1
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Mukherjee P, Mazumder A. Macromolecular crowding has opposite effects on two critical sub-steps of transcription initiation. FEBS Lett 2024; 598:1022-1033. [PMID: 38479985 PMCID: PMC7615953 DOI: 10.1002/1873-3468.14851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 02/12/2024] [Accepted: 02/19/2024] [Indexed: 04/12/2024]
Abstract
Transcription initiation, the first step in gene expression, has been studied extensively in dilute buffer, a condition which fails to consider the crowded environment in live cells. Recent reports indicate the kinetics of promoter escape is altered in crowded conditions for a consensus bacterial promoter. Here, we use a real-time fluorescence enhancement assay to study the kinetics of unwound bubble formation and promoter escape for three separate promoters. We find that the effect of crowding on transcription initiation is complex, with lower rates of unwound bubble formation, higher rates of promoter escape, and large variations depending on promoter identity. Based on our results, we suggest that altered conditions of crowding inside a live cell can trigger global changes.
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Affiliation(s)
- Pratip Mukherjee
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre, Ghaziabad, India
| | - Abhishek Mazumder
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
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2
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Thani AB. DNA supercoiling and regulation of intrinsic β-lactamase in pathogenic Escherichia coli. Arch Microbiol 2023; 205:385. [PMID: 37980630 DOI: 10.1007/s00203-023-03716-4] [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: 07/03/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 11/21/2023]
Abstract
This review addresses the involvement of DNA supercoiling in the development of virulence and antibiotic profiles for uropathogenic Escherichia coli and the emergence of new pathotypes such as strain ST131 (serotype O25:H4). The mechanism suggests a role for topoisomerase enzymes and associated mutations in altering the chromosomal supercoiling state and introducing the required DNA twists for expression of intrinsic β-lactamase by ampC and certain virulence factors. In Escherichia coli, constitutive hyperexpression of intrinsic ampC is associated with specific mutations in the promoter and attenuator regions. However, many reports have documented the involvement of slow growth interventions in the expression of intrinsic resistance determinants. There is evidence that a stationary phase transcriptional switch protein, "BolA," is involved in the expression of the intrinsic ampC gene under starvation conditions. The process involves changes in the activity of the enzyme "gyrase," which leads to a change in the chromosomal DNA topology. Consequently, the DNA is relaxed, and the expression of the bolA gene is upregulated. The evolution of the extraintestinal pathogenic E. coli strain ST131 has demonstrated successful adaptability to various stress conditions and conferred compensatory mutations that endowed the microbe with resistance to fluoroquinolones and β-lactams. The results of this study provided new insights into the evidence for the influence of DNA topology in the expression of virulence genes and various determinants of antibiotic resistance (e.g., the intrinsic ampC gene) in Escherichia coli pathotypes.
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Affiliation(s)
- Ali Bin Thani
- Department of Biology, College of Science, University of Bahrain, Zallaq, Kingdom of Bahrain.
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3
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Biswas P, Sengupta S, Nagaraja V. Evolution of YacG to safeguard DNA gyrase from external perturbation. Res Microbiol 2023; 174:104093. [PMID: 37343614 DOI: 10.1016/j.resmic.2023.104093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/10/2023] [Accepted: 06/14/2023] [Indexed: 06/23/2023]
Abstract
Cells have evolved strategies to safeguard their genome integrity. We describe a mechanism to counter double strand breaks in the chromosome that involves the protection of an essential housekeeping enzyme from external agents. YacG is a DNA gyrase inhibitory protein from Escherichia coli that protects the bacterium from the cytotoxic effects of catalytic inhibitors as well as cleavage-complex stabilizers of DNA gyrase. By virtue of blocking the primary DNA binding site of the enzyme, YacG prevents the accumulation of double strand breaks induced by gyrase poisons. It also enables the bacterium to resist the growth-inhibitory property of novobiocin. Gyrase poison-induced oxidative stress upregulates YacG production, probably as a cellular response to counter DNA damage. YacG-mediated protection of the genome is specific for gyrase targeting agents as the protection is not observed from the action of general DNA damaging agents. YacG also intensifies the transcription stress induced by rifampicin substantiating the importance of gyrase activity during transcription. Although essential for bacterial survival, DNA gyrase often gets entrapped by external inhibitors and poisons, resulting in cell death. The existence of YacG to specifically protect an essential housekeeping enzyme might be a strategy adopted by bacteria for competitive fitness advantage.
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Affiliation(s)
- Priti Biswas
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata-700073, India.
| | - Sugopa Sengupta
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata-700073, India.
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.
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4
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Dash S, Palma CSD, Baptista ISC, Almeida BLB, Bahrudeen MNM, Chauhan V, Jagadeesan R, Ribeiro AS. Alteration of DNA supercoiling serves as a trigger of short-term cold shock repressed genes of E. coli. Nucleic Acids Res 2022; 50:8512-8528. [PMID: 35920318 PMCID: PMC9410904 DOI: 10.1093/nar/gkac643] [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: 01/31/2022] [Revised: 07/07/2022] [Accepted: 07/20/2022] [Indexed: 11/14/2022] Open
Abstract
Cold shock adaptability is a key survival skill of gut bacteria of warm-blooded animals. Escherichia coli cold shock responses are controlled by a complex multi-gene, timely-ordered transcriptional program. We investigated its underlying mechanisms. Having identified short-term, cold shock repressed genes, we show that their responsiveness is unrelated to their transcription factors or global regulators, while their single-cell protein numbers' variability increases after cold shock. We hypothesized that some cold shock repressed genes could be triggered by high propensity for transcription locking due to changes in DNA supercoiling (likely due to DNA relaxation caused by an overall reduction in negative supercoiling). Concomitantly, we found that nearly half of cold shock repressed genes are also highly responsive to gyrase inhibition (albeit most genes responsive to gyrase inhibition are not cold shock responsive). Further, their response strengths to cold shock and gyrase inhibition correlate. Meanwhile, under cold shock, nucleoid density increases, and gyrases and nucleoid become more colocalized. Moreover, the cellular energy decreases, which may hinder positive supercoils resolution. Overall, we conclude that sensitivity to diminished negative supercoiling is a core feature of E. coli's short-term, cold shock transcriptional program, and could be used to regulate the temperature sensitivity of synthetic circuits.
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Affiliation(s)
- Suchintak Dash
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Cristina S D Palma
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Ines S C Baptista
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Bilena L B Almeida
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Mohamed N M Bahrudeen
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Vatsala Chauhan
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Rahul Jagadeesan
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland
| | - Andre S Ribeiro
- Laboratory of Biosystem Dynamics, Faculty of Medicine and Health Technology, Tampere University, Tampere 33520, Finland.,Center of Technology and Systems (CTS-Uninova), NOVA University of Lisbon 2829-516, Monte de Caparica, Portugal
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5
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Morawska LP, Detert Oude Weme RGJ, Frenzel E, Dirkzwager M, Hoffmann T, Bremer E, Kuipers OP. Stress-induced activation of the proline biosynthetic pathway in Bacillus subtilis: a population-wide and single-cell study of the osmotically controlled proHJ promoter. Microb Biotechnol 2022; 15:2411-2425. [PMID: 35593133 PMCID: PMC9437891 DOI: 10.1111/1751-7915.14073] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/20/2022] [Accepted: 04/27/2022] [Indexed: 12/01/2022] Open
Abstract
Bacillus subtilis, in its natural habitat, is regularly exposed to rapid changes in the osmolarity of its surrounding. As its primary survival strategy, it accumulates large amounts of the compatible solute proline by activating the de novo proline biosynthesis pathway and exploiting the glutamate pools. This osmotically‐induced biosynthesis requires activation of a SigA‐type promoter that drives the expression of the proHJ operon. Population‐wide studies have shown that the activity of the proHJ promoter correlates with the increased osmotic pressure of the environment. Therefore, the activation of the proHJ transcription should be an adequate measure of the adaptation to osmotic stress through proline synthesis in the absence of other osmoprotectants. In this study, we investigate the kinetics of the proHJ promoter activation and the early adaptation to mild osmotic upshift at the single‐cell level. Under these conditions, we observed a switching point and heterogeneous proline biosynthesis gene expression, where the subpopulation of cells showing active proHJ transcription is able to continuously divide, and those unresponsive to osmotic stress remain dormant. Additionally, we demonstrate that bactericidal antibiotics significantly upregulate proHJ transcription in the absence of externally imposed osmotic pressure, suggesting that the osmotically‐controlled proline biosynthesis pathway is also involved in the antibiotic‐mediated stress response.
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Affiliation(s)
- Luiza P Morawska
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Ruud G J Detert Oude Weme
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Elrike Frenzel
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Maarten Dirkzwager
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Tamara Hoffmann
- Department of Biology, Laboratory for Microbiology, Philipps University Marburg, Karl-von-Frisch-Str.8, D-35032, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Karl-von-Frisch Strasse 14, 35043, Marburg, Germany
| | - Erhard Bremer
- Department of Biology, Laboratory for Microbiology, Philipps University Marburg, Karl-von-Frisch-Str.8, D-35032, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Karl-von-Frisch Strasse 14, 35043, Marburg, Germany
| | - Oscar P Kuipers
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
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6
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Klähn S, Mikkat S, Riediger M, Georg J, Hess WR, Hagemann M. Integrative analysis of the salt stress response in cyanobacteria. Biol Direct 2021; 16:26. [PMID: 34906211 PMCID: PMC8670252 DOI: 10.1186/s13062-021-00316-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/29/2021] [Indexed: 12/24/2022] Open
Abstract
Microorganisms evolved specific acclimation strategies to thrive in environments of high or fluctuating salinities. Here, salt acclimation in the model cyanobacterium Synechocystis sp. PCC 6803 was analyzed by integrating transcriptomic, proteomic and metabolomic data. A dynamic reorganization of the transcriptome occurred during the first hours after salt shock, e.g. involving the upregulation of genes to activate compatible solute biochemistry balancing osmotic pressure. The massive accumulation of glucosylglycerol then had a measurable impact on the overall carbon and nitrogen metabolism. In addition, we observed the coordinated induction of putative regulatory RNAs and of several proteins known for their involvement in other stress responses. Overall, salt-induced changes in the proteome and transcriptome showed good correlations, especially among the stably up-regulated proteins and their transcripts. We define an extended salt stimulon comprising proteins directly or indirectly related to compatible solute metabolism, ion and water movements, and a distinct set of regulatory RNAs involved in post-transcriptional regulation. Our comprehensive data set provides the basis for engineering cyanobacterial salt tolerance and to further understand its regulation.
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Affiliation(s)
- Stephan Klähn
- Department of Solar Materials, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
- Faculty of Biology, Genetics and Experimental Bioinformatics, University of Freiburg, Freiburg, Germany
| | - Stefan Mikkat
- Core Facility Proteome Analysis, Rostock University Medical Center, Rostock, Germany
| | - Matthias Riediger
- Faculty of Biology, Genetics and Experimental Bioinformatics, University of Freiburg, Freiburg, Germany
| | - Jens Georg
- Faculty of Biology, Genetics and Experimental Bioinformatics, University of Freiburg, Freiburg, Germany
| | - Wolfgang R. Hess
- Faculty of Biology, Genetics and Experimental Bioinformatics, University of Freiburg, Freiburg, Germany
| | - Martin Hagemann
- Department of Plant Physiology, Institute of Biosciences, University of Rostock, A.-Einstein-Str. 3, 18059 Rostock, Germany
- Department Life, Light and Matter, University of Rostock, Rostock, Germany
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7
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Restoring Global Gene Regulation through Experimental Evolution Uncovers a NAP (Nucleoid-Associated Protein)-Like Behavior of Crp/Cap. mBio 2021; 12:e0202821. [PMID: 34700380 PMCID: PMC8546631 DOI: 10.1128/mbio.02028-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
How do hierarchical gene regulation networks evolve in bacteria? Nucleoid-associated proteins (NAPs) influence the overall structure of bacterial genomes, sigma factors and global transcription factors (TFs) control thousands of genes, and many operons are regulated by highly specific TFs that in turn are controlled allosterically by cellular metabolites. These regulatory hierarchies have been shaped by millions of years of evolution to optimize fitness in response to changing environmental conditions, but it is unclear how NAPs and TFs relate and have evolved together. Cyclic AMP (cAMP) receptor protein (Crp) is the paradigmatic global TF in Escherichia coli, and here we report that mutations in the topA gene compensate for loss of cAMP, showing that the interplay between Crp and the supercoiling status of promoters is key to global stress response. Furthermore, we observed an effect of apoCrp on gene expression in the absence of its effector cAMP. This provides support for the proposed NAP-like role for Crp, suggesting that it represents an intermediate point in the evolution of a ligand-controlled TF from a NAP.
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8
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Wason S, Verma T, Subbiah J. Validation of process technologies for enhancing the safety of low-moisture foods: A review. Compr Rev Food Sci Food Saf 2021; 20:4950-4992. [PMID: 34323364 DOI: 10.1111/1541-4337.12800] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 06/03/2021] [Accepted: 06/10/2021] [Indexed: 01/03/2023]
Abstract
The outbreaks linked to foodborne illnesses in low-moisture foods are frequently reported due to the occurrence of pathogenic microorganisms such as Salmonella Spp. Bacillus cereus, Clostridium spp., Cronobacter sakazakii, Escherichia coli, and Staphylococcus aureus. The ability of the pathogens to withstand the dry conditions and to develop resistance to heat is regarded as the major concern for the food industry dealing with low-moisture foods. In this regard, the present review is aimed to discuss the importance and the use of novel thermal and nonthermal technologies such as radiofrequency, steam pasteurization, plasma, and gaseous technologies for decontamination of foodborne pathogens in low-moisture foods and their microbial inactivation mechanisms. The review also summarizes the various sources of contamination and the factors influencing the survival and thermal resistance of pathogenic microorganisms in low-moisture foods. The literature survey indicated that the nonthermal techniques such as CO2 , high-pressure processing, and so on, may not offer effective microbial inactivation in low-moisture foods due to their insufficient moisture content. On the other hand, gases can penetrate deep inside the commodities and pores due to their higher diffusion properties and are regarded to have an advantage over thermal and other nonthermal processes. Further research is required to evaluate newer intervention strategies and combination treatments to enhance the microbial inactivation in low-moisture foods without significantly altering their organoleptic and nutritional quality.
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Affiliation(s)
- Surabhi Wason
- Department of Food Science, University of Arkansas System Division of Agriculture, Fayetteville, Arkansas, USA
| | - Tushar Verma
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Jeyamkondan Subbiah
- Department of Food Science, University of Arkansas System Division of Agriculture, Fayetteville, Arkansas, USA.,Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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9
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Yang H, Zhang L, Li J, Jin Y, Zou J, Huang J, Zhou R, Huang M, Wu C. Cell surface properties and transcriptomic analysis of cross protection provided between heat adaptation and acid stress in Tetragenococcus halophilus. Food Res Int 2021; 140:110005. [PMID: 33648238 DOI: 10.1016/j.foodres.2020.110005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 12/01/2020] [Accepted: 12/08/2020] [Indexed: 11/16/2022]
Abstract
Cross protection is a widely existed phenomenon in microorganisms which subjected to a mild stress develop tolerance to other stresses, yet the underlying mechanisms for this protection have not been fully elucidated. Here, we report that heat preadaptation induced cross protection against acid stress in Tetragenococcus halophilus, and the cross protective mechanisms were revealed based on cell surface characterizations and transcriptomic analysis. The results showed that heat preadaptation of T. halophilus at 45 °C for 1.5 h improved the acid tolerance of cells at pH 2.5, and the preadapted cells exhibited higher pHi compared with the un-preadapted cells during acid stress. Analysis of the cell surface properties suggested that the heat-treated cells displayed smoother surface, lower roughness and higher integrity than those of untreated cells. Meanwhile, the distributions of membrane fatty acids also changed in response to acid stress, and the treated cells reveled lower ratio of unsaturated to saturated fatty acids. RNA-Sequencing was employed to further elucidate the cross protective mechanism induced by heat preadaptation, and the results showed that the differentially expressed genes (DGEs) were mainly involved in cellular metabolism and membrane transport during heat preadaptation. A detailed analysis of gene expression profile of cells between heat treated and untreated revealed that genes associated with energy metabolism, amino acid metabolism and genetic information processing were induced upon heat stress. Results presented in this study may broaden our understanding on cross protection and provide a potential strategy to enhance the performance of cells during industrial processes.
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Affiliation(s)
- Huan Yang
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu 610065, China
| | - Liang Zhang
- Luzhou Laojiao Group Co., Ltd, Luzhou 646000, China
| | - Jinsong Li
- Luzhou Laojiao Group Co., Ltd, Luzhou 646000, China
| | - Yao Jin
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu 610065, China
| | | | - Jun Huang
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu 610065, China
| | - Rongqing Zhou
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu 610065, China
| | - Mingquan Huang
- Beijing Laboratory of Food Quality and Safety, Beijing Technology and Business University, Beijing 100048, China.
| | - Chongde Wu
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu 610065, China; Beijing Laboratory of Food Quality and Safety, Beijing Technology and Business University, Beijing 100048, China.
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10
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Pozdeev G, Mogre A, Dorman CJ. Consequences of producing DNA gyrase from a synthetic gyrBA operon in Salmonella enterica serovar Typhimurium. Mol Microbiol 2021; 115:1410-1429. [PMID: 33539568 PMCID: PMC8359277 DOI: 10.1111/mmi.14689] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/17/2022]
Abstract
DNA gyrase is an essential type II topoisomerase that is composed of two subunits, GyrA and GyrB, and has an A2B2 structure. Although the A and B subunits are required in equal proportions to form DNA gyrase, the gyrA and gyrB genes that encode them in Salmonella (and in many other bacteria) are at separate locations on the chromosome, are under separate transcriptional control, and are present in different copy numbers in rapidly growing bacteria. In wild‐type Salmonella, gyrA is near the chromosome's replication terminus, while gyrB is near the origin. We generated a synthetic gyrBA operon at the oriC‐proximal location of gyrB to test the significance of the gyrase gene position for Salmonella physiology. Although the strain producing gyrase from an operon had a modest alteration to its DNA supercoiling set points, most housekeeping functions were unaffected. However, its SPI‐2 virulence genes were expressed at a reduced level and its survival was reduced in macrophage. Our data reveal that the horizontally acquired SPI‐2 genes have a greater sensitivity to disturbance of DNA topology than the core genome and we discuss its significance in the context of Salmonella genome evolution and the gyrA and gyrB gene arrangements found in other bacteria.
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Affiliation(s)
- German Pozdeev
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Aalap Mogre
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
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11
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Samuels DS, Lybecker MC, Yang XF, Ouyang Z, Bourret TJ, Boyle WK, Stevenson B, Drecktrah D, Caimano MJ. Gene Regulation and Transcriptomics. Curr Issues Mol Biol 2020; 42:223-266. [PMID: 33300497 DOI: 10.21775/cimb.042.223] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Borrelia (Borreliella) burgdorferi, along with closely related species, is the etiologic agent of Lyme disease. The spirochete subsists in an enzootic cycle that encompasses acquisition from a vertebrate host to a tick vector and transmission from a tick vector to a vertebrate host. To adapt to its environment and persist in each phase of its enzootic cycle, B. burgdorferi wields three systems to regulate the expression of genes: the RpoN-RpoS alternative sigma factor cascade, the Hk1/Rrp1 two-component system and its product c-di-GMP, and the stringent response mediated by RelBbu and DksA. These regulatory systems respond to enzootic phase-specific signals and are controlled or fine- tuned by transcription factors, including BosR and BadR, as well as small RNAs, including DsrABb and Bb6S RNA. In addition, several other DNA-binding and RNA-binding proteins have been identified, although their functions have not all been defined. Global changes in gene expression revealed by high-throughput transcriptomic studies have elucidated various regulons, albeit technical obstacles have mostly limited this experimental approach to cultivated spirochetes. Regardless, we know that the spirochete, which carries a relatively small genome, regulates the expression of a considerable number of genes required for the transitions between the tick vector and the vertebrate host as well as the adaptation to each.
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Affiliation(s)
- D Scott Samuels
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Meghan C Lybecker
- Department of Biology, University of Colorado, Colorado Springs, CO 80918, USA
| | - X Frank Yang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Zhiming Ouyang
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Travis J Bourret
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - William K Boyle
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - Brian Stevenson
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky School of Medicine, Lexington, KY 40536, USA
| | - Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Melissa J Caimano
- Departments of Medicine, Pediatrics, and Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA
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12
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Adamus-Białek W, Wawszczak M, Arabski M, Majchrzak M, Gulba M, Jarych D, Parniewski P, Głuszek S. Ciprofloxacin, amoxicillin, and aminoglycosides stimulate genetic and phenotypic changes in uropathogenic Escherichia coli strains. Virulence 2020; 10:260-276. [PMID: 30938219 PMCID: PMC6527016 DOI: 10.1080/21505594.2019.1596507] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Antibiotic therapy and its consequences in bacterial and human aspects are widely investigated. Despite this, the emergence of new multidrug resistant bacteria is still a current problem. The scope of our work included the observation of changes among uropathogenic Escherichia coli strains after the treatment with a subinhibitory concentration of different antibiotics. The sensitive strains with or without virulence factors were incubated with amoxicillin, ciprofloxacin, gentamycin, or tobramycin. After each passage, the E. coli derivatives were compared to their wild types based on their susceptibility profiles, virulence genes, biofilm formations and the fingerprint profiles of PCR products amplified with using the (N)(6)(CGG)(4) primer. It turned out that antibiotics caused significant changes in the repertoire of bacterial virulence and biofilm formation, corresponding to acquired cross-resistance. The genomic changes among the studied bacteria were reflected in the changed profiles of the CGG-PCR products. In conclusion, the inappropriate application of antibiotics may cause a rapid rise of Multidrug Resistant (MDR) strains and give bacteria a chance to modulate their own pathogenicity. This phenomenon has been easily observed among uropathogenic E. coli strains and it is one of the main reasons for recurrent infections of the urinary tract.
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Affiliation(s)
- Wioletta Adamus-Białek
- a Department of Surgery and Surgical Nursery with Laboratory of Genetics, Faculty of Medicine and Health Sciences , Jan Kochanowski University , Kielce , Poland
| | - Monika Wawszczak
- a Department of Surgery and Surgical Nursery with Laboratory of Genetics, Faculty of Medicine and Health Sciences , Jan Kochanowski University , Kielce , Poland
| | - Michał Arabski
- b Department of Biochemistry & Genetics , Jan Kochanowski University , Kielce , Poland
| | - Michał Majchrzak
- a Department of Surgery and Surgical Nursery with Laboratory of Genetics, Faculty of Medicine and Health Sciences , Jan Kochanowski University , Kielce , Poland
| | - Martyna Gulba
- a Department of Surgery and Surgical Nursery with Laboratory of Genetics, Faculty of Medicine and Health Sciences , Jan Kochanowski University , Kielce , Poland
| | - Dariusz Jarych
- c Institute of Medical Biology, Polish Academy of Sciences , Łódź , Poland
| | - Paweł Parniewski
- c Institute of Medical Biology, Polish Academy of Sciences , Łódź , Poland
| | - Stanisław Głuszek
- a Department of Surgery and Surgical Nursery with Laboratory of Genetics, Faculty of Medicine and Health Sciences , Jan Kochanowski University , Kielce , Poland
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13
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Genome-scale exploration of transcriptional regulation in the nisin Z producer Lactococcus lactis subsp. lactis IO-1. Sci Rep 2020; 10:3787. [PMID: 32123183 PMCID: PMC7051946 DOI: 10.1038/s41598-020-59731-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 01/13/2020] [Indexed: 02/06/2023] Open
Abstract
Transcription is of the most crucial steps of gene expression in bacteria, whose regulation guarantees the bacteria's ability to adapt to varying environmental conditions. Discovering the molecular basis and genomic principles of the transcriptional regulation is thus one of the most important tasks in cellular and molecular biology. Here, a comprehensive phylogenetic footprinting framework was implemented to predict maximal regulons of Lactococcus lactis subsp. lactis IO-1, a lactic acid bacterium known for its high potentials in nisin Z production as well as efficient xylose consumption which have made it a promising biotechnological strain. A total set of 321 regulons covering more than 90% of all the bacterium's operons have been elucidated and validated according to available data. Multiple novel biologically-relevant members were introduced amongst which arsC, mtlA and mtl operon for BusR, MtlR and XylR regulons can be named, respectively. Moreover, the effect of riboflavin on nisin biosynthesis was assessed in vitro and a negative correlation was observed. It is believed that understandings from such networks not only can be useful for studying transcriptional regulatory potentials of the target organism but also can be implemented in biotechnology to rationally design favorable production conditions.
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14
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Stratakos AC, Ijaz UZ, Ward P, Linton M, Kelly C, Pinkerton L, Scates P, McBride J, Pet I, Criste A, Stef D, Couto JM, Sloan WT, Dorrell N, Wren BW, Stef L, Gundogdu O, Corcionivoschi N. In vitro and in vivo characterisation of Listeria monocytogenes outbreak isolates. Food Control 2020. [DOI: 10.1016/j.foodcont.2019.106784] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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15
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Sun Z, Cagliero C, Izard J, Chen Y, Zhou YN, Heinz WF, Schneider TD, Jin DJ. Density of σ70 promoter-like sites in the intergenic regions dictates the redistribution of RNA polymerase during osmotic stress in Escherichia coli. Nucleic Acids Res 2019; 47:3970-3985. [PMID: 30843055 DOI: 10.1093/nar/gkz159] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/26/2019] [Accepted: 03/01/2019] [Indexed: 11/14/2022] Open
Abstract
RNA polymerase (RNAP), the transcription machinery, shows dynamic binding across the genomic DNA under different growth conditions. The genomic features that selectively redistribute the limited RNAP molecules to dictate genome-wide transcription in response to environmental cues remain largely unknown. We chose the bacterial osmotic stress response model to determine genomic features that direct genome-wide redistribution of RNAP during the stress. Genomic mapping of RNAP and transcriptome profiles corresponding to the different temporal states after salt shock were determined. We found rapid redistribution of RNAP across the genome, primarily at σ70 promoters. Three subsets of genes exhibiting differential salt sensitivities were identified. Sequence analysis using an information-theory based σ70 model indicates that the intergenic regions of salt-responsive genes are enriched with a higher density of σ70 promoter-like sites than those of salt-sensitive genes. In addition, the density of promoter-like sites has a positive linear correlation with RNAP binding at different salt concentrations. The RNAP binding contributed by the non-initiating promoter-like sites is important for gene transcription at high salt concentration. Our study demonstrates that hyperdensity of σ70 promoter-like sites in the intergenic regions of salt-responsive genes drives the RNAP redistribution for reprograming the transcriptome to counter osmotic stress.
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Affiliation(s)
- Zhe Sun
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Cedric Cagliero
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Jerome Izard
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yixiong Chen
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yan Ning Zhou
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - William F Heinz
- Optical Microscopy and Analysis Laboratory, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD 21702, USA
| | - Thomas D Schneider
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Ding Jun Jin
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
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16
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Growth Phase-Dependent Chromosome Condensation and Heat-Stable Nucleoid-Structuring Protein Redistribution in Escherichia coli under Osmotic Stress. J Bacteriol 2019; 201:JB.00469-19. [PMID: 31481544 DOI: 10.1128/jb.00469-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 08/29/2019] [Indexed: 12/11/2022] Open
Abstract
The heat-stable nucleoid-structuring (H-NS) protein is a global transcriptional regulator implicated in coordinating the expression of over 200 genes in Escherichia coli, including many involved in adaptation to osmotic stress. We have applied superresolved microscopy to quantify the intracellular and spatial reorganization of H-NS in response to a rapid osmotic shift. We found that H-NS showed growth phase-dependent relocalization in response to hyperosmotic shock. In stationary phase, H-NS detached from a tightly compacted bacterial chromosome and was excluded from the nucleoid volume over an extended period of time. This behavior was absent during rapid growth but was induced by exposing the osmotically stressed culture to a DNA gyrase inhibitor, coumermycin. This chromosomal compaction/H-NS exclusion phenomenon occurred in the presence of either potassium or sodium ions and was independent of the presence of stress-responsive sigma factor σS and of the H-NS paralog StpA.IMPORTANCE The heat-stable nucleoid-structuring (H-NS) protein coordinates the expression of over 200 genes in E. coli, with a large number involved in both bacterial virulence and drug resistance. We report on the novel observation of a dynamic compaction of the bacterial chromosome in response to exposure to high levels of salt. This stress response results in the detachment of H-NS proteins and their subsequent expulsion to the periphery of the cells. We found that this behavior is related to mechanical properties of the bacterial chromosome, in particular, to how tightly twisted and coiled is the chromosomal DNA. This behavior might act as a biomechanical response to stress that coordinates the expression of genes involved in adapting bacteria to a salty environment.
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17
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Dorman CJ, Ní Bhriain N. CRISPR-Cas, DNA Supercoiling, and Nucleoid-Associated Proteins. Trends Microbiol 2019; 28:19-27. [PMID: 31519332 DOI: 10.1016/j.tim.2019.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 08/02/2019] [Accepted: 08/08/2019] [Indexed: 12/11/2022]
Abstract
In this opinion article we highlight links between the H-NS nucleoid-associated protein, variable DNA topology, the regulation of CRISPR-cas locus expression, CRISPR-Cas activity, and the recruitment of novel genetic information by the CRISPR array. We propose that the requirement that the invading mobile genetic element be negatively supercoiled limits effective CRISPR action to a window in the bacterial growth cycle when DNA topology is optimal, and that this same window is used for the efficient integration of new spacer sequences at the CRISPR array. H-NS silences CRISPR promoters, and we propose that antagonists of H-NS, such as the LeuO transcription factor, provide a basis for a stochastic genetic switch that acts at random in each cell in the bacterial population. In addition, we wish to propose a mechanism by which mobile genetic elements can suppress CRISPR-cas transcription using H-NS homologues. Although the individual components of this network are known, we propose a new model in which they are integrated and linked to the physiological state of the bacterium. The model provides a basis for cell-to-cell variation in the expression and performance of CRISPR systems in bacterial populations.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Trinity College Dublin, Dublin 2, Ireland.
| | - Niamh Ní Bhriain
- Department of Microbiology, Trinity College Dublin, Dublin 2, Ireland
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18
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Martis B S, Forquet R, Reverchon S, Nasser W, Meyer S. DNA Supercoiling: an Ancestral Regulator of Gene Expression in Pathogenic Bacteria? Comput Struct Biotechnol J 2019; 17:1047-1055. [PMID: 31452857 PMCID: PMC6700405 DOI: 10.1016/j.csbj.2019.07.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/17/2019] [Accepted: 07/24/2019] [Indexed: 12/28/2022] Open
Abstract
DNA supercoiling acts as a global and ancestral regulator of bacterial gene expression. In this review, we advocate that it plays a pivotal role in host-pathogen interactions by transducing environmental signals to the bacterial chromosome and coordinating its transcriptional response. We present available evidence that DNA supercoiling is modulated by environmental stress conditions relevant to the infection process according to ancestral mechanisms, in zoopathogens as well as phytopathogens. We review the results of transcriptomics studies obtained in widely distant bacterial species, showing that such structural transitions of the chromosome are associated to a complex transcriptional response affecting a large fraction of the genome. Mechanisms and computational models of the transcriptional regulation by DNA supercoiling are then discussed, involving both basal interactions of RNA Polymerase with promoter DNA, and more specific interactions with regulatory proteins. A final part is specifically focused on the regulation of virulence genes within pathogenicity islands of several pathogenic bacterial species.
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Affiliation(s)
- Shiny Martis B
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Raphaël Forquet
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Sylvie Reverchon
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - William Nasser
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Sam Meyer
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
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19
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Dorman CJ. DNA supercoiling and transcription in bacteria: a two-way street. BMC Mol Cell Biol 2019; 20:26. [PMID: 31319794 PMCID: PMC6639932 DOI: 10.1186/s12860-019-0211-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/09/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The processes of DNA supercoiling and transcription are interdependent because the movement of a transcription elongation complex simultaneously induces under- and overwinding of the DNA duplex and because the initiation, elongation and termination steps of transcription are all sensitive to the topological state of the DNA. RESULTS Policing of the local and global supercoiling of DNA by topoisomerases helps to sustain the major DNA-based transactions by eliminating barriers to the movement of transcription complexes and replisomes. Recent data from whole-genome and single-molecule studies have provided new insights into how interactions between transcription and the supercoiling of DNA influence the architecture of the chromosome and how they create cell-to-cell diversity at the level of gene expression through transcription bursting. CONCLUSIONS These insights into fundamental molecular processes reveal mechanisms by which bacteria can prevail in unpredictable and often hostile environments by becoming unpredictable themselves.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
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20
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Szafran MJ, Gongerowska M, Małecki T, Elliot M, Jakimowicz D. Transcriptional Response of Streptomyces coelicolor to Rapid Chromosome Relaxation or Long-Term Supercoiling Imbalance. Front Microbiol 2019; 10:1605. [PMID: 31354687 PMCID: PMC6637917 DOI: 10.3389/fmicb.2019.01605] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/26/2019] [Indexed: 12/14/2022] Open
Abstract
Negative DNA supercoiling allows chromosome condensation and facilitates DNA unwinding, which is required for the occurrence of DNA transaction processes, i.e., DNA replication, transcription and recombination. In bacteria, changes in chromosome supercoiling impact global gene expression; however, the limited studies on the global transcriptional response have focused mostly on pathogenic species and have reported various fractions of affected genes. Furthermore, the transcriptional response to long-term supercoiling imbalance is still poorly understood. Here, we address the transcriptional response to both novobiocin-induced rapid chromosome relaxation or long-term topological imbalance, both increased and decreased supercoiling, in environmental antibiotic-producing bacteria belonging to the Streptomyces genus. During the Streptomyces complex developmental cycle, multiple copies of GC-rich linear chromosomes present in hyphal cells undergo profound topological changes, from being loosely condensed in vegetative hyphae, to being highly compacted in spores. Moreover, changes in chromosomal supercoiling have been suggested to be associated with the control of antibiotic production and environmental stress response. Remarkably, in S. coelicolor, a model Streptomyces species, topoisomerase I (TopA) is solely responsible for the removal of negative DNA supercoils. Using a S. coelicolor strain in which topA transcription is under the control of an inducible promoter, we identified genes involved in the transcriptional response to long-term supercoiling imbalance. The affected genes are preferentially organized in several clusters, and a supercoiling-hypersensitive cluster (SHC) was found to be located in the core of the S. coelicolor chromosome. The transcripts affected by long-term topological imbalance encompassed genes encoding nucleoid-associated proteins, DNA repair proteins and transcriptional regulators, including multiple developmental regulators. Moreover, using a gyrase inhibitor, we identified those genes that were directly affected by novobiocin, and found this was correlated with increased AT content in their promoter regions. In contrast to the genes affected by long-term supercoiling changes, among the novobiocin-sensitive genes, a significant fraction encoded for proteins associated with membrane transport or secondary metabolite synthesis. Collectively, our results show that long-term supercoiling imbalance globally regulates gene transcription and has the potential to impact development, secondary metabolism and DNA repair, amongst others.
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Affiliation(s)
- Marcin Jan Szafran
- Laboratory of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Martyna Gongerowska
- Laboratory of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Tomasz Małecki
- Laboratory of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Marie Elliot
- Department of Biology, M.G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Dagmara Jakimowicz
- Laboratory of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
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21
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Feng X, He C, Jiao L, Liang X, Zhao R, Guo Y. Analysis of differential expression proteins reveals the key pathway in response to heat stress in Alicyclobacillus acidoterrestris DSM 3922T. Food Microbiol 2019; 80:77-84. [DOI: 10.1016/j.fm.2019.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 11/12/2018] [Accepted: 01/06/2019] [Indexed: 11/27/2022]
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22
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Decreased Effective Macromolecular Crowding in Escherichia coli Adapted to Hyperosmotic Stress. J Bacteriol 2019; 201:JB.00708-18. [PMID: 30833357 PMCID: PMC6482933 DOI: 10.1128/jb.00708-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/21/2019] [Indexed: 11/20/2022] Open
Abstract
Bacteria adapt to ever-changing environmental conditions such as osmotic stress and energy limitation. It is not well understood how biomolecules reorganize themselves inside Escherichia coli under these conditions. An altered biochemical organization would affect macromolecular crowding, which could influence reaction rates and diffusion of macromolecules. In cells adapted to osmotic upshift, protein diffusion is indeed faster than expected on the basis of the biopolymer volume fraction. We now probe the effects of macromolecular crowding in cells adapted to osmotic stress or depleted in metabolic energy with a genetically encoded fluorescence-based probe. We find that the effective macromolecular crowding in adapted and energy-depleted cells is lower than in unstressed cells, indicating major alterations in the biochemical organization of the cytoplasm. Escherichia coli adapts to changing environmental osmolality to survive and maintain growth. It has been shown that the diffusion of green fluorescent protein (GFP) in cells adapted to osmotic upshifts is higher than expected from the increase in biopolymer volume fraction. To better understand the physicochemical state of the cytoplasm in adapted cells, we now follow the macromolecular crowding during adaptation with fluorescence resonance energy transfer (FRET)-based sensors. We apply an osmotic upshift and find that after an initial increase, the apparent crowding decreases over the course of hours to arrive at a value lower than that before the osmotic upshift. Crowding relates to cell volume until cell division ensues, after which a transition in the biochemical organization occurs. Analysis of single cells by microfluidics shows that changes in cell volume, elongation, and division are most likely not the cause for the transition in organization. We further show that the decrease in apparent crowding upon adaptation is similar to the apparent crowding in energy-depleted cells. Based on our findings in combination with literature data, we suggest that adapted cells have indeed an altered biochemical organization of the cytoplasm, possibly due to different effective particle size distributions and concomitant nanoscale heterogeneity. This could potentially be a general response to accommodate higher biopolymer fractions yet retaining crowding homeostasis, and it could apply to other species or conditions as well. IMPORTANCE Bacteria adapt to ever-changing environmental conditions such as osmotic stress and energy limitation. It is not well understood how biomolecules reorganize themselves inside Escherichia coli under these conditions. An altered biochemical organization would affect macromolecular crowding, which could influence reaction rates and diffusion of macromolecules. In cells adapted to osmotic upshift, protein diffusion is indeed faster than expected on the basis of the biopolymer volume fraction. We now probe the effects of macromolecular crowding in cells adapted to osmotic stress or depleted in metabolic energy with a genetically encoded fluorescence-based probe. We find that the effective macromolecular crowding in adapted and energy-depleted cells is lower than in unstressed cells, indicating major alterations in the biochemical organization of the cytoplasm.
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23
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Chernov VM, Chernova OA, Mouzykantov AA, Lopukhov LL, Aminov RI. Omics of antimicrobials and antimicrobial resistance. Expert Opin Drug Discov 2019; 14:455-468. [DOI: 10.1080/17460441.2019.1588880] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Vladislav M. Chernov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Kazan, Russian Federation
- Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russian Federation
| | - Olga A. Chernova
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Kazan, Russian Federation
- Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russian Federation
| | - Alexey A. Mouzykantov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Kazan, Russian Federation
- Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russian Federation
| | - Leonid L. Lopukhov
- Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russian Federation
| | - Rustam I. Aminov
- Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russian Federation
- Applied Health Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
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24
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Jousset AB, Rosinski-Chupin I, Takissian J, Glaser P, Bonnin RA, Naas T. Transcriptional Landscape of a bla KPC-2 Plasmid and Response to Imipenem Exposure in Escherichia coli TOP10. Front Microbiol 2018; 9:2929. [PMID: 30559731 PMCID: PMC6286996 DOI: 10.3389/fmicb.2018.02929] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/14/2018] [Indexed: 12/15/2022] Open
Abstract
The diffusion of KPC-2 carbapenemase is closely related to the spread of Klebsiella pneumoniae of the clonal-group 258 and linked to IncFIIK plasmids. Little is known about the biology of multi-drug resistant plasmids and the reasons of their successful dissemination. Using E. coli TOP10 strain harboring a multi-replicon IncFIIK-IncFIB blaKPC−2-gene carrying plasmid pBIC1a from K. pneumoniae ST-258 clinical isolate BIC-1, we aimed to identify basal gene expression and the effects of imipenem exposure using whole transcriptome approach by RNA sequencing (RNA-Seq). Independently of the antibiotic pressure, most of the plasmid-backbone genes were expressed at low levels. The most expressed pBIC1a genes were involved in antibiotic resistance (blaKPC−2, blaTEM and aph(3′)-I), in plasmid replication and conjugation, or associated to mobile elements. After antibiotic exposure, 34% of E. coli (pBIC1a) genome was differentially expressed. Induction of oxidative stress response was evidenced, with numerous upregulated genes of the SoxRS/OxyR oxydative stress regulons, the Fur regulon (for iron uptake machinery), and IscR regulon (for iron sulfur cluster synthesis). Nine genes carried by pBIC1a were up-regulated, including the murein DD-endopeptidase mepM and the copper resistance operon. Despite the presence of a carbapenemase, we observed a major impact on E. coli (pBIC1a) whole transcriptome after imipenem exposure, but no effect on the level of transcription of antimicrobial resistance genes. We describe adaptive responses of E. coli to imipenem-induced stress, and identified plasmid-encoded genes that could be involved in resistance to stressful environments.
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Affiliation(s)
- Agnès B Jousset
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Isabelle Rosinski-Chupin
- Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France.,CNRS, UMRS 3525, Paris, France
| | - Julie Takissian
- EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Philippe Glaser
- Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France.,CNRS, UMRS 3525, Paris, France
| | - Rémy A Bonnin
- Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Thierry Naas
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
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25
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Ng TW, Ip M, Chao CYH, Tang JW, Lai KP, Fu SC, Leung WT, Lai KM. Differential gene expression in Escherichia coli during aerosolization from liquid suspension. Appl Microbiol Biotechnol 2018; 102:6257-6267. [DOI: 10.1007/s00253-018-9083-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/29/2018] [Accepted: 05/08/2018] [Indexed: 10/14/2022]
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26
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Basu A, Hobson M, Lebel P, Fernandes LE, Tretter EM, Berger JM, Bryant Z. Dynamic coupling between conformations and nucleotide states in DNA gyrase. Nat Chem Biol 2018; 14:565-574. [PMID: 29662209 PMCID: PMC10121156 DOI: 10.1038/s41589-018-0037-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 02/21/2018] [Indexed: 11/09/2022]
Abstract
Gyrase is an essential bacterial molecular motor that supercoils DNA using a conformational cycle in which chiral wrapping of > 100 base pairs confers directionality on topoisomerization. To understand the mechanism of this nucleoprotein machine, global structural transitions must be mapped onto the nucleotide cycle of ATP binding, hydrolysis and product release. Here we investigate coupling mechanisms using single-molecule tracking of DNA rotation and contraction during Escherichia coli gyrase activity under varying nucleotide conditions. We find that ADP must be exchanged for ATP to drive the rate-limiting remodeling transition that generates the chiral wrap. ATP hydrolysis accelerates subsequent duplex strand passage and is required for resetting the enzyme and recapturing transiently released DNA. Our measurements suggest how gyrase coordinates DNA rearrangements with the dynamics of its ATP-driven protein gate, how the motor minimizes futile cycles of ATP hydrolysis and how gyrase may respond to changing cellular energy levels to link gene expression with metabolism.
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Affiliation(s)
- Aakash Basu
- Department of Applied Physics, Stanford University, Stanford, CA, USA.,Department of Bioengineering, Stanford University, Stanford, CA, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Matthew Hobson
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Program in Molecular Biophysics, Johns Hopkins University, Baltimore, MD, USA
| | - Paul Lebel
- Department of Applied Physics, Stanford University, Stanford, CA, USA.,Department of Bioengineering, Stanford University, Stanford, CA, USA.,Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Louis E Fernandes
- Department of Bioengineering, Stanford University, Stanford, CA, USA.,Program in Biophysics, Stanford University, Stanford, CA, USA.,Tempus, Inc., Chicago, IL, USA
| | - Elsa M Tretter
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.,Nurix Inc., San Francisco, CA, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Zev Bryant
- Department of Bioengineering, Stanford University, Stanford, CA, USA. .,Department of Structural Biology, Stanford University Medical Center, Stanford, CA, USA.
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27
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Modulation of Global Transcriptional Regulatory Networks as a Strategy for Increasing Kanamycin Resistance of the Translational Elongation Factor-G Mutants in Escherichia coli. G3-GENES GENOMES GENETICS 2017; 7:3955-3966. [PMID: 29046437 PMCID: PMC5714492 DOI: 10.1534/g3.117.300284] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Evolve and resequence experiments have provided us a tool to understand bacterial adaptation to antibiotics. In our previous work, we used short-term evolution to isolate mutants resistant to the ribosome targeting antibiotic kanamycin, and reported that Escherichia coli develops low cost resistance to kanamycin via different point mutations in the translation Elongation Factor-G (EF-G). Furthermore, we had shown that the resistance of EF-G mutants could be increased by second site mutations in the genes rpoD/cpxA/topA/cyaA Mutations in three of these genes had been discovered in earlier screens for aminoglycoside resistance. In this work, we expand our understanding of these second site mutations, the goal being to understand how these mutations affect the activities of the mutated gene products to confer resistance. We show that the mutation in cpxA most likely results in an active Cpx stress response. Further evolution of an EF-G mutant in a higher concentration of kanamycin than what was used in our previous experiments identified the cpxA locus as a primary target for a significant increase in resistance. The mutation in cyaA results in a loss of catalytic activity and probably results in resistance via altered CRP function. Despite a reduction in cAMP levels, the CyaAN600Y mutant has a transcriptome indicative of increased CRP activity, pointing to an unknown role for CyaA and / or cAMP in gene expression. From the transcriptomes of double and single mutants, we describe the epistasis between the mutation in EF-G and these second site mutations. We show that the large scale transcriptomic changes in the topoisomerase I (FusAA608E-TopAS180L) mutant likely result from increased negative supercoiling in the cell. Finally, genes with known roles in aminoglycoside resistance were present among the misregulated genes in the mutants.
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Zhou Q, Zhou YN, Jin DJ, Tse-Dinh YC. Deacetylation of topoisomerase I is an important physiological function of E. coli CobB. Nucleic Acids Res 2017; 45:5349-5358. [PMID: 28398568 PMCID: PMC5605244 DOI: 10.1093/nar/gkx250] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 04/03/2017] [Indexed: 01/08/2023] Open
Abstract
Escherichia coli topoisomerase I (TopA), a regulator of global and local DNA supercoiling, is modified by Nε-Lysine acetylation. The NAD+-dependent protein deacetylase CobB can reverse both enzymatic and non-enzymatic lysine acetylation modification in E. coli. Here, we show that the absence of CobB in a ΔcobB mutant reduces intracellular TopA catalytic activity and increases negative DNA supercoiling. TopA expression level is elevated as topA transcription responds to the increased negative supercoiling. The slow growth phenotype of the ΔcobB mutant can be partially compensated by further increase of intracellular TopA level via overexpression of recombinant TopA. The relaxation activity of purified TopA is decreased by in vitro non-enzymatic acetyl phosphate mediated lysine acetylation, and the presence of purified CobB protects TopA from inactivation by such non-enzymatic acetylation. The specific activity of TopA expressed from His-tagged fusion construct in the chromosome is inversely proportional to the degree of in vivo lysine acetylation during growth transition and growth arrest. These findings demonstrate that E. coli TopA catalytic activity can be modulated by lysine acetylation–deacetylation, and prevention of TopA inactivation from excess lysine acetylation and consequent increase in negative DNA supercoiling is an important physiological function of the CobB protein deacetylase.
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Affiliation(s)
- Qingxuan Zhou
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.,Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Yan Ning Zhou
- Transcription Control Section, RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Ding Jun Jin
- Transcription Control Section, RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yuk-Ching Tse-Dinh
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.,Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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29
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Correia S, Hébraud M, Chafsey I, Chambon C, Viala D, Torres C, Caniça M, Capelo JL, Poeta P, Igrejas G. Subproteomic signature comparison of in vitro selected fluoroquinolone resistance and ciprofloxacin stress in Salmonella Typhimurium DT104B. Expert Rev Proteomics 2017; 14:941-961. [PMID: 28871888 DOI: 10.1080/14789450.2017.1375856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Fluoroquinolone resistance in nontyphoidal Salmonella is a situation of serious and international concern, particularly in S. Typhimurium DT104B multiresistant strains. Although known to be multifactorial, fluoroquinolone resistance is still far from a complete understanding. METHODS Subproteome changes between an experimentally selected fluoroquinolone-resistant strain (Se6-M) and its parent strain (Se6), and also in Se6-M under ciprofloxacin (CIP) stress, were evaluated in order to give new insights into the mechanisms involved. Proteomes were compared at the intracellular and membrane levels by a 2-DE~LC-MS/MS and a shotgun LC-MS/MS approach, respectively. RESULTS In total, 35 differentially abundant proteins were identified when comparing Se6 with Se6-M (25 more abundant in Se6 and 10 more abundant in Se6-M) and 82 were identified between Se6-M and Se6-M+CIP (51 more abundant in Se6-M and 31 more abundant under ciprofloxacin stress). CONCLUSION Several proteins with known and possible roles in quinolone resistance were identified which provide important information about mechanism-related differential protein expression, supporting the current knowledge and also leading to new testable hypotheses on the mechanism of action of fluoroquinolone drugs.
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Affiliation(s)
- Susana Correia
- a Functional Genomics and Proteomics Unit , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,b Department of Genetics and Biotechnology , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,c Veterinary Science Department , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,d UCIBIO-REQUIMTE, Faculty of Science and Technology , Nova University of Lisbon , Caparica , Portugal
| | - Michel Hébraud
- e UR454 Microbiology , Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes , site de Theix , Saint-Genès Champanelle , France.,f Plate-Forme d'Exploration du Métabolisme composante protéomique, UR370 QuaPA , Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes , site de Theix , Saint-Genès Champanelle , France
| | - Ingrid Chafsey
- e UR454 Microbiology , Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes , site de Theix , Saint-Genès Champanelle , France
| | - Christophe Chambon
- f Plate-Forme d'Exploration du Métabolisme composante protéomique, UR370 QuaPA , Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes , site de Theix , Saint-Genès Champanelle , France
| | - Didier Viala
- f Plate-Forme d'Exploration du Métabolisme composante protéomique, UR370 QuaPA , Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes , site de Theix , Saint-Genès Champanelle , France
| | - Carmen Torres
- g Área de Bioquímica y Biología Molecular , Universidad de La Rioja , Logroño , Spain
| | - Manuela Caniça
- h National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections (NRL-AMR-HAI), Department of Infectious Diseases , National Health Institute Doutor Ricardo Jorge (INSA) , Lisbon , Portugal
| | - José Luis Capelo
- d UCIBIO-REQUIMTE, Faculty of Science and Technology , Nova University of Lisbon , Caparica , Portugal.,i Faculty of Sciences and Technology , ProteoMass Scientific Society , Caparica , Portugal
| | - Patrícia Poeta
- c Veterinary Science Department , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,d UCIBIO-REQUIMTE, Faculty of Science and Technology , Nova University of Lisbon , Caparica , Portugal
| | - Gilberto Igrejas
- a Functional Genomics and Proteomics Unit , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,b Department of Genetics and Biotechnology , University of Trás-os-Montes and Alto Douro , Vila Real , Portugal.,d UCIBIO-REQUIMTE, Faculty of Science and Technology , Nova University of Lisbon , Caparica , Portugal
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30
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Hoffmann T, Bleisteiner M, Sappa PK, Steil L, Mäder U, Völker U, Bremer E. Synthesis of the compatible solute proline by Bacillus subtilis: point mutations rendering the osmotically controlled proHJ promoter hyperactive. Environ Microbiol 2017; 19:3700-3720. [PMID: 28752945 DOI: 10.1111/1462-2920.13870] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/09/2017] [Accepted: 07/24/2017] [Indexed: 01/29/2023]
Abstract
The ProJ and ProH enzymes of Bacillus subtilis catalyse together with ProA (ProJ-ProA-ProH), osmostress-adaptive synthesis of the compatible solute proline. The proA-encoded gamma-glutamyl phosphate reductase is also used for anabolic proline synthesis (ProB-ProA-ProI). Transcription of the proHJ operon is osmotically inducible whereas that of the proBA operon is not. Targeted and quantitative proteome analysis revealed that the amount of ProA is not limiting for the interconnected anabolic and osmostress-responsive proline production routes. A key player for enhanced osmostress-adaptive proline production is the osmotically regulated proHJ promoter. We used site-directed mutagenesis to study the salient features of this stress-responsive promoter. Two important features were identified: (i) deviations of the proHJ promoter from the consensus sequence of SigA-type promoters serve to keep transcription low under non-inducing growth conditions, while still allowing a finely tuned induction of transcriptional activity when the external osmolarity is increased and (ii) a suboptimal spacer length for SigA-type promoters of either 16-bp (the natural proHJ promoter), or 18-bp (a synthetic promoter variant) is strictly required to allow regulation of promoter activity in proportion to the external salinity. Collectively, our data suggest that changes in the local DNA structure at the proHJ promoter are important determinants for osmostress-inducibility of transcription.
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Affiliation(s)
- Tamara Hoffmann
- Department of Biology, Laboratory for Microbiology, Philipps-University Marburg, Karl-von-Frisch-Str. 8, Marburg D-35043, Germany
| | - Monika Bleisteiner
- Department of Biology, Laboratory for Microbiology, Philipps-University Marburg, Karl-von-Frisch-Str. 8, Marburg D-35043, Germany
| | - Praveen Kumar Sappa
- Interfaculty Institute of Genetics and Functional Genomics, Department Functional Genomics, University Medicine Greifswald, Friedrich-Ludwig-Jahn-Str. 15, Greifswald D-17475, Germany
| | - Leif Steil
- Interfaculty Institute of Genetics and Functional Genomics, Department Functional Genomics, University Medicine Greifswald, Friedrich-Ludwig-Jahn-Str. 15, Greifswald D-17475, Germany
| | - Ulrike Mäder
- Interfaculty Institute of Genetics and Functional Genomics, Department Functional Genomics, University Medicine Greifswald, Friedrich-Ludwig-Jahn-Str. 15, Greifswald D-17475, Germany
| | - Uwe Völker
- Interfaculty Institute of Genetics and Functional Genomics, Department Functional Genomics, University Medicine Greifswald, Friedrich-Ludwig-Jahn-Str. 15, Greifswald D-17475, Germany
| | - Erhard Bremer
- Department of Biology, Laboratory for Microbiology, Philipps-University Marburg, Karl-von-Frisch-Str. 8, Marburg D-35043, Germany
- LOEWE-Center for Synthetic Microbiology, Philipps-University Marburg, Hans-Meerweinstr. 6, Marburg D-35043, Germany
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31
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Xiao M, Zhu X, Xu H, Tang J, Liu R, Bi C, Fan F, Zhang X. A novel point mutation in RpoB improves osmotolerance and succinic acid production in Escherichia coli. BMC Biotechnol 2017; 17:10. [PMID: 28193207 PMCID: PMC5307762 DOI: 10.1186/s12896-017-0337-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 02/10/2017] [Indexed: 11/29/2022] Open
Abstract
Background Escherichia coli suffer from osmotic stress during succinic acid (SA) production, which reduces the performance of this microbial factory. Results Here, we report that a point mutation leading to a single amino acid change (D654Y) within the β-subunit of DNA-dependent RNA polymerase (RpoB) significantly improved the osmotolerance of E. coli. Importation of the D654Y mutation of RpoB into the parental strain, Suc-T110, increased cell growth and SA production by more than 40% compared to that of the control under high glucose osmolality. The transcriptome profile, determined by RNA-sequencing, showed two distinct stress responses elicited by the mutated RpoB that counterbalanced the osmotic stress. Under non-stressed conditions, genes involved in the synthesis and transport of compatible solutes such as glycine-betaine, glutamate or proline were upregulated even without osmotic stimulation, suggesting a “pre-defense” mechanism maybe formed in the rpoB mutant. Under osmotic stressed conditions, genes encoding diverse sugar transporters, which should be down-regulated in the presence of high osmotic pressure, were derepressed in the rpoB mutant. Additional genetic experiments showed that enhancing the expression of the mal regulon, especially for genes that encode the glycoporin LamB and maltose transporter, contributed to the osmotolerance phenotype. Conclusions The D654Y single amino acid substitution in RpoB rendered E. coli cells resistant to osmotic stress, probably due to improved cell growth and viability via enhanced sugar uptake under stressed conditions, and activated a potential “pre-defense” mechanism under non-stressed conditions. The findings of this work will be useful for bacterial host improvement to enhance its resistance to osmotic stress and facilitate bio-based organic acids production. Electronic supplementary material The online version of this article (doi:10.1186/s12896-017-0337-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mengyong Xiao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xinna Zhu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Hongtao Xu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Jinlei Tang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Ru Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Changhao Bi
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Feiyu Fan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China.
| | - Xueli Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Ave, Tianjin Airport Economic Park, Tianjin, 300308, China.
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32
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He G, Deng J, Wu C, Huang J. A partial proteome reference map of Tetragenococcus halophilus and comparative proteomic and physiological analysis under salt stress. RSC Adv 2017. [DOI: 10.1039/c6ra22521g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Tetragenococcus halophilus, a moderately halophilic Gram-positive lactic acid bacteria, was widely existed in many food fermentation systems, where salt stress is an environmental condition commonly encountered.
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Affiliation(s)
- Guiqiang He
- College of Light Industry, Textile & Food Engineering
- Sichuan University
- Chengdu 610065
- China
- Key Laboratory of Leather Chemistry and Engineering
| | - Jingcheng Deng
- College of Light Industry, Textile & Food Engineering
- Sichuan University
- Chengdu 610065
- China
- Key Laboratory of Leather Chemistry and Engineering
| | - Chongde Wu
- College of Light Industry, Textile & Food Engineering
- Sichuan University
- Chengdu 610065
- China
- Key Laboratory of Leather Chemistry and Engineering
| | - Jun Huang
- College of Light Industry, Textile & Food Engineering
- Sichuan University
- Chengdu 610065
- China
- Key Laboratory of Leather Chemistry and Engineering
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33
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Kasho K, Tanaka H, Sakai R, Katayama T. Cooperative DnaA Binding to the Negatively Supercoiled datA Locus Stimulates DnaA-ATP Hydrolysis. J Biol Chem 2016; 292:1251-1266. [PMID: 27941026 DOI: 10.1074/jbc.m116.762815] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 12/07/2016] [Indexed: 11/06/2022] Open
Abstract
Timely initiation of replication in Escherichia coli requires functional regulation of the replication initiator, ATP-DnaA. The cellular level of ATP-DnaA increases just before initiation, after which its level decreases through hydrolysis of DnaA-bound ATP, yielding initiation-inactive ADP-DnaA. Previously, we reported a novel DnaA-ATP hydrolysis system involving the chromosomal locus datA and named it datA-dependent DnaA-ATP hydrolysis (DDAH). The datA locus contains a binding site for a nucleoid-associating factor integration host factor (IHF) and a cluster of three known DnaA-binding sites, which are important for DDAH. However, the mechanisms underlying the formation and regulation of the datA-IHF·DnaA complex remain unclear. We now demonstrate that a novel DnaA box within datA is essential for ATP-DnaA complex formation and DnaA-ATP hydrolysis. Specific DnaA residues, which are important for interaction with bound ATP and for head-to-tail inter-DnaA interaction, were also required for ATP-DnaA-specific oligomer formation on datA Furthermore, we show that negative DNA supercoiling of datA stabilizes ATP-DnaA oligomers, and stimulates datA-IHF interaction and DnaA-ATP hydrolysis. Relaxation of DNA supercoiling by the addition of novobiocin, a DNA gyrase inhibitor, inhibits datA function in cells. On the basis of these results, we propose a mechanistic model of datA-IHF·DnaA complex formation and DNA supercoiling-dependent regulation for DDAH.
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Affiliation(s)
- Kazutoshi Kasho
- From the Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Hiroyuki Tanaka
- From the Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Ryuji Sakai
- From the Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Tsutomu Katayama
- From the Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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34
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Dorman CJ, Dorman MJ. DNA supercoiling is a fundamental regulatory principle in the control of bacterial gene expression. Biophys Rev 2016; 8:89-100. [PMID: 28510216 DOI: 10.1007/s12551-016-0238-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/01/2016] [Indexed: 11/28/2022] Open
Abstract
Although it has become routine to consider DNA in terms of its role as a carrier of genetic information, it is also an important contributor to the control of gene expression. This regulatory principle arises from its structural properties. DNA is maintained in an underwound state in most bacterial cells and this has important implications both for DNA storage in the nucleoid and for the expression of genetic information. Underwinding of the DNA through reduction in its linking number potentially imparts energy to the duplex that is available to drive DNA transactions, such as transcription, replication and recombination. The topological state of DNA also influences its affinity for some DNA binding proteins, especially in DNA sequences that have a high A + T base content. The underwinding of DNA by the ATP-dependent topoisomerase DNA gyrase creates a continuum between metabolic flux, DNA topology and gene expression that underpins the global response of the genome to changes in the intracellular and external environments. These connections describe a fundamental and generalised mechanism affecting global gene expression that underlies the specific control of transcription operating through conventional transcription factors. This mechanism also provides a basal level of control for genes acquired by horizontal DNA transfer, assisting microbial evolution, including the evolution of pathogenic bacteria.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
| | - Matthew J Dorman
- Department of Genetics, Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.,Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
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35
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Métris A, George SM, Ropers D. Piecewise linear approximations to model the dynamics of adaptation to osmotic stress by food-borne pathogens. Int J Food Microbiol 2016; 240:63-74. [PMID: 27377009 DOI: 10.1016/j.ijfoodmicro.2016.06.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 06/09/2016] [Accepted: 06/19/2016] [Indexed: 01/08/2023]
Abstract
Addition of salt to food is one of the most ancient and most common methods of food preservation. However, little is known of how bacterial cells adapt to such conditions. We propose to use piecewise linear approximations to model the regulatory adaptation of Escherichiacoli to osmotic stress. We apply the method to eight selected genes representing the functions known to be at play during osmotic adaptation. The network is centred on the general stress response factor, sigma S, and also includes a module representing the catabolic repressor CRP-cAMP. Glutamate, potassium and supercoiling are combined to represent the intracellular regulatory signal during osmotic stress induced by salt. The output is a module where growth is represented by the concentration of stable RNAs and the transcription of the osmotic gene osmY. The time course of gene expression of transport of osmoprotectant represented by the symporter proP and of the osmY is successfully reproduced by the network. The behaviour of the rpoS mutant predicted by the model is in agreement with experimental data. We discuss the application of the model to food-borne pathogens such as Salmonella; although the genes considered have orthologs, it seems that supercoiling is not regulated in the same way. The model is limited to a few selected genes, but the regulatory interactions are numerous and span different time scales. In addition, they seem to be condition specific: the links that are important during the transition from exponential to stationary phase are not all needed during osmotic stress. This model is one of the first steps towards modelling adaptation to stress in food safety and has scope to be extended to other genes and pathways, other stresses relevant to the food industry, and food-borne pathogens. The method offers a good compromise between systems of ordinary differential equations, which would be unmanageable because of the size of the system and for which insufficient data are available, and the more abstract Boolean methods.
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Affiliation(s)
- Aline Métris
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK.
| | - Susie M George
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK.
| | - Delphine Ropers
- Inria Grenoble - Rhône-Alpes Research Center, Saint Ismier, France.
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36
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DNA supercoiling is a fundamental regulatory principle in the control of bacterial gene expression. Biophys Rev 2016; 8:209-220. [PMID: 28510224 DOI: 10.1007/s12551-016-0205-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/01/2016] [Indexed: 12/27/2022] Open
Abstract
Although it has become routine to consider DNA in terms of its role as a carrier of genetic information, it is also an important contributor to the control of gene expression. This regulatory principle arises from its structural properties. DNA is maintained in an underwound state in most bacterial cells and this has important implications both for DNA storage in the nucleoid and for the expression of genetic information. Underwinding of the DNA through reduction in its linking number potentially imparts energy to the duplex that is available to drive DNA transactions, such as transcription, replication and recombination. The topological state of DNA also influences its affinity for some DNA binding proteins, especially in DNA sequences that have a high A + T base content. The underwinding of DNA by the ATP-dependent topoisomerase DNA gyrase creates a continuum between metabolic flux, DNA topology and gene expression that underpins the global response of the genome to changes in the intracellular and external environments. These connections describe a fundamental and generalised mechanism affecting global gene expression that underlies the specific control of transcription operating through conventional transcription factors. This mechanism also provides a basal level of control for genes acquired by horizontal DNA transfer, assisting microbial evolution, including the evolution of pathogenic bacteria.
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37
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WrpA Is an Atypical Flavodoxin Family Protein under Regulatory Control of the Brucella abortus General Stress Response System. J Bacteriol 2016; 198:1281-93. [PMID: 26858101 DOI: 10.1128/jb.00982-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/27/2016] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED The general stress response (GSR) system of the intracellular pathogen Brucella abortus controls the transcription of approximately 100 genes in response to a range of stress cues. The core genetic regulatory components of the GSR are required for B. abortus survival under nonoptimal growth conditions in vitro and for maintenance of chronic infection in an in vivo mouse model. The functions of the majority of the genes in the GSR transcriptional regulon remain undefined. bab1_1070 is among the most highly regulated genes in this regulon: its transcription is activated 20- to 30-fold by the GSR system under oxidative conditions in vitro. We have solved crystal structures of Bab1_1070 and demonstrate that it forms a homotetrameric complex that resembles those of WrbA-type NADH:quinone oxidoreductases, which are members of the flavodoxin protein family. However, B. abortus WrbA-related protein (WrpA) does not bind flavin cofactors with a high affinity and does not function as an NADH:quinone oxidoreductase in vitro. Soaking crystals with flavin mononucleotide (FMN) revealed a likely low-affinity binding site adjacent to the canonical WrbA flavin binding site. Deletion of wrpA (ΔwrpA) does not compromise cell survival under acute oxidative stress in vitro or attenuate infection in cell-based or mouse models. However, a ΔwrpA strain does elicit increased splenomegaly in a mouse model, suggesting that WrpA modulates B. abortus interaction with its mammalian host. Despite high structural homology with canonical WrbA proteins, we propose that B. abortus WrpA represents a functionally distinct member of the diverse flavodoxin family. IMPORTANCE Brucella abortus is an etiological agent of brucellosis, which is among the most common zoonotic diseases worldwide. The general stress response (GSR) regulatory system of B. abortus controls the transcription of approximately 100 genes and is required for maintenance of chronic infection in a murine model; the majority of GSR-regulated genes remain uncharacterized. We present in vitro and in vivo functional and structural analyses of WrpA, whose expression is strongly induced by GSR under oxidative conditions. Though WrpA is structurally related to NADH:quinone oxidoreductases, it does not bind redox cofactors in solution, nor does it exhibit oxidoreductase activity in vitro. However, WrpA does affect spleen inflammation in a murine infection model. Our data provide evidence that WrpA forms a new functional class of WrbA/flavodoxin family proteins.
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38
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Lal A, Dhar A, Trostel A, Kouzine F, Seshasayee ASN, Adhya S. Genome scale patterns of supercoiling in a bacterial chromosome. Nat Commun 2016; 7:11055. [PMID: 27025941 PMCID: PMC4820846 DOI: 10.1038/ncomms11055] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/16/2016] [Indexed: 11/09/2022] Open
Abstract
DNA in bacterial cells primarily exists in a negatively supercoiled state. The extent of supercoiling differs between regions of the chromosome, changes in response to external conditions and regulates gene expression. Here we report the use of trimethylpsoralen intercalation to map the extent of supercoiling across the Escherichia coli chromosome during exponential and stationary growth phases. We find that stationary phase E. coli cells display a gradient of negative supercoiling, with the terminus being more negatively supercoiled than the origin of replication, and that such a gradient is absent in exponentially growing cells. This stationary phase pattern is correlated with the binding of the nucleoid-associated protein HU, and we show that it is lost in an HU deletion strain. We suggest that HU establishes higher supercoiling near the terminus of the chromosome during stationary phase, whereas during exponential growth DNA gyrase and/or transcription equalizes supercoiling across the chromosome. Bacterial DNA primarily exists in a negatively supercoiled or under-wound state. Here, by mapping the supercoiling state, the authors show that there is a gradient of supercoiling across the bacterial chromosome with the terminus being more negatively supercoiled than the origin.
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Affiliation(s)
- Avantika Lal
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, Karnataka, India
| | - Amlanjyoti Dhar
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA
| | - Andrei Trostel
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA
| | - Fedor Kouzine
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA
| | - Aswin S N Seshasayee
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, Karnataka, India
| | - Sankar Adhya
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA
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39
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Structural Dynamics and Mechanochemical Coupling in DNA Gyrase. J Mol Biol 2016; 428:1833-45. [PMID: 27016205 DOI: 10.1016/j.jmb.2016.03.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/16/2016] [Accepted: 03/15/2016] [Indexed: 11/22/2022]
Abstract
Gyrase is a molecular motor that harnesses the free energy of ATP hydrolysis to perform mechanical work on DNA. The enzyme specifically introduces negative supercoiling in a process that must coordinate fuel consumption with DNA cleavage and religation and with numerous conformational changes in both the protein and DNA components of a large nucleoprotein complex. Here we present a current understanding of mechanochemical coupling in this essential molecular machine, with a focus on recent diverse biophysical approaches that have revealed details of molecular architectures, new conformational intermediates, structural transitions modulated by ATP binding, and the influence of mechanics on motor function. Recent single-molecule assays have also illuminated the reciprocal relationships between supercoiling and transcription, an illustration of mechanical interactions between gyrase and other molecular machines at the heart of chromosomal biology.
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40
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Mobley HLT. Measuring Escherichia coli Gene Expression during Human Urinary Tract Infections. Pathogens 2016; 5:pathogens5010007. [PMID: 26784237 PMCID: PMC4810128 DOI: 10.3390/pathogens5010007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 11/25/2022] Open
Abstract
Extraintestinal Escherichiacoli (E. coli) evolved by acquisition of pathogenicity islands, phage, plasmids, and DNA segments by horizontal gene transfer. Strains are heterogeneous but virulent uropathogenic isolates more often have specific fimbriae, toxins, and iron receptors than commensal strains. One may ask whether it is the virulence factors alone that are required to establish infection. While these virulence factors clearly contribute strongly to pathogenesis, bacteria must survive by metabolizing nutrients available to them. By constructing mutants in all major metabolic pathways and co-challenging mice transurethrally with each mutant and the wild type strain, we identified which major metabolic pathways are required to infect the urinary tract. We must also ask what else is E. coli doing in vivo? To answer this question, we examined the transcriptome of E. coli CFT073 in the murine model of urinary tract infection (UTI) as well as for E. coli strains collected and analyzed directly from the urine of patients attending either a urology clinic or a university health clinic for symptoms of UTI. Using microarrays and RNA-seq, we measured in vivo gene expression for these uropathogenic E. coli strains, identifying genes upregulated during murine and human UTI. Our findings allow us to propose a new definition of bacterial virulence.
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Affiliation(s)
- Harry L T Mobley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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41
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Escobar-Bravo R, Alba JM, Pons C, Granell A, Kant MR, Moriones E, Fernández-Muñoz R. A Jasmonate-Inducible Defense Trait Transferred from Wild into Cultivated Tomato Establishes Increased Whitefly Resistance and Reduced Viral Disease Incidence. FRONTIERS IN PLANT SCIENCE 2016; 7:1732. [PMID: 27920785 PMCID: PMC5118631 DOI: 10.3389/fpls.2016.01732] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 11/03/2016] [Indexed: 05/21/2023]
Abstract
Whiteflies damage tomatoes mostly via the viruses they transmit. Cultivated tomatoes lack many of the resistances of their wild relatives. In order to increase protection to its major pest, the whitefly Bemisia tabaci and its transmitted Tomato Yellow Leaf Curl Virus (TYLCV), we introgressed a trichome-based resistance trait from the wild tomato Solanum pimpinellifolium into cultivated tomato, Solanum lycopersicum. The tomato backcross line BC5S2 contains acylsucrose-producing type-IV trichomes, unlike cultivated tomatoes, and exhibits increased, yet limited protection to whiteflies at early development stages. Treatment of young plants with methyl jasmonate (MeJA) resulted in a 60% increase in type-IV trichome density, acylsucrose production, and enhanced resistance to whiteflies, leading to 50% decrease in the virus disease incidence compared to cultivated tomato. Using transcriptomics, metabolite analysis, and insect bioassays we established the basis of this inducible resistance. We found that MeJA activated the expression of the genes involved in the biosynthesis of the defensive acylsugars in young BC5S2 plants leading to enhanced chemical defenses in their acquired type-IV trichomes. Our results show that not only constitutive but also these inducible defenses can be transferred from wild into cultivated crops to aid sustainable protection, suggesting that conventional breeding strategies provide a feasible alternative to increase pest resistance in tomato.
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Affiliation(s)
- Rocío Escobar-Bravo
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, Universidad de Málaga – Consejo Superior de Investigaciones CientíficasAlgarrobo-Costa, Spain
| | - Juan M. Alba
- Department of Population Biology, Institute for Biodiversity and Ecosystem Dynamics, University of AmsterdamAmsterdam, Netherlands
| | - Clara Pons
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de ValenciaValencia, Spain
| | - Antonio Granell
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de ValenciaValencia, Spain
| | - Merijn R. Kant
- Department of Population Biology, Institute for Biodiversity and Ecosystem Dynamics, University of AmsterdamAmsterdam, Netherlands
| | - Enrique Moriones
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, Universidad de Málaga – Consejo Superior de Investigaciones CientíficasAlgarrobo-Costa, Spain
| | - Rafael Fernández-Muñoz
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, Universidad de Málaga – Consejo Superior de Investigaciones CientíficasAlgarrobo-Costa, Spain
- *Correspondence: Rafael Fernández-Muñoz,
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42
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Abstract
Escherichia coli and Salmonella encounter osmotic pressure variations in natural environments that include host tissues, food, soil, and water. Osmotic stress causes water to flow into or out of cells, changing their structure, physics, and chemistry in ways that perturb cell functions. E. coli and Salmonella limit osmotically induced water fluxes by accumulating and releasing electrolytes and small organic solutes, some denoted compatible solutes because they accumulate to high levels without disturbing cell functions. Osmotic upshifts inhibit membrane-based energy transduction and macromolecule synthesis while activating existing osmoregulatory systems and specifically inducing osmoregulatory genes. The osmoregulatory response depends on the availability of osmoprotectants (exogenous organic compounds that can be taken up to become compatible solutes). Without osmoprotectants, K+ accumulates with counterion glutamate, and compatible solute trehalose is synthesized. Available osmoprotectants are taken up via transporters ProP, ProU, BetT, and BetU. The resulting compatible solute accumulation attenuates the K+ glutamate response and more effectively restores cell hydration and growth. Osmotic downshifts abruptly increase turgor pressure and strain the cytoplasmic membrane. Mechanosensitive channels like MscS and MscL open to allow nonspecific solute efflux and forestall cell lysis. Research frontiers include (i) the osmoadaptive remodeling of cell structure, (ii) the mechanisms by which osmotic stress alters gene expression, (iii) the mechanisms by which transporters and channels detect and respond to osmotic pressure changes, (iv) the coordination of osmoregulatory programs and selection of available osmoprotectants, and (v) the roles played by osmoregulatory mechanisms as E. coli and Salmonella survive or thrive in their natural environments.
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43
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Metabolic shift of Escherichia coli under salt stress in the presence of glycine betaine. Appl Environ Microbiol 2015; 80:4745-56. [PMID: 24858086 DOI: 10.1128/aem.00599-14] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An important area of food safety focuses on bacterial survival and growth in unfavorable environments. In order to understand how bacteria adapt to stresses other than nutrient limitation in batch cultures, we need to develop mechanistic models of intracellular regulation and metabolism under stress. We studied the growth of Escherichia coli in minimal medium with added salt and different osmoprotectants. To characterize the metabolic efficiency with a robust parameter, we identified the optical density (OD) values at the inflection points of measured "OD versus time" growth curves and described them as a function of glucose concentration. We found that the metabolic efficiency parameter did not necessarily follow the trend of decreasing specific growth rate as the salt concentration increased. In the absence of osmoprotectant, or in the presence of proline, the metabolic efficiency decreased with increasing NaCl concentration. However, in the presence of choline or glycine betaine, it increased between 2 and 4.5% NaCl before declining at 5% NaCl and above. Microarray analysis of the transcriptional network and proteomics analysis with glycine betaine in the medium indicated that between 4.5 and 5% NaCl, the metabolism switched from aerobic to fermentative pathways and that the response to osmotic stress is similar to that for oxidative stress. We conclude that, although the growth rate appeared to decrease smoothly with increasing NaCl, the metabolic strategy of cells changed abruptly at a threshold concentration of NaCl.
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44
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Piras C, Soggiu A, Greco V, Martino PA, Del Chierico F, Putignani L, Urbani A, Nally JE, Bonizzi L, Roncada P. Mechanisms of antibiotic resistance to enrofloxacin in uropathogenic Escherichia coli in dog. J Proteomics 2015; 127:365-76. [PMID: 26066767 DOI: 10.1016/j.jprot.2015.05.040] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 05/12/2015] [Accepted: 05/29/2015] [Indexed: 01/25/2023]
Abstract
Escherichia coli (E. coli) urinary tract infections (UTIs) are becoming a serious problem both for pets and humans (zoonosis) due to the close contact and to the increasing resistance to antibiotics. This study has been performed in order to unravel the mechanism of induced enrofloxacin resistance in canine E. coli isolates that represent a good tool to study this pathology. The isolated E. coli has been induced with enrofloxacin and studied through 2D DIGE and shotgun MS. Discovered differentially expressed proteins are principally involved in antibiotic resistance and linked to oxidative stress response, to DNA protection and to membrane permeability. Moreover, since enrofloxacin is an inhibitor of DNA gyrase, the overexpression of DNA starvation/stationary phase protection protein (Dsp) could be a central point to discover the mechanism of this clone to counteract the effects of enrofloxacin. In parallel, the dramatic decrease of the synthesis of the outer membrane protein W, which represents one of the main gates for enrofloxacin entrance, could explain additional mechanism of E. coli defense against this antibiotic. All 2D DIGE and MS data have been deposited into the ProteomeXchange Consortium with identifier PXD002000 and DOI http://dx.doi.org/10.6019/PXD002000. This article is part of a Special Issue entitled: HUPO 2014.
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Affiliation(s)
- Cristian Piras
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli studi di Milano, Milan, Italy
| | - Alessio Soggiu
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli studi di Milano, Milan, Italy
| | - Viviana Greco
- Fondazione Santa Lucia - IRCCS, Rome, Italy; Dipartimento di Medicina Sperimentale e Chirurgia, Università degli Studi di Roma "Tor Vergata", Italy
| | - Piera Anna Martino
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli studi di Milano, Milan, Italy
| | | | - Lorenza Putignani
- Parasitology and Metagenomics Units, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Andrea Urbani
- Fondazione Santa Lucia - IRCCS, Rome, Italy; Dipartimento di Medicina Sperimentale e Chirurgia, Università degli Studi di Roma "Tor Vergata", Italy
| | - Jarlath E Nally
- Bacterial Diseases of Livestock Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA 50010, United States
| | - Luigi Bonizzi
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli studi di Milano, Milan, Italy
| | - Paola Roncada
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli studi di Milano, Milan, Italy; Istituto Sperimentale Italiano L. Spallanzani, Milano, Italy.
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45
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Liu L, Si L, Meng X, Luo L. Comparative transcriptomic analysis reveals novel genes and regulatory mechanisms of Tetragenococcus halophilus in response to salt stress. J Ind Microbiol Biotechnol 2015; 42:601-16. [PMID: 25563971 DOI: 10.1007/s10295-014-1579-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 12/25/2014] [Indexed: 11/29/2022]
Abstract
Tetragenococcus halophilus, a moderately halophilic Gram-positive bacterium, was isolated from Chinese style soy sauce. This species is a valuable resource for investigating salt tolerance mechanisms and improving salinity resistance in microorganisms. RNA-seq was used to sequence T. halophilus samples treated with 0 M (T1), 1 M (T2), and 3.5 M NaCl (T3). Comparative transcriptomic analyses of the different treatments were performed using gene ontology and Kyoto encyclopedia of genes and genome. The comparison of T1 and T2 by RNA-seq revealed that genes involved in transcription, translation, membrane system, and division were highly up-regulated under optimum salt condition. The comparison of T2 and T3 showed that genes related to heat shock proteins or the ATP-binding cassette transport systems were significantly up-regulated under maximum-salt condition. In addition, a considerable proportion of the significantly differently expressed genes identified in this study are novel. These data provide a crucial resource that may determine specific responses to salt stress in T. halophilus.
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Affiliation(s)
- Licui Liu
- School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, 510006, China
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46
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Sohm B, Immel F, Bauda P, Pagnout C. Insight into the primary mode of action of TiO2 nanoparticles on Escherichia coli in the dark. Proteomics 2014; 15:98-113. [PMID: 25346333 DOI: 10.1002/pmic.201400101] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 09/22/2014] [Accepted: 10/20/2014] [Indexed: 11/09/2022]
Abstract
Large-scale production and incorporation of titanium dioxide nanoparticles (NP-TiO2 ) in consumer products leads to their potential release into the environment and raises the question of their toxicity. The bactericidal mechanism of NP-TiO2 under UV light is known to involve oxidative stress due to the generation of reactive oxygen species. In the dark, several studies revealed that NP-TiO2 can exert toxicological effects. However, the mode of action of these nanoparticles is still controversial. In the present study, we used a combination of fluorescent probes to show that NP-TiO2 causes Escherichia coli membrane depolarization and loss of integrity, leading to higher cell permeability. Using both transcriptomic and proteomic global approaches we showed that this phenomenon translates into a cellular response to osmotic stress, metabolism of cell envelope components and uptake/metabolism of endogenous and exogenous compounds. This primary mechanism of bacterial NP-TiO2 toxicity is supported by the observed massive cell leakage of K(+) /Mg(2+) concomitant with the entrance of extracellular Na(+), and by the depletion of intracellular ATP level.
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Affiliation(s)
- Bénédicte Sohm
- Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), UMR 7360, Université de Lorraine, Metz, France; CNRS, LIEC, UMR 7360, Metz, France
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47
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Zhang Y, Nandakumar R, Bartelt-Hunt SL, Snow DD, Hodges L, Li X. Quantitative proteomic analysis of the Salmonella-lettuce interaction. Microb Biotechnol 2014; 7:630-7. [PMID: 24512637 PMCID: PMC4265081 DOI: 10.1111/1751-7915.12114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 12/18/2013] [Accepted: 12/18/2013] [Indexed: 11/29/2022] Open
Abstract
Human pathogens can internalize food crops through root and surface uptake and persist inside crop plants. The goal of the study was to elucidate the global modulation of bacteria and plant protein expression after Salmonella internalizes lettuce. A quantitative proteomic approach was used to analyse the protein expression of Salmonella enterica serovar Infantis and lettuce cultivar Green Salad Bowl 24 h after infiltrating S. Infantis into lettuce leaves. Among the 50 differentially expressed proteins identified by comparing internalized S. Infantis against S. Infantis grown in Luria Broth, proteins involved in glycolysis were down-regulated, while one protein involved in ascorbate uptake was up-regulated. Stress response proteins, especially antioxidant proteins, were up-regulated. The modulation in protein expression suggested that internalized S. Infantis might utilize ascorbate as a carbon source and require multiple stress response proteins to cope with stresses encountered in plants. On the other hand, among the 20 differentially expressed lettuce proteins, proteins involved in defense response to bacteria were up-regulated. Moreover, the secreted effector PipB2 of S. Infantis and R proteins of lettuce were induced after bacterial internalization into lettuce leaves, indicating human pathogen S. Infantis triggered the defense mechanisms of lettuce, which normally responds to plant pathogens.
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Affiliation(s)
- Yuping Zhang
- Department of Civil Engineering, University of Nebraska-LincolnLincoln, NE, 68588, USA
| | - Renu Nandakumar
- Proteomics and Metabolomics Core Facility, Redox Biology Center, Department of Biochemistry, University of Nebraska-LincolnLincoln, NE, 68588, USA
| | | | - Daniel D Snow
- School of Natural Resources, University of Nebraska-LincolnLincoln, NE, 68588, USA
| | - Laurie Hodges
- Deptartment of Agronomy & Horticulture, University of Nebraska-LincolnLincoln, NE, 68588, USA
| | - Xu Li
- Department of Civil Engineering, University of Nebraska-LincolnLincoln, NE, 68588, USA
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48
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Murdock L, Burke T, Coumoundouros C, Culham DE, Deutch CE, Ellinger J, Kerr CH, Plater SM, To E, Wright G, Wood JM. Analysis of strains lacking known osmolyte accumulation mechanisms reveals contributions of osmolytes and transporters to protection against abiotic stress. Appl Environ Microbiol 2014; 80:5366-78. [PMID: 24951793 PMCID: PMC4136119 DOI: 10.1128/aem.01138-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 06/17/2014] [Indexed: 11/20/2022] Open
Abstract
Osmolyte accumulation and release can protect cells from abiotic stresses. In Escherichia coli, known mechanisms mediate osmotic stress-induced accumulation of K(+) glutamate, trehalose, or zwitterions like glycine betaine. Previous observations suggested that additional osmolyte accumulation mechanisms (OAMs) exist and their impacts may be abiotic stress specific. Derivatives of the uropathogenic strain CFT073 and the laboratory strain MG1655 lacking known OAMs were created. CFT073 grew without osmoprotectants in minimal medium with up to 0.9 M NaCl. CFT073 and its OAM-deficient derivative grew equally well in high- and low-osmolality urine pools. Urine-grown bacteria did not accumulate large amounts of known or novel osmolytes. Thus, CFT073 showed unusual osmotolerance and did not require osmolyte accumulation to grow in urine. Yeast extract and brain heart infusion stimulated growth of the OAM-deficient MG1655 derivative at high salinity. Neither known nor putative osmoprotectants did so. Glutamate and glutamine accumulated after growth with either organic mixture, and no novel osmolytes were detected. MG1655 derivatives retaining individual OAMs were created. Their abilities to mediate osmoprotection were compared at 15°C, 37°C without or with urea, and 42°C. Stress protection was not OAM specific, and variations in osmoprotectant effectiveness were similar under all conditions. Glycine betaine and dimethylsulfoniopropionate (DMSP) were the most effective. Trimethylamine-N-oxide (TMAO) was a weak osmoprotectant and a particularly effective urea protectant. The effectiveness of glycine betaine, TMAO, and proline as osmoprotectants correlated with their preferential exclusion from protein surfaces, not with their propensity to prevent protein denaturation. Thus, their effectiveness as stress protectants correlated with their ability to rehydrate the cytoplasm.
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Affiliation(s)
- Lindsay Murdock
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Tangi Burke
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Chelsea Coumoundouros
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Doreen E Culham
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Charles E Deutch
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada School of Mathematical and Natural Sciences, Arizona State University at the West Campus, Phoenix, Arizona, USA
| | - James Ellinger
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Craig H Kerr
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Samantha M Plater
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Eric To
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Geordie Wright
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Janet M Wood
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
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49
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Rajendram M, Hurley KA, Foss MH, Thornton KM, Moore JT, Shaw JT, Weibel DB. Gyramides prevent bacterial growth by inhibiting DNA gyrase and altering chromosome topology. ACS Chem Biol 2014; 9:1312-9. [PMID: 24712739 PMCID: PMC4068256 DOI: 10.1021/cb500154m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Antibiotics targeting DNA gyrase
have been a clinical success story
for the past half-century, and the emergence of bacterial resistance
has fueled the search for new gyrase inhibitors. In this paper we
demonstrate that a new class of gyrase inhibitors, the gyramides,
are bacteriostatic agents that competitively inhibit the ATPase activity
of Escherichia coli gyrase and produce supercoiled
DNA in vivo. E. coli cells treated with gyramide
A have abnormally localized, condensed chromosomes that blocks DNA
replication and interrupts chromosome segregation. The resulting alterations
in DNA topology inhibit cell division through a mechanism that involves
the SOS pathway. Importantly, gyramide A is a specific inhibitor of
gyrase and does not inhibit the closely related E. coli enzyme topoisomerase IV. E. coli mutants with reduced
susceptibility to gyramide A do not display cross-resistance to ciprofloxacin
and novobiocin. The results demonstrate that the gyramides prevent
bacterial growth by a mechanism in which the topological state of
chromosomes is altered and halts DNA replication and segregation.
The specificity and activity of the gyramides for inhibiting gyrase
makes these compounds important chemical tools for studying the mechanism
of gyrase and the connection between DNA topology and bacterial cell
division.
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Affiliation(s)
| | | | | | | | - Jared T. Moore
- Department
of Chemistry, University of California-Davis, Davis, California 95616, United States
| | - Jared T. Shaw
- Department
of Chemistry, University of California-Davis, Davis, California 95616, United States
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50
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Pons C, Martí C, Forment J, Crisosto CH, Dandekar AM, Granell A. A bulk segregant gene expression analysis of a peach population reveals components of the underlying mechanism of the fruit cold response. PLoS One 2014; 9:e90706. [PMID: 24598973 PMCID: PMC3944608 DOI: 10.1371/journal.pone.0090706] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 02/04/2014] [Indexed: 11/29/2022] Open
Abstract
Peach fruits subjected for long periods of cold storage are primed to develop chilling injury once fruits are shelf ripened at room temperature. Very little is known about the molecular changes occurring in fruits during cold exposure. To get some insight into this process a transcript profiling analyses was performed on fruits from a PopDG population segregating for chilling injury CI responses. A bulked segregant gene expression analysis based on groups of fruits showing extreme CI responses indicated that the transcriptome of peach fruits was modified already during cold storage consistently with eventual CI development. Most peach cold-responsive genes have orthologs in Arabidopsis that participate in cold acclimation and other stresses responses, while some of them showed expression patterns that differs in fruits according to their susceptibility to develop mealiness. Members of ICE1, CBF1/3 and HOS9 regulons seem to have a prominent role in differential cold responses between low and high sensitive fruits. In high sensitive fruits, an alternative cold response program is detected. This program is probably associated with dehydration/osmotic stress and regulated by ABA, auxins and ethylene. In addition, the observation that tolerant siblings showed a series of genes encoding for stress protective activities with higher expression both at harvest and during cold treatment, suggests that preprogrammed mechanisms could shape fruit ability to tolerate postharvest cold-induced stress. A number of genes differentially expressed were validated and extended to individual genotypes by medium-throughput RT-qPCR. Analyses presented here provide a global view of the responses of peach fruits to cold storage and highlights new peach genes that probably play important roles in the tolerance/sensitivity to cold storage. Our results provide a roadmap for further experiments and would help to develop new postharvest protocols and gene directed breeding strategies to better cope with chilling injury.
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Affiliation(s)
- Clara Pons
- Plant Genomics and Biotechnology lab, Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, Valencia, Spain
| | - Cristina Martí
- Plant Genomics and Biotechnology lab, Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, Valencia, Spain
| | - Javier Forment
- Plant Genomics and Biotechnology lab, Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, Valencia, Spain
| | - Carlos H. Crisosto
- Department of Plant Sciences, University of California Davis, Davis, California, United States of America
| | - Abhaya M. Dandekar
- Department of Plant Sciences, University of California Davis, Davis, California, United States of America
| | - Antonio Granell
- Plant Genomics and Biotechnology lab, Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, Valencia, Spain
- * E-mail:
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