1
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Brunson DN, Colomer-Winter C, Lam LN, Lemos JA. Identification of Multiple Iron Uptake Mechanisms in Enterococcus faecalis and Their Relationship to Virulence. Infect Immun 2023; 91:e0049622. [PMID: 36912636 PMCID: PMC10112239 DOI: 10.1128/iai.00496-22] [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: 11/03/2022] [Accepted: 02/17/2023] [Indexed: 03/14/2023] Open
Abstract
Among the unfavorable conditions bacteria encounter within the host is restricted access to essential trace metals such as iron. To overcome iron deficiency, bacteria deploy multiple strategies to scavenge iron from host tissues, with abundant examples of iron acquisition systems being implicated in bacterial pathogenesis. Yet the mechanisms utilized by the major nosocomial pathogen Enterococcus faecalis to maintain intracellular iron balance are poorly understood. In this study, we conducted a systematic investigation to identify and characterize the iron acquisition mechanisms of E. faecalis and to determine their contribution to virulence. Bioinformatic analysis and literature surveys revealed that E. faecalis possesses three conserved iron uptake systems. Through transcriptomics, we discovered two novel ABC-type transporters that mediate iron uptake. While inactivation of a single transporter had minimal impact on the ability of E. faecalis to maintain iron homeostasis, inactivation of all five systems (Δ5Fe strain) disrupted intracellular iron homeostasis and considerably impaired cell growth under iron deficiency. Virulence of the Δ5Fe strain was generally impaired in different animal models but showed niche-specific variations in mouse models, leading us to suspect that heme can serve as an iron source to E. faecalis during mammalian infections. Indeed, heme supplementation restored growth of Δ5Fe under iron depletion and virulence in an invertebrate infection model. This study revealed that the collective contribution of five iron transporters promotes E. faecalis virulence and that the ability to acquire and utilize heme as an iron source is critical to the systemic dissemination of E. faecalis.
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Affiliation(s)
- Debra N. Brunson
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Cristina Colomer-Winter
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Ling Ning Lam
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - José A. Lemos
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
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2
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Ali IAA, Cheung GS, Neelakantan P. Transition Metals and
Enterococcus faecalis
: Homeostasis, Virulence and Perspectives. Mol Oral Microbiol 2022; 37:276-291. [DOI: 10.1111/omi.12391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 09/07/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Islam A. A. Ali
- Department of Endodontics Faculty of Dentistry Mansoura University Mansoura Egypt
| | - Gary S.P. Cheung
- Discipline of Endodontology Division of Restorative Dental Sciences Faculty of Dentistry The University of Hong Kong Hong Kong SAR
| | - Prasanna Neelakantan
- Discipline of Endodontology Division of Restorative Dental Sciences Faculty of Dentistry The University of Hong Kong Hong Kong SAR
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3
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Ha KP, Clarke RS, Kim GL, Brittan JL, Rowley JE, Mavridou DAI, Parker D, Clarke TB, Nobbs AH, Edwards AM. Staphylococcal DNA Repair Is Required for Infection. mBio 2020; 11:e02288-20. [PMID: 33203752 PMCID: PMC7683395 DOI: 10.1128/mbio.02288-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 10/14/2020] [Indexed: 01/07/2023] Open
Abstract
To cause infection, Staphylococcus aureus must withstand damage caused by host immune defenses. However, the mechanisms by which staphylococcal DNA is damaged and repaired during infection are poorly understood. Using a panel of transposon mutants, we identified the rexBA operon as being important for the survival of Staphylococcus aureus in whole human blood. Mutants lacking rexB were also attenuated for virulence in murine models of both systemic and skin infections. We then demonstrated that RexAB is a member of the AddAB family of helicase/nuclease complexes responsible for initiating the repair of DNA double-strand breaks. Using a fluorescent reporter system, we were able to show that neutrophils cause staphylococcal DNA double-strand breaks through reactive oxygen species (ROS) generated by the respiratory burst, which are repaired by RexAB, leading to the induction of the mutagenic SOS response. We found that RexAB homologues in Enterococcus faecalis and Streptococcus gordonii also promoted the survival of these pathogens in human blood, suggesting that DNA double-strand break repair is required for Gram-positive bacteria to survive in host tissues. Together, these data demonstrate that DNA is a target of host immune cells, leading to double-strand breaks, and that the repair of this damage by an AddAB-family enzyme enables the survival of Gram-positive pathogens during infection.IMPORTANCE To cause infection, bacteria must survive attack by the host immune system. For many bacteria, including the major human pathogen Staphylococcus aureus, the greatest threat is posed by neutrophils. These immune cells ingest the invading organisms and try to kill them with a cocktail of chemicals that includes reactive oxygen species (ROS). The ability of S. aureus to survive this attack is crucial for the progression of infection. However, it was not clear how the ROS damaged S. aureus and how the bacterium repaired this damage. In this work, we show that ROS cause breaks in the staphylococcal DNA, which must be repaired by a two-protein complex known as RexAB; otherwise, the bacterium is killed, and it cannot sustain infection. This provides information on the type of damage that neutrophils cause S. aureus and the mechanism by which this damage is repaired, enabling infection.
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Affiliation(s)
- Kam Pou Ha
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Rebecca S Clarke
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Gyu-Lee Kim
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Jane L Brittan
- Bristol Dental School, University of Bristol, Bristol, United Kingdom
| | - Jessica E Rowley
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Despoina A I Mavridou
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, USA
| | - Dane Parker
- Department of Pathology, Immunology and Laboratory Medicine, Center for Immunity and Inflammation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Thomas B Clarke
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Angela H Nobbs
- Bristol Dental School, University of Bristol, Bristol, United Kingdom
| | - Andrew M Edwards
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
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4
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Tarrant E, P Riboldi G, McIlvin MR, Stevenson J, Barwinska-Sendra A, Stewart LJ, Saito MA, Waldron KJ. Copper stress in Staphylococcus aureus leads to adaptive changes in central carbon metabolism. Metallomics 2020; 11:183-200. [PMID: 30443649 PMCID: PMC6350627 DOI: 10.1039/c8mt00239h] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Copper toxicity has been a long-term selection pressure on bacteria due to its presence in the environment and its use as an antimicrobial agent by grazing protozoa, by phagocytic cells of the immune system, and in man-made medical and commercial products. There is recent evidence that exposure to increased copper stress may have been a key driver in the evolution and spread of methicillin-resistant Staphylococcus aureus, a globally important pathogen that causes significant mortality and morbidity worldwide. Yet it is unclear how S. aureus physiology is affected by copper stress or how it adapts in order to be able to grow in the presence of excess copper. Here, we have determined quantitatively how S. aureus alters its proteome during growth under copper stress conditions, comparing this adaptive response in two different types of growth regime. We found that the adaptive response involves induction of the conserved copper detoxification system as well as induction of enzymes of central carbon metabolism, with only limited induction of proteins involved in the oxidative stress response. Further, we identified a protein that binds copper inside S. aureus cells when stressed by copper excess. This copper-binding enzyme, a glyceraldehyde-3-phosphate dehydrogenase essential for glycolysis, is inhibited by copper in vitro and inside S. aureus cells. Together, our data demonstrate that copper stress leads to the inhibition of glycolysis in S. aureus, and that the bacterium adapts to this stress by altering its central carbon utilisation pathways.
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Affiliation(s)
- Emma Tarrant
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
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5
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Cortés MP, Acuña V, Travisany D, Siegel A, Maass A, Latorre M. Integration of Biological Networks for Acidithiobacillus thiooxidans Describes a Modular Gene Regulatory Organization of Bioleaching Pathways. Front Mol Biosci 2020; 6:155. [PMID: 31998751 PMCID: PMC6966769 DOI: 10.3389/fmolb.2019.00155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 12/13/2019] [Indexed: 11/13/2022] Open
Abstract
Acidithiobacillus thiooxidans is one of the most studied biomining species, highlighting its ability to oxidize reduced inorganic sulfur compounds, coupled with its elevated capacity to live under an elevated concentration of heavy metals. In this work, using an in silico semi-automatic genome scale approach, two biological networks for A. thiooxidans Licanantay were generated: (i) An affinity transcriptional regulatory network composed of 42 regulatory family genes and 1,501 operons (57% genome coverage) linked through 2,646 putative DNA binding sites (arcs), (ii) A metabolic network reconstruction made of 523 genes and 1,203 reactions (22 pathways related to biomining processes). Through the identification of confident connections between both networks (V-shapes), it was possible to identify a sub-network of transcriptional factor (34 regulators) regulating genes (61 operons) encoding for proteins involved in biomining-related pathways. Network analysis suggested that transcriptional regulation of biomining genes is organized into different modules. The topological parameters showed a high hierarchical organization by levels inside this network (14 layers), highlighting transcription factors CysB, LysR, and IHF as complex modules with high degree and number of controlled pathways. In addition, it was possible to identify transcription factor modules named primary regulators (not controlled by other regulators in the sub-network). Inside this group, CysB was the main module involved in gene regulation of several bioleaching processes. In particular, metabolic processes related to energy metabolism (such as sulfur metabolism) showed a complex integrated regulation, where different primary regulators controlled several genes. In contrast, pathways involved in iron homeostasis and oxidative stress damage are mainly regulated by unique primary regulators, conferring Licanantay an efficient, and specific metal resistance response. This work shows new evidence in terms of transcriptional regulation at a systems level and broadens the study of bioleaching in A. thiooxidans species.
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Affiliation(s)
- María Paz Cortés
- Center for Mathematical Modeling, Universidad de Chile and UMI CNRS 2807, Santiago, Chile.,Center for Genome Regulation, Universidad de Chile, Santiago, Chile
| | - Vicente Acuña
- Center for Mathematical Modeling, Universidad de Chile and UMI CNRS 2807, Santiago, Chile
| | - Dante Travisany
- Center for Mathematical Modeling, Universidad de Chile and UMI CNRS 2807, Santiago, Chile.,Center for Genome Regulation, Universidad de Chile, Santiago, Chile
| | - Anne Siegel
- IRISA, UMR 6074, CNRS, Rennes, France.,INRIA, Dyliss Team, Centre Rennes-Bretagne-Atlantique, Rennes, France
| | - Alejandro Maass
- Center for Mathematical Modeling, Universidad de Chile and UMI CNRS 2807, Santiago, Chile.,Center for Genome Regulation, Universidad de Chile, Santiago, Chile.,Department of Mathematical Engineering, Universidad de Chile, Santiago, Chile
| | - Mauricio Latorre
- Center for Mathematical Modeling, Universidad de Chile and UMI CNRS 2807, Santiago, Chile.,Center for Genome Regulation, Universidad de Chile, Santiago, Chile.,Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile.,Instituto de Ciencias de la Ingeniería, Universidad de O'Higgins, Rancagua, Chile
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6
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Adaptation to Adversity: the Intermingling of Stress Tolerance and Pathogenesis in Enterococci. Microbiol Mol Biol Rev 2019; 83:83/3/e00008-19. [PMID: 31315902 DOI: 10.1128/mmbr.00008-19] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Enterococcus is a diverse and rugged genus colonizing the gastrointestinal tract of humans and numerous hosts across the animal kingdom. Enterococci are also a leading cause of multidrug-resistant hospital-acquired infections. In each of these settings, enterococci must contend with changing biophysical landscapes and innate immune responses in order to successfully colonize and transit between hosts. Therefore, it appears that the intrinsic durability that evolved to make enterococci optimally competitive in the host gastrointestinal tract also ideally positioned them to persist in hospitals, despite disinfection protocols, and acquire new antibiotic resistances from other microbes. Here, we discuss the molecular mechanisms and regulation employed by enterococci to tolerate diverse stressors and highlight the role of stress tolerance in the biology of this medically relevant genus.
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7
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Latorre M, Burkhead JL, Hodar C, Arredondo M, González M, Araya M. Chronic copper treatment prevents the liver critical balance transcription response induced by acetaminophen. J Trace Elem Med Biol 2019; 53:113-119. [PMID: 30910193 DOI: 10.1016/j.jtemb.2019.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/31/2019] [Accepted: 02/17/2019] [Indexed: 02/01/2023]
Abstract
The independent toxic effects of copper and acetaminophen are among the most studied topics in liver toxicity. Here, in an animal model of Cebus capucinus chronically exposed to high dietary copper, we assessed clinical and global transcriptional adaptations of the liver induced by a single high dose of acetaminophen. The experiment conditions were chosen to resemble a close to human real-life situation of exposure to both toxic stimuli. The clinical parameters and histological analyses indicated that chronic copper administration does not induce liver damage and may have a protective effect in acetaminophen challenge. Acetaminophen administration in previously non-exposed animals induced down-regulation of a complex network of gene regulators, highlighting the putative participation of the families of gene regulators HNF, FOX, PPAR and NRF controlling this process. This gene response was not observed in animals that previously received chronic oral copper, suggesting that this metal induces a transcriptional adaptation that may protect against acetaminophen toxicity, a classical adaptation response termed preconditioning of the liver.
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Affiliation(s)
- Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile; Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Blanco Encalada 2085, Santiago, Chile; Mathomics, Center for Mathematical Modeling, Universidad de Chile, Beauchef 851, 7th Floor, Santiago, Chile; Instituto de Ciencias de la Ingeniería, Universidad de O'Higgins, Av. Viel 1497, Rancagua, Chile.
| | - Jason L Burkhead
- Department of Biological Sciences Anchorage, University of Alaska Anchorage, Anchorage, Alaska, United States
| | - Christian Hodar
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile; Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Blanco Encalada 2085, Santiago, Chile
| | - Miguel Arredondo
- Micronutrients Laboratory, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile
| | - Mauricio González
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile; Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Blanco Encalada 2085, Santiago, Chile
| | - Magdalena Araya
- Gastroenterología y Nutrición, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile.
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8
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Quesille-Villalobos AM, Parra A, Maza F, Navarrete P, González M, Latorre M, Toro M, Reyes-Jara A. The Combined Effect of Cold and Copper Stresses on the Proliferation and Transcriptional Response of Listeria monocytogenes. Front Microbiol 2019; 10:612. [PMID: 30984140 PMCID: PMC6447683 DOI: 10.3389/fmicb.2019.00612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/11/2019] [Indexed: 11/13/2022] Open
Abstract
Listeria monocytogenes is a foodborne pathogen that can cause severe disease in susceptible humans. This microorganism has the ability to adapt to hostile environmental conditions such as the low temperatures used by the food industry for controlling microorganisms. Bacteria are able to adjust their transcriptional response to adapt to stressful conditions in order to maintain cell homeostasis. Understanding the transcriptional response of L. monocytogenes to stressing conditions could be relevant to develop new strategies to control the pathogen. A possible alternative for controlling microorganisms in the food industry could be to use copper as an antimicrobial agent. The present study characterized three L. monocytogenes strains (List2-2, Apa13-2, and Al152-2A) adapted to low temperature and challenged with different copper concentrations. Similar MIC-Cu values were observed among studied strains, but growth kinetic parameters revealed that strain List2-2 was the least affected by the presence of copper at 8°C. This strain was selected for a global transcriptional response study after a 1 h exposition to 0.5 mM of CuSO4 × 5H2O at 8 and 37°C. The results showed that L. monocytogenes apparently decreases its metabolism in response to copper, and this reduction is greater at 8°C than at 37°C. The most affected metabolic pathways were carbohydrates, lipids and nucleotides synthesis. Finally, 15 genes were selected to evaluate the conservation of the transcriptional response in the other two strains. Results indicated that only genes related to copper homeostasis showed a high degree of conservation between the strains studied, suggesting that a low number of genes is implicated in the response to copper stress in L. monocytogenes. These results contribute to the understanding of the molecular mechanisms used by bacteria to overcome a combination of stresses. This study concluded that the application of copper in low concentrations in cold environments may help to control foodborne pathogens as L. monocytogenes in the industry.
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Affiliation(s)
- Ana María Quesille-Villalobos
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Angel Parra
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Felipe Maza
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Paola Navarrete
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
- Millennium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - Mauricio González
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
- FONDAP Center for Genome Regulation (CGR), Santiago, Chile
- Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile
| | - Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
- FONDAP Center for Genome Regulation (CGR), Santiago, Chile
- Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile
- Instituto de Ciencias de la Ingeniería, Universidad de O’Higgins, Rancagua, Chile
| | - Magaly Toro
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Angélica Reyes-Jara
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
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9
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Rapid serial diluting biomicrofluidic provides EC50 in minutes. MICRO AND NANO ENGINEERING 2019. [DOI: 10.1016/j.mne.2019.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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10
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Matallana-Surget S, Werner J, Wattiez R, Lebaron K, Intertaglia L, Regan C, Morris J, Teeling H, Ferrer M, Golyshin PN, Gerogiorgis D, Reilly SI, Lebaron P. Proteogenomic Analysis of Epibacterium Mobile BBCC367, a Relevant Marine Bacterium Isolated From the South Pacific Ocean. Front Microbiol 2018; 9:3125. [PMID: 30622520 PMCID: PMC6308992 DOI: 10.3389/fmicb.2018.03125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 12/03/2018] [Indexed: 12/16/2022] Open
Abstract
Epibacterium mobile BBCC367 is a marine bacterium that is common in coastal areas. It belongs to the Roseobacter clade, a widespread group in pelagic marine ecosystems. Species of the Roseobacter clade are regularly used as models to understand the evolution and physiological adaptability of generalist bacteria. E. mobile BBCC367 comprises two chromosomes and two plasmids. We used gel-free shotgun proteomics to assess its protein expression under 16 different conditions, including stress factors such as elevated temperature, nutrient limitation, high metal concentration, and UVB exposure. Comparison of the different conditions allowed us not only to retrieve almost 70% of the predicted proteins, but also to define three main protein assemblages: 584 essential core proteins, 2,144 facultative accessory proteins and 355 specific unique proteins. While the core proteome mainly exhibited proteins involved in essential functions to sustain life such as DNA, amino acids, carbohydrates, cofactors, vitamins and lipids metabolisms, the accessory and unique proteomes revealed a more specific adaptation with the expression of stress-related proteins, such as DNA repair proteins (accessory proteome), transcription regulators and a significant predominance of transporters (unique proteome). Our study provides insights into how E. mobile BBCC367 adapts to environmental changes and copes with diverse stresses.
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Affiliation(s)
- Sabine Matallana-Surget
- Division of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Johannes Werner
- Department of Biological Oceanography, Leibniz Institute of Baltic Sea Research, Rostock, Germany
| | - Ruddy Wattiez
- Department of Proteomics and Microbiology, Interdisciplinary Mass Spectrometry Center (CISMa), University of Mons, Mons, Belgium
| | - Karine Lebaron
- Division of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Laurent Intertaglia
- Sorbonne Universites, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique, Banyuls/Mer, France.,Sorbonne Universites, UPMC Univ Paris 06, CNRS, Observatoire Océanologique de Banyuls (OOB), Banyuls/Mer, France
| | - Callum Regan
- Division of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - James Morris
- Division of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Hanno Teeling
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Manuel Ferrer
- Department of Applied Biocatalysis, Institute of Catalysis, CSIC, Madrid, Spain
| | - Peter N Golyshin
- School of Natural Sciences, University of Bangor, Bangor, United Kingdom
| | - Dimitrios Gerogiorgis
- Institute for Materials and Processes, School of Engineering, University of Edinburgh, The King's Buildings, Edinburgh, United Kingdom
| | - Simon I Reilly
- School of Natural Sciences, University of Bangor, Bangor, United Kingdom
| | - Philippe Lebaron
- Sorbonne Universites, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique, Banyuls/Mer, France.,Sorbonne Universites, UPMC Univ Paris 06, CNRS, Observatoire Océanologique de Banyuls (OOB), Banyuls/Mer, France
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11
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Latorre M, Quenti D, Travisany D, Singh KV, Murray BE, Maass A, Cambiazo V. The Role of Fur in the Transcriptional and Iron Homeostatic Response of Enterococcus faecalis. Front Microbiol 2018; 9:1580. [PMID: 30065712 PMCID: PMC6056675 DOI: 10.3389/fmicb.2018.01580] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/25/2018] [Indexed: 01/23/2023] Open
Abstract
The ferric uptake regulator (Fur) plays a major role in controlling the expression of iron homeostasis genes in bacterial organisms. In this work, we fully characterized the capacity of Fur to reconfigure the global transcriptional network and influence iron homeostasis in Enterococcus faecalis. The characterization of the Fur regulon from E. faecalis indicated that this protein (Fur) regulated the expression of genes involved in iron uptake systems, conferring to the system a high level of efficiency and specificity to respond under different iron exposure conditions. An RNAseq assay coupled with a systems biology approach allowed us to identify the first global transcriptional network activated by different iron treatments (excess and limited), with and without the presence of Fur. The results showed that changes in iron availability activated a complex network of transcriptional factors in E. faecalis, among them global regulators such as LysR, ArgR, GalRS, and local regulators, LexA and CopY, which were also stimulated by copper and zinc treatments. The deletion of Fur impacted the expression of genes encoding for ABC transporters, energy production and [Fe-S] proteins, which optimized detoxification and iron uptake under iron excess and limitation, respectively. Finally, considering the close relationship between iron homeostasis and pathogenesis, our data showed that the absence of Fur increased the internal concentration of iron in the bacterium and also affected its ability to produce biofilm. These results open new alternatives in the field of infection mechanisms of E. faecalis.
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Affiliation(s)
- Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile.,Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile.,Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Santiago, Chile.,Instituto de Ciencias de la Ingeniería, Universidad de O'Higgins, Rancagua, Chile
| | - Daniela Quenti
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile
| | - Dante Travisany
- Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile.,Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Santiago, Chile
| | - Kavindra V Singh
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth), Houston, TX, United States
| | - Barbara E Murray
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth), Houston, TX, United States
| | - Alejandro Maass
- Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile.,Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Santiago, Chile.,Department of Mathematical Engineering, Universidad de Chile, Santiago, Chile
| | - Verónica Cambiazo
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile.,Center for Genome Regulation (Fondap 15090007), Universidad de Chile, Santiago, Chile
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12
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Chalansonnet V, Mercier C, Orenga S, Gilbert C. Identification of Enterococcus faecalis enzymes with azoreductases and/or nitroreductase activity. BMC Microbiol 2017; 17:126. [PMID: 28545445 PMCID: PMC5445473 DOI: 10.1186/s12866-017-1033-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/15/2017] [Indexed: 01/03/2023] Open
Abstract
Background Nitroreductases, NAD(P)H dependent flavoenzymes, are found in most of bacterial species. Even if Enterococcus faecalis strains seems to present such activity because of their sensitivity to nitrofurans, no enzyme has been described. Nitroreductases were separated of others reductases due to their capacity to reduce nitro compounds. They are further classified based on their preference in cofactor: NADH and/or NADPH. However, recently, azoreductases have been studied for their strong activity on nitro compounds, especially nitro pro-drugs. This result suggests a crossing in azo and nitro reductase activities. For the moment, no nitroreductase was demonstrated to possess azoreductase activity. But due to sequence divergence and activity specificity linked to substrates, activity prediction is not evident and biochemical characterisation remains necessary. Identifying enzymes active on these two classes of compounds: azo and nitro is of interest to consider a common physiological role. Results Four putative nitroreductases, EF0404, EF0648, EF0655 and EF1181 from Enterococcus faecalis V583 were overexpressed as his-tagged recombinant proteins in Escherichia coli and purified following a native or a denaturing/renaturing protocol. EF0648, EF0655 and EF1181 showed nitroreductase activity and their cofactor preferences were in agreement with their protein sequence phylogeny. EF0404 showed both nitroreductase and azoreductase activity. Interestingly, the biochemical characteristics (substrate and cofactor specificity) of EF0404 resembled the properties of the known azoreductase AzoA. But its sequence matched within nitroreductase group, the same as EF0648. Conclusions We here demonstrate nitroreductase activity of the putative reductases identified in the Enterococcus faecalis V583 genome. We identified the first nitroreductase able to reduce directly an azo compound, while its protein sequence is close to others nitroreductases. Consequently, it highlights the difficulty in classifying these enzymes solely on the basis of protein sequence alignment and hereby the necessity to experimentally demonstrate the activity. The results provide additional data to consider a broader functionality of these reductases.
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Affiliation(s)
- Valérie Chalansonnet
- bioMérieux, 3 route de port Michaud, 38390, La Balme les Grottes, France. .,CIRI, International Center for Infectiology Research, Legionella pathogenesis group, Université de Lyon, Lyon, France. .,INSERM, U1111, Lyon, France. .,Ecole Normale Supérieure de Lyon, F-69364, Lyon, France. .,Université Lyon 1, F-69622, Lyon, France. .,CNRS, UMR5308, Lyon, France.
| | - Claire Mercier
- bioMérieux, 3 route de port Michaud, 38390, La Balme les Grottes, France.,CIRI, International Center for Infectiology Research, Legionella pathogenesis group, Université de Lyon, Lyon, France.,INSERM, U1111, Lyon, France.,Ecole Normale Supérieure de Lyon, F-69364, Lyon, France.,Université Lyon 1, F-69622, Lyon, France.,CNRS, UMR5308, Lyon, France
| | - Sylvain Orenga
- bioMérieux, 3 route de port Michaud, 38390, La Balme les Grottes, France
| | - Christophe Gilbert
- CIRI, International Center for Infectiology Research, Legionella pathogenesis group, Université de Lyon, Lyon, France.,INSERM, U1111, Lyon, France.,Ecole Normale Supérieure de Lyon, F-69364, Lyon, France.,Université Lyon 1, F-69622, Lyon, France.,CNRS, UMR5308, Lyon, France
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Del Pozo T, Gutiérrez-Garcia R, Latorre M, González M, Suazo M. Identification of reference genes for quantitative real-time PCR studies in human cell lines under copper and zinc exposure. Biometals 2016; 29:935-44. [PMID: 27567902 DOI: 10.1007/s10534-016-9965-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 07/31/2016] [Indexed: 12/18/2022]
Abstract
Accurate quantification depends on normalization of the measured gene expression data. In particular, gene expression studies with exposure to metals are challenging due their toxicity and redox-active properties. Here, we assessed the stability of potential reference genes in three cell lines commonly used to study metal cell metabolism: Caco-2 (colon), HepG2 (liver) and THP-1 (peripheral blood) under copper (Cu) or zinc (Zn) exposure. We used combined statistical tools to identify the best reference genes from a set of eleven candidates, which included traditional "housekeeping" genes such as GAPDH and B-ACTIN, in cell lines exposed to high and low, Zn and Cu concentrations. The expression stabilities of ATP5B (ATP synthase) and CYC1 (subunits of the cytochrome) were the highest considering the effect of Zn and Cu treatments whereas SDHA (succinate dehydrogenase) was found to be the most unstable gene. Even though the transcriptional effect of Zn and Cu is very different in term of redox properties, the same best reference genes were identified when Zn or Cu treatments were analyzed together. Our results indicate that ATP5B/CYC1 are the best candidates for reference genes after metal exposure, which can be used as a suitable starting point to evaluate gene expression with other metals or in different cell types in human models.
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Affiliation(s)
- Talía Del Pozo
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile.
| | - Ricardo Gutiérrez-Garcia
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile.
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
| | - Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile
- Center for Genome Regulation, Universidad de Chile, Santiago, Chile
- Mathomics, Center for Mathematical Modeling, Universidad de Chile, Santiago, Chile
| | - Mauricio González
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile
- Center for Genome Regulation, Universidad de Chile, Santiago, Chile
| | - Miriam Suazo
- Nutrition and Dietetics, Faculty of Health Sciences, San Sebastian University, Valdivia, Chile
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Abstract
Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance.
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15
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Cordero N, Maza F, Navea-Perez H, Aravena A, Marquez-Fontt B, Navarrete P, Figueroa G, González M, Latorre M, Reyes-Jara A. Different Transcriptional Responses from Slow and Fast Growth Rate Strains of Listeria monocytogenes Adapted to Low Temperature. Front Microbiol 2016; 7:229. [PMID: 26973610 PMCID: PMC4772535 DOI: 10.3389/fmicb.2016.00229] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 02/12/2016] [Indexed: 01/12/2023] Open
Abstract
Listeria monocytogenes has become one of the principal foodborne pathogens worldwide. The capacity of this bacterium to grow at low temperatures has opened an interesting field of study in terms of the identification and classification of new strains of L. monocytogenes with different growth capacities at low temperatures. We determined the growth rate at 8°C of 110 strains of L. monocytogenes isolated from different food matrices. We identified a group of slow and fast strains according to their growth rate at 8°C and performed a global transcriptomic assay in strains previously adapted to low temperature. We then identified shared and specific transcriptional mechanisms, metabolic and cellular processes of both groups; bacterial motility was the principal process capable of differentiating the adaptation capacity of L. monocytogenes strains with different ranges of tolerance to low temperatures. Strains belonging to the fast group were less motile, which may allow these strains to achieve a greater rate of proliferation at low temperature.
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Affiliation(s)
- Ninoska Cordero
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Felipe Maza
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Helen Navea-Perez
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Andrés Aravena
- Department of Molecular Biology and Genetics, Istanbul University Istanbul, Turkey
| | - Bárbara Marquez-Fontt
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Paola Navarrete
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Guillermo Figueroa
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
| | - Mauricio González
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de ChileSantiago, Chile; Center for Genome Regulation (Fondap 15090007), Universidad de ChileSantiago, Chile
| | - Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de ChileSantiago, Chile; Center for Genome Regulation (Fondap 15090007), Universidad de ChileSantiago, Chile; Mathomics, Center for Mathematical Modeling, Universidad de ChileSantiago, Chile
| | - Angélica Reyes-Jara
- Laboratorio de Microbiología y Probióticos, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile Santiago, Chile
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Latorre M, Quesille-Villalobos AM, Maza F, Parra A, Reyes-Jara A. Synergistic effect of copper and low temperature over Listeria monocytogenes. Biometals 2015; 28:1087-92. [PMID: 26515293 DOI: 10.1007/s10534-015-9891-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 10/26/2015] [Indexed: 10/22/2022]
Abstract
The capacity to grow at low temperatures has allowed Listeria monocytogenes to become one of the primary food pathogens to date, representing a major public health problem worldwide. Several works have described the homeostatic response of L. monocytogenes under different copper (Cu) treatments growing at mild temperature (30 °C). The aims of this report were to evaluate if changes in the external concentration of Cu affected viability and Cu homeostasis of L. monocytogenes growing at low temperature. Ours results showed that L. monocytogenes growing at 8 °C had a reduced viability relative to 30 °C when exposed to Cu treatments. This decrease was correlated with an increase in the internal concentration of Cu, probably linked to the transcriptional down-regulation of mechanisms involved in Cu homeostasis. This combined effect of Cu and low temperature showed a synergistic impact over the viability and homeostasis of L. monocytogenes, where low temperature exacerbated the toxic effect of Cu. These results can be useful in terms of the use of Cu as an antibacterial agent.
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Affiliation(s)
- Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile.,Center of Genome Regulation (Fondap 15090007), Universidad de Chile, Blanco Encalada 2085, Santiago, Chile.,Mathomics, Center for Mathematical Modeling, Universidad de Chile, Beauchef 851, 6th Floor, Santiago, Chile.,Center of Mathematical Modeling, Universidad de Chile, Beauchef 851, Santiago, Chile
| | | | - Felipe Maza
- Laboratorio de Microbiología y Probióticos, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile
| | - Angel Parra
- Laboratorio de Microbiología y Probióticos, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile
| | - Angélica Reyes-Jara
- Laboratorio de Microbiología y Probióticos, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile.
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Santiago AS, Santos CA, Mendes JS, Toledo MAS, Beloti LL, Souza AA, Souza AP. Characterization of the LysR-type transcriptional regulator YcjZ-like from Xylella fastidiosa overexpressed in Escherichia coli. Protein Expr Purif 2015; 113:72-8. [PMID: 25979465 DOI: 10.1016/j.pep.2015.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 05/04/2015] [Accepted: 05/06/2015] [Indexed: 11/20/2022]
Abstract
The Xylella fastidiosa 9a5c strain is a xylem-limited phytopathogen that is the causal agent of citrus variegated chlorosis (CVC). This bacterium is able to form a biofilm and occlude the xylem vessels of susceptible plants, which leads to significant agricultural and economic losses. Biofilms are associated with bacterial pathogenicity because they are very resistant to antibiotics and other metal-based chemicals that are used in agriculture. The X. fastidiosa YcjZ-like (XfYcjZ-like) protein belongs to the LysR-type transcriptional regulator (LTTR) family and is involved in various cellular functions that range from quorum sensing to bacterial survival. In the present study, we report the cloning, expression and purification of XfYcjZ-like, which was overexpressed in Escherichia coli. The secondary folding of the recombinant and purified protein was assessed by circular dichroism, which revealed that XfYcjZ-like contains a typical α/β fold. An initial hydrodynamic characterization showed that XfYcjZ-like is a globular tetramer in solution. In addition, using a polyclonal antibody against XfYcjZ-like, we assessed the expression profile of this protein during the different developmental phases of X. fastidiosa in in vitro cultivated biofilm cells and demonstrated that XfYcjZ-like is upregulated in planktonic cells in response to a copper shock treatment. Finally, the ability of XfYcjZ-like to interact with its own predicted promoter was confirmed in vitro, which is a typical feature of LysR. Taken together, our findings indicated that the XfYcjZ-like protein is involved in both the organization of the architecture and the maturation of the bacterial biofilm and that it is responsive to oxidative stress.
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Affiliation(s)
- André S Santiago
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Clelton A Santos
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Juliano S Mendes
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Marcelo A S Toledo
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Lilian L Beloti
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Alessandra A Souza
- Centro APTA Citros Sylvio Moreira/IAC, Rodovia Anhanguera Km 158, Cordeirópolis, SP, Brazil
| | - Anete P Souza
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas, Campinas, SP, Brazil; Departamento de Biologia Vegetal, Instituto de Biologia (IB), Universidade Estadual de Campinas, Campinas, SP, Brazil.
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Latorre M, Low M, Gárate E, Reyes-Jara A, Murray BE, Cambiazo V, González M. Interplay between copper and zinc homeostasis through the transcriptional regulator Zur in Enterococcus faecalis. Metallomics 2015; 7:1137-45. [PMID: 25906431 DOI: 10.1039/c5mt00043b] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
By integrating the microarray expression data and a global E. faecalis transcriptional network we identified a sub-network activated by zinc and copper. Our analyses indicated that the transcriptional response of the bacterium to copper and zinc exposure involved the activation of two modules, module I that contains genes implicated in zinc homeostasis, including the Zur transcriptional repressor, and module II containing a set of genes associated with general stress response and basal metabolism. Bacterial exposure to zinc and copper led to the repression of the zinc uptake systems of module I. Upon deletion of Zur, exposure to different zinc and copper conditions induced complementary homeostatic mechanisms (ATPase efflux proteins) to control the intracellular concentrations of zinc. The transcriptional activation of zinc homeostasis genes by zinc and copper reveals a functional interplay between these two metals, in which exposure to copper also impacts on the zinc homeostasis. Finally, we present a new zinc homeostasis model in E. faecalis, positioning this bacterium as one of the most complete systems biology model in metals described to date.
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Affiliation(s)
- Mauricio Latorre
- Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, El Líbano 5524, Macul, Santiago, Chile.
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Quiroz N, Rivas N, del Pozo T, Burkhead J, Suazo M, González M, Latorre M. Transcriptional activation of glutathione pathways and role of glucose homeostasis during copper imbalance. Biometals 2015; 28:321-8. [DOI: 10.1007/s10534-015-9834-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Accepted: 02/05/2015] [Indexed: 12/18/2022]
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