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Arias-Cartin R, Kazemzadeh Ferizhendi K, Séchet E, Pelosi L, Loeuillet C, Pierrel F, Barras F, Bouveret E. Role of the Escherichia coli ubiquinone-synthesizing UbiUVT pathway in adaptation to changing respiratory conditions. mBio 2023; 14:e0329822. [PMID: 37283518 PMCID: PMC10470549 DOI: 10.1128/mbio.03298-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 04/12/2023] [Indexed: 06/08/2023] Open
Abstract
Isoprenoid quinones are essential for cellular physiology. They act as electron and proton shuttles in respiratory chains and various biological processes. Escherichia coli and many α-, β-, and γ-proteobacteria possess two types of isoprenoid quinones: ubiquinone (UQ) is mainly used under aerobiosis, while demethylmenaquinones (DMK) are mostly used under anaerobiosis. Yet, we recently established the existence of an anaerobic O2-independent UQ biosynthesis pathway controlled by ubiT, ubiU, and ubiV genes. Here, we characterize the regulation of ubiTUV genes in E. coli. We show that the three genes are transcribed as two divergent operons that are both under the control of the O2-sensing Fnr transcriptional regulator. Phenotypic analyses using a menA mutant devoid of DMK revealed that UbiUV-dependent UQ synthesis is essential for nitrate respiration and uracil biosynthesis under anaerobiosis, while it contributes, though modestly, to bacterial multiplication in the mouse gut. Moreover, we showed by genetic study and 18O2 labeling that UbiUV contributes to the hydroxylation of ubiquinone precursors through a unique O2-independent process. Last, we report the crucial role of ubiT in allowing E. coli to shift efficiently from anaerobic to aerobic conditions. Overall, this study uncovers a new facet of the strategy used by E. coli to adjust its metabolism on changing O2 levels and respiratory conditions. This work links respiratory mechanisms to phenotypic adaptation, a major driver in the capacity of E. coli to multiply in gut microbiota and of facultative anaerobic pathogens to multiply in their host. IMPORTANCE Enterobacteria multiplication in the gastrointestinal tract is linked to microaerobic respiration and associated with various inflammatory bowel diseases. Our study focuses on the biosynthesis of ubiquinone, a key player in respiratory chains, under anaerobiosis. The importance of this study stems from the fact that UQ usage was for long considered to be restricted to aerobic conditions. Here we investigated the molecular mechanism allowing UQ synthesis in the absence of O2 and searched for the anaerobic processes that UQ is fueling in such conditions. We found that UQ biosynthesis involves anaerobic hydroxylases, that is, enzymes able to insert an O atom in the absence of O2. We also found that anaerobically synthesized UQ can be used for respiration on nitrate and the synthesis of pyrimidine. Our findings are likely to be applicable to most facultative anaerobes, which count many pathogens (Salmonella, Shigella, and Vibrio) and will help in unraveling microbiota dynamics.
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Affiliation(s)
- Rodrigo Arias-Cartin
- Département de Microbiologie, Institut Pasteur, Université Paris-Cité, UMR CNRS 6047, SAMe Unit, Paris, France
| | | | - Emmanuel Séchet
- Département de Microbiologie, Institut Pasteur, Université Paris-Cité, UMR CNRS 6047, SAMe Unit, Paris, France
| | - Ludovic Pelosi
- Univ. Grenoble Alpes, CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Grenoble, France
| | - Corinne Loeuillet
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, France
| | - Fabien Pierrel
- Univ. Grenoble Alpes, CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Grenoble, France
| | - Frédéric Barras
- Département de Microbiologie, Institut Pasteur, Université Paris-Cité, UMR CNRS 6047, SAMe Unit, Paris, France
| | - Emmanuelle Bouveret
- Département de Microbiologie, Institut Pasteur, Université Paris-Cité, UMR CNRS 6047, SAMe Unit, Paris, France
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Sun D, Zhou X, Liu C, Zhu J, Ru Y, Liu W, Liu J. Fnr Negatively Regulates Prodigiosin Synthesis in Serratia sp. ATCC 39006 During Aerobic Fermentation. Front Microbiol 2021; 12:734854. [PMID: 34603264 PMCID: PMC8485047 DOI: 10.3389/fmicb.2021.734854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/20/2021] [Indexed: 12/18/2022] Open
Abstract
The well-known Crp/Fnr family regulator Fnr has long been recognized as an oxygen sensor to regulate multiple biological processes, including the switch between aerobic/anaerobic metabolism, nitrogen fixation, bioluminescence, infection, and virulence. In most cases, Fnr was found to be active under anaerobic conditions. However, its role in aerobic antibiotic metabolism has not yet been revealed. In this research, we report that in the model organism, Serratia sp. ATCC 39006, Fnr (Ser39006_013370) negatively regulates prodigiosin production by binding to the spacer between the −10 and −35 region in the promoter of prodigiosin biosynthetic gene cluster under aerobic conditions. Fnr was also shown to modulate the anti-bacterial activity and motility by regulating pathway-specific regulatory genes, indicating that Fnr acts as a global regulator in Serratia sp. ATCC 39006. For the first time, we describe that Fnr regulates antibiotic synthesis in the presence of oxygen, which expands the known physiological functions of Fnr and benefits the further investigation of this important transcriptional regulator.
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Affiliation(s)
- Di Sun
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Xuge Zhou
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Cong Liu
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Jingrong Zhu
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Yunrui Ru
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Weijie Liu
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Jiawen Liu
- Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
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Shi H, Li Y, Hao T, Liu X, Zhao X, Chen S. The Role of Fnr Paralogs in Controlling Anaerobic Metabolism in the Diazotroph Paenibacillus polymyxa WLY78. Appl Environ Microbiol 2020; 86:e03012-19. [PMID: 32198173 DOI: 10.1128/AEM.03012-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 02/28/2020] [Indexed: 11/20/2022] Open
Abstract
Fnr is a transcriptional regulator that controls the expression of a variety of genes in response to oxygen limitation in bacteria. Genome sequencing revealed four genes (fnr1, fnr3, fnr5, and fnr7) coding for Fnr proteins in Paenibacillus polymyxa WLY78. Fnr1 and Fnr3 showed more similarity to each other than to Fnr5 and Fnr7. Also, Fnr1 and Fnr3 exhibited high similarity with Bacillus cereus Fnr and Bacillus subtilis Fnr in sequence and structures. Both the aerobically purified His-tagged Fnr1 and His-tagged Fnr3 in Escherichia coli could bind to the specific DNA promoter. Deletion analysis showed that the four fnr genes, especially fnr1 and fnr3, have significant impacts on growth and nitrogenase activity. Single deletion of fnr1 or fnr3 led to a 50% reduction in nitrogenase activity, and double deletion of fnr1 and fnr3 resulted to a 90% reduction in activity. Genome-wide transcription analysis showed that Fnr1 and Fnr3 indirectly activated expression of nif (nitrogen fixation) genes and Fe transport genes under anaerobic conditions. Fnr1 and Fnr3 inhibited expression of the genes involved in the aerobic respiratory chain and activated expression of genes responsible for anaerobic electron acceptor genes.IMPORTANCE The members of the nitrogen-fixing Paenibacillus spp. have great potential to be used as a bacterial fertilizer in agriculture. However, the functions of the fnr gene(s) in nitrogen fixation and other metabolisms in Paenibacillus spp. are not known. Here, we found that in P. polymyxa WLY78, Fnr1 and Fnr3 were responsible for regulation of numerous genes in response to changes in oxygen levels, but Fnr5 and Fnr7 exhibited little effect. Fnr1 and Fnr3 indirectly or directly regulated many types of important metabolism, such as nitrogen fixation, Fe uptake, respiration, and electron transport. This study not only reveals the function of the fnr genes of P. polymyxa WLY78 in nitrogen fixation and other metabolisms but also will provide insight into the evolution and regulatory mechanisms of fnr in Paenibacillus.
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Fernández PA, Velásquez F, Garcias-Papayani H, Amaya FA, Ortega J, Gómez S, Santiviago CA, Álvarez SA. Fnr and ArcA Regulate Lipid A Hydroxylation in Salmonella Enteritidis by Controlling lpxO Expression in Response to Oxygen Availability. Front Microbiol 2018; 9:1220. [PMID: 29937757 PMCID: PMC6002686 DOI: 10.3389/fmicb.2018.01220] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/18/2018] [Indexed: 12/22/2022] Open
Abstract
Lipid A is the bioactive component of lipopolysaccharide, and presents a dynamic structure that undergoes modifications in response to environmental signals. Many of these structural modifications influence Salmonella virulence. This is the case of lipid A hydroxylation, a modification catalyzed by the dioxygenase LpxO. Although it has been established that oxygen is required for lipid A hydroxylation acting as substrate of LpxO in Salmonella, an additional regulatory role for oxygen in lpxO expression has not been described. The existence of this regulation could be relevant considering that Salmonella faces low oxygen tension during infection. This condition leads to an adaptive response by changing the expression of numerous genes, and transcription factors Fnr and ArcA are major regulators of this process. In this work, we describe for the first time that lipid A hydroxylation and lpxO expression are modulated by oxygen availability in Salmonella enterica serovar Enteritidis (S. Enteritidis). Biochemical and genetic analyses indicate that this process is regulated by Fnr and ArcA controlling the expression of lpxO. In addition, according to our results, this regulation occurs by direct binding of both transcription factors to specific elements present in the lpxO promoter region. Altogether, our observations revealed a novel role for oxygen acting as an environment signal controlling lipid A hydroxylation in S. Enteritidis.
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Affiliation(s)
- Paulina A Fernández
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Felipe Velásquez
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Héctor Garcias-Papayani
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Fernando A Amaya
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Jaime Ortega
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Sebastián Gómez
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Carlos A Santiviago
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Sergio A Álvarez
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
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Batista MB, Teixeira CS, Sfeir MZT, Alves LPS, Valdameri G, Pedrosa FDO, Sassaki GL, Steffens MBR, de Souza EM, Dixon R, Müller-Santos M. PHB Biosynthesis Counteracts Redox Stress in Herbaspirillum seropedicae. Front Microbiol 2018; 9:472. [PMID: 29599762 PMCID: PMC5862806 DOI: 10.3389/fmicb.2018.00472] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 02/28/2018] [Indexed: 11/25/2022] Open
Abstract
The ability of bacteria to produce polyhydroxyalkanoates such as poly(3-hydroxybutyrate) (PHB) enables provision of a carbon storage molecule that can be mobilized under demanding physiological conditions. However, the precise function of PHB in cellular metabolism has not been clearly defined. In order to determine the impact of PHB production on global physiology, we have characterized the properties of a ΔphaC1 mutant strain of the diazotrophic bacterium Herbaspirillum seropedicae. The absence of PHB in the mutant strain not only perturbs redox balance and increases oxidative stress, but also influences the activity of the redox-sensing Fnr transcription regulators, resulting in significant changes in expression of the cytochrome c-branch of the electron transport chain. The synthesis of PHB is itself dependent on the Fnr1 and Fnr3 proteins resulting in a cyclic dependency that couples synthesis of PHB with redox regulation. Transcriptional profiling of the ΔphaC1 mutant reveals that the loss of PHB synthesis affects the expression of many genes, including approximately 30% of the Fnr regulon.
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Affiliation(s)
- Marcelo B Batista
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil.,Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Cícero S Teixeira
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Michelle Z T Sfeir
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Luis P S Alves
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Glaucio Valdameri
- Department of Clinical Analysis, Universidade Federal do Paraná, Curitiba, Brazil
| | | | - Guilherme L Sassaki
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Maria B R Steffens
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Emanuel M de Souza
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Ray Dixon
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Marcelo Müller-Santos
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
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Cai D, Hu S, Chen Y, Liu L, Yang S, Ma X, Chen S. Enhanced Production of Poly-γ-glutamic acid by Overexpression of the Global Anaerobic Regulator Fnr in Bacillus licheniformis WX-02. Appl Biochem Biotechnol 2018; 185:958-970. [PMID: 29388009 DOI: 10.1007/s12010-018-2693-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
Abstract
Poly-γ-glutamic acid is a multi-functional biopolymer with various applications. ATP supply plays an important role in poly-γ-glutamic acid (γ-PGA) synthesis. Global anaerobic regulator Fnr plays a key role in anaerobic adaptation and nitrate respiration, which might affect ATP generation during γ-PGA synthesis. In this study, we have improved γ-PGA production by overexpression of Fnr in Bacillus licheniformis WX-02. First, the gene fnr was knocked out in WX-02, and the γ-PGA yields have no significant differences between WX-02 and the fnr-deficient strain WXΔfnr in the medium without nitrate (BFC medium). However, the γ-PGA yield of 8.95 g/L, which was produced by WXΔfnr in the medium with nitrate addition (BFCN medium), decreased by 74% compared to WX-02 (34.53 g/L). Then, the fnr complementation strain WXΔfnr/pHY-fnr restored the γ-PGA synthesis capability, and γ-PGA yield was increased by 13% in the Fnr overexpression strain WX/pHY-fnr (39.96 g/L) in BFCN medium, compared to WX/pHY300 (35.41 g/L). Furthermore, the transcriptional levels of narK, narG, and hmp were increased by 5.41-, 4.93-, and 3.93-fold in WX/pHY-fnr, respectively, which led to the increases of nitrate consumption rate and ATP supply for γ-PGA synthesis. Collectively, Fnr affects γ-PGA synthesis mainly through manipulating the expression level of nitrate metabolism, and this study provides a novel strategy to improve γ-PGA production by overexpression of Fnr.
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Affiliation(s)
- Dongbo Cai
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Shiying Hu
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Yaozhong Chen
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Li Liu
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Shihui Yang
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Xin Ma
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China.
| | - Shouwen Chen
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China.
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Matsuoka Y, Kurata H. Modeling and simulation of the redox regulation of the metabolism in Escherichia coli at different oxygen concentrations. Biotechnol Biofuels 2017; 10:183. [PMID: 28725263 PMCID: PMC5512849 DOI: 10.1186/s13068-017-0867-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 07/05/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Microbial production of biofuels and biochemicals from renewable feedstocks has received considerable recent attention from environmental protection and energy production perspectives. Many biofuels and biochemicals are produced by fermentation under oxygen-limited conditions following initiation of aerobic cultivation to enhance the cell growth rate. Thus, it is of significant interest to investigate the effect of dissolved oxygen concentration on redox regulation in Escherichia coli, a particularly popular cellular factory due to its high growth rate and well-characterized physiology. For this, the systems biology approach such as modeling is powerful for the analysis of the metabolism and for the design of microbial cellular factories. RESULTS Here, we developed a kinetic model that describes the dynamics of fermentation by taking into account transcription factors such as ArcA/B and Fnr, respiratory chain reactions and fermentative pathways, and catabolite regulation. The hallmark of the kinetic model is its ability to predict the dynamics of metabolism at different dissolved oxygen levels and facilitate the rational design of cultivation methods. The kinetic model was verified based on the experimental data for a wild-type E. coli strain. The model reasonably predicted the metabolic characteristics and molecular mechanisms of fnr and arcA gene-knockout mutants. Moreover, an aerobic-microaerobic dual-phase cultivation method for lactate production in a pfl-knockout mutant exhibited promising yield and productivity. CONCLUSIONS It is quite important to understand metabolic regulation mechanisms from both scientific and engineering points of view. In particular, redox regulation in response to oxygen limitation is critically important in the practical production of biofuel and biochemical compounds. The developed model can thus be used as a platform for designing microbial factories to produce a variety of biofuels and biochemicals.
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Affiliation(s)
- Yu Matsuoka
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka, 820-8502 Japan
| | - Hiroyuki Kurata
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka, 820-8502 Japan
- Biomedical Informatics R&D Center, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka, 820-8502 Japan
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Silva-Valenzuela CA, Velásquez F, Peñailillo J, Garcias-Papayani H, Fernández P, Tobar P, Contreras I, Santiviago CA, Álvarez SA. O-antigen chain-length distribution in Salmonella enterica serovar Enteritidis is regulated by oxygen availability. Biochem Biophys Res Commun 2016; 477:563-567. [PMID: 27343553 DOI: 10.1016/j.bbrc.2016.06.074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 06/15/2016] [Indexed: 10/21/2022]
Abstract
Lipopolysaccharide (LPS) consists of three covalently linked domains: the lipid A, the core region and the O antigen (OAg), consisting of repeats of an oligosaccharide. Salmonella enterica serovar Enteritidis (S. Enteritidis) produces a LPS with two OAg preferred chain lengths: a long (L)-OAg controlled by WzzSE and a very long (VL)-OAg controlled by WzzfepE. In this work, we show that OAg produced by S. Enteritidis grown in E minimal medium also presented two preferred chain-lengths. However, a simultaneous and opposing change in the production of L-OAg and VL-OAg was observed in response to oxygen availability. Biochemical and genetics analyses indicate that this process is regulated by transcriptional factors Fnr and ArcA by means of controlling the transcription of genes encoding WzzSE and WzzfepE in response to oxygen availability. Thus, our results revealed a sophisticated regulatory mechanism involved in the adaptation of S. Enteritidis to one of the main environmental cues faced by this pathogen during infection.
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Affiliation(s)
- Cecilia A Silva-Valenzuela
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile; Department of Molecular Biology and Microbiology, Tufts University, Boston, MA, USA
| | - Felipe Velásquez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Johany Peñailillo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Héctor Garcias-Papayani
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Paulina Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Pía Tobar
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Inés Contreras
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Carlos A Santiviago
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Sergio A Álvarez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
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