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Fernández-Otal Á, Guío J, Sarasa-Buisan C, Peleato ML, Fillat MF, Lanas Á, Bes MT. Functional characterization of Fur from the strict anaerobe Clostridioides difficile provides insight into its redox-driven regulatory capacity. FEBS J 2024; 291:3604-3627. [PMID: 38775144 DOI: 10.1111/febs.17156] [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: 12/01/2023] [Revised: 02/06/2024] [Accepted: 04/29/2024] [Indexed: 08/15/2024]
Abstract
Clostridioides (formerly Clostridium) difficile is a leading cause of infectious diarrhea associated with antibiotic therapy. The ability of this anaerobic pathogen to acquire enough iron to proliferate under iron limitation conditions imposed by the host largely determines its pathogenicity. However, since high intracellular iron catalyzes formation of deleterious reactive hydroxyl radicals, iron uptake is tightly regulated at the transcriptional level by the ferric uptake regulator Fur. Several studies relate lacking a functional fur gene in C. difficile cells to higher oxidative stress sensitivity, colonization defect and less toxigenicity, although Fur does not appear to directly regulate either oxidative stress response genes or pathogenesis genes. In this work, we report the functional characterization of C. difficile Fur and describe an additional oxidation sensing Fur-mediated mechanism independent of iron, which affects Fur DNA-binding. Using electrophoretic mobility shift assays, we show that Fur binding to the promoters of fur, feoA and fldX genes, identified as iron and Fur-regulated genes in vivo, is specific and does not require co-regulator metal under reducing conditions. Fur treatment with H2O2 produces dose-dependent soluble high molecular weight species unable to bind to target promoters. Moreover, Fur oligomers are dithiotreitol sensitive, highlighting the importance of some interchain disulfide bond(s) for Fur oligomerization, and hence for activity. Additionally, the physiological electron transport chain NADPH-thioredoxin reductase/thioredoxin from Escherichia coli reduces inactive oligomerized C. difficile Fur that recovers activity. In conjunction with available transcriptomic data, these results suggest a previously underappreciated complexity in the control of some members of the Fur regulon that is based on Fur redox properties and might be fundamental for the adaptive response of C. difficile during infection.
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Affiliation(s)
- Ángela Fernández-Otal
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain
| | - Jorge Guío
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
| | - Cristina Sarasa-Buisan
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
| | - M Luisa Peleato
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
| | - María F Fillat
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
| | - Ángel Lanas
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain
- Digestive Diseases Service, University Clinic Hospital Lozano Blesa, Zaragoza, Spain
- CIBERehd, Madrid, Spain
| | - M Teresa Bes
- Department of Biochemistry & Molecular and Cellular Biology, University of Zaragoza, Spain
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Mariano Esquillor (Edif. I+D), Zaragoza, Spain
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2
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Zhang R, Bu Y, Zhang Y, Choi SH, Wang Q, Ma Y, Shao S. Fur-mediated regulation of hydrogen sulfide synthesis, stress response, and virulence in Edwardsiella piscicida. Microbiol Res 2024; 284:127735. [PMID: 38678681 DOI: 10.1016/j.micres.2024.127735] [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: 03/24/2024] [Revised: 04/12/2024] [Accepted: 04/19/2024] [Indexed: 05/01/2024]
Abstract
The production of endogenous hydrogen sulfide (H2S) is an important phenotype of bacteria. H2S plays an important role in bacterial resistance to ROS and antibiotics, which significantly contributes to bacterial pathogenicity. Edwardsiella piscicida, the Gram-negative pathogen causing fish edwardsiellosis, has been documented to produce hydrogen sulfide. In the study, we revealed that Ferric uptake regulator (Fur) controlled H2S synthesis by activating the expression of phsABC operon. Besides, Fur participated in the bacterial defense against ROS and cationic antimicrobial peptides and modulated T3SS expression. Furthermore, the disruption of fur exhibited a significant in vivo colonization defect. Collectively, our study demonstrated the regulation of Fur in H2S synthesis, stress response, and virulence, providing a new perspective for better understanding the pathogenesis of Edwardsiella.
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Affiliation(s)
- Riyu Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yifan Bu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yuanxing Zhang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China; Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai, China
| | - Sang Ho Choi
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Qiyao Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China; Shanghai Haosi Marine Biotechnology Co., Ltd, China
| | - Yue Ma
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai, China; Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China.
| | - Shuai Shao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai, China; Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China.
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3
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Hu C, Garey KW. Microscopy methods for Clostridioides difficile. Anaerobe 2024; 86:102822. [PMID: 38341023 DOI: 10.1016/j.anaerobe.2024.102822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
Microscopic technologies including light and fluorescent, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and cryo-electron microscopy have been widely utilized to visualize Clostridioides difficile at the molecular, cellular, community, and structural biology level. This comprehensive review summarizes the microscopy tools (fluorescent and reporter system) in their use to study different aspects of C. difficile life cycle and virulence (sporulation, germination) or applications (detection of C. difficile or use of antimicrobials). With these developing techniques, microscopy tools will be able to find broader applications and address more challenging questions to study C. difficile and C. difficile infection.
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Affiliation(s)
- Chenlin Hu
- University of Houston College of Pharmacy, Houston, TX, USA
| | - Kevin W Garey
- University of Houston College of Pharmacy, Houston, TX, USA.
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4
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Troitzsch D, Knop R, Dittmann S, Bartel J, Zühlke D, Möller TA, Trän L, Echelmeyer T, Sievers S. Characterizing the flavodoxin landscape in Clostridioides difficile. Microbiol Spectr 2024; 12:e0189523. [PMID: 38319052 PMCID: PMC10913485 DOI: 10.1128/spectrum.01895-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 12/23/2023] [Indexed: 02/07/2024] Open
Abstract
Clostridioides difficile infections have become a major challenge in medical facilities. The bacterium is capable of spore formation allowing the survival of antibiotic treatment. Therefore, research on the physiology of C. difficile is important for the development of alternative treatment strategies. In this study, we investigated eight putative flavodoxins of C. difficile 630. Flavodoxins are small electron transfer proteins of specifically low potential. The unusually high number of flavodoxins in C. difficile suggests that they are expressed under different conditions. We determined high transcription levels for several flavodoxins during the exponential growth phase, especially for floX. Since flavodoxins are capable of replacing ferredoxins under iron deficiency conditions in other bacteria, we also examined their expression in C. difficile under low iron and no iron levels. In particular, the amount of fldX increased with decreasing iron concentration and thus could possibly replace ferredoxins. Moreover, we demonstrated that fldX is increasingly expressed under different oxidative stress conditions and thus may play an important role in the oxidative stress response. While increased fldX expression was detectable at both RNA and protein level, CD2825 showed increased expression only at mRNA level under H2O2 stress with sufficient iron availability and may indicate hydroxyl radical-dependent transcription. Although the exact function of the individual flavodoxins in C. difficile needs to be further investigated, the present study shows that flavodoxins could play an important role in several physiological processes and under infection-relevant conditions. IMPORTANCE The gram-positive, anaerobic, and spore-forming bacterium Clostridioides difficile has become a vast problem in human health care facilities. The antibiotic-associated infection with this intestinal pathogen causes serious and recurrent inflammation of the intestinal epithelium, in many cases with a severe course. To come up with novel targeted therapies against C. difficile infections, a more detailed knowledge on the pathogen's physiology is mandatory. Eight putative flavodoxins, an extraordinarily high copy number of this type of small electron transfer proteins, are annotated for C. difficile. Flavodoxins are known to be essential electron carriers in other bacteria, for instance, during infection-relevant conditions such as iron limitation and oxidative stress. This work is a first and comprehensive overview on characteristics and expression profiles of the putative flavodoxins in the pathogen C. difficile.
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Affiliation(s)
- Daniel Troitzsch
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Robert Knop
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Silvia Dittmann
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Jürgen Bartel
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Daniela Zühlke
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Timon Alexander Möller
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Linda Trän
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Thaddäus Echelmeyer
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Susanne Sievers
- Department of Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
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5
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Mridha S, Abt MC. Starvation helps transition to abundance - a ferrosome story. Trends Microbiol 2024; 32:219-220. [PMID: 38281864 DOI: 10.1016/j.tim.2024.01.006] [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: 01/05/2024] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 01/30/2024]
Abstract
Iron is an essential nutrient for bacterial pathogenesis. In their study, Skaar and colleagues (Pi et al.) discovered and determined the detailed structure of ferrosomes within Clostridioides difficile, the iron-storage organelles that form under iron-limited conditions in anticipation of future iron overload.
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Affiliation(s)
- Subham Mridha
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael C Abt
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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6
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Marvaud JC, Bouttier S, Saunier J, Kansau I. Clostridioides difficile Flagella. Int J Mol Sci 2024; 25:2202. [PMID: 38396876 PMCID: PMC10889297 DOI: 10.3390/ijms25042202] [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: 01/16/2024] [Revised: 02/04/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Clostridioides difficile is an important pathogen for humans with a lead in nosocomial infection, but it is also more and more common in communities. Our knowledge of the pathology has historically been focused on the toxins produced by the bacteria that remain its major virulence factors. But the dysbiosis of the intestinal microbiota creating the conditions for the colonization appears to be fundamental for our understanding of the disease. Colonization implies several steps for the bacteria that do or do not use their capacity of motility with the synthesis of flagella. In this review, we focus on the current understanding of different topics on the C. difficile flagellum, ranging from its genetic organization to the vaccinal interest in it.
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Affiliation(s)
- Jean-Christophe Marvaud
- Institut MICALIS, INRAE, AgroParisTech, Equipe Bactéries Pathogènes et Santé, Faculté de Pharmacie, Université Paris-Saclay, 91400 Orsay, France (I.K.)
| | - Sylvie Bouttier
- Institut MICALIS, INRAE, AgroParisTech, Equipe Bactéries Pathogènes et Santé, Faculté de Pharmacie, Université Paris-Saclay, 91400 Orsay, France (I.K.)
| | - Johanna Saunier
- Matériaux et Santé, Faculté de pharmacie, Université Paris Saclay, 91400 Orsay, France
| | - Imad Kansau
- Institut MICALIS, INRAE, AgroParisTech, Equipe Bactéries Pathogènes et Santé, Faculté de Pharmacie, Université Paris-Saclay, 91400 Orsay, France (I.K.)
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7
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Verstraeten S, Layec S, Auger S, Juste C, Henry C, Charif S, Jaszczyszyn Y, Sokol H, Beney L, Langella P, Thomas M, Huillet E. Faecalibacterium duncaniae A2-165 regulates the expression of butyrate synthesis, ferrous iron uptake, and stress-response genes based on acetate consumption. Sci Rep 2024; 14:987. [PMID: 38200051 PMCID: PMC10781979 DOI: 10.1038/s41598-023-51059-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 12/29/2023] [Indexed: 01/12/2024] Open
Abstract
The promising next-generation probiotic Faecalibacterium prausnitzii is one of the most abundant acetate-consuming, butyrate-producing bacteria in the healthy human gut. Yet, little is known about how acetate availability affects this bacterium's gene expression strategies. Here, we investigated the effect of acetate on temporal changes in the transcriptome of F. duncaniae A2-165 cultures using RNA sequencing. We compared gene expression patterns between two growth phases (early stationary vs. late exponential) and two acetate levels (low: 3 mM vs. high: 23 mM). Only in low-acetate conditions, a general stress response was activated. In high-acetate conditions, there was greater expression of genes related to butyrate synthesis and to the importation of B vitamins and iron. Specifically, expression was strongly activated in the case of the feoAABC operon, which encodes a FeoB ferrous iron transporter, but not in the case of the feoAB gene, which encodes a second putative FeoAB transporter. Moreover, excess ferrous iron repressed feoB expression but not feoAB. Lastly, FeoB but not FeoAB peptides from strain A2-165 were found in abundance in a healthy human fecal metaproteome. In conclusion, we characterized two early-stationary transcriptomes based on acetate consumption and this work highlights the regulation of feoB expression in F. duncaniae A2-165.
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Affiliation(s)
- Sophie Verstraeten
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Séverine Layec
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Sandrine Auger
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- Paris Center for Microbiome Medecine (PaCeMM) FHU, AP-HP, Paris, France
| | - Catherine Juste
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Céline Henry
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Sawiya Charif
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Yan Jaszczyszyn
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, Gif-Sur-Yvette, France
| | - Harry Sokol
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- Paris Center for Microbiome Medecine (PaCeMM) FHU, AP-HP, Paris, France
| | - Laurent Beney
- UMR PAM, INRAe, Université Bourgogne Franche-Conté, AgroSup Dijon, Dijon, France
| | - Philippe Langella
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- Paris Center for Microbiome Medecine (PaCeMM) FHU, AP-HP, Paris, France
| | - Muriel Thomas
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- Paris Center for Microbiome Medecine (PaCeMM) FHU, AP-HP, Paris, France
| | - Eugénie Huillet
- Micalis Institute, INRAe, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.
- Paris Center for Microbiome Medecine (PaCeMM) FHU, AP-HP, Paris, France.
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8
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Hastie JL, Carmichael HL, Werner BM, Dunbar KE, Carlson PE. Clostridioides difficile utilizes siderophores as an iron source and FhuDBGC contributes to ferrichrome uptake. J Bacteriol 2023; 205:e0032423. [PMID: 37971230 PMCID: PMC10729759 DOI: 10.1128/jb.00324-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 10/26/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE This study is the first example of C. difficile growing with siderophores as the sole iron source and describes the characterization of the ferric hydroxamate uptake ABC transporter (FhuDBGC). This transporter shows specificity to the siderophore ferrichrome. While not required for pathogenesis, this transporter highlights the redundancy in iron acquisition mechanisms that C. difficile uses to compete for iron during an infection.
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Affiliation(s)
- Jessica L. Hastie
- Food and Drug Administration, Center for Biologics Evaluation and Research, Office of Vaccines Research and Review, Division of Bacterial Parasitic and Allergenic Products, Laboratory of Mucosal Pathogens and Cellular Immunology, Silver Spring, Maryland, USA
| | - Hannah L. Carmichael
- Food and Drug Administration, Center for Biologics Evaluation and Research, Office of Vaccines Research and Review, Division of Bacterial Parasitic and Allergenic Products, Laboratory of Mucosal Pathogens and Cellular Immunology, Silver Spring, Maryland, USA
| | - Bailey M. Werner
- Food and Drug Administration, Center for Biologics Evaluation and Research, Office of Vaccines Research and Review, Division of Bacterial Parasitic and Allergenic Products, Laboratory of Mucosal Pathogens and Cellular Immunology, Silver Spring, Maryland, USA
| | - Kristin E. Dunbar
- Food and Drug Administration, Center for Biologics Evaluation and Research, Office of Vaccines Research and Review, Division of Bacterial Parasitic and Allergenic Products, Laboratory of Mucosal Pathogens and Cellular Immunology, Silver Spring, Maryland, USA
| | - Paul E. Carlson
- Food and Drug Administration, Center for Biologics Evaluation and Research, Office of Vaccines Research and Review, Division of Bacterial Parasitic and Allergenic Products, Laboratory of Mucosal Pathogens and Cellular Immunology, Silver Spring, Maryland, USA
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9
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Lacotte PA, Denis-Quanquin S, Chatonnat E, Le Bris J, Leparfait D, Lequeux T, Martin-Verstraete I, Candela T. The absence of surface D-alanylation, localized on lipoteichoic acid, impacts the Clostridioides difficile way of life and antibiotic resistance. Front Microbiol 2023; 14:1267662. [PMID: 37965542 PMCID: PMC10642750 DOI: 10.3389/fmicb.2023.1267662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 10/13/2023] [Indexed: 11/16/2023] Open
Abstract
Introduction The dlt operon encodes proteins responsible for the esterification of positively charged D-alanine on the wall teichoic acids and lipoteichoic acids of Gram-positive bacteria. This structural modification of the bacterial anionic surface in several species has been described to alter the physicochemical properties of the cell-wall. In addition, it has been linked to reduced sensibilities to cationic antimicrobial peptides and antibiotics. Methods We studied the D-alanylation of Clostridioides difficile polysaccharides with a complete deletion of the dltDABCoperon in the 630 strain. To look for D-alanylation location, surface polysaccharides were purified and analyzed by NMR. Properties of the dltDABCmutant and the parental strains, were determined for bacterial surface's hydrophobicity, motility, adhesion, antibiotic resistance. Results We first confirmed the role of the dltDABCoperon in D-alanylation. Then, we established the exclusive esterification of D-alanine on C. difficile lipoteichoic acid. Our data also suggest that D-alanylation modifies the cell-wall's properties, affecting the bacterial surface's hydrophobicity, motility, adhesion to biotic and abiotic surfaces,and biofilm formation. In addition, our mutant exhibitedincreased sensibilities to antibiotics linked to the membrane, especially bacitracin. A specific inhibitor DLT-1 of DltA reduces the D-alanylation rate in C. difficile but the inhibition was not sufficient to decrease the antibiotic resistance against bacitracin and vancomycin. Conclusion Our results suggest the D-alanylation of C. difficile as an interesting target to tackle C. difficile infections.
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Affiliation(s)
- Pierre-Alexandre Lacotte
- Micalis Institute, Université Paris-Saclay, INRAE AgroParisTech, Jouy-en-Josas, France
- Institut Pasteur, Université Paris Cité, UMR6047 CNRS, Laboratoire Pathogenèse des Bactéries Anaérobies, Paris, France
| | | | - Eva Chatonnat
- Institut Pasteur, Université Paris Cité, UMR6047 CNRS, Laboratoire Pathogenèse des Bactéries Anaérobies, Paris, France
| | - Julie Le Bris
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS UMR3525, Université Paris Cité, Paris, France
| | - David Leparfait
- Normandie Université, Laboratoire de Chimie Moléculaire et Thioorganique LCMT UMR6507, ENSICAEN, UNICAEN, CNRS, Caen, France
| | - Thierry Lequeux
- Normandie Université, Laboratoire de Chimie Moléculaire et Thioorganique LCMT UMR6507, ENSICAEN, UNICAEN, CNRS, Caen, France
| | - Isabelle Martin-Verstraete
- Institut Pasteur, Université Paris Cité, UMR6047 CNRS, Laboratoire Pathogenèse des Bactéries Anaérobies, Paris, France
- Institut Universitaire de France, Paris, France
| | - Thomas Candela
- Micalis Institute, Université Paris-Saclay, INRAE AgroParisTech, Jouy-en-Josas, France
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10
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Rizvi A, Vargas-Cuebas G, Edwards AN, DiCandia MA, Carter ZA, Lee CD, Monteiro MP, McBride SM. Glycine fermentation by C. difficile promotes virulence and spore formation, and is induced by host cathelicidin. Infect Immun 2023; 91:e0031923. [PMID: 37754683 PMCID: PMC10580938 DOI: 10.1128/iai.00319-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 09/28/2023] Open
Abstract
Clostridioides difficile is a leading cause of antibiotic-associated diarrheal disease. C. difficile colonization, growth, and toxin production in the intestine is strongly associated with its ability to use amino acids to generate energy, but little is known about the impact of specific amino acids on C. difficile pathogenesis. The amino acid glycine is enriched in the dysbiotic gut and is suspected to contribute to C. difficile infection. We hypothesized that the use of glycine as an energy source contributes to colonization of the intestine and pathogenesis of C. difficile. To test this hypothesis, we deleted the glycine reductase (GR) genes grdAB, rendering C. difficile unable to ferment glycine, and investigated the impact on growth and pathogenesis. Our data show that the grd pathway promotes growth, toxin production, and sporulation. Glycine fermentation also had a significant impact on toxin production and pathogenesis of C. difficile in the hamster model of disease. Furthermore, we determined that the grd locus is regulated by host cathelicidin (LL-37) and the cathelicidin-responsive regulator, ClnR, indicating that the host peptide signals to control glycine catabolism. The induction of glycine fermentation by LL-37 demonstrates a direct link between the host immune response and the bacterial reactions of toxin production and spore formation.
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Affiliation(s)
- Arshad Rizvi
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Germán Vargas-Cuebas
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Adrianne N. Edwards
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Michael A. DiCandia
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Zavier A. Carter
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Cheyenne D. Lee
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Marcos P. Monteiro
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Shonna M. McBride
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
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11
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Dicks LMT. Biofilm Formation of Clostridioides difficile, Toxin Production and Alternatives to Conventional Antibiotics in the Treatment of CDI. Microorganisms 2023; 11:2161. [PMID: 37764005 PMCID: PMC10534356 DOI: 10.3390/microorganisms11092161] [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: 06/29/2023] [Revised: 08/16/2023] [Accepted: 08/24/2023] [Indexed: 09/29/2023] Open
Abstract
Clostridioides difficile is considered a nosocomial pathogen that flares up in patients exposed to antibiotic treatment. However, four out of ten patients diagnosed with C. difficile infection (CDI) acquired the infection from non-hospitalized individuals, many of whom have not been treated with antibiotics. Treatment of recurrent CDI (rCDI) with antibiotics, especially vancomycin (VAN) and metronidazole (MNZ), increases the risk of experiencing a relapse by as much as 70%. Fidaxomicin, on the other hand, proved more effective than VAN and MNZ by preventing the initial transcription of RNA toxin genes. Alternative forms of treatment include quorum quenching (QQ) that blocks toxin synthesis, binding of small anion molecules such as tolevamer to toxins, monoclonal antibodies, such as bezlotoxumab and actoxumab, bacteriophage therapy, probiotics, and fecal microbial transplants (FMTs). This review summarizes factors that affect the colonization of C. difficile and the pathogenicity of toxins TcdA and TcdB. The different approaches experimented with in the destruction of C. difficile and treatment of CDI are evaluated.
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Affiliation(s)
- Leon M T Dicks
- Department of Microbiology, Stellenbosch University, Stellenbosch 7600, South Africa
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12
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Hromada S, Venturelli OS. Gut microbiota interspecies interactions shape the response of Clostridioides difficile to clinically relevant antibiotics. PLoS Biol 2023; 21:e3002100. [PMID: 37167201 PMCID: PMC10174544 DOI: 10.1371/journal.pbio.3002100] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 03/30/2023] [Indexed: 05/13/2023] Open
Abstract
In the human gut, the growth of the pathogen Clostridioides difficile is impacted by a complex web of interspecies interactions with members of human gut microbiota. We investigate the contribution of interspecies interactions on the antibiotic response of C. difficile to clinically relevant antibiotics using bottom-up assembly of human gut communities. We identify 2 classes of microbial interactions that alter C. difficile's antibiotic susceptibility: interactions resulting in increased ability of C. difficile to grow at high antibiotic concentrations (rare) and interactions resulting in C. difficile growth enhancement at low antibiotic concentrations (common). Based on genome-wide transcriptional profiling data, we demonstrate that metal sequestration due to hydrogen sulfide production by the prevalent gut species Desulfovibrio piger increases the minimum inhibitory concentration (MIC) of metronidazole for C. difficile. Competition with species that display higher sensitivity to the antibiotic than C. difficile leads to enhanced growth of C. difficile at low antibiotic concentrations due to competitive release. A dynamic computational model identifies the ecological principles driving this effect. Our results provide a deeper understanding of ecological and molecular principles shaping C. difficile's response to antibiotics, which could inform therapeutic interventions.
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Affiliation(s)
- Susan Hromada
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Ophelia S. Venturelli
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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13
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Schwanbeck J, Oehmig I, Groß U, Bohne W. Clostridioides difficile minimal nutrient requirements for flagellar motility. Front Microbiol 2023; 14:1172707. [PMID: 37065145 PMCID: PMC10098170 DOI: 10.3389/fmicb.2023.1172707] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 03/15/2023] [Indexed: 04/18/2023] Open
Abstract
As many gastro-intestinal pathogens, the majority of Clostridioides difficile strains express flagella together with a complete chemotaxis system. The resulting swimming motility is likely contributing to the colonization success of this important pathogen. In contrast to the well investigated general energy metabolism of C. difficile, little is known about the metabolic requirements for maintaining the ion motive force across the membrane, which in turn powers the flagellar motor. We studied here systematically the effect of various amino acids and carbohydrates on the swimming velocity of C. difficile using video microscopy in conjunction with a software based quantification of the swimming speed. Removal of individual amino acids from the medium identified proline and cysteine as the most important amino acids that power swimming motility. Glycine, which is as proline one of the few amino acids that are reduced in Stickland reactions, was not critical for swimming motility. This suggests that the ion motive force that powers the flagellar motor, is critically depending on proline reduction. A maximal and stable swimming motility was achieved with only four compounds, including the amino acids proline, cysteine and isoleucine together with a single, but interchangeable carbohydrate source such as glucose, succinate, mannose, ribose, pyruvate, trehalose, or ethanolamine. We expect that the identified "minimal motility medium" will be useful in future investigations on the flagellar motility and chemotactic behavior in C. difficile, particularly for the unambiguous identification of chemoattractants.
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Affiliation(s)
- Julian Schwanbeck
- Institute for Medical Microbiology and Virology, University Medical Center, Göttingen, Germany
- Biotechnology Institute, University of Minnesota, Saint Paul, MN, United States
| | - Ines Oehmig
- Institute for Medical Microbiology and Virology, University Medical Center, Göttingen, Germany
| | - Uwe Groß
- Institute for Medical Microbiology and Virology, University Medical Center, Göttingen, Germany
- Uwe Groß,
| | - Wolfgang Bohne
- Institute for Medical Microbiology and Virology, University Medical Center, Göttingen, Germany
- *Correspondence: Wolfgang Bohne,
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14
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Transcriptomic Response of the Diazotrophic Bacteria Gluconacetobacter diazotrophicus Strain PAL5 to Iron Limitation and Characterization of the fur Regulatory Network. Int J Mol Sci 2022; 23:ijms23158533. [PMID: 35955667 PMCID: PMC9368920 DOI: 10.3390/ijms23158533] [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: 06/17/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 01/25/2023] Open
Abstract
Gluconacetobacter diazotrophicus has been the focus of several studies aiming to understand the mechanisms behind this endophytic diazotrophic bacterium. The present study is the first global analysis of the early transcriptional response of exponentially growing G. diazotrophicus to iron, an essential cofactor for many enzymes involved in various metabolic pathways. RNA-seq, targeted gene mutagenesis and computational motif discovery tools were used to define the G. diazotrophicusfur regulon. The data analysis showed that genes encoding functions related to iron homeostasis were significantly upregulated in response to iron limitations. Certain genes involved in secondary metabolism were overexpressed under iron-limited conditions. In contrast, it was observed that the expression of genes involved in Fe-S cluster biosynthesis, flagellar biosynthesis and type IV secretion systems were downregulated in an iron-depleted culture medium. Our results support a model that controls transcription in G. diazotrophicus by fur function. The G. diazotrophicusfur protein was able to complement an E. colifur mutant. These results provide new insights into the effects of iron on the metabolism of G. diazotrophicus, as well as demonstrate the essentiality of this micronutrient for the main characteristics of plant growth promotion by G. diazotrophicus.
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15
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Loureiro AV, Barbosa MLL, Morais MLGS, Souza IP, Terceiro LS, Martins CS, Sousa APR, Leitão RFC, Shin JH, Warren CA, Costa DVS, Brito GAC. Host and Clostridioides difficile-Response Modulated by Micronutrients and Glutamine: An Overview. Front Nutr 2022; 9:849301. [PMID: 35795588 PMCID: PMC9251358 DOI: 10.3389/fnut.2022.849301] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 05/16/2022] [Indexed: 11/17/2022] Open
Abstract
Changes in intestinal microbiota are integral to development of Clostridioides difficile (C. difficile)—associated nosocomial diarrhea. Certain diets, especially Western diets, increase susceptibility to C. difficile infection (CDI). Here, we discuss recent findings regarding how nutrients modulate response of the host and C. difficile during infection. Calcium has a role in the sporulation and germination process. Selenium is effective in reducing the total amount of C. difficile toxin A (TcdA) and toxin B (TcdB) and in decreasing its cytotoxicity. In addition, selenium phosphate synthetase deficiency reduces C. difficile growth and spore production. On the other hand, iron has a dual role in C. difficile growth. For instance, high intracellular levels can generate reactive hydroxyl radicals, whereas low levels can reduce its growth. In humans, zinc deficiency appears to be related to the recurrence of CDI, in contrast, in the CDI model in mice a diet rich in zinc increased the toxin's activity. Low vitamin D levels contribute to C. difficile colonization, toxin production, and inflammation. Furthermore, glutamine appears to protect intestinal epithelial cells from the deleterious effects of TcdA and TcdB. In conclusion, nutrients play an important role in modulating host and pathogen response. However, further studies are needed to better understand the mechanisms and address some controversies.
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Affiliation(s)
- Andréa V. Loureiro
- Department of Medical Sciences, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Maria L. L. Barbosa
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Maria L. G. S. Morais
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Ismael P. Souza
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Letícia S. Terceiro
- Department of Medical Sciences, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Conceição S. Martins
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Arkila P. R. Sousa
- Department of Pharmacology and Physiology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Renata F. C. Leitão
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Jae H. Shin
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, VA, United States
| | - Cirle A. Warren
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, VA, United States
| | - Deiziane V. S. Costa
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, VA, United States
| | - Gerly A. C. Brito
- Department of Medical Sciences, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
- Department of Morphology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
- Department of Pharmacology and Physiology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
- *Correspondence: Gerly A. C. Brito
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16
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Biwer P, Neumann-Schaal M, Henke P, Jahn D, Schulz S. Thiol Metabolism and Volatile Metabolome of Clostridioides difficile. Front Microbiol 2022; 13:864587. [PMID: 35783419 PMCID: PMC9243749 DOI: 10.3389/fmicb.2022.864587] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/22/2022] [Indexed: 11/21/2022] Open
Abstract
Clostridioides difficile (previously Clostridium difficile) causes life-threatening gut infections. The central metabolism of the bacterium is strongly influencing toxin production and consequently the infection progress. In this context, the composition and potential origin of the volatile metabolome was investigated, showing a large number of sulfur-containing volatile metabolites. Gas chromatography/mass spectrometry (GC/MS)-based headspace analyses of growing C. difficile 630Δerm cultures identified 105 mainly sulfur-containing compounds responsible of the typical C. difficile odor. Major components were identified to be 2-methyl-1-propanol, 2-methyl-1-propanethiol, 2-methyl-1-butanethiol, 4-methyl-1-pentanethiol, and as well as their disulfides. Structurally identified were 64 sulfur containing volatiles. In order to determine their biosynthetic origin, the concentrations of the sulfur-containing amino acids methionine and cysteine were varied in the growth medium. The changes observed in the volatile metabolome profile indicated that cysteine plays an essential role in the formation of the sulfur-containing volatiles. We propose that disulfides are derived from cysteine via formation of cystathionine analogs, which lead to corresponding thiols. These thiols may then be oxidized to disulfides. Moreover, methionine may contribute to the formation of short-chain disulfides through integration of methanethiol into the disulfide biosynthesis. In summary, the causative agents of the typical C. difficile odor were identified and first hypotheses for their biosynthesis were proposed.
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Affiliation(s)
- Peter Biwer
- Institute of Organic Chemistry, Technische Universität Braunschweig, Braunschweig, Germany
| | - Meina Neumann-Schaal
- Department of Metabolomics, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
- Braunschweig Integrated Centre of Systems Biology, BRICS, Braunschweig, Germany
| | - Petra Henke
- Department of Metabolomics, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology, BRICS, Braunschweig, Germany
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Braunschweig, Germany
- *Correspondence: Stefan Schulz,
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17
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Michel AM, Borrero-de Acuña JM, Molinari G, Ünal CM, Will S, Derksen E, Barthels S, Bartram W, Schrader M, Rohde M, Zhang H, Hoffmann T, Neumann-Schaal M, Bremer E, Jahn D. Cellular adaptation of Clostridioides difficile to high salinity encompasses a compatible solute-responsive change in cell morphology. Environ Microbiol 2022; 24:1499-1517. [PMID: 35106888 DOI: 10.1111/1462-2920.15925] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/27/2022]
Abstract
Infections by the pathogenic gut bacterium Clostridioides difficile cause severe diarrheas up to a toxic megacolon and are currently among the major causes of lethal bacterial infections. Successful bacterial propagation in the gut is strongly associated with the adaptation to changing nutrition-caused environmental conditions; e.g. environmental salt stresses. Concentrations of 350 mM NaCl, the prevailing salinity in the colon, led to significantly reduced growth of C. difficile. Metabolomics of salt- stressed bacteria revealed a major reduction of the central energy generation pathways, including the Stickland-fermentation reactions. No obvious synthesis of compatible solutes was observed up to 24 h of growth. The ensuing limited tolerance to high salinity and absence of compatible solute synthesis might result from an evolutionary adaptation to the exclusive life of C. difficile in the mammalian gut. Addition of the compatible solutes carnitine, glycine-betaine, γ-butyrobetaine, crotonobetaine, homobetaine, proline-betaine and dimethylsulfoniopropionate (DMSP) restored growth (choline and proline failed) under conditions of high salinity. A bioinformatically-identified OpuF-type ABC-transporter imported most of the used compatible solutes. A long-term adaptation after 48 h included a shift of the Stickland fermentation-based energy metabolism from the utilization to the accumulation of L-proline and resulted in restored growth. Surprisingly, salt stress resulted in the formation of coccoid C. difficile cells instead of the typical rod-shaped cells, a process reverted by the addition of several compatible solutes. Hence, compatible solute import via OpuF is the major immediate adaptation strategy of C. difficile to high salinity-incurred cellular stress. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Annika-Marisa Michel
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - José Manuel Borrero-de Acuña
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Universidad de Sevilla, Facultad de Biología, Departamento de Microbiología, Av. de la Reina Mercedes, n° 6, CP, 41012, Sevilla, Spain
| | - Gabriella Molinari
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Can Murat Ünal
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Sabine Will
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Elisabeth Derksen
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Stefan Barthels
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Wiebke Bartram
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Michel Schrader
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Hao Zhang
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,School of Life Science and Technology, Changchun University of Science and Technology, No. 7186 Weixing Road, 130022, Changchun, China
| | - Tamara Hoffmann
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Meina Neumann-Schaal
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Erhard Bremer
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Dieter Jahn
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
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18
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Kint N, Morvan C, Martin-Verstraete I. Oxygen response and tolerance mechanisms in Clostridioides difficile. Curr Opin Microbiol 2021; 65:175-182. [PMID: 34896836 DOI: 10.1016/j.mib.2021.11.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 11/08/2021] [Accepted: 11/17/2021] [Indexed: 01/11/2023]
Abstract
While the gut is typically thought of as anoxic, there are two intersecting and decreasing oxygen gradients that are observed in the gut: oxygen decreases from the small to the large intestine and from the intestinal epithelium toward the colon lumen. Gut oxygen levels also increase following antibiotic induced-dysbiosis. While dysbiosis favors growth of Clostridioides difficile, the oxygen increase also causes stress to this anaerobic enteropathogen. To circumvent oxygen threat, C. difficile has developed efficient strategies: sporulation, biofilm formation, the rerouting of central metabolism and the production of oxygen detoxification enzymes. Especially, reverse rubrerythrins and flavodiiron proteins involved in oxygen reduction are crucial in C. difficile ability to tolerate and survive the oxygen concentrations encountered in the gastrointestinal tract. Two regulators, σB and PerR, play pivotal role in the mastering of these adaptive responses by controlling the various systems that protect cells from oxidative damages.
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Affiliation(s)
- Nicolas Kint
- Institut Pasteur, Université de Paris, UMR CNRS 2001, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Claire Morvan
- Institut Pasteur, Université de Paris, UMR CNRS 2001, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Isabelle Martin-Verstraete
- Institut Pasteur, Université de Paris, UMR CNRS 2001, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France; Institut Universitaire de France, France.
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19
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Weiss A, Lopez CA, Beavers WN, Rodriguez J, Skaar EP. Clostridioides difficile strain-dependent and strain-independent adaptations to a microaerobic environment. Microb Genom 2021; 7:000738. [PMID: 34908523 PMCID: PMC8767335 DOI: 10.1099/mgen.0.000738] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 11/02/2021] [Indexed: 12/18/2022] Open
Abstract
Clostridioides difficile (formerly Clostridium difficile) colonizes the gastrointestinal tract following disruption of the microbiota and can initiate a spectrum of clinical manifestations ranging from asymptomatic to life-threatening colitis. Following antibiotic treatment, luminal oxygen concentrations increase, exposing gut microbes to potentially toxic reactive oxygen species. Though typically regarded as a strict anaerobe, C. difficile can grow at low oxygen concentrations. How this bacterium adapts to a microaerobic environment and whether those responses to oxygen are conserved amongst strains is not entirely understood. Here, two C. difficile strains (630 and CD196) were cultured in 1.5% oxygen and the transcriptional response to long-term oxygen exposure was evaluated via RNA-sequencing. During growth in a microaerobic environment, several genes predicted to protect against oxidative stress were upregulated, including those for rubrerythrins and rubredoxins. Transcription of genes involved in metal homeostasis was also positively correlated with increased oxygen levels and these genes were amongst the most differentially transcribed. To directly compare the transcriptional landscape between C. difficile strains, a 'consensus-genome' was generated. On the basis of the identified conserved genes, basal transcriptional differences as well as variations in the response to oxygen were evaluated. While several responses were similar between the strains, there were significant differences in the abundance of transcripts involved in amino acid and carbohydrate metabolism. Furthermore, intracellular metal concentrations significantly varied both in an oxygen-dependent and oxygen-independent manner. Overall, these results indicate that C. difficile adapts to grow in a low oxygen environment through transcriptional changes, though the specific strategy employed varies between strains.
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Affiliation(s)
- Andy Weiss
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christopher A. Lopez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biological Sciences, California State University Sacramento, Sacramento, CA, USA
| | - William N. Beavers
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jhoana Rodriguez
- Department of Biological Sciences, California State University Sacramento, Sacramento, CA, USA
| | - Eric P. Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
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20
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Gomez SY, Patel J, Lopez CA. What's metal got to do with it? Transition metals in Clostridioides difficile infection. Curr Opin Microbiol 2021; 65:116-122. [PMID: 34839238 DOI: 10.1016/j.mib.2021.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/27/2022]
Abstract
The enteric pathogen Clostridioides difficile overcomes barriers to colonization imposed by the microbiota and host immune response to induce disease. To navigate the dynamic gut environment, C. difficile must respond to dietary and host-mediated fluctuations in transition metal availability. Transition metals are required trace nutrients that foster inter-microbial competition when limited, inhibit bacterial growth through host sequestration, or induce toxicity in excess. This review highlights recent evidence that transition metals influence multiple stages of C. difficile colonization and that C. difficile initiates a coordinated response to maintain metal-dependent homeostasis. Further exploration of the mechanisms of C. difficile metal sensing and nutrient competition with the microbiota will be necessary for the therapeutic manipulation of the gut environment during C. difficile infection.
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Affiliation(s)
- Suzanna Y Gomez
- Department of Biological Sciences, California State University Sacramento, Sacramento, CA, United States
| | - Jay Patel
- Department of Biological Sciences, California State University Sacramento, Sacramento, CA, United States
| | - Christopher A Lopez
- Department of Biological Sciences, California State University Sacramento, Sacramento, CA, United States.
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21
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Girinathan BP, DiBenedetto N, Worley JN, Peltier J, Arrieta-Ortiz ML, Immanuel SRC, Lavin R, Delaney ML, Cummins CK, Hoffman M, Luo Y, Gonzalez-Escalona N, Allard M, Onderdonk AB, Gerber GK, Sonenshein AL, Baliga NS, Dupuy B, Bry L. In vivo commensal control of Clostridioides difficile virulence. Cell Host Microbe 2021; 29:1693-1708.e7. [PMID: 34637781 DOI: 10.1016/j.chom.2021.09.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/26/2021] [Accepted: 09/16/2021] [Indexed: 12/23/2022]
Abstract
Leveraging systems biology approaches, we illustrate how metabolically distinct species of Clostridia protect against or worsen Clostridioides difficile infection in mice by modulating the pathogen's colonization, growth, and virulence to impact host survival. Gnotobiotic mice colonized with the amino acid fermenter Paraclostridium bifermentans survive infection with reduced disease severity, while mice colonized with the butyrate-producer, Clostridium sardiniense, succumb more rapidly. Systematic in vivo analyses revealed how each commensal alters the gut-nutrient environment to modulate the pathogen's metabolism, gene regulatory networks, and toxin production. Oral administration of P. bifermentans rescues conventional, clindamycin-treated mice from lethal C. difficile infection in a manner similar to that of monocolonized animals, thereby supporting the therapeutic potential of this commensal species. Our findings lay the foundation for mechanistically informed therapies to counter C. difficile disease using systems biology approaches to define host-commensal-pathogen interactions in vivo.
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Affiliation(s)
- Brintha P Girinathan
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Nicholas DiBenedetto
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jay N Worley
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; National Center of Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Johann Peltier
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, UMR CNRS 2001, Université de Paris, 25-28 Rue du Dr. Roux, Institut Pasteur, 75015 Paris Cedex, France; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198, Gif-sur-yvette Cedex, France
| | | | | | - Richard Lavin
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mary L Delaney
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Clinical Microbiology Laboratory, Department of Pathology, Brigham & Women's Hospital, Boston, MA 02115, USA
| | - Christopher K Cummins
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Maria Hoffman
- Center for Food Safety and Applied Nutrition, United States Food and Drug Administration, Department of Microbiology, College Park, MD 20740, USA
| | - Yan Luo
- Center for Food Safety and Applied Nutrition, United States Food and Drug Administration, Department of Microbiology, College Park, MD 20740, USA
| | - Narjol Gonzalez-Escalona
- Center for Food Safety and Applied Nutrition, United States Food and Drug Administration, Department of Microbiology, College Park, MD 20740, USA
| | - Marc Allard
- Center for Food Safety and Applied Nutrition, United States Food and Drug Administration, Department of Microbiology, College Park, MD 20740, USA
| | - Andrew B Onderdonk
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Clinical Microbiology Laboratory, Department of Pathology, Brigham & Women's Hospital, Boston, MA 02115, USA
| | - Georg K Gerber
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard-MIT Health Sciences & Technology, Cambridge, MA 02139, USA
| | - Abraham L Sonenshein
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA
| | | | - Bruno Dupuy
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, UMR CNRS 2001, Université de Paris, 25-28 Rue du Dr. Roux, Institut Pasteur, 75015 Paris Cedex, France
| | - Lynn Bry
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Clinical Microbiology Laboratory, Department of Pathology, Brigham & Women's Hospital, Boston, MA 02115, USA.
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22
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Arrieta-Ortiz ML, Immanuel SRC, Turkarslan S, Wu WJ, Girinathan BP, Worley JN, DiBenedetto N, Soutourina O, Peltier J, Dupuy B, Bry L, Baliga NS. Predictive regulatory and metabolic network models for systems analysis of Clostridioides difficile. Cell Host Microbe 2021; 29:1709-1723.e5. [PMID: 34637780 PMCID: PMC8595754 DOI: 10.1016/j.chom.2021.09.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/29/2021] [Accepted: 09/16/2021] [Indexed: 12/15/2022]
Abstract
We present predictive models for comprehensive systems analysis of Clostridioides difficile, the etiology of pseudomembranous colitis. By leveraging 151 published transcriptomes, we generated an EGRIN model that organizes 90% of C. difficile genes into a transcriptional regulatory network of 297 co-regulated modules, implicating genes in sporulation, carbohydrate transport, and metabolism. By advancing a metabolic model through addition and curation of metabolic reactions including nutrient uptake, we discovered 14 amino acids, diverse carbohydrates, and 10 metabolic genes as essential for C. difficile growth in the intestinal environment. Finally, we developed a PRIME model to uncover how EGRIN-inferred combinatorial gene regulation by transcription factors, such as CcpA and CodY, modulates essential metabolic processes to enable C. difficile growth relative to commensal colonization. The C. difficile interactive web portal provides access to these model resources to support collaborative systems-level studies of context-specific virulence mechanisms in C. difficile.
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Affiliation(s)
| | | | | | - Wei-Ju Wu
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Brintha P Girinathan
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jay N Worley
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Nicholas DiBenedetto
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Olga Soutourina
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-yvette 91198, France
| | - Johann Peltier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-yvette 91198, France
| | - Bruno Dupuy
- Laboratoire Pathogenèse des Bactéries anaérobies, Institut Pasteur, Université de Paris, UMR CNRS 2001, Paris 75015, France
| | - Lynn Bry
- Massachusetts Host-Microbiome Center, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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23
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Morvan C, Folgosa F, Kint N, Teixeira M, Martin-Verstraete I. Responses of Clostridia to oxygen: from detoxification to adaptive strategies. Environ Microbiol 2021; 23:4112-4125. [PMID: 34245087 DOI: 10.1111/1462-2920.15665] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 07/02/2021] [Accepted: 07/07/2021] [Indexed: 11/30/2022]
Abstract
Clostridia comprise bacteria of environmental, biotechnological and medical interest and many commensals of the gut microbiota. Because of their strictly anaerobic lifestyle, oxygen is a major stress for Clostridia. However, recent data showed that these bacteria can cope with O2 better than expected for obligate anaerobes through their ability to scavenge, detoxify and consume O2 . Upon O2 exposure, Clostridia redirect their central metabolism onto pathways less O2 -sensitive and induce the expression of genes encoding enzymes involved in O2 -reduction and in the repair of oxidized damaged molecules. While Faecalibacterium prausnitzii efficiently consumes O2 through a specific extracellular electron shuttling system requiring riboflavin, enzymes such as rubrerythrins and flavodiiron proteins with NAD(P)H-dependent O2 - and/or H2 O2 -reductase activities are usually encoded in other Clostridia. These two classes of enzymes play indeed a pivotal role in O2 tolerance in Clostridioides difficile and Clostridium acetobutylicum. Two main signalling pathways triggering O2 -induced responses have been described so far in Clostridia. PerR acts as a key regulator of the O2 - and/or reactive oxygen species-defence machinery while in C. difficile, σB , the sigma factor of the general stress response also plays a crucial role in O2 tolerance by controlling the expression of genes involved in O2 scavenging and repair systems.
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Affiliation(s)
- Claire Morvan
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, F-75015, France
| | - Filipe Folgosa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Nicolas Kint
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, F-75015, France
| | - Miguel Teixeira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Isabelle Martin-Verstraete
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, F-75015, France
- Institut Universitaire de France, Paris, France
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24
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Knight DR, Imwattana K, Kullin B, Guerrero-Araya E, Paredes-Sabja D, Didelot X, Dingle KE, Eyre DW, Rodríguez C, Riley TV. Major genetic discontinuity and novel toxigenic species in Clostridioides difficile taxonomy. eLife 2021; 10:64325. [PMID: 34114561 PMCID: PMC8241443 DOI: 10.7554/elife.64325] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 06/08/2021] [Indexed: 12/17/2022] Open
Abstract
Clostridioides difficile infection (CDI) remains an urgent global One Health threat. The genetic heterogeneity seen across C. difficile underscores its wide ecological versatility and has driven the significant changes in CDI epidemiology seen in the last 20 years. We analysed an international collection of over 12,000 C. difficile genomes spanning the eight currently defined phylogenetic clades. Through whole-genome average nucleotide identity, and pangenomic and Bayesian analyses, we identified major taxonomic incoherence with clear species boundaries for each of the recently described cryptic clades CI–III. The emergence of these three novel genomospecies predates clades C1–5 by millions of years, rewriting the global population structure of C. difficile specifically and taxonomy of the Peptostreptococcaceae in general. These genomospecies all show unique and highly divergent toxin gene architecture, advancing our understanding of the evolution of C. difficile and close relatives. Beyond the taxonomic ramifications, this work may impact the diagnosis of CDI.
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Affiliation(s)
- Daniel R Knight
- Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, Australia.,School of Biomedical Sciences, the University of Western Australia, Nedlands, Australia
| | - Korakrit Imwattana
- School of Biomedical Sciences, the University of Western Australia, Nedlands, Australia.,Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Brian Kullin
- Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Enzo Guerrero-Araya
- Microbiota-Host Interactions and Clostridia Research Group, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile.,Millenium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - Daniel Paredes-Sabja
- Microbiota-Host Interactions and Clostridia Research Group, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile.,Millenium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile.,Department of Biology, Texas A&M University, College Station, United States
| | - Xavier Didelot
- School of Life Sciences and Department of Statistics, University of Warwick, Coventry, United Kingdom
| | - Kate E Dingle
- Nuffield Department of Clinical Medicine, University of Oxford, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - David W Eyre
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - César Rodríguez
- Facultad de Microbiología & Centro de Investigación en Enfermedades Tropicales (CIET), Universidad de Costa Rica, San José, Costa Rica
| | - Thomas V Riley
- Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, Australia.,School of Biomedical Sciences, the University of Western Australia, Nedlands, Australia.,Department of Microbiology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Australia.,School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
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25
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Brauer M, Lassek C, Hinze C, Hoyer J, Becher D, Jahn D, Sievers S, Riedel K. What's a Biofilm?-How the Choice of the Biofilm Model Impacts the Protein Inventory of Clostridioides difficile. Front Microbiol 2021; 12:682111. [PMID: 34177868 PMCID: PMC8225356 DOI: 10.3389/fmicb.2021.682111] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/12/2021] [Indexed: 12/18/2022] Open
Abstract
The anaerobic pathogen Clostridioides difficile is perfectly equipped to survive and persist inside the mammalian intestine. When facing unfavorable conditions C. difficile is able to form highly resistant endospores. Likewise, biofilms are currently discussed as form of persistence. Here a comprehensive proteomics approach was applied to investigate the molecular processes of C. difficile strain 630Δerm underlying biofilm formation. The comparison of the proteome from two different forms of biofilm-like growth, namely aggregate biofilms and colonies on agar plates, revealed major differences in the formation of cell surface proteins, as well as enzymes of its energy and stress metabolism. For instance, while the obtained data suggest that aggregate biofilm cells express both flagella, type IV pili and enzymes required for biosynthesis of cell-surface polysaccharides, the S-layer protein SlpA and most cell wall proteins (CWPs) encoded adjacent to SlpA were detected in significantly lower amounts in aggregate biofilm cells than in colony biofilms. Moreover, the obtained data suggested that aggregate biofilm cells are rather actively growing cells while colony biofilm cells most likely severely suffer from a lack of reductive equivalents what requires induction of the Wood-Ljungdahl pathway and C. difficile’s V-type ATPase to maintain cell homeostasis. In agreement with this, aggregate biofilm cells, in contrast to colony biofilm cells, neither induced toxin nor spore production. Finally, the data revealed that the sigma factor SigL/RpoN and its dependent regulators are noticeably induced in aggregate biofilms suggesting an important role of SigL/RpoN in aggregate biofilm formation.
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Affiliation(s)
- Madita Brauer
- Department for Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Christian Lassek
- Department for Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Christian Hinze
- Department for Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Juliane Hoyer
- Department for Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Dörte Becher
- Department for Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology (BRICS), Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Susanne Sievers
- Department for Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Katharina Riedel
- Department for Microbial Physiology and Molecular Biology, Institute of Microbiology, University of Greifswald, Greifswald, Germany
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26
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Pipatthana M, Harnvoravongchai P, Pongchaikul P, Likhitrattanapisal S, Phanchana M, Chankhamhaengdecha S, Janvilisri T. The repertoire of ABC proteins in Clostridioides difficile. Comput Struct Biotechnol J 2021; 19:2905-2920. [PMID: 34094001 PMCID: PMC8144104 DOI: 10.1016/j.csbj.2021.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 05/02/2021] [Accepted: 05/05/2021] [Indexed: 11/07/2022] Open
Abstract
ABC transporters transport substrates across membranes driven by ATP hydrolysis. ABC proteins of C. difficile 630 can be classified into 12 sub-families. Most NPs are found within sub-families involving in drug export. Most core NPs in C. difficile are associated with drug efflux system. ABC proteins in sub-families 3, 6, 7, and 9 may participate in drug resistance.
ATP-binding cassette (ABC) transporters belong to one of the largest membrane protein superfamilies, which function in translocating substrates across biological membranes using energy from ATP hydrolysis. Currently, the classification of ABC transporters in Clostridioides difficile is not complete. Therefore, the sequence-function relationship of all ABC proteins encoded within the C. difficile genome was analyzed. Identification of protein domains associated with the ABC system in the C. difficile 630 reference genome revealed 226 domains: 97 nucleotide-binding domains (NBDs), 98 transmembrane domains (TMDs), 30 substrate-binding domains (SBDs), and one domain with features of an adaptor protein. Gene organization and transcriptional unit analyses indicated the presence of 78 ABC systems comprising 28 importers and 50 exporters. Based on NBD sequence similarity, ABC transporters were classified into 12 sub-families according to their substrates. Interestingly, all ABC exporters, accounting for 64% of the total ABC systems, are involved in antibiotic resistance. Based on analysis of ABC proteins from 49 C. difficile strains, the majority of core NBDs are predicted to be involved in multidrug resistance systems, consistent with the ability of this organism to survive exposure to an array of antibiotics. Our findings herein provide another step toward a better understanding of the function and evolutionary relationships of ABC proteins in this pathogen.
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Affiliation(s)
- Methinee Pipatthana
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | | | - Pisut Pongchaikul
- Chakri Naruebodindra Medical Institute, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Samut Prakarn, Thailand
| | - Somsak Likhitrattanapisal
- Thailand Bioresource Research Center (TBRC), National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, Thailand
| | - Matthew Phanchana
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Tavan Janvilisri
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
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27
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Bradley JM, Svistunenko DA, Wilson MT, Hemmings AM, Moore GR, Le Brun NE. Bacterial iron detoxification at the molecular level. J Biol Chem 2021; 295:17602-17623. [PMID: 33454001 PMCID: PMC7762939 DOI: 10.1074/jbc.rev120.007746] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/07/2020] [Indexed: 01/18/2023] Open
Abstract
Iron is an essential micronutrient, and, in the case of bacteria, its availability is commonly a growth-limiting factor. However, correct functioning of cells requires that the labile pool of chelatable "free" iron be tightly regulated. Correct metalation of proteins requiring iron as a cofactor demands that such a readily accessible source of iron exist, but overaccumulation results in an oxidative burden that, if unchecked, would lead to cell death. The toxicity of iron stems from its potential to catalyze formation of reactive oxygen species that, in addition to causing damage to biological molecules, can also lead to the formation of reactive nitrogen species. To avoid iron-mediated oxidative stress, bacteria utilize iron-dependent global regulators to sense the iron status of the cell and regulate the expression of proteins involved in the acquisition, storage, and efflux of iron accordingly. Here, we survey the current understanding of the structure and mechanism of the important members of each of these classes of protein. Diversity in the details of iron homeostasis mechanisms reflect the differing nutritional stresses resulting from the wide variety of ecological niches that bacteria inhabit. However, in this review, we seek to highlight the similarities of iron homeostasis between different bacteria, while acknowledging important variations. In this way, we hope to illustrate how bacteria have evolved common approaches to overcome the dual problems of the insolubility and potential toxicity of iron.
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Affiliation(s)
- Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom.
| | | | - Michael T Wilson
- School of Life Sciences, University of Essex, Colchester, United Kingdom
| | - Andrew M Hemmings
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom; Centre for Molecular and Structural Biochemistry, School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Geoffrey R Moore
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Nick E Le Brun
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom.
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28
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Kundra P, Rachmühl C, Lacroix C, Geirnaert A. Role of Dietary Micronutrients on Gut Microbial Dysbiosis and Modulation in Inflammatory Bowel Disease. Mol Nutr Food Res 2021. [DOI: 10.1002/mnfr.201901271] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Palni Kundra
- Laboratory of Food Biotechnology Institute of Food Nutrition and Health Schmelzbergstrasse 7 Zürich 8092 Switzerland
| | - Carole Rachmühl
- Laboratory of Food Biotechnology Institute of Food Nutrition and Health Schmelzbergstrasse 7 Zürich 8092 Switzerland
| | - Christophe Lacroix
- Laboratory of Food Biotechnology Institute of Food Nutrition and Health Schmelzbergstrasse 7 Zürich 8092 Switzerland
| | - Annelies Geirnaert
- Laboratory of Food Biotechnology Institute of Food Nutrition and Health Schmelzbergstrasse 7 Zürich 8092 Switzerland
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29
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Hofmann JD, Biedendieck R, Michel AM, Schomburg D, Jahn D, Neumann-Schaal M. Influence of L-lactate and low glucose concentrations on the metabolism and the toxin formation of Clostridioides difficile. PLoS One 2021; 16:e0244988. [PMID: 33411772 PMCID: PMC7790285 DOI: 10.1371/journal.pone.0244988] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 12/18/2020] [Indexed: 12/14/2022] Open
Abstract
The virulence of Clostridioides difficile (formerly Clostridium difficile) is mainly caused by its two toxins A and B. Their formation is significantly regulated by metabolic processes. Here we investigated the influence of various sugars (glucose, fructose, mannose, trehalose), sugar derivatives (mannitol and xylitol) and L-lactate on toxin synthesis. Fructose, mannose, trehalose, mannitol and xylitol in the growth medium resulted in an up to 2.2-fold increase of secreted toxin. Low glucose concentration of 2 g/L increased the toxin concentration 1.4-fold compared to growth without glucose, while high glucose concentrations in the growth medium (5 and 10 g/L) led to up to 6.6-fold decrease in toxin formation. Transcriptomic and metabolic investigation of the low glucose effect pointed towards an inactive CcpA and Rex regulatory system. L-lactate (500 mg/L) significantly reduced extracellular toxin formation. Transcriptome analyses of the later process revealed the induction of the lactose utilization operon encoding lactate racemase (larA), electron confurcating lactate dehydrogenase (CDIF630erm_01321) and the corresponding electron transfer flavoprotein (etfAB). Metabolome analyses revealed L-lactate consumption and the formation of pyruvate. The involved electron confurcation process might be responsible for the also observed reduction of the NAD+/NADH ratio which in turn is apparently linked to reduced toxin release from the cell.
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Affiliation(s)
- Julia Danielle Hofmann
- Department of Bioinformatics and Biochemistry, Technische Universität Braunschweig, Braunschweig, Germany
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
| | - Rebekka Biedendieck
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Annika-Marisa Michel
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Dietmar Schomburg
- Department of Bioinformatics and Biochemistry, Technische Universität Braunschweig, Braunschweig, Germany
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Meina Neumann-Schaal
- Department of Bioinformatics and Biochemistry, Technische Universität Braunschweig, Braunschweig, Germany
- Braunschweig Integrated Centre of Systems Biology (BRICS), Braunschweig, Germany
- Leibniz Institute DSMZ—German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
- * E-mail:
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30
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Sousa Gerós A, Simmons A, Drakesmith H, Aulicino A, Frost JN. The battle for iron in enteric infections. Immunology 2020; 161:186-199. [PMID: 32639029 PMCID: PMC7576875 DOI: 10.1111/imm.13236] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/01/2020] [Indexed: 02/06/2023] Open
Abstract
Iron is an essential element for almost all living organisms, but can be extremely toxic in high concentrations. All organisms must therefore employ homeostatic mechanisms to finely regulate iron uptake, usage and storage in the face of dynamic environmental conditions. The critical step in mammalian systemic iron homeostasis is the fine regulation of dietary iron absorption. However, as the gastrointestinal system is also home to >1014 bacteria, all of which engage in their own programmes of iron homeostasis, the gut represents an anatomical location where the inter-kingdom fight for iron is never-ending. Here, we explore the molecular mechanisms of, and interactions between, host and bacterial iron homeostasis in the gastrointestinal tract. We first detail how mammalian systemic and cellular iron homeostasis influences gastrointestinal iron availability. We then focus on two important human pathogens, Salmonella and Clostridia; despite their differences, they exemplify how a bacterial pathogen must navigate and exploit this web of iron homeostasis interactions to avoid host nutritional immunity and replicate successfully. We then reciprocally explore how iron availability interacts with the gastrointestinal microbiota, and the consequences of this on mammalian physiology and pathogen iron acquisition. Finally, we address how understanding the battle for iron in the gastrointestinal tract might inform clinical practice and inspire new treatments for important diseases.
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Affiliation(s)
- Ana Sousa Gerós
- MRC Human Immunology UnitWeatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
- Translational Gastroenterology UnitJohn Radcliffe HospitalOxfordUK
| | - Alison Simmons
- MRC Human Immunology UnitWeatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
- Translational Gastroenterology UnitJohn Radcliffe HospitalOxfordUK
| | - Hal Drakesmith
- MRC Human Immunology UnitWeatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
| | - Anna Aulicino
- MRC Human Immunology UnitWeatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
- Translational Gastroenterology UnitJohn Radcliffe HospitalOxfordUK
| | - Joe N. Frost
- MRC Human Immunology UnitWeatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
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31
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IurV, Encoded by ORF VCA0231, Is Involved in the Regulation of Iron Uptake Genes in Vibrio cholerae. Genes (Basel) 2020; 11:genes11101184. [PMID: 33053678 PMCID: PMC7600106 DOI: 10.3390/genes11101184] [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: 09/08/2020] [Revised: 10/05/2020] [Accepted: 10/07/2020] [Indexed: 11/16/2022] Open
Abstract
The pathogen Vibrio cholerae has multiple iron acquisition systems which allow bacteria to exploit a variety of iron sources across the different environments on which it thrives. The expression of such iron uptake systems is highly regulated, mainly by the master iron homeostasis regulator Fur but also by other mechanisms. Recently, we documented that the expression of many of the iron-responsive genes is also modulated by riboflavin. Among them, the open reading frame VCA0231, repressed both by riboflavin and iron, encodes a putative transcriptional regulator of the AraC/XylS family. Nonetheless, the genes or functions affected by this factor are unknown. In the present study, a series of in silico analyses was performed in order to identify the putative functions associated with the product of VCA0231. The STRING database predicted many iron uptake genes as functional partners for the product of VCA0231. In addition, a genomic neighborhood analysis with the Enzyme Function Initiative tools detected many Pfam families involved in iron homeostasis genetically associated with VCA0231. Moreover, a phylogenetic tree showed that other AraC/XylS members known to regulate siderophore utilization in bacteria clustered together and the product of VCA0231 localized in this cluster. This suggested that the product of VCA0231, here named IurV, is involved in the regulation of iron uptake processes. RNAseq was performed to determine the transcriptional effects of a deletion in VCA0231. A total of 52 genes were overexpressed and 21 genes were downregulated in response to the iurV deletion. Among these, several iron uptake genes and other iron homeostasis-related genes were found. Six gene ontology (GO) functional terms were enriched in the upregulated genes, of which five were related to iron metabolism. The regulatory pattern observed in the transcriptomics of a subset of genes was independently confirmed by quantitative real time PCR analysis. The results indicate that IurV is a novel regulator of the AraC/XylS family involved in the repression of iron uptake genes. Whether this effect is direct or indirect remains to be determined.
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Redefining the Clostridioides difficile σ B Regulon: σ B Activates Genes Involved in Detoxifying Radicals That Can Result from the Exposure to Antimicrobials and Hydrogen Peroxide. mSphere 2020; 5:5/5/e00728-20. [PMID: 32938698 PMCID: PMC7494833 DOI: 10.1128/msphere.00728-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In many Gram-positive bacteria, the general stress response is regulated at the transcriptional level by the alternative sigma factor sigma B (σB). In C. difficile, σB has been implicated in protection against stressors such as reactive oxygen species (ROS) and antimicrobial compounds. Here, we used an anti-σB antibody to demonstrate time-limited overproduction of σB in C. difficile despite its toxicity at higher cellular concentrations. This toxicity eventually led to the loss of the plasmid used for anhydrotetracycline-induced σB gene expression. Inducible σB overproduction uncouples σB expression from its native regulatory network and allows for the refinement of the previously proposed σB regulon. At least 32% of the regulon was found to consist of genes involved in the response to reactive radicals. Direct gene activation by C. difficile σB was demonstrated through in vitro runoff transcription of specific target genes (cd0350, cd3614, cd3605, and cd2963). Finally, we demonstrated that different antimicrobials and hydrogen peroxide induce these genes in a manner dependent on this sigma factor, using a plate-based luciferase reporter assay. Together, our work suggests that lethal exposure to antimicrobials may result in the formation of toxic radicals that lead to σB-dependent gene activation.IMPORTANCE Sigma B is the alternative sigma factor governing stress response in many Gram-positive bacteria. In C. difficile, a sigB mutant shows pleiotropic transcriptional effects. Here, we determine genes that are likely direct targets of σB by evaluating the transcriptional effects of σB overproduction, provide biochemical evidence of direct transcriptional activation by σB, and show that σB-dependent genes can be activated by antimicrobials. Together, our data suggest that σB is a key player in dealing with toxic radicals.
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Lozano Aguirre LF, Salazar JC, Vásquez JI, García-Angulo VA. Interdependency of regulatory effects of iron and riboflavin in the foodborne pathogen Shigella flexneri determined by integral transcriptomics. PeerJ 2020; 8:e9553. [PMID: 32983629 PMCID: PMC7500357 DOI: 10.7717/peerj.9553] [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: 09/26/2019] [Accepted: 06/24/2020] [Indexed: 11/24/2022] Open
Abstract
Shigella flexneri is the causative agent of dysentery. For pathogens, iron is a critical micronutrient as its bioavailability is usually low in bacterial niches. This metal is involved in critical physiological processes mainly as a component of important metabolic molecules involved in redox reactions. Usually bacteria respond to fluctuations in iron availability to regulate iron acquisition and other iron-related functions. Recently the close metabolic feedback between iron and riboflavin, another pivotal biological redox agent, began to draw attention in bacteria. This is a widespread biological phenomenon, partly characterized by the coordination of regulatory responses to iron and riboflavin, probably owed to the involvement of these cofactors in common processes. Nonetheless, no systematic analyses to determine the extent of this regulatory effect have been performed in any species. Here, the transcriptomics responses to iron, riboflavin, iron in the presence of riboflavin and riboflavin in the presence of iron were assessed and compared in S. flexneri. The riboflavin regulon had a 43% overlap with the iron regulon. Notably, the presence of riboflavin highly increased the number of iron-responsive genes. Reciprocally, iron drastically changed the pool of riboflavin-responsive genes. Gene ontology (GO) functional terms enrichment analysis showed that biological processes were distinctively enriched for each subgroup of responsive genes. Among the biological processes regulated by iron and riboflavin were iron uptake, amino acids metabolism and electron transfer for ATP synthesis. Thus, iron and riboflavin highly affect the transcriptomics responses induced by each other in S. flexneri. GO terms analysis suggests that iron and riboflavin coordinately regulate specific physiological functions involving redox metabolism.
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Affiliation(s)
- Luis Fernando Lozano Aguirre
- Unidad de Análisis Bioinformáticos, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Juan Carlos Salazar
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - José Ignacio Vásquez
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John, Canada
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RirA of Dinoroseobacter shibae senses iron via a [3Fe-4S]1+ cluster co-ordinated by three cysteine residues. Biochem J 2020; 477:191-212. [PMID: 31860023 DOI: 10.1042/bcj20180734] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/15/2022]
Abstract
In the marine bacterium, Dinoroseobacter shibae the transcription factor rhizobial iron regulator A (RirA) is involved in the adaptation to iron-limited growth conditions. In vitro iron and sulfide content determinations in combination with UV/Vis and electron paramagnetic resonance (EPR) spectroscopic analyses using anaerobically purified, recombinant RirA protein suggested a [3Fe-4S]1+ cluster as a cofactor. In vivo Mössbauer spectroscopy also corroborated the presence of a [3Fe-4S]1+ cluster in RirA. Moreover, the cluster was found to be redox stable. Three out of four highly conserved cysteine residues of RirA (Cys 91, Cys 99, Cys 105) were found essential for the [3Fe-4S]1+ cluster coordination. The dimeric structure of the RirA protein was independent of the presence of the [3Fe-4S]1+ cluster. Electro mobility shift assays demonstrated the essential role of an intact [3Fe-4S]1+ cluster for promoter binding by RirA. The DNA binding site was identified by DNase I footprinting. Mutagenesis studies in combination with DNA binding assays confirmed the promoter binding site as 3'-TTAAN10AATT-5'. This work describes a novel mechanism for the direct sensing of cellular iron levels in bacteria by an iron-responsive transcriptional regulator using the integrity of a redox-inactive [3Fe-4S]1+ cluster, and further contributes to the general understanding of iron regulation in marine bacteria.
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The Impact of pH on Clostridioides difficile Sporulation and Physiology. Appl Environ Microbiol 2020; 86:AEM.02706-19. [PMID: 31811041 DOI: 10.1128/aem.02706-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 12/03/2019] [Indexed: 12/18/2022] Open
Abstract
Clostridioides difficile is a pathogenic bacterium that infects the human colon to cause diarrheal disease. Growth of the bacterium is known to be dependent on certain bile acids, oxygen levels, and nutrient availability in the intestine, but how the environmental pH can influence C. difficile is mostly unknown. Previous studies indicated that C. difficile modulates the intestinal pH, and prospective cohort studies have found a strong association between a more alkaline fecal pH and C. difficile infection. Based on these data, we hypothesized that C. difficile physiology can be affected by various pH conditions. In this study, we investigated the impact of a range of pH conditions on C. difficile to assess potential effects on growth, sporulation, motility, and toxin production in the strains 630Δerm and R20291. We observed pH-dependent differences in sporulation rate, spore morphology, and viability. Sporulation frequency was lowest under acidic conditions, and differences in cell morphology were apparent at low pH. In alkaline environments, C. difficile sporulation was greater for strain 630Δerm, whereas R20291 produced relatively high levels of spores in a broad range of pH conditions. Rapid changes in pH during exponential growth impacted sporulation similarly among the strains. Furthermore, we observed an increase in C. difficile motility with increases in pH, and strain-dependent differences in toxin production under acidic conditions. The data demonstrate that pH is an important parameter that affects C. difficile physiology and may reveal relevant insights into the growth and dissemination of this pathogen.IMPORTANCE Clostridioides difficile is an anaerobic bacterium that causes gastrointestinal disease. C. difficile forms dormant spores which can survive harsh environmental conditions, allowing their spread to new hosts. In this study, we determine how intestinally relevant pH conditions impact C. difficile physiology in the two divergent strains, 630Δerm and R20291. Our data demonstrate that low pH conditions reduce C. difficile growth, sporulation, and motility. However, toxin production and spore morphology were differentially impacted in the two strains at low pH. In addition, we observed that alkaline environments reduce C. difficile growth, but increase cell motility. When pH was adjusted rapidly during growth, we observed similar impacts on both strains. This study provides new insights into the phenotypic diversity of C. difficile grown under diverse pH conditions present in the intestinal tract, and demonstrates similarities and differences in the pH responses of different C. difficile isolates.
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Lopez CA, Beavers WN, Weiss A, Knippel RJ, Zackular JP, Chazin W, Skaar EP. The Immune Protein Calprotectin Impacts Clostridioides difficile Metabolism through Zinc Limitation. mBio 2019; 10:e02289-19. [PMID: 31744916 PMCID: PMC6867894 DOI: 10.1128/mbio.02289-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 10/09/2019] [Indexed: 02/06/2023] Open
Abstract
The intestines house a diverse microbiota that must compete for nutrients to survive, but the specific limiting nutrients that control pathogen colonization are not clearly defined. Clostridioides difficile colonization typically requires prior disruption of the microbiota, suggesting that outcompeting commensals for resources is critical to establishing C. difficile infection (CDI). The immune protein calprotectin (CP) is released into the gut lumen during CDI to chelate zinc (Zn) and other essential nutrient metals. Yet, the impact of Zn limitation on C. difficile colonization is unknown. To define C. difficile responses to Zn limitation, we performed RNA sequencing on C. difficile exposed to CP. In medium containing CP, C. difficile upregulated genes involved in metal homeostasis and amino acid metabolism. To identify CP-responsive genes important during infection, we measured the abundance of select C. difficile transcripts in a mouse CDI model relative to expression in vitro Gene transcripts involved in selenium (Se)-dependent proline fermentation increased during infection and in response to CP. Increased proline fermentation gene transcription was dependent on CP Zn binding and proline availability, yet proline fermentation was only enhanced when Se was supplemented. CP-deficient mice could not restrain C. difficile proline fermentation-dependent growth, suggesting that CP-mediated Zn sequestration along with limited Se restricts C. difficile proline fermentation. Overall, these results highlight how C. difficile colonization depends on the availability of multiple nutrients whose abundances are dynamically influenced by the host response.IMPORTANCEClostridioides difficile infection (CDI) is the leading cause of postantibiotic nosocomial infection. Antibiotic therapy can be successful, yet up to one-third of individuals suffer from recurrent infections. Understanding the mechanisms controlling C. difficile colonization is paramount in designing novel treatments for primary and recurrent CDI. Here, we found that limiting nutrients control C. difficile metabolism during CDI and influence overall pathogen fitness. Specifically, the immune protein CP limits Zn availability and increases transcription of C. difficile genes necessary for proline fermentation. Paradoxically, this leads to reduced C. difficile proline fermentation. This reduced fermentation is due to limited availability of another nutrient required for proline fermentation, Se. Therefore, CP-mediated Zn limitation combined with low Se levels overall reduce C. difficile fitness in the intestines. These results emphasize the complexities of how nutrient availability influences C. difficile colonization and provide insight into critical metabolic processes that drive the pathogen's growth.
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Affiliation(s)
- Christopher A Lopez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - William N Beavers
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Andy Weiss
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Reece J Knippel
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Joseph P Zackular
- Department of Pathology and Laboratory Medicine, Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Protective Immunity, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Walter Chazin
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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Neumann-Schaal M, Jahn D, Schmidt-Hohagen K. Metabolism the Difficile Way: The Key to the Success of the Pathogen Clostridioides difficile. Front Microbiol 2019; 10:219. [PMID: 30828322 PMCID: PMC6384274 DOI: 10.3389/fmicb.2019.00219] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022] Open
Abstract
Strains of Clostridioides difficile cause detrimental diarrheas with thousands of deaths worldwide. The infection process by the Gram-positive, strictly anaerobic gut bacterium is directly related to its unique metabolism, using multiple Stickland-type amino acid fermentation reactions coupled to Rnf complex-mediated sodium/proton gradient formation for ATP generation. Major pathways utilize phenylalanine, leucine, glycine and proline with the formation of 3-phenylproprionate, isocaproate, butyrate, 5-methylcaproate, valerate and 5-aminovalerate. In parallel a versatile sugar catabolism including pyruvate formate-lyase as a central enzyme and an incomplete tricarboxylic acid cycle to prevent unnecessary NADH formation completes the picture. However, a complex gene regulatory network that carefully mediates the continuous adaptation of this metabolism to changing environmental conditions is only partially elucidated. It involves the pleiotropic regulators CodY and SigH, the known carbon metabolism regulator CcpA, the proline regulator PrdR, the iron regulator Fur, the small regulatory RNA CsrA and potentially the NADH-responsive regulator Rex. Here, we describe the current knowledge of the metabolic principles of energy generation by C. difficile and the underlying gene regulatory scenarios.
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Affiliation(s)
- Meina Neumann-Schaal
- Leibniz Institute DSMZ, German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.,Integrated Centre of Systems Biology (BRICS), Braunschweig University of Technology, Braunschweig, Germany
| | - Dieter Jahn
- Integrated Centre of Systems Biology (BRICS), Braunschweig University of Technology, Braunschweig, Germany.,Institute of Microbiology, Braunschweig University of Technology, Braunschweig, Germany
| | - Kerstin Schmidt-Hohagen
- Integrated Centre of Systems Biology (BRICS), Braunschweig University of Technology, Braunschweig, Germany.,Department of Bioinformatics and Biochemistry, Braunschweig University of Technology, Braunschweig, Germany
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