Tumors. MICROMACHINES 2022; 13:1328. [PMID: 36014250 PMCID: PMC9412406 DOI: 10.3390/mi13081328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/04/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Malignant tumors have always been the biggest problem facing human survival, and a huge number of people die from cancer every year. Therefore, the identification and detection of malignant tumors have far-reaching significance for human survival and development. Some substances are abnormally expressed in tumors, such as cyclooxygenase-2 (COX-2), nitroreductase (NTR), pH, biothiols (GSH, Cys, Hcy), hydrogen sulfide (H2S), hydrogen sulfide (H2O2), hypochlorous acid (HOCl) and NADH. Consequently, it is of great value to diagnose and treat malignant tumors due to the identification and detection of these substances. Compared with traditional tumor detection methods, fluorescence imaging technology has the advantages of an inexpensive cost, fast detection and high sensitivity. Herein, we mainly introduce the research progress of fluorescent probes for identifying and detecting abnormally expressed substances in several tumors.
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Affiliation(s)
- Leilei Yao
- Research Institute of Applied Chemistry, Shanxi University, Taiyuan 030006, China
| | - Caixia Yin
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China
| | - Fangjun Huo
- Research Institute of Applied Chemistry, Shanxi University, Taiyuan 030006, China
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8
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Circella E, Casalino G, Camarda A, Schiavone A, D'Amico F, Dimuccio MM, Pugliese N, Ceci E, Romito D, Bozzo G. <em>Pseudomonas fluorescens</em> group bacteria as responsible for chromatic alteration on rabbit carcasses. Possible hygienic implications. Ital J Food Saf 2022; 11:9998. [PMID: 35795461 PMCID: PMC9251874 DOI: 10.4081/ijfs.2022.9998] [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: 07/23/2021] [Accepted: 02/21/2022] [Indexed: 11/23/2022] Open
Abstract
Bacteria belonging to the genus Pseudomonas are ubiquitous and characterized by a high adaptation capability to different environmental conditions and wide range of temperatures. They may colonize food, sometimes causing alteration. Quite recently, a blue pigmentation due to Pseudomonas fluorescens has been widely reported in mozzarella cheese. In this report, we describe a blue coloration occurred on rabbit meat stored in the refrigeration cell of a slaughterhouse. The alteration was observed after about 72 hours of storage at 4-6°C. Bacteriological analyses were performed, and a microorganism included in the Pseudomonas fluorescens group was identified. The experimental contamination was planned, using a bacterial suspension with 1×108 UFC/ml load to spread on rabbit carcasses. The blue pigmentation appeared after 24 hours of storage in a cell with the same conditions of temperature. The bacterium was reisolated and identified as responsible for the alteration on meat. These findings highlight the importance of considering the members of the genus Pseudomonas and, more specifically, of the P. fluorescens group when the microbiological quality of food is to be ascertained. In fact, even if these bacteria are not considered a public health problem, their presence should be monitored by food industry operators in self-control plans because they may cause alteration in food. In fact, any altered product should be withdrawn from the market in agreement with Regulation (EC) No 178/2002 of the European Parliament and of the Council.
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9
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Leseigneur C, Boucontet L, Duchateau M, Pizarro-Cerda J, Matondo M, Colucci-Guyon E, Dussurget O. NAD kinase promotes Staphylococcus aureus pathogenesis by supporting production of virulence factors and protective enzymes. eLife 2022; 11:79941. [PMID: 35723663 PMCID: PMC9208755 DOI: 10.7554/elife.79941] [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: 05/03/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) is the primary electron donor for reductive reactions that are essential for the biosynthesis of major cell components in all organisms. Nicotinamide adenine dinucleotide kinase (NADK) is the only enzyme that catalyzes the synthesis of NADP(H) from NAD(H). While the enzymatic properties and physiological functions of NADK have been thoroughly studied, the role of NADK in bacterial pathogenesis remains unknown. Here, we used CRISPR interference to knock down NADK gene expression to address the role of this enzyme in Staphylococcus aureus pathogenic potential. We find that NADK inhibition drastically decreases mortality of zebrafish infected with S. aureus. Furthermore, we show that NADK promotes S. aureus survival in infected macrophages by protecting bacteria from antimicrobial defense mechanisms. Proteome-wide data analysis revealed that production of major virulence-associated factors is sustained by NADK. We demonstrate that NADK is required for expression of the quorum-sensing response regulator AgrA, which controls critical S. aureus virulence determinants. These findings support a key role for NADK in bacteria survival within innate immune cells and the host during infection.
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Affiliation(s)
- Clarisse Leseigneur
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Laurent Boucontet
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Magalie Duchateau
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Javier Pizarro-Cerda
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Mariette Matondo
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Emma Colucci-Guyon
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
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10
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The oxidative stress and metabolic response of Acinetobacter baumannii for aPDT multiple photosensitization. Sci Rep 2022; 12:1913. [PMID: 35115588 PMCID: PMC8814140 DOI: 10.1038/s41598-022-05650-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 01/11/2022] [Indexed: 01/10/2023] Open
Abstract
The use of antimicrobial photodynamic inactivation as a non-antibiotic alternative method to inactivate Acinetobacter baumannii was described in response to the ever-growing problem of antibiotic resistance. It was found that irradiation of the bacterial suspension for 10 min reduced the number of viable cells by approximately 99% and this energy fluence was considered to be sub-lethal phototherapy. The lethal dose of laser light (cell mortality about 99.9%) was 9.54 J cm−2, which corresponds to 30 min of irradiation. After a 15-fold phototherapy cycle, the tolerance to aPDT decreased, resulting in a decrease in the number of viable cells by 2.15 and 3.23 log10 CFU/ml units with the use of sub-lethal and lethal light doses, respectively. Multiple photosensitizations decreased the biofilm formation efficiency by 25 ± 1% and 35 ± 1%, respectively. No changes in antibiotic resistance were observed, whereas the cells were more sensitive to hydrogen peroxide. Metabolomic changes after multiple photosensitization were studied and 1H NMR measurements were used in statistical and multivariate data analysis. Many significant changes in the levels of the metabolites were detected demonstrating the response of A. baumannii to oxidative stress.
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11
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MacLean A, Legendre F, Tharmalingam S, Appanna VD. Phosphate stress triggers the conversion of glycerol into l-carnitine in Pseudomonas fluorescens. Microbiol Res 2021; 253:126865. [PMID: 34562839 DOI: 10.1016/j.micres.2021.126865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/26/2021] [Accepted: 09/07/2021] [Indexed: 11/25/2022]
Abstract
Glycerol, a by-product of the biofuel industry is transformed into l-carnitine when the soil microbe Pseudomonas fluorescens is cultured in a phosphate-limited mineral medium (LP). Although the biomass yield was similar to that recorded in phosphate-sufficient cultures (HP), the rate of growth was slower. Phosphate was completely consumed in the LP cultures while in the HP media, approximately 35 % of the initial phosphate was detected at stationary phase of growth. The enhanced production of α-ketoglutarate (KG) in HP cultures supplemented with manganese was recently reported (Alhasawi et al., 2017). l-carnitine appeared to be a prominent metabolite in the spent fluid while the soluble cellular-free extract was characterized with peaks attributable to lysine, γ-butyrobetaine (GB), acetate and succinate in the LP cultures. Upon incubation with glycerol and NH4Cl, the resting cells readily secreted l-carnitine and revealed the presence of such precursors like GB, lysine and methionine involved in the synthesis of this trimethylated moiety. Functional proteomic studies of select enzymes participating in tricarboxylic acid cycle (TCA), oxidative phosphorylation (OP), glyoxylate cycle and l-carnitine synthesis revealed a major metabolic reconfiguration evoked by phosphate stress. While isocitrate dehydrogenase-NAD+ dependent (ICDH-NAD+) and Complex I were markedly diminished, the activities of γ-butyrobetaine aldehyde dehydrogenase (GBADH) and l-carnitine dehydrogenase (CDH) were enhanced. Real-time quantitative polymerase chain reaction (RT-qPCR) analyses pointed to an increase in transcripts of the enzymes γ-butyrobetaine dioxygenase (bbox1), S-adenosylmethionine synthase (metK) and l-carnitine dehydrogenase (lcdH). The l-carnitine/γ-butyrobetaine antiporter (caiT) was enhanced more than 400-fold in the LP cultures compared to the HP controls. This metabolic reprogramming modulated by phosphate deprivation may provide an effective technology to transform glycerol, an industrial waste into valuable l-carnitine.
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Affiliation(s)
- A MacLean
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada
| | - F Legendre
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada
| | - S Tharmalingam
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada; Northern Ontario School of Medicine, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada
| | - V D Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada.
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12
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Liu Y, Yang W, Su T, Che C, Li G, Chen C, Si M. The cssR gene of Corynebacterium glutamicum plays a negative regulatory role in stress responses. Microb Cell Fact 2021; 20:110. [PMID: 34082775 PMCID: PMC8176726 DOI: 10.1186/s12934-021-01600-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 05/25/2021] [Indexed: 12/19/2022] Open
Abstract
Background CssR, the product of the Corynebacterium glutamicum ncgl1578 gene cotranscribed with ncgl1579, is a TetR (tetracycline regulator) family repressor. Although many TetR-type regulators in C. glutamicum have been extensively described, members of the TetR family involved in the stress response remain unidentified. Results In this study, we found that CssR regulated the transcription of its own gene and the ncgl1576-ncgl1577 operon. The ncgl1576-ncgl1577 operon, which is located upstream of cssR in the orientation opposite that of the cssR operon, encodes an ATP-binding cassette (ABC), some of which are involved in the export of a wide range of antimicrobial compounds. The cssR-deletion (ΔcssR) mutant displayed increased resistance to various stresses. An imperfect palindromic motif (5′-TAA(G)TGN13CA(G)TTA-3′; 25 bp) located at the intergenic region between cssR and ncgl1577 was identified as the sole binding site for CssR. Expression of cssR and ncgl1577 was induced by antibiotics and heavy metals but not H2O2 or diamide, and the DNA-binding activity of CssR was impaired by antibiotics and heavy metals but not H2O2. Antibiotics and heavy metals caused CssR dissociation from target gene promoters, thus derepressing their transcription. Oxidant treatment neither altered the conformation of CssR nor modified its cysteine residues, indicating that the cysteine residues in CssR have no redox activity. In the ΔcssR mutant strain, genes involved in redox homeostasis also showed increased transcription levels, and the NADPH/NADP+ ratio was higher than that of the parental strain. Conclusion The stress response mechanism of CssR in C. glutamicum is realized via ligand-induced conformational changes of the protein, not via cysteine oxidation-based thiol modification. Moreover, the crucial role of CssR in the stress response was demonstrated by negatively controlling the expression of the ncgl1576-ncgl1577 operon, its structural gene, and/or redox homeostasis-related genes. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01600-8.
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Affiliation(s)
- Yang Liu
- College of Life Sciences, Qufu Normal University, Qufu, 273165, Shandong, China
| | - Wenzhi Yang
- School of Food Science and Nutrition, University of Leeds, Leeds, LS2 9JT, UK
| | - Tao Su
- College of Life Sciences, Qufu Normal University, Qufu, 273165, Shandong, China
| | - Chengchuan Che
- College of Life Sciences, Qufu Normal University, Qufu, 273165, Shandong, China
| | - Guizhi Li
- College of Life Sciences, Qufu Normal University, Qufu, 273165, Shandong, China
| | - Can Chen
- Key Laboratory of Plant Genetics and Molecular Breeding, Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou, 466001, Henan, China.
| | - Meiru Si
- College of Life Sciences, Qufu Normal University, Qufu, 273165, Shandong, China.
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Reconfiguration of metabolic fluxes in Pseudomonas putida as a response to sub-lethal oxidative stress. THE ISME JOURNAL 2021; 15:1751-1766. [PMID: 33432138 PMCID: PMC8163872 DOI: 10.1038/s41396-020-00884-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 12/14/2020] [Indexed: 01/29/2023]
Abstract
As a frequent inhabitant of sites polluted with toxic chemicals, the soil bacterium and plant-root colonizer Pseudomonas putida can tolerate high levels of endogenous and exogenous oxidative stress. Yet, the ultimate reason of such phenotypic property remains largely unknown. To shed light on this question, metabolic network-wide routes for NADPH generation-the metabolic currency that fuels redox-stress quenching mechanisms-were inspected when P. putida KT2440 was challenged with a sub-lethal H2O2 dose as a proxy of oxidative conditions. 13C-tracer experiments, metabolomics, and flux analysis, together with the assessment of physiological parameters and measurement of enzymatic activities, revealed a substantial flux reconfiguration in oxidative environments. In particular, periplasmic glucose processing was rerouted to cytoplasmic oxidation, and the cyclic operation of the pentose phosphate pathway led to significant NADPH-forming fluxes, exceeding biosynthetic demands by ~50%. The resulting NADPH surplus, in turn, fueled the glutathione system for H2O2 reduction. These properties not only account for the tolerance of P. putida to environmental insults-some of which end up in the formation of reactive oxygen species-but they also highlight the value of this bacterial host as a platform for environmental bioremediation and metabolic engineering.
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14
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Chen X, Wicaksono WA, Berg G, Cernava T. Bacterial communities in the plant phyllosphere harbour distinct responders to a broad-spectrum pesticide. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141799. [PMID: 32889475 DOI: 10.1016/j.scitotenv.2020.141799] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/29/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Pesticide application can be accompanied by harmful non-target effects that affect humans, animals, as well as whole ecosystems. However, such effects remain mainly unaddressed in connection with microorganisms, and especially bacteria therein, which are essential for ecosystem functioning and host health. We analysed bacterial communities by sequencing 16S rRNA gene fragment amplicons following spray application of a broad-spectrum fungicide based on the active ingredient N-(3,5-dichlorophenyl) succinimide on Nicotiana tabacum L. leaves. The plant's phyllosphere was predominantly colonized by Proteobacteria, with Alphaproteobacteria accounting for up to 33.8% of the indigenous bacterial community. Bioinformatic analyses indicated that pesticide applications had an effect on the core microbiome as well as the rare microbiome. Moreover, the interference of the pesticide with phyllosphere bacteria was found to be selective. We have identified four positive responders including an ASV assigned to the genus Acinetobacter and 12 negative responders mainly assigned to bacterial genera known for beneficial plant-microbe interactions, including Stenotrophomonas, Sphingomonas, Flavobacterium and Serratia. Complementary inference of bacterial functioning on community level indicated that microbes with distinct stress response systems were likely enriched in the conducted treatments. The overall findings confirmed that pesticide treatments can induce measureable shifts in non-target bacterial communities colonizing the plant phyllosphere. They also indicate that potentially beneficial bacteria, which are known for their intrinsic association with plants, are among the most sensitive responders to the employed fungicide and thus highlight the importance of off-target studies in the context of the plant microbiome.
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Affiliation(s)
- Xiaoyulong Chen
- Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, 550025 Guiyang, China; College of Tobacco Science, Guizhou University, 550025 Guiyang, China; Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, 550025 Guiyang, China
| | - Wisnu Adi Wicaksono
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria.
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria.
| | - Tomislav Cernava
- College of Tobacco Science, Guizhou University, 550025 Guiyang, China; Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, 550025 Guiyang, China; Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria.
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15
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Metabolic reconstruction of Pseudomonas chlororaphis ATCC 9446 to understand its metabolic potential as a phenazine-1-carboxamide-producing strain. Appl Microbiol Biotechnol 2020; 104:10119-10132. [PMID: 32984920 DOI: 10.1007/s00253-020-10913-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/07/2020] [Accepted: 09/15/2020] [Indexed: 01/01/2023]
Abstract
Pseudomonas chlororaphis is a plant-associated bacterium with reported antagonistic activity against different organisms and plant growth-promoting properties. P. chlororaphis possesses exciting biotechnological features shared with another Pseudomonas with a nonpathogenic phenotype. Part of the antagonistic role of P. chlororaphis is due to its production of a wide variety of phenazines. To expand the knowledge of the metabolic traits of this organism, we constructed the first experimentally validated genome-scale model of P. chlororaphis ATCC 9446, containing 1267 genes and 2289 reactions, and analyzed strategies to maximize its potential for the production of phenazine-1-carboxamide (PCN). The resulting model also describes the capability of P. chlororaphis to carry out the denitrification process and its ability to consume sucrose (Scr), trehalose, mannose, and galactose as carbon sources. Additionally, metabolic network analysis suggested fatty acids as the best carbon source for PCN production. Moreover, the optimization of PCN production was performed with glucose and glycerol. The optimal PCN production phenotype requires an increased carbon flux in TCA and glutamine synthesis. Our simulations highlight the intrinsic H2O2 flux associated with PCN production, which may generate cellular stress in an overproducing strain. These results suggest that an improved antioxidative strategy could lead to optimal performance of phenazine-producing strains of P. chlororaphis. KEY POINTS : • This is the first publication of a metabolic model for a strain of P. chlororaphis. • Genome-scale model is worthy tool to increase the knowledge of a non model organism. • Fluxes simulations indicate a possible effect of H2O2 on phenazines production. • P. chlororaphis can be a suitable model for a wide variety of compounds.
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Systems Analysis of NADH Dehydrogenase Mutants Reveals Flexibility and Limits of Pseudomonas taiwanensis VLB120's Metabolism. Appl Environ Microbiol 2020; 86:AEM.03038-19. [PMID: 32245760 DOI: 10.1128/aem.03038-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Obligate aerobic organisms rely on a functional electron transport chain for energy conservation and NADH oxidation. Because of this essential requirement, the genes of this pathway are likely constitutively and highly expressed to avoid a cofactor imbalance and energy shortage under fluctuating environmental conditions. We here investigated the essentiality of the three NADH dehydrogenases of the respiratory chain of the obligate aerobe Pseudomonas taiwanensis VLB120 and the impact of the knockouts of corresponding genes on its physiology and metabolism. While a mutant lacking all three NADH dehydrogenases seemed to be nonviable, the single or double knockout mutant strains displayed no, or only a weak, phenotype. Only the mutant deficient in both type 2 dehydrogenases showed a clear phenotype with biphasic growth behavior and a strongly reduced growth rate in the second phase. In-depth analyses of the metabolism of the generated mutants, including quantitative physiological experiments, transcript analysis, proteomics, and enzyme activity assays revealed distinct responses to type 2 and type 1 dehydrogenase deletions. An overall high metabolic flexibility enables P. taiwanensis to cope with the introduced genetic perturbations and maintain stable phenotypes, likely by rerouting of metabolic fluxes. This metabolic adaptability has implications for biotechnological applications. While the phenotypic robustness is favorable in large-scale applications with inhomogeneous conditions, the possible versatile redirecting of carbon fluxes upon genetic interventions can thwart metabolic engineering efforts.IMPORTANCE While Pseudomonas has the capability for high metabolic activity and the provision of reduced redox cofactors important for biocatalytic applications, exploitation of this characteristic might be hindered by high, constitutive activity of and, consequently, competition with the NADH dehydrogenases of the respiratory chain. The in-depth analysis of NADH dehydrogenase mutants of Pseudomonas taiwanensis VLB120 presented here provides insight into the phenotypic and metabolic response of this strain to these redox metabolism perturbations. This high degree of metabolic flexibility needs to be taken into account for rational engineering of this promising biotechnological workhorse toward a host with a controlled and efficient supply of redox cofactors for product synthesis.
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MacLean A, Bley AM, Appanna VP, Appanna VD. Metabolic manipulation by Pseudomonas fluorescens: a powerful stratagem against oxidative and metal stress. J Med Microbiol 2020; 69:339-346. [PMID: 31961786 DOI: 10.1099/jmm.0.001139] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Metabolism is the foundation of all living organisms and is at the core of numerous if not all biological processes. The ability of an organism to modulate its metabolism is a central characteristic needed to proliferate, to be dormant and to survive any assault. Pseudomonas fluorescens is bestowed with a uniquely versatile metabolic framework that enables the microbe to adapt to a wide range of conditions including disparate nutrients and toxins. In this mini-review we elaborate on the various metabolic reconfigurations evoked by this microbial system to combat reactive oxygen/nitrogen species and metal stress. The fine-tuning of the NADH/NADPH homeostasis coupled with the production of α-keto-acids and ATP allows for the maintenance of a reductive intracellular milieu. The metabolic networks propelling the synthesis of metabolites like oxalate and aspartate are critical to keep toxic metals at bay. The biochemical processes resulting from these defensive mechanisms provide molecular clues to thwart infectious microbes and reveal elegant pathways to generate value-added products.
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Affiliation(s)
- Alex MacLean
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Anondo Michel Bley
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Varun P Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Vasu D Appanna
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
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18
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Wang X, Li BB, Ma TT, Sun LY, Tai L, Hu CH, Liu WT, Li WQ, Chen KM. The NAD kinase OsNADK1 affects the intracellular redox balance and enhances the tolerance of rice to drought. BMC PLANT BIOLOGY 2020; 20:11. [PMID: 31910821 PMCID: PMC6947874 DOI: 10.1186/s12870-019-2234-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 12/30/2019] [Indexed: 05/04/2023]
Abstract
BACKGROUND NAD kinases (NADKs) are the only known enzymes that directly phosphorylate NAD(H) to generate NADP(H) in different subcellular compartments. They participate in multiple life activities, such as modulating the NADP/NAD ratio, maintaining the intracellular redox balance and responding to environmental stresses. However, the functions of individual NADK in plants are still under investigation. Here, a rice NADK, namely, OsNADK1, was identified, and its functions in plant growth regulation and stress tolerance were analysed by employing a series of transgenic plant lines. RESULTS OsNADK1 is a cytosol-localized NADK in rice. It was expressed in all rice tissues examined, and its transcriptional expression could be stimulated by a number of environmental stress treatments. Compared with wild-type (WT) rice, the mutant plant osnadk1 in which OsNADK1 was knocked out was a dwarf at the heading stage and had decreased NADP(H)/NAD(H), ascorbic acid (ASA)/dehydroascorbate (DHA) and reduced glutathione (GSH)/oxidized glutathione (GSSG) ratios, which led to increased oxidation states in the rice cells and sensitivity to drought. Moreover, certain stress-related genes showed differential expression patterns in osnadk1 under both normal growth and drought-stress conditions compared with WT. Among these genes, OsDREB1B and several WRKY family transcription factors, e.g., OsWRKY21 and OsWRKY42, showed correlated co-expression patterns with OsNADK1 in osnadk1 and the plants overexpressing or underexpressing OsNADK1, implying roles for these transcription factors in OsNADK1-mediated processes. In addition, overexpression of OsNADK1 enhanced the drought tolerance of rice plants, whereas loss of function of the gene reduced the tolerance. Furthermore, the proline content was dramatically increased in the leaves of the OsNADK1-overexpressing lines under drought conditions. CONCLUSIONS Altogether, the results suggest that an OsNADK1-mediated intracellular redox balance is involved in the tolerance of rice plants to drought.
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Affiliation(s)
- Xiang Wang
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074 Hubei China
| | - Bin-Bin Li
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Tian-Tian Ma
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Liang-Yu Sun
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Li Tai
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Chun-Hong Hu
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
- College of Life Science and Agriculture, Zhoukou Normal University, Zhoukou, 466001 Henan China
| | - Wen-Ting Liu
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Wen-Qiang Li
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Kun-Ming Chen
- State Key Laboratory of Crop Stress Biology in Arid Area/College of Life Sciences, Northwest A&F University, Yangling, 712100 Shaanxi China
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Modifications of the Aerobic Respiratory Chain of Paracoccus Denitrificans in Response to Superoxide Oxidative Stress. Microorganisms 2019; 7:microorganisms7120640. [PMID: 31816877 PMCID: PMC6955949 DOI: 10.3390/microorganisms7120640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 11/28/2019] [Accepted: 11/29/2019] [Indexed: 11/17/2022] Open
Abstract
Paracoccus denitrificans is a strictly respiring bacterium with a core respiratory chain similar to that of mammalian mitochondria. As such, it continuously produces and has to cope with superoxide and other reactive oxygen species. In this work, the effects of artificially imposed superoxide stress on electron transport were examined. Exposure of aerobically growing cells to paraquat resulted in decreased activities of NADH dehydrogenase, succinate dehydrogenase, and N,N,N’,N’-tetramethyl-p-phenylenediamine (TMPD) oxidase. Concomitantly, the total NAD(H) pool size in cells was approximately halved, but the NADH/NAD+ ratio increased twofold, thus partly compensating for inactivation losses of the dehydrogenase. The inactivation of respiratory dehydrogenases, but not of TMPD oxidase, also took place upon treatment of the membrane fraction with xanthine/xanthine oxidase. The decrease in dehydrogenase activities could be fully rescued by anaerobic incubation of membranes in a mixture containing 2-mercaptoethanol, sulfide and ferrous iron, which suggests iron–sulfur clusters as targets for superoxide. By using cyanide titration, a stress-sensitive contribution to the total TMPD oxidase activity was identified and attributed to the cbb3-type terminal oxidase. This response (measured by both enzymatic activity and mRNA level) was abolished in a mutant defective for the FnrP transcription factor. Therefore, our results provide evidence of oxidative stress perception by FnrP.
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20
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Liu Z, Zhao L, Zhang Q, Huo N, Shi X, Li L, Jia L, Lu Y, Peng Y, Song Y. Proteomics-Based Mechanistic Investigation of Escherichia coli Inactivation by Pulsed Electric Field. Front Microbiol 2019; 10:2644. [PMID: 31781086 PMCID: PMC6857472 DOI: 10.3389/fmicb.2019.02644] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/30/2019] [Indexed: 11/21/2022] Open
Abstract
The pulsed electric field (PEF) technology has been widely applied to inactivate pathogenic bacteria in food products. Though irreversible pore formation and membrane disruption is considered to be the main contributing factor to PEF's sterilizing effects, the exact molecular mechanisms remain poorly understood. In this study, by using mass spectrometry (MS)-based label-free quantitative proteomic analysis, we compared the protein profiles of PEF-treated and untreated Escherichia coli. We identified a total of 175 differentially expressed proteins, including 52 candidates that were only detected in at least two of the three samples in one experiment group but not in the other group. Functional analysis revealed that the differential proteins were primarily involved in the regulation of cell membrane composition and integrity, stress response, as well as various metabolic processes. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis was conducted on the genes of selected differential proteins at varying PEF intensities, which were known to result in different cell killing levels. The qRT-PCR data confirmed that the proteomic results could be reliably used for further data interpretation, and that the changes in the expression levels of the differential candidates were, to a large extent, caused directly by the PEF treatment. The findings of the current study offered valuable insight into PEF-induced cell inactivation.
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Affiliation(s)
- Zhenyu Liu
- Information Science and Engineering College, Shanxi Agricultural University, Jinzhong, China
| | - Lingying Zhao
- Department of Food, Agricultural and Biological Engineering, The Ohio State University, Columbus, OH, United States
| | - Qin Zhang
- Life Science College, Shanxi Agricultural University, Jinzhong, China
| | - Nan Huo
- Life Science College, Shanxi Agricultural University, Jinzhong, China
| | - Xiaojing Shi
- Life Science College, Shanxi Agricultural University, Jinzhong, China
| | - Linwei Li
- Information Science and Engineering College, Shanxi Agricultural University, Jinzhong, China
| | - Liyan Jia
- College of Food Science and Engineering, Shanxi Agricultural University, Jinzhong, China
| | - Yuanyuan Lu
- Life Science College, Shanxi Agricultural University, Jinzhong, China
| | - Yong Peng
- Shanghai Applied Protein Technology Co., Ltd., Shanghai, China
| | - Yanbo Song
- Life Science College, Shanxi Agricultural University, Jinzhong, China
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21
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Chuanboon K, Na Nakorn P, Pannengpetch S, Laengsri V, Nuchnoi P, Isarankura-Na-Ayudhya C, Isarankura-Na-Ayudhya P. Proteomics and bioinformatics analysis reveal potential roles of cadmium-binding proteins in cadmium tolerance and accumulation of Enterobacter cloacae. PeerJ 2019; 7:e6904. [PMID: 31534833 PMCID: PMC6727835 DOI: 10.7717/peerj.6904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/03/2019] [Indexed: 01/01/2023] Open
Abstract
Background Enterobacter cloacae (EC) is a Gram-negative bacterium that has been utilized extensively in biotechnological and environmental science applications, possibly because of its high capability for adapting itself and surviving in hazardous conditions. A search for the EC from agricultural and industrial areas that possesses high capability to tolerate and/or accumulate cadmium ions has been conducted in this study. Plausible mechanisms of cellular adaptations in the presence of toxic cadmium have also been proposed. Methods Nine strains of EC were isolated and subsequently identified by biochemical characterization and MALDI-Biotyper. Minimum inhibitory concentrations (MICs) against cadmium, zinc and copper ions were determined by agar dilution method. Growth tolerance against cadmium ions was spectrophotometrically monitored at 600 nm. Cadmium accumulation at both cellular and protein levels was investigated using atomic absorption spectrophotometer. Proteomics analysis by 2D-DIGE in conjunction with protein identification by QTOF-LC-MS/MS was used to study differentially expressed proteins between the tolerant and intolerant strains as consequences of cadmium exposure. Expression of such proteins was confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Bioinformatics tools were applied to propose the functional roles of cadmium-binding protein and its association in cadmium tolerance mechanisms. Results The cadmium-tolerant strain (EC01) and intolerant strain (EC07) with the MICs of 1.6 and 0.4 mM, respectively, were isolated. The whole cell lysate of EC01 exhibited approximately two-fold higher in cadmium binding capability than those of the EC07 and ATCC 13047, possibly by the expression of Cd-binding proteins. Our proteomics analysis revealed the higher expression of DUF326-like domain (a high cysteine-rich protein) of up to 220 fold in the EC01 than that of the EC07. Confirmation of the transcription level of this gene by qRT-PCR revealed a 14-fold induction in the EC01. Regulation of the DUF326-like domain in EC01 was more pronounced to mediate rapid cadmium accumulation (in 6 h) and tolerance than the other resistance mechanisms found in the ATCC 13047 and the EC07 strains. The only one major responsive protein against toxic cadmium found in these three strains belonged to an antioxidative enzyme, namely catalase. The unique proteins found in the ATCC 13047 and EC07 were identified as two groups: (i) ATP synthase subunit alpha, putative hydrolase and superoxide dismutase and (ii) OmpX, protein YciF, OmpC porin, DNA protection during starvation protein, and TrpR binding protein WrbA, respectively. Conclusion All these findings gain insights not only into the molecular mechanisms of cadmium tolerance in EC but also open up a high feasibility to apply the newly discovered DUF326-like domain as cadmium biosorbents for environmental remediation in the future.
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Affiliation(s)
- Kitipong Chuanboon
- Department of Medical Technology and Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand.,Center for Research and Innovation, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Piyada Na Nakorn
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Supitcha Pannengpetch
- Center for Research and Innovation, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Vishuda Laengsri
- Center for Research and Innovation, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Pornlada Nuchnoi
- Center for Research and Innovation, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | | | - Patcharee Isarankura-Na-Ayudhya
- Department of Medical Technology and Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
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Metabolic modulations of Pseudomonas graminis in response to H 2O 2 in cloud water. Sci Rep 2019; 9:12799. [PMID: 31488860 PMCID: PMC6728378 DOI: 10.1038/s41598-019-49319-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/26/2019] [Indexed: 12/26/2022] Open
Abstract
In cloud water, microorganisms are exposed to very strong stresses especially related to the presence of reactive oxygen species including H2O2 and radicals, which are the driving force of cloud chemistry. In order to understand how the bacterium Pseudomonas graminis isolated from cloud water respond to this oxidative stress, it was incubated in microcosms containing a synthetic solution of cloud water in the presence or in the absence of H2O2. P. graminis metabolome was examined by LC-MS and NMR after 50 min and after 24 hours of incubation. After 50 min, the cells were metabolizing H2O2 while this compound was still present in the medium, and it was completely biodegraded after 24 hours. Cells exposed to H2O2 had a distinct metabolome as compared to unexposed cells, revealing modulations of certain metabolic pathways in response to oxidative stress. These data indicated that the regulations observed mainly involved carbohydrate, glutathione, energy, lipid, peptides and amino-acids metabolisms. When cells had detoxified H2O2 from the medium, their metabolome was not distinguishable anymore from unexposed cells, highlighting the capacity of resilience of this bacterium. This work illustrates the interactions existing between the cloud microbial metabolome and cloud chemistry.
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23
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Shimizu K, Matsuoka Y. Redox rebalance against genetic perturbations and modulation of central carbon metabolism by the oxidative stress regulation. Biotechnol Adv 2019; 37:107441. [PMID: 31472206 DOI: 10.1016/j.biotechadv.2019.107441] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 08/04/2019] [Accepted: 08/23/2019] [Indexed: 12/11/2022]
Abstract
The micro-aerophilic organisms and aerobes as well as yeast and higher organisms have evolved to gain energy through respiration (via oxidative phosphorylation), thereby enabling them to grow much faster than anaerobes. However, during respiration, reactive oxygen species (ROSs) are inherently (inevitably) generated, and threaten the cell's survival. Therefore, living organisms (or cells) must furnish the potent defense systems to keep such ROSs at harmless level, where the cofactor balance plays crucial roles. Namely, NADH is the source of energy generation (catabolism) in the respiratory chain reactions, through which ROSs are generated, while NADPH plays important roles not only for the cell synthesis (anabolism) but also for detoxifying ROSs. Therefore, the cell must rebalance the redox ratio by modulating the fluxes of the central carbon metabolism (CCM) by regulating the multi-level regulation machinery upon genetic perturbations and the change in the growth conditions. Here, we discuss about how aerobes accomplish such cofactor homeostasis against redox perturbations. In particular, we consider how single-gene mutants (including pgi, pfk, zwf, gnd and pyk mutants) modulate their metabolisms in relation to cofactor rebalance (and also by adaptive laboratory evolution). We also discuss about how the overproduction of NADPH (by the pathway gene mutation) can be utilized for the efficient production of useful value-added chemicals such as medicinal compounds, polyhydroxyalkanoates, and amino acids, all of which require NADPH in their synthetic pathways. We then discuss about the metabolic responses against oxidative stress, where αketoacids play important roles not only for the coordination between catabolism and anabolism, but also for detoxifying ROSs by non-enzymatic reactions, as well as for reducing the production of ROSs by repressing the activities of the TCA cycle and respiration (via carbon catabolite repression). Thus, we discuss about the mechanisms (basic strategies) that modulate the metabolism from respiration to respiro-fermentative metabolism causing overflow, based on the role of Pyk activity, affecting the NADPH production at the oxidative pentose phosphate (PP) pathway, and the roles of αketoacids for the change in the source of energy generation from the oxidative phosphorylation to the substrate level phosphorylation.
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Affiliation(s)
- Kazuyuki Shimizu
- Kyushu institute of Technology, Iizuka, Fukuoka 820-8502, Japan; Institute of Advanced Biosciences, Keio university, Tsuruoka, Yamagata 997-0017, Japan.
| | - Yu Matsuoka
- Kyushu institute of Technology, Iizuka, Fukuoka 820-8502, Japan.
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The osnR gene of Corynebacterium glutamicum plays a negative regulatory role in oxidative stress responses. ACTA ACUST UNITED AC 2019; 46:241-248. [DOI: 10.1007/s10295-018-02126-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 12/20/2018] [Indexed: 11/26/2022]
Abstract
Abstract
Among the Corynebacterium glutamicum ORFs that have been implicated in stress responses, we chose ORF cg3230, designated osnR, and analyzed it further. Unlike the osnR-deleted strain (ΔosnR), the osnR-overexpressing strain (P180-osnR) developed growth defects and increased sensitivity to various oxidants including H2O2. Transcription in the P180-osnR strain of genes such as sodA (superoxide dismutase), ftn (ferritin biosynthesis), and ahpD (alkyl hydroperoxide reductase; cg2674), which are involved in the detoxification of reactive oxygen species, was only 40% that of the wild type. However, transcription of katA, encoding H2O2-detoxifying catalase, was unchanged in this strain. Genes such as trxB (thioredoxin reductase) and mtr (mycothiol disulfide reductase), which play roles in redox homeostasis, also showed decreased transcription in the strain. 2D-PAGE analysis indicated that genes involved in redox reactions were considerably affected by osnR overexpression. The NADPH/NADP+ ratio of the P180-osnR strain (1.35) was higher than that of the wild-type stain (0.78). Collectively, the phenotypes of the ΔosnR and P180-osnR strains suggest a global regulatory role as well as a negative role for the gene in stress responses, particularly in katA-independent oxidative stress responses.
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25
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Zerfaß C, Asally M, Soyer OS. Interrogating metabolism as an electron flow system. CURRENT OPINION IN SYSTEMS BIOLOGY 2019; 13:59-67. [PMID: 31008413 PMCID: PMC6472609 DOI: 10.1016/j.coisb.2018.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Metabolism is generally considered as a neatly organised system of modular pathways, shaped by evolution under selection for optimal cellular growth. This view falls short of explaining and predicting a number of key observations about the structure and dynamics of metabolism. We highlight these limitations of a pathway-centric view on metabolism and summarise studies suggesting how these could be overcome by viewing metabolism as a thermodynamically and kinetically constrained, dynamical flow system. Such a systems-level, first-principles based view of metabolism can open up new avenues of metabolic engineering and cures for metabolic diseases and allow better insights to a myriad of physiological processes that are ultimately linked to metabolism. Towards further developing this view, we call for a closer interaction among physical and biological disciplines and an increased use of electrochemical and biophysical approaches to interrogate cellular metabolism together with the microenvironment in which it exists.
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Affiliation(s)
- Christian Zerfaß
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Munehiro Asally
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, CV4 7AL, UK
| | - Orkun S. Soyer
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, CV4 7AL, UK
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Prajapati D, Kumari N, Dave K, Chatupale V, Pohnerkar J. Chromomycin, an antibiotic produced by Streptomyces flaviscleroticus might play a role in the resistance to oxidative stress and is essential for viability in stationary phase. Environ Microbiol 2019; 21:814-826. [PMID: 30585380 DOI: 10.1111/1462-2920.14515] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/13/2018] [Accepted: 12/20/2018] [Indexed: 12/14/2022]
Abstract
The well-known role of antibiotics in killing sensitive organisms has been challenged by the effects they exert at subinhibitory concentrations. Unfortunately, there are very few published reports on the advantages these molecules may confer to their producers. This study describes the construction of a genetically verified deletion mutant of Streptomyces flaviscleroticus unable to synthesize chromomycin. This mutant was characterized by a rapid loss of viability in stationary phase that was correlated with high oxidative stress and altered antioxidant defences. Altered levels of key metabolites in the mutant signalled a redistribution of the glycolytic flux toward the PPP to generate NADPH to fight oxidative stress as well as reduction of ATP-phosphofructokinase and Krebs cycle enzymes activities. These changes were correlated with a shift in the preference for carbon utilization from glucose to amino acids. Remarkably, chromomycin at subinhibitory concentration increased longevity of the non-producer and restored most of the phenotypic features' characteristic of the wild type strain. Altogether these observations suggest that chromomycin may have antioxidant properties that would explain, at least in part, some of the phenotypes of the mutant. Our observations warrant reconsideration of the secondary metabolite definition and raise the possibility of crucial roles for their producers.
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Affiliation(s)
- Divya Prajapati
- Department of Bio-Chemistry, The Maharaja Sayajirao University of Baroda, Baroda, 390003, Gujarat, India
| | - Namita Kumari
- Center for Sickle Cell Disease, Howard University, Washington, DC, 20059
| | - Keyur Dave
- Cellcys Labs Pvt. Ltd., Mumbai, 400104, India
| | - Vaidehi Chatupale
- Department of Bio-Chemistry, The Maharaja Sayajirao University of Baroda, Baroda, 390003, Gujarat, India
| | - Jayashree Pohnerkar
- Department of Bio-Chemistry, The Maharaja Sayajirao University of Baroda, Baroda, 390003, Gujarat, India
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ROSA ENDAH, MARDHIAH BATUBARA UMMI, SUPARJO SUPARJO. Chemotactic Motility and Growth of Pseudomonas fluorescens Towards Glucose Concentration. MICROBIOLOGY INDONESIA 2019. [DOI: 10.5454/mi.13.2.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Corona F, Martínez JL, Nikel PI. The global regulator Crc orchestrates the metabolic robustness underlying oxidative stress resistance in Pseudomonas aeruginosa. Environ Microbiol 2018; 21:898-912. [PMID: 30411469 DOI: 10.1111/1462-2920.14471] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 11/01/2018] [Accepted: 11/03/2018] [Indexed: 11/26/2022]
Abstract
The remarkable metabolic versatility of bacteria of the genus Pseudomonas enable their survival across very diverse environmental conditions. P. aeruginosa, one of the most relevant opportunistic pathogens, is a prime example of this adaptability. The interplay between regulatory networks that mediate these metabolic and physiological features is just starting to be explored in detail. Carbon catabolite repression, governed by the Crc protein, controls the availability of several enzymes and transporters involved in the assimilation of secondary carbon sources. Yet, the regulation exerted by Crc on redox metabolism of P. aeruginosa (hence, on the overall physiology) had hitherto been unexplored. In this study, we address the intimate connection between carbon catabolite repression and metabolic robustness of P. aeruginosa PAO1. In particular, we explored the interplay between oxidative stress, metabolic rearrangements in central carbon metabolism and the cellular redox state. By adopting a combination of quantitative physiology experiments, multiomic analyses, transcriptional patterns of key genes, measurement of metabolic activities in vitro and direct quantification of redox balances both in the wild-type strain and in an isogenic Δcrc derivative, we demonstrate that Crc orchestrates the overall response of P. aeruginosa to oxidative stress via reshaping of the core metabolic architecture in this bacterium.
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Affiliation(s)
- Fernando Corona
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología (CNB-CSIC), 28049 Madrid, Spain
| | - José Luis Martínez
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología (CNB-CSIC), 28049 Madrid, Spain
| | - Pablo I Nikel
- Systems Environmental Microbiology Group, The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Kgs Lyngby, Denmark
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Goldbeck O, Eck AW, Seibold GM. Real Time Monitoring of NADPH Concentrations in Corynebacterium glutamicum and Escherichia coli via the Genetically Encoded Sensor mBFP. Front Microbiol 2018; 9:2564. [PMID: 30405597 PMCID: PMC6207642 DOI: 10.3389/fmicb.2018.02564] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 10/08/2018] [Indexed: 12/16/2022] Open
Abstract
Analyses of intracellular NADPH concentrations are prerequisites for the design of microbial production strains and process optimization. mBFP was described as metagenomics derived, blue fluorescent protein showing NADPH-dependent fluorescence. Characterization of mBFP showed a high specificity for binding of NADPH (KD 0.64 mM) and no binding of NADH, the protein exclusively amplified fluorescence of NADPH. mBFP catalyzed the NADPH-dependent reduction of benzaldehyde and further aldehydes, which fits to its classification as short chain dehydrogenase. For in vivo NADPH analyses a codon-optimized gene for mBFP was introduced into Corynebacterium glutamicum WT and the phosphoglucoisomerase-deficient strain C. glutamicum Δpgi, which accumulates high levels of NADPH. For determination of intracellular NADPH concentrations by mBFP a calibration method with permeabilized cells was developed. By this means an increase of intracellular NADPH concentrations within seconds after the addition of glucose to nutrient-starved cells of both C. glutamicum WT and C. glutamicum Δpgi was observed; as expected the internal NADPH concentration was significantly higher for C. glutamicum Δpgi (0.31 mM) when compared to C. glutamicum WT (0.19 mM). Addition of paraquat to E. coli cells carrying mBFP led as expected to an immediate decrease of intracellular NADPH concentrations, showing the versatile use of mBFP as intracellular sensor.
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Affiliation(s)
- Oliver Goldbeck
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany
| | - Alexander W Eck
- Institute for Biochemistry, University of Cologne, Cologne, Germany
| | - Gerd M Seibold
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany.,Institute for Biochemistry, University of Cologne, Cologne, Germany
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Abstract
Oxidation of aromatic compounds can be mutagenic due to the accumulation of reactive oxygen species (ROS) in bacterial cells and thereby facilitate evolution of corresponding catabolic pathways. To examine the effect of the background biochemical network on the evolvability of environmental bacteria hosting a new catabolic pathway, Akkaya and colleagues (mBio 9:e01512-18, 2018, https://doi.org/10.1128/mBio.01512-18) introduced the still-evolving 2,4-dinitrotoluene (2,4-DNT) pathway genes from the original environmental Burkholderia sp. Oxidation of aromatic compounds can be mutagenic due to the accumulation of reactive oxygen species (ROS) in bacterial cells and thereby facilitate evolution of corresponding catabolic pathways. To examine the effect of the background biochemical network on the evolvability of environmental bacteria hosting a new catabolic pathway, Akkaya and colleagues (mBio 9:e01512-18, 2018, https://doi.org/10.1128/mBio.01512-18) introduced the still-evolving 2,4-dinitrotoluene (2,4-DNT) pathway genes from the original environmental Burkholderia sp. isolate into the genome of Pseudomonas putida KT2440. They show that the mutagenic effect of 2,4-DNT oxidation, which is associated with the accumulation of ROS and oxidative damage on DNA, can be avoided by preserving high NADPH levels in P. putida. The observations of this study highlight the impact of the cellular redox status of bacteria on the evolvability of new metabolic pathways.
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31
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Barthen R, Karimzadeh L, Gründig M, Grenzer J, Lippold H, Franke K, Lippmann-Pipke J. Glutamic acid leaching of synthetic covellite - A model system combining experimental data and geochemical modeling. CHEMOSPHERE 2018; 196:368-376. [PMID: 29316462 DOI: 10.1016/j.chemosphere.2017.12.138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 12/19/2017] [Accepted: 12/22/2017] [Indexed: 06/07/2023]
Abstract
For Kupferschiefer mining established pyrometallurgical and acidic bioleaching methods face numerous problems. This is due to the finely grained and dispersed distribution of the copper minerals, the complex mineralogy, comparably low copper content, and the possibly high carbonate and organic content in this ore. Leaching at neutral pH seemed worth a try: At neutral pH the abundant carbonates do not need to be dissolved and therewith would not consume excessive amounts of provided acids. Certainly, copper solubility at neutral pH is reduced compared to an acidic environment; however, if copper complexing ligands would be supplied abundantly, copper contents in the mobile phase could easily reach the required economic level. We set up a model system to study the effect of parameters such as pH, microorganisms, microbial metabolites, and organic ligands on covellite leaching to get a better understanding of the processes in copper leaching at pH ≥ 6. With this model system we could show that glutamic acid and the microbial siderophore desferrioxamine B promote covellite dissolution. Both experimental and modeling data showed that pH is an important parameter in covellite dissolution. An increase of pH from 6 to 9 could elevate copper extraction in the presence of glutamic acid by a factor of five. These results have implications for both development of a biotechnological process regarding metal extraction from Kupferschiefer, and for the interaction of bacterial metabolites with the lithosphere and potential mobilization of heavy metals in alkaline environments.
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Affiliation(s)
- R Barthen
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Dresden, Germany
| | - L Karimzadeh
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Leipzig, Germany
| | - M Gründig
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Leipzig, Germany
| | - J Grenzer
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Dresden, Germany
| | - H Lippold
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Leipzig, Germany.
| | - K Franke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Leipzig, Germany
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Izrael-Živković L, Rikalović M, Gojgić-Cvijović G, Kazazić S, Vrvić M, Brčeski I, Beškoski V, Lončarević B, Gopčević K, Karadžić I. Cadmium specific proteomic responses of a highly resistantPseudomonas aeruginosasan ai. RSC Adv 2018; 8:10549-10560. [PMID: 35540485 PMCID: PMC9078880 DOI: 10.1039/c8ra00371h] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/07/2018] [Indexed: 11/29/2022] Open
Abstract
Pseudomonas aeruginosa san ai is a promising candidate for bioremediation of cadmium pollution, as it resists a high concentration of up to 7.2 mM of cadmium. Leaving biomass of P. aeruginosa san ai exposed to cadmium has a large biosorption potential, implying its capacity to extract heavy metal from contaminated medium. In the present study, we investigated tolerance and accumulation of cadmium on protein level by shotgun proteomics approach based on liquid chromatography and tandem mass spectrometry coupled with bioinformatics to identify proteins. Size exclusion chromatography was used for protein prefractionation to preserve native forms of metalloproteins and protein complexes. Using this approach a total of 60 proteins were observed as up-regulated in cadmium-amended culture. Almost a third of the total numbers of up-regulated were metalloproteins. Particularly interesting are denitrification proteins which are over expressed but not active, suggesting their protective role in conditions of heavy metal exposure. P. aeruginosa san ai developed a complex mechanism to adapt to cadmium, based on: extracellular biosorption, bioaccumulation, the formation of biofilm, controlled siderophore production, enhanced respiration and modified protein profile. An increased abundance of proteins involved in: cell energy metabolism, including denitrification proteins; amino acid metabolism; cell motility and posttranslational modifications, primarily based on thiol-disulfide exchange, were observed. Enhanced oxygen consumption of biomass in cadmium-amended culture versus control was found. Our results signify that P. aeruginosa san ai is naturally well equipped to overcome and survive high doses of cadmium and, as such, has a great potential for application in bioremediation of cadmium polluted sites. When exposed to cadmium a highly resistant strain P. aeruginosa san ai responds by an increased metalloprotein expression (particularly denitrification proteins), an enhanced respiration, and a pronounced thiol-disulfide protein modifications.![]()
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Affiliation(s)
| | - Milena Rikalović
- Faculty of Applied Ecology Futura
- University of Singidunum
- Belgrade
- Serbia
| | - Gordana Gojgić-Cvijović
- Institute of Chemistry
- Technology and Metallurgy
- Department of Chemistry
- University of Belgrade
- Belgrade
| | | | - Miroslav Vrvić
- Faculty of Chemistry
- University of Belgrade
- Belgrade
- Serbia
| | - Ilija Brčeski
- Faculty of Chemistry
- University of Belgrade
- Belgrade
- Serbia
| | | | - Branka Lončarević
- Institute of Chemistry
- Technology and Metallurgy
- Department of Chemistry
- University of Belgrade
- Belgrade
| | - Kristina Gopčević
- Department of Chemistry
- Faculty of Medicine
- University of Belgrade
- Belgrade
- Serbia
| | - Ivanka Karadžić
- Department of Chemistry
- Faculty of Medicine
- University of Belgrade
- Belgrade
- Serbia
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Li BB, Wang X, Tai L, Ma TT, Shalmani A, Liu WT, Li WQ, Chen KM. NAD Kinases: Metabolic Targets Controlling Redox Co-enzymes and Reducing Power Partitioning in Plant Stress and Development. FRONTIERS IN PLANT SCIENCE 2018; 9:379. [PMID: 29662499 PMCID: PMC5890153 DOI: 10.3389/fpls.2018.00379] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 03/07/2018] [Indexed: 05/03/2023]
Abstract
NAD(H) and NADP(H) are essential co-enzymes which dominantly control a number of fundamental biological processes by acting as reducing power and maintaining the intracellular redox balance of all life kingdoms. As the only enzymes that catalyze NAD(H) and ATP to synthesize NADP(H), NAD Kinases (NADKs) participate in many essential metabolic reactions, redox sensitive regulation, photosynthetic performance and also reactive oxygen species (ROS) homeostasis of cells and therefore, play crucial roles in both development and stress responses of plants. NADKs are highly conserved enzymes in amino acid sequences but have multiple subcellular localization and diverse functions. They may function as monomers, dimers or multimers in cells but the enzymatic properties in plants are not well elucidated yet. The activity of plant NADK is regulated by calcium/calmodulin and plays crucial roles in photosynthesis and redox co-enzyme control. NADK genes are expressed in almost all tissues and developmental stages of plants with specificity for different members. Their transcripts can be greatly stimulated by a number of environmental factors such as pathogenic attack, irritant applications and abiotic stress treatments. Using transgenic approaches, several studies have shown that NADKs are involved in chlorophyll synthesis, photosynthetic efficiency, oxidative stress protection, hormone metabolism and signaling regulation, and therefore contribute to the growth regulation and stress tolerance of plants. In this review, the enzymatic properties and functional mechanisms of plant NADKs are thoroughly investigated based on literature and databases. The results obtained here are greatly advantageous for further exploration of NADK function in plants.
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Alpha-ketoglutarate protects Streptomyces coelicolor from visible light-induced phototoxicity. Biochem Biophys Rep 2017; 9:22-28. [PMID: 29114580 PMCID: PMC5632709 DOI: 10.1016/j.bbrep.2016.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 10/28/2016] [Accepted: 11/03/2016] [Indexed: 01/12/2023] Open
Abstract
It has been known that some Streptomyces species, including the model strain Streptomyces coelicolor, are vulnerable to visible light. Much evidence demonstrated that the phototoxicity induced by visible light is a consequence of the formation of intracellular reactive oxygen species (ROS), which are potentially harmful to cells. In this study, we found that α-ketoglutarate (α-KG) has a protective role against the phototoxicity in S. coelicolor. It could be because that α-KG can detoxify the ROS with the concomitant formation of succinate, which mediates the cells getting into anaerobiosis to produce more NADH and maintain intracellular redox homeostasis, a situation that was demonstrated by overexpressing gdhA in S. coelicolor. This finding, therefore, connects the central metabolites with the bacterial resistance against phototoxicity effect induced by visible light. Streptomyces coelicolor is sensitive to visible light induced phototoxicity. α-ketoglutarate (α-KG) has a protective role against phototoxicity in S. coelicolor. α-KG maintains intracellular NAD/NADH redox homeostasis to resist phototoxicity.
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35
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Svenningsen NB, Damgaard M, Rasmussen M, Pérez-Pantoja D, Nybroe O, Nicolaisen MH. Cupriavidus pinatubonensis AEO106 deals with copper-induced oxidative stress before engaging in biodegradation of the herbicide 4-chloro-2-methylphenoxyacetic acid. BMC Microbiol 2017; 17:211. [PMID: 29084513 PMCID: PMC5663122 DOI: 10.1186/s12866-017-1119-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/19/2017] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Microbial degradation of phenoxy acid (PA) herbicides in agricultural soils is important to minimize herbicide leaching to groundwater reservoirs. Degradation may, however, be hampered by exposure of the degrader bacteria to toxic metals as copper (Cu) in the soil environment. Exposure to Cu leads to accumulation of intracellular reactive oxygen species (ROS) in some bacteria, but it is not known how Cu-derived ROS and an ensuing oxidative stress affect the degradation of PA herbicides. Based on the previously proposed paradigm that bacteria deal with environmental stress before they engage in biodegradation, we studied how the degradation of the PA herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA) by the model PA degrader Cupriavidus pinatubonensis AEO106 was affected by Cu exposure. RESULTS Exposure of C. pinatubonensis in batch culture to sublethal concentrations of Cu increased accumulation of ROS measured by the oxidant sensing probe 2,7-dichlorodihydrofluorescein diacetate and flow cytometry, and resulted in upregulation of a gene encoding a protein belong to the Ohr/OsmC protein family. The ohr/osmC gene was also highly induced by H2O2 exposure suggesting that it is involved in the oxidative stress response in C. pinatubonensis. The increased ROS accumulation and increased expression of the oxidative stress defense coincided with a delay in the catabolic performance, since both expression of the catabolic tfdA gene and MCPA mineralization were delayed compared to unexposed control cells. CONCLUSIONS The current study suggests that Cu-induced ROS accumulation in C. pinatubonensis activates a stress response involving the product of the ohr/osmC gene. Further, the stress response is launched before induction of the catabolic tfdA gene and mineralization occurs.
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Affiliation(s)
- Nanna Bygvraa Svenningsen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C, Denmark
| | - Mette Damgaard
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C, Denmark
| | - Maria Rasmussen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C, Denmark
| | - Danilo Pérez-Pantoja
- Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación, Universidad Tecnológica Metropolitana, Ignacio Valdivieso 2409, San Joaquín, Santiago, Chile
| | - Ole Nybroe
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C, Denmark
| | - Mette Haubjerg Nicolaisen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C, Denmark.
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Lemire J, Alhasawi A, Appanna VP, Tharmalingam S, Appanna VD. Metabolic defence against oxidative stress: the road less travelled so far. J Appl Microbiol 2017; 123:798-809. [PMID: 28609580 DOI: 10.1111/jam.13509] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 05/30/2017] [Accepted: 06/05/2017] [Indexed: 12/28/2022]
Abstract
Bacteria have survived, and many have thrived, since antiquity in the presence of the highly-reactive chalcogen-oxygen (O2 ). They are known to evoke intricate strategies to defend themselves from the reactive by-products of oxygen-reactive oxygen species (ROS). Many of these detoxifying mechanisms have been extensively characterized; superoxide dismutase, catalases, alkyl hydroperoxide reductase and the glutathione (GSH)-cycling system are responsible for neutralizing specific ROS. Meanwhile, a pool of NADPH-the reductive engine of many ROS-combating enzymes-is maintained by metabolic enzymes including, but not exclusively, glucose-6 phosphate dehydrogenase (G6PDH) and NADP-dependent isocitrate dehydrogenase (ICDH-NADP). So, it is not surprising that evidence continues to emerge demonstrating the pivotal role metabolism plays in mitigating ROS toxicity. Stemming from its ability to concurrently decrease the production of the pro-oxidative metabolite, NADH, while augmenting the antioxidative metabolite, NADPH, metabolism is the fulcrum of cellular redox potential. In this review, we will discuss the mounting evidence positioning metabolism and metabolic shifts observed during oxidative stress, as critical strategies microbes utilize to thrive in environments that are rife with ROS. The contribution of ketoacids-moieties capable of non-enzymatic decarboxylation in the presence of oxidants-as ROS scavengers will be elaborated alongside the metabolic pathways responsible for their homeostases. Further, the signalling role of the carboxylic acids generated following the ketoacid-mediated detoxification of the ROS will be commented on within the context of oxidative stress.
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Affiliation(s)
- J Lemire
- The Biofilm Research Group, The Department of Biological Sciences, The University of Calgary, Calgary, AB, Canada
| | - A Alhasawi
- Faculty of Science & Engineering, Laurentian University, Sudbury, ON, Canada
| | - V P Appanna
- Faculty of Science & Engineering, Laurentian University, Sudbury, ON, Canada
| | - S Tharmalingam
- Faculty of Science & Engineering, Laurentian University, Sudbury, ON, Canada
| | - V D Appanna
- Faculty of Science & Engineering, Laurentian University, Sudbury, ON, Canada
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Meylan S, Porter CBM, Yang JH, Belenky P, Gutierrez A, Lobritz MA, Park J, Kim SH, Moskowitz SM, Collins JJ. Carbon Sources Tune Antibiotic Susceptibility in Pseudomonas aeruginosa via Tricarboxylic Acid Cycle Control. Cell Chem Biol 2017; 24:195-206. [PMID: 28111098 DOI: 10.1016/j.chembiol.2016.12.015] [Citation(s) in RCA: 236] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/21/2016] [Accepted: 12/28/2016] [Indexed: 10/20/2022]
Abstract
Metabolically dormant bacteria present a critical challenge to effective antimicrobial therapy because these bacteria are genetically susceptible to antibiotic treatment but phenotypically tolerant. Such tolerance has been attributed to impaired drug uptake, which can be reversed by metabolic stimulation. Here, we evaluate the effects of central carbon metabolite stimulations on aminoglycoside sensitivity in the pathogen Pseudomonas aeruginosa. We identify fumarate as a tobramycin potentiator that activates cellular respiration and generates a proton motive force by stimulating the tricarboxylic acid (TCA) cycle. In contrast, we find that glyoxylate induces phenotypic tolerance by inhibiting cellular respiration with acetyl-coenzyme A diversion through the glyoxylate shunt, despite drug import. Collectively, this work demonstrates that TCA cycle activity is important for both aminoglycoside uptake and downstream lethality and identifies a potential strategy for potentiating aminoglycoside treatment of P. aeruginosa infections.
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Affiliation(s)
- Sylvain Meylan
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Caroline B M Porter
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jason H Yang
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Peter Belenky
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912, USA
| | - Arnaud Gutierrez
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Michael A Lobritz
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Jihye Park
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Sun H Kim
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Samuel M Moskowitz
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - James J Collins
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard-MIT Program, Health Sciences and Technology, Cambridge, MA 02139, USA.
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38
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Duport C, Jobin M, Schmitt P. Adaptation in Bacillus cereus: From Stress to Disease. Front Microbiol 2016; 7:1550. [PMID: 27757102 PMCID: PMC5047918 DOI: 10.3389/fmicb.2016.01550] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/15/2016] [Indexed: 12/23/2022] Open
Abstract
Bacillus cereus is a food-borne pathogen that causes diarrheal disease in humans. After ingestion, B. cereus experiences in the human gastro-intestinal tract abiotic physical variables encountered in food, such as acidic pH in the stomach and changing oxygen conditions in the human intestine. B. cereus responds to environmental changing conditions (stress) by reversibly adjusting its physiology to maximize resource utilization while maintaining structural and genetic integrity by repairing and minimizing damage to cellular infrastructure. As reviewed in this article, B. cereus adapts to acidic pH and changing oxygen conditions through diverse regulatory mechanisms and then exploits its metabolic flexibility to grow and produce enterotoxins. We then focus on the intricate link between metabolism, redox homeostasis, and enterotoxins, which are recognized as important contributors of food-borne disease.
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Affiliation(s)
- Catherine Duport
- Sécurité et Qualité des Produits d'Origine Végétale, UMR0408, Avignon Université, Institut National de la Recherche Agronomique Avignon, France
| | - Michel Jobin
- Sécurité et Qualité des Produits d'Origine Végétale, UMR0408, Avignon Université, Institut National de la Recherche Agronomique Avignon, France
| | - Philippe Schmitt
- Sécurité et Qualité des Produits d'Origine Végétale, UMR0408, Avignon Université, Institut National de la Recherche Agronomique Avignon, France
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Wang L, Zhang J, Kim B, Peng J, Berry SN, Ni Y, Su D, Lee J, Yuan L, Chang YT. Boronic Acid: A Bio-Inspired Strategy To Increase the Sensitivity and Selectivity of Fluorescent NADH Probe. J Am Chem Soc 2016; 138:10394-7. [PMID: 27500425 DOI: 10.1021/jacs.6b05810] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Fluorescent probes have emerged as an essential tool in the molecular recognition events in biological systems; however, due to the complex structures of certain biomolecules, it remains a challenge to design small-molecule fluorescent probes with high sensitivity and selectivity. Inspired by the enzyme-catalyzed reaction between biomolecule and probe, we present a novel combination-reaction two-step sensing strategy to improve sensitivity and selectivity. Based on this strategy, we successfully prepared a turn-on fluorescent reduced nicotinamide adenine dinucleotide (NADH) probe, in which boronic acid was introduced to bind with NADH and subsequently accelerate the sensing process. This probe shows remarkably improved sensitivity (detection limit: 0.084 μM) and selectivity to NADH in the absence of any enzymes. In order to improve the practicality, the boronic acid was further modified to change the measurement conditions from alkalescent (pH 9.5) to physiological environment (pH 7.4). Utilizing these probes, we not only accurately quantified the NADH weight in a health care product but also evaluated intracellular NADH levels in live cell imaging. Thus, these bio-inspired fluorescent probes offer excellent tools for elucidating the roles of NADH in biological systems as well as a practical strategy to develop future sensitive and selective probes for complicated biomolecules.
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Affiliation(s)
- Lu Wang
- Department of Chemistry and Medicinal Chemistry Program, National University of Singapore , Singapore 117543
| | - Jingye Zhang
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University , Shanghai 201203, P. R. China
| | - Beomsue Kim
- Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
| | - Juanjuan Peng
- Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
| | - Stuart N Berry
- Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
| | - Yong Ni
- Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
| | - Dongdong Su
- Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
| | - Jungyeol Lee
- Department of Chemistry and Medicinal Chemistry Program, National University of Singapore , Singapore 117543
| | - Lin Yuan
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, P. R. China
| | - Young-Tae Chang
- Department of Chemistry and Medicinal Chemistry Program, National University of Singapore , Singapore 117543.,Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium , Singapore 117543
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Nikel PI, Pérez-Pantoja D, de Lorenzo V. Pyridine nucleotide transhydrogenases enable redox balance of Pseudomonas putida during biodegradation of aromatic compounds. Environ Microbiol 2016; 18:3565-3582. [PMID: 27348295 DOI: 10.1111/1462-2920.13434] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/23/2016] [Indexed: 11/26/2022]
Abstract
The metabolic versatility of the soil bacterium Pseudomonas putida is reflected by its ability to execute strong redox reactions (e.g., mono- and di-oxygenations) on aromatic substrates. Biodegradation of aromatics occurs via the pathway encoded in the archetypal TOL plasmid pWW0, yet the effect of running such oxidative route on redox balance against the background metabolism of P. putida remains unexplored. To answer this question, the activity of pyridine nucleotide transhydrogenases (that catalyze the reversible interconversion of NADH and NADPH) was inspected under various physiological and oxidative stress regimes. The genome of P. putida KT2440 encodes a soluble transhydrogenase (SthA) and a membrane-bound, proton-pumping counterpart (PntAB). Mutant strains, lacking sthA and/or pntAB, were subjected to a panoply of genetic, biochemical, phenomic and functional assays in cells grown on customary carbon sources (e.g., citrate) versus difficult-to-degrade aromatic substrates. The results consistently indicated that redox homeostasis is compromised in the transhydrogenases-defective variant, rendering the mutant sensitive to oxidants. This metabolic deficiency was, however, counteracted by an increase in the activity of NADP+ -dependent dehydrogenases in central carbon metabolism. Taken together, these observations demonstrate that transhydrogenases enable a redox-adjusting mechanism that comes into play when biodegradation reactions are executed to metabolize unusual carbon compounds.
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Affiliation(s)
- Pablo I Nikel
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Danilo Pérez-Pantoja
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
- Department of Biochemistry and Molecular Biology, Faculty of Biological Sciences, University of Concepción, 4030000 Concepción, Chile
| | - Víctor de Lorenzo
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain.
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Appanna VP, Alhasawi AA, Auger C, Thomas SC, Appanna VD. Phospho-transfer networks and ATP homeostasis in response to an ineffective electron transport chain in Pseudomonas fluorescens. Arch Biochem Biophys 2016; 606:26-33. [PMID: 27431058 DOI: 10.1016/j.abb.2016.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 07/04/2016] [Accepted: 07/14/2016] [Indexed: 02/07/2023]
Abstract
Although oxidative stress is known to impede the tricarboxylic acid (TCA) cycle and oxidative phosphorylation, the nutritionally-versatile microbe, Pseudomonas fluorescens has been shown to proliferate in the presence of hydrogen peroxide (H2O2) and nitrosative stress. In this study we demonstrate the phospho-transfer system that enables this organism to generate ATP was similar irrespective of the carbon source utilized. Despite the diminished activities of enzymes involved in the TCA cycle and in the electron transport chain (ETC), the ATP levels did not appear to be significantly affected in the stressed cells. Phospho-transfer networks mediated by acetate kinase (ACK), adenylate kinase (AK), and nucleoside diphosphate kinase (NDPK) are involved in maintaining ATP homeostasis in the oxidatively-challenged cells. This phospho-relay machinery orchestrated by substrate-level phosphorylation is aided by the up-regulation in the activities of such enzymes like phosphoenolpyruvate carboxylase (PEPC), pyruvate orthophosphate dikinase (PPDK), and phosphoenolpyruvate synthase (PEPS). The enhanced production of phosphoenolpyruvate (PEP) and pyruvate further fuel the synthesis of ATP. Taken together, this metabolic reconfiguration enables the organism to fulfill its ATP need in an O2-independent manner by utilizing an intricate phospho-wire module aimed at maximizing the energy potential of PEP with the participation of AMP.
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Affiliation(s)
- V P Appanna
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E 2C6, Canada
| | - A A Alhasawi
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E 2C6, Canada
| | - C Auger
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E 2C6, Canada
| | - S C Thomas
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E 2C6, Canada
| | - V D Appanna
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E 2C6, Canada.
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Maravić A, Cvjetan S, Konta M, Ladouce R, Martín FA. Proteomic response of β-lactamases-producing Enterobacter cloacae complex strain to cefotaxime-induced stress. Pathog Dis 2016; 74:ftw045. [PMID: 27162211 DOI: 10.1093/femspd/ftw045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2016] [Indexed: 11/14/2022] Open
Abstract
Bacteria of the Enterobacter cloacae complex are among the ten most common pathogens causing nosocomial infections in the USA. Consequently, increased resistance to β-lactam antibiotics, particularly expanded-spectrum cephalosporins like cefotaxime (CTX), poses a serious threat. Differential In-Gel Electrophoresis (DIGE), followed by LC-MS/MS analysis and bioinformatics tools, was employed to investigate the survival mechanisms of a multidrug-resistant E. hormaechei subsp. steigerwaltii 51 carrying several β-lactamase-encoding genes, including the 'pandemic' blaCTX-M-15 After exposing the strain with sub-minimal inhibitory concentration (MIC) of CTX, a total of 1072 spots from the whole-cell proteome were detected, out of which 35 were differentially expressed (P ≤ 0.05, fold change ≥1.5). Almost 50% of these proteins were involved in cell metabolism and energy production, and then cell wall organization/virulence, stress response and transport. This is the first study investigating the whole-cell proteomic response related to the survival of β-lactamases-producing strain, belonging to the E. cloacae complex when exposed to β-lactam antibiotic. Our data support the theory of a multifactorial synergistic effect of diverse proteomic changes occurring in bacterial cells during antibiotic exposure, depicting the complexity of β-lactam resistance and giving us an insight in the key pathways mediating the antibiotic resistance in this emerging opportunistic pathogen.
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Affiliation(s)
- Ana Maravić
- Department of Biology, Faculty of Science, University of Split, Teslina 12, 21000 Split, Croatia
| | - Svjetlana Cvjetan
- Department of Molecular Biology, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia Mediterranean Institute for Life Sciences, Meštovićevo šetalište 45, 21000 Split, Croatia
| | - Marina Konta
- Mediterranean Institute for Life Sciences, Meštovićevo šetalište 45, 21000 Split, Croatia
| | - Romain Ladouce
- Mediterranean Institute for Life Sciences, Meštovićevo šetalište 45, 21000 Split, Croatia
| | - Fernando A Martín
- Mediterranean Institute for Life Sciences, Meštovićevo šetalište 45, 21000 Split, Croatia
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Kim JN. Roles of two RyhB paralogs in the physiology of Salmonella enterica. Microbiol Res 2016; 186-187:146-52. [PMID: 27242152 DOI: 10.1016/j.micres.2016.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 04/07/2016] [Accepted: 04/10/2016] [Indexed: 11/18/2022]
Abstract
Salmonella has evolved complicated regulatory systems to regulate the expression of virulence determinants that are acquired by horizontal gene transfer in response to various environmental niches. Among these, small RNA (sRNA)-mediated regulation exhibits unique features, distinct from those of protein factor-mediated regulation, which may provide benefits for a pathogen coping with the complex stress conditions encountered during host infection. Specifically, iron acquisition by this pathogenic bacterium is important for cellular processes such as energy metabolism and DNA replication. Many studies on the role of RyhB sRNA have begun to unveil the essential nature of iron acquisition in allowing the organism to persist and develop pathogenicity. The Salmonella genome encodes two RyhB paralogs, RyhB-1 and RyhB-2, which are known to act singularly or together on target expression. Based on the mechanism of Escherichia coli RyhB function, this review proposes a possible model to show how two Salmonella RyhB paralogs regulate the level of target mRNAs by sensing environmental inputs or conditions. This review also describes the involvement of Salmonella RyhBs in diverse functions including nitrate homeostasis, adaptive system to oxidative stress, and intracellular survival. Thus, the two Salmonella RyhBs play a critical role in the regulation of gene expression that appears to be essential for persistence and pathogenesis of Salmonella spp.
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Affiliation(s)
- Jeong Nam Kim
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL 32610, United States.
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44
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Alhasawi A, Thomas SC, Appanna VD. Metabolic networks to generate pyruvate, PEP and ATP from glycerol in Pseudomonas fluorescens. Enzyme Microb Technol 2016; 85:51-6. [PMID: 26920481 DOI: 10.1016/j.enzmictec.2016.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/07/2016] [Accepted: 01/15/2016] [Indexed: 01/02/2023]
Abstract
Glycerol is a major by-product of the biodiesel industry. In this study we report on the metabolic networks involved in its transformation into pyruvate, phosphoenolpyruvate (PEP) and ATP. When the nutritionally-versatile Pseudomonas fluorescens was exposed to hydrogen peroxide (H2O2) in a mineral medium with glycerol as the sole carbon source, the microbe reconfigured its metabolism to generate adenosine triphosphate (ATP) primarily via substrate-level phosphorylation (SLP). This alternative ATP-producing stratagem resulted in the synthesis of copious amounts of PEP and pyruvate. The production of these metabolites was mediated via the enhanced activities of such enzymes as pyruvate carboxylase (PC) and phosphoenolpyruvate carboxylase (PEPC). The high energy PEP was subsequently converted into ATP with the aid of pyruvate phosphate dikinase (PPDK), phosphoenolpyruvate synthase (PEPS) and pyruvate kinase (PK) with the concomitant formation of pyruvate. The participation of the phospho-transfer enzymes like adenylate kinase (AK) and acetate kinase (ACK) ensured the efficiency of this O2-independent energy-generating machinery. The increased activity of glycerol dehydrogenase (GDH) in the stressed bacteria provided the necessary precursors to fuel this process. This H2O2-induced anaerobic life-style fortuitously evokes metabolic networks to an effective pathway that can be harnessed into the synthesis of ATP, PEP and pyruvate. The bioconversion of glycerol to pyruvate will offer interesting economic benefit.
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Affiliation(s)
- Azhar Alhasawi
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E2C6, Canada
| | - Sean C Thomas
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E2C6, Canada
| | - Vasu D Appanna
- Faculty of Science and Engineering, Laurentian University, Sudbury, ON P3E2C6, Canada.
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Thomas SC, Alhasawi A, Auger C, Omri A, Appanna VD. The role of formate in combatting oxidative stress. Antonie van Leeuwenhoek 2015; 109:263-71. [PMID: 26626058 DOI: 10.1007/s10482-015-0629-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 11/28/2015] [Indexed: 01/14/2023]
Abstract
The interaction of keto-acids with reactive oxygen species (ROS) is known to produce the corresponding carboxylic acid with the concomitant formation of CO2. Formate is liberated when the keto-acid glyoxylate neutralizes ROS. Here we report on how formate is involved in combating oxidative stress in the nutritionally-versatile Pseudomonas fluorescens. When the microbe was subjected to hydrogen peroxide (H2O2), the levels of formate were 8 and two-fold higher in the spent fluid and the soluble cell-free extracts obtained in the stressed cultures compared to the controls respectively. Formate was subsequently utilized as a reducing force to generate NADPH and succinate. The former is mediated by formate dehydrogenase (FDH-NADP), whose activity was enhanced in the stressed cells. Fumarate reductase that catalyzes the conversion of fumarate into succinate was also markedly increased in the stressed cells. These enzymes were modulated by H2O2. While the stressed whole cells produced copious amounts of formate in the presence of glycine, the cell-free extracts synthesized ATP and succinate from formate. Although the exact role of formate in anti-oxidative defence has to await further investigation, the data in this report suggest that this carboxylic acid may be a potent reductive force against oxidative stress.
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Affiliation(s)
- Sean C Thomas
- Faculty of Science, Engineering and Architecture, Laurentian University, Sudbury, ON, P3E 2C6, Canada
| | - Azhar Alhasawi
- Faculty of Science, Engineering and Architecture, Laurentian University, Sudbury, ON, P3E 2C6, Canada
| | - Christopher Auger
- Faculty of Science, Engineering and Architecture, Laurentian University, Sudbury, ON, P3E 2C6, Canada
| | - Abdelwahab Omri
- Faculty of Science, Engineering and Architecture, Laurentian University, Sudbury, ON, P3E 2C6, Canada
| | - Vasu D Appanna
- Faculty of Science, Engineering and Architecture, Laurentian University, Sudbury, ON, P3E 2C6, Canada.
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46
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Hong EJ, Kim P, Kim ES, Kim Y, Lee HS. Involvement of the osrR gene in the hydrogen peroxide-mediated stress response of Corynebacterium glutamicum. Res Microbiol 2015; 167:20-8. [PMID: 26433092 DOI: 10.1016/j.resmic.2015.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 06/30/2015] [Accepted: 09/22/2015] [Indexed: 01/19/2023]
Abstract
A transcriptional profile of the H2O2-adapted Corynebacterium glutamicum HA strain reveals a list of upregulated regulatory genes. Among them, we selected ORF NCgl2298, designated osrR and analyzed its role in H2O2 adaptation. The osrR-deleted (ΔosrR) mutant had defective growth in minimal medium, which was even more pronounced in an osrR deletion mutant of an HA strain. The ΔosrR strain displayed increased sensitivity to H2O2. In addition to H2O2 sensitivity, the ΔosrR strain was found to be temperature-sensitive at 37 °C. 2D-PAGE analysis of the ΔosrR mutant found that MetE and several other proteins involved in redox metabolism were affected by the mutation. Accordingly, the NADPH/NADP(+) ratio of the ΔosrR strain (0.85) was much lower than that of the wild-type strain (2.01). In contrast, the NADH/NAD(+) ratio of the mutant (0.54) was considerably higher than that of the wild-type (0.21). Based on these findings, we propose that H2O2-detoxifying metabolic systems, excluding those involving catalase, are present in C. glutamicum and are regulated, in part, by osrR.
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Affiliation(s)
- Eun-Ji Hong
- Department of Biotechnology and Bioinformatics, Korea University, 2511 Sejong-ro, Sejong-si 339-700, Republic of Korea.
| | - Pil Kim
- Department of Biotechnology, The Catholic University of Korea, Bucheon, Gyeonggi 420-743, Republic of Korea.
| | - Eung-Soo Kim
- Department of Biological Engineering, Inha University, Incheon 402-751, Republic of Korea.
| | - Younhee Kim
- Department of Korean Medicine, Semyung University, 65 Semyeong-ro, Jecheon-si, Chungbuk 390-711, Republic of Korea.
| | - Heung-Shick Lee
- Department of Biotechnology and Bioinformatics, Korea University, 2511 Sejong-ro, Sejong-si 339-700, Republic of Korea.
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Svenningsen NB, Pérez-Pantoja D, Nikel PI, Nicolaisen MH, de Lorenzo V, Nybroe O. Pseudomonas putida mt-2 tolerates reactive oxygen species generated during matric stress by inducing a major oxidative defense response. BMC Microbiol 2015; 15:202. [PMID: 26445482 PMCID: PMC4595014 DOI: 10.1186/s12866-015-0542-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 10/02/2015] [Indexed: 01/09/2023] Open
Abstract
Background Soil bacteria typically thrive in water-limited habitats that cause an inherent matric stress to the cognate cells. Matric stress gives rise to accumulation of intracellular reactive oxygen species (ROS), which in turn may induce oxidative stress, and even promote mutagenesis. However, little is known about the impact of ROS induced by water limitation on bacteria performing important processes as pollutant biodegradation in the environment. We have rigorously examined the physiological consequences of the rise of intracellular ROS caused by matric stress for the toluene- and xylene-degrading soil bacterium Pseudomonas putida mt-2. Methods For the current experiments, controlled matric potential stress was delivered to P. putida cells by addition of polyethylene glycol to liquid cultures, and ROS formation in individual cells monitored by a specific dye. The physiological response to ROS was then quantified by both RT-qPCR of RNA transcripts from genes accredited as proxies of oxidative stress and the SOS response along with cognate transcriptional GFP fusions to the promoters of the same genes. Results Extensive matric stress at −1.5 MPa clearly increased intracellular accumulation of ROS. The expression of the two major oxidative defense genes katA and ahpC, as well as the hydroperoxide resistance gene osmC, was induced under matric stress. Different induction profiles of the reporters were related to the severity of the stress. To determine if matric stress lead to induction of the SOS-response, we constructed a DNA damage-inducible bioreporter based on the LexA-controlled phage promoter PPP3901. According to bioreporter analysis, this gene was expressed during extensive matric stress. Despite this DNA-damage mediated gene induction, we observed no increase in the mutation frequency as monitored by emergence of rifampicin-resistant colonies. Conclusions Under conditions of extensive matric stress, we observed a direct link between matric stress, ROS formation, induction of ROS-detoxifying functions and (partial) activation of the SOS system. However, such a stress-response regime did not translate into a general DNA mutagenesis status. Taken together, the data suggest that P. putida mt-2 can cope with this archetypal environmental stress while preserving genome stability, a quality that strengthens the status of this bacterium for biotechnological purposes.
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Affiliation(s)
- Nanna B Svenningsen
- Department of Plant and Environmental Sciences, Section of Genetics and Microbiology, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Danilo Pérez-Pantoja
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC), C/ Darwin 3, 28049, Madrid, Spain.
| | - Pablo I Nikel
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC), C/ Darwin 3, 28049, Madrid, Spain.
| | - Mette H Nicolaisen
- Department of Plant and Environmental Sciences, Section of Genetics and Microbiology, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Víctor de Lorenzo
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC), C/ Darwin 3, 28049, Madrid, Spain.
| | - Ole Nybroe
- Department of Plant and Environmental Sciences, Section of Genetics and Microbiology, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
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Booth SC, Weljie AM, Turner RJ. Metabolomics reveals differences of metal toxicity in cultures of Pseudomonas pseudoalcaligenes KF707 grown on different carbon sources. Front Microbiol 2015; 6:827. [PMID: 26347721 PMCID: PMC4538868 DOI: 10.3389/fmicb.2015.00827] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/27/2015] [Indexed: 12/23/2022] Open
Abstract
Co-contamination of metals and organic pollutants is a global problem as metals interfere with the metabolism of complex organics by bacteria. Based on a prior observation that metal tolerance was altered by the sole carbon source being used for growth, we sought to understand how metal toxicity specifically affects bacteria using an organic pollutant as their sole carbon source. To this end metabolomics was used to compare cultures of Pseudomonas pseudoalcaligenes KF707 grown on either biphenyl (Bp) or succinate (Sc) as the sole carbon source in the presence of either aluminum (Al) or copper (Cu). Using multivariate statistical analysis it was found that the metals caused perturbations to more cellular processes in the cultures grown on Bp than those grown on Sc. Al induced many changes that were indicative of increased oxidative stress as metabolites involved in DNA damage and protection, the Krebs cycle and anti-oxidant production were altered. Cu also caused metabolic changes that were indicative of similar stress, as well as appearing to disrupt other key enzymes such as fumarase. Additionally, both metals caused the accumulation of Bp degradation intermediates indicating that they interfered with Bp metabolism. Together these results provide a basic understanding of how metal toxicity specifically affects bacteria at a biochemical level during the degradation of an organic pollutant and implicate the catabolism of this carbon source as a major factor that exacerbates metal toxicity.
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Affiliation(s)
- Sean C Booth
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada
| | - Aalim M Weljie
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada ; Department of Systems Pharmacology and Translational Therapeutics, Smilow Centre for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA, USA
| | - Raymond J Turner
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada ; Biofilm Research Group, University of Calgary, Calgary AB, Canada
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49
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Auger C, Alhasawi A, Contavadoo M, Appanna VD. Dysfunctional mitochondrial bioenergetics and the pathogenesis of hepatic disorders. Front Cell Dev Biol 2015; 3:40. [PMID: 26161384 PMCID: PMC4479819 DOI: 10.3389/fcell.2015.00040] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 06/12/2015] [Indexed: 12/18/2022] Open
Abstract
The liver is involved in a variety of critical biological functions including the homeostasis of glucose, fatty acids, amino acids, and the synthesis of proteins that are secreted in the blood. It is also at the forefront in the detoxification of noxious metabolites that would otherwise upset the functioning of the body. As such, this vital component of the mammalian system is exposed to a notable quantity of toxicants on a regular basis. It therefore comes as no surprise that there are over a hundred disparate hepatic disorders, encompassing such afflictions as fatty liver disease, hepatitis, and liver cancer. Most if not all of liver functions are dependent on energy, an ingredient that is primarily generated by the mitochondrion, the power house of all cells. This organelle is indispensable in providing adenosine triphosphate (ATP), a key effector of most biological processes. Dysfunctional mitochondria lead to a shortage in ATP, the leakage of deleterious reactive oxygen species (ROS), and the excessive storage of fats. Here we examine how incapacitated mitochondrial bioenergetics triggers the pathogenesis of various hepatic diseases. Exposure of liver cells to detrimental environmental hazards such as oxidative stress, metal toxicity, and various xenobiotics results in the inactivation of crucial mitochondrial enzymes and decreased ATP levels. The contribution of the latter to hepatic disorders and potential therapeutic cues to remedy these conditions are elaborated.
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Affiliation(s)
- Christopher Auger
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Azhar Alhasawi
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Manuraj Contavadoo
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
| | - Vasu D Appanna
- Faculty of Science and Engineering, Laurentian University Greater Sudbury, ON, Canada
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50
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Madeira JP, Alpha-Bazin B, Armengaud J, Duport C. Time dynamics of the Bacillus cereus exoproteome are shaped by cellular oxidation. Front Microbiol 2015; 6:342. [PMID: 25954265 PMCID: PMC4406070 DOI: 10.3389/fmicb.2015.00342] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/07/2015] [Indexed: 01/18/2023] Open
Abstract
At low density, Bacillus cereus cells release a large variety of proteins into the extracellular medium when cultivated in pH-regulated, glucose-containing minimal medium, either in the presence or absence of oxygen. The majority of these exoproteins are putative virulence factors, including toxin-related proteins. Here, B. cereus exoproteome time courses were monitored by nanoLC-MS/MS under low-oxidoreduction potential (ORP) anaerobiosis, high-ORP anaerobiosis, and aerobiosis, with a specific focus on oxidative-induced post-translational modifications of methionine residues. Principal component analysis (PCA) of the exoproteome dynamics indicated that toxin-related proteins were the most representative of the exoproteome changes, both in terms of protein abundance and their methionine sulfoxide (Met(O)) content. PCA also revealed an interesting interconnection between toxin-, metabolism-, and oxidative stress-related proteins, suggesting that the abundance level of toxin-related proteins, and their Met(O) content in the B. cereus exoproteome, reflected the cellular oxidation under both aerobiosis and anaerobiosis.
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Affiliation(s)
- Jean-Paul Madeira
- UMR408, Sécurité et Qualité des Produits d'Origine Végétale, Université d'Avignon Avignon, France ; INRA, UMR408, Sécurité et Qualité des Produits d' Origine Végétale Avignon, France ; Commissariat à l'énergie Atomique et aux Énergies Alternatives (CEA), Direction des Sciences du Vivant (DSV), IBEB, Li2D Bagnols sur Cèze, France
| | - Béatrice Alpha-Bazin
- Commissariat à l'énergie Atomique et aux Énergies Alternatives (CEA), Direction des Sciences du Vivant (DSV), IBEB, Li2D Bagnols sur Cèze, France
| | - Jean Armengaud
- Commissariat à l'énergie Atomique et aux Énergies Alternatives (CEA), Direction des Sciences du Vivant (DSV), IBEB, Li2D Bagnols sur Cèze, France
| | - Catherine Duport
- UMR408, Sécurité et Qualité des Produits d'Origine Végétale, Université d'Avignon Avignon, France ; INRA, UMR408, Sécurité et Qualité des Produits d' Origine Végétale Avignon, France
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