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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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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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3
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Drakesmith H, Zimmermann MB. Another iron in C. difficile's fire. Cell Host Microbe 2024; 32:1-2. [PMID: 38211560 DOI: 10.1016/j.chom.2023.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 12/13/2023] [Indexed: 01/13/2024]
Abstract
Iron is arguably the most important nutrient in the ongoing battle between hosts and bacteria. Recently in Nature, a unique iron storage organelle, the ferrosome, was discovered in the human pathogen Clostridioides difficile.1 But what is the role of ferrosomes and how do they affect bacterial behavior and infection?
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Affiliation(s)
- Hal Drakesmith
- MRC Translational Immune Discovery Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 0EU, UK.
| | - Michael B Zimmermann
- MRC Translational Immune Discovery Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 0EU, UK
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4
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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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5
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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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6
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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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7
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Yamaki J, Chawla S, Tong S, Lozada KA, Yang S. Iron Effects on Clostridioides difficile Toxin Production and Antimicrobial Susceptibilities. Antibiotics (Basel) 2022; 11:537. [PMID: 35625180 PMCID: PMC9137654 DOI: 10.3390/antibiotics11050537] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 03/30/2022] [Accepted: 04/18/2022] [Indexed: 12/10/2022] Open
Abstract
Despite the benefits of red blood cell (RBC) transfusion therapy, it can render patients vulnerable to iron overload. The excess iron deposits in various body tissues cause severe complications and organ damage such as cardiotoxicity and mold infections. Clostridioides difficile infection (CDI) is the most common cause of nosocomial diarrhea among cancer patients and is associated with significant morbidity and mortality. Our study aims to determine the role of iron overload and the effects of iron chelators on CDI. Our results demonstrated that iron (Fe3+) stimulated the growth of C. difficile with increased colony formation units (CFU) in a dose-dependent manner. Exposure to excess iron also increased the gene expression levels of tcdA and tcdB. The production of C. difficile toxin A, necessary for the pathogenesis of C. difficile, was also elevated after iron treatment. In the presence of excess iron, C. difficile becomes less susceptible to metronidazole with significantly elevated minimum inhibitory concentration (MIC) but remains susceptible to vancomycin. Iron-stimulated colony formation and production of C. difficile toxins were effectively diminished by iron chelator deferoxamine co-treatment. Incorporating iron overload status as a potential factor in developing a risk prediction model of CDI and antibiotic treatment response may aid clinical practitioners in optimizing CDI management in oncology patients.
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Affiliation(s)
- Jason Yamaki
- Department of Pharmacy Practice, Chapman University School of Pharmacy, Irvine, CA 92618, USA; (J.Y.); (S.C.)
| | - Swati Chawla
- Department of Pharmacy Practice, Chapman University School of Pharmacy, Irvine, CA 92618, USA; (J.Y.); (S.C.)
| | - Shirley Tong
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA 92618, USA; (S.T.); (K.A.L.)
| | - Kate Alison Lozada
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA 92618, USA; (S.T.); (K.A.L.)
| | - Sun Yang
- Department of Pharmacy Practice, Chapman University School of Pharmacy, Irvine, CA 92618, USA; (J.Y.); (S.C.)
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8
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Chandra H, Sharma KK, Tuovinen OH, Sun X, Shukla P. Pathobionts: mechanisms of survival, expansion, and interaction with host with a focus on Clostridioides difficile. Gut Microbes 2022; 13:1979882. [PMID: 34724858 PMCID: PMC8565823 DOI: 10.1080/19490976.2021.1979882] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Pathobionts are opportunistic microbes that emerge as a result of perturbations in the healthy microbiome due to complex interactions of various genetic, exposomal, microbial, and host factors that lead to their selection and expansion. Their proliferations can aggravate inflammatory manifestations, trigger autoimmune diseases, and lead to severe life-threatening conditions. Current surge in microbiome research is unwinding these complex interplays between disease development and protection against pathobionts. This review summarizes the current knowledge of pathobiont emergence with a focus on Clostridioides difficile and the recent findings on the roles of immune cells such as iTreg cells, Th17 cells, innate lymphoid cells, and cytokines in protection against pathobionts. The review calls for adoption of innovative tools and cutting-edge technologies in clinical diagnostics and therapeutics to provide insights in identification and quantification of pathobionts.
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Affiliation(s)
- Harish Chandra
- Department of Environmental Microbiology, School of Earth and Environmental Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India,Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Krishna Kant Sharma
- Laboratory of Enzymology and Recombinant DNA Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Olli H. Tuovinen
- Department of Microbiology, Ohio State University, Columbus, OH, USA
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA,Xingmin Sun Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Pratyoosh Shukla
- School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, India,Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India,CONTACT Pratyoosh Shukla School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
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9
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Klüber P, Meurer SK, Lambertz J, Schwarz R, Zechel-Gran S, Braunschweig T, Hurka S, Domann E, Weiskirchen R. Depletion of Lipocalin 2 (LCN2) in Mice Leads to Dysbiosis and Persistent Colonization with Segmented Filamentous Bacteria. Int J Mol Sci 2021; 22:ijms222313156. [PMID: 34884961 PMCID: PMC8658549 DOI: 10.3390/ijms222313156] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/26/2021] [Accepted: 12/01/2021] [Indexed: 12/15/2022] Open
Abstract
Lipocalin 2 (LCN2) mediates key roles in innate immune responses. It has affinity for many lipophilic ligands and binds various siderophores, thereby limiting bacterial growth by iron sequestration. Furthermore, LCN2 protects against obesity and metabolic syndrome by interfering with the composition of gut microbiota. Consequently, complete or hepatocyte-specific ablation of the Lcn2 gene is associated with higher susceptibility to bacterial infections. In the present study, we comparatively profiled microbiota in fecal samples of wild type and Lcn2 null mice and show, in contrast to previous reports, that the quantity of DNA in feces of Lcn2 null mice is significantly lower than that in wild type mice (p < 0.001). By using the hypervariable V4 region of the 16S rDNA gene and Next-Generation Sequencing methods, we found a statistically significant change in 16 taxonomic units in Lcn2-/- mice, including eight gender-specific deviations. In particular, members of Clostridium, Escherichia, Helicobacter, Lactococcus, Prevotellaceae_UCG-001 and Staphylococcus appeared to expand in the intestinal tract of knockout mice. Interestingly, the proportion of Escherichia (200-fold) and Staphylococcus (10-fold) as well as the abundance of intestinal bacteria encoding the LCN2-sensitive siderphore enterobactin (entA) was significantly increased in male Lcn2 null mice (743-fold, p < 0.001). This was accompanied by significant higher immune cell infiltration in the ileum as demonstrated by increased immunoreactivity against the pan-leukocyte protein CD45, the lymphocyte transcription factor MUM-1/IRF4, and the macrophage antigen CD68/Macrosialin. In addition, we found a higher expression of mucosal mast cell proteases indicating a higher number of those innate immune cells. Finally, the ileum of Lcn2 null mice displayed a high abundance of segmented filamentous bacteria, which are intimately associated with the mucosal cell layer, provoking epithelial antimicrobial responses and affecting T-helper cell polarization.
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Affiliation(s)
- Patrick Klüber
- German Centre for Infection Research, Institute of Medical Microbiology, Justus-Liebig-University, D-35392 Giessen, Germany; (P.K.); (S.Z.-G.)
| | - Steffen K. Meurer
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH Aachen University Hospital, D-52074 Aachen, Germany; (S.K.M.); (J.L.)
| | - Jessica Lambertz
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH Aachen University Hospital, D-52074 Aachen, Germany; (S.K.M.); (J.L.)
| | - Roman Schwarz
- Labor Mönchengladbach, Medical Care Centre, D-41169 Mönchengladbach, Germany;
| | - Silke Zechel-Gran
- German Centre for Infection Research, Institute of Medical Microbiology, Justus-Liebig-University, D-35392 Giessen, Germany; (P.K.); (S.Z.-G.)
| | - Till Braunschweig
- Institute of Pathology, RWTH Aachen University Hospital, D-52074 Aachen, Germany;
| | - Sabine Hurka
- Institute for Insect Biotechnology, Justus-Liebig-University, D-35392 Giessen, Germany;
| | - Eugen Domann
- German Centre for Infection Research, Institute of Hygiene and Environmental Medicine, Justus-Liebig-University, D-35392 Giessen, Germany
- Correspondence: (E.D.); (R.W.); Tel.: +49-(0)641-99-41280 (E.D.); +49-(0)241-80-88683 (R.W.)
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH Aachen University Hospital, D-52074 Aachen, Germany; (S.K.M.); (J.L.)
- Correspondence: (E.D.); (R.W.); Tel.: +49-(0)641-99-41280 (E.D.); +49-(0)241-80-88683 (R.W.)
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10
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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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11
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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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12
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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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13
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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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14
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Chromosomal Resistance to Metronidazole in Clostridioides difficile Can Be Mediated by Epistasis between Iron Homeostasis and Oxidoreductases. Antimicrob Agents Chemother 2020; 64:AAC.00415-20. [PMID: 32457109 DOI: 10.1128/aac.00415-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/21/2020] [Indexed: 12/17/2022] Open
Abstract
Chromosomal resistance to metronidazole has emerged in clinical Clostridioides difficile isolates, but the genetic mechanisms remain unclear. This is further hindered by the inability to generate spontaneous metronidazole-resistant mutants in the lab to interpret genetic variations in clinical isolates. We therefore constructed a mismatch repair mutator in nontoxigenic ATCC 700057 to survey the mutational landscape for de novo resistance mechanisms. In separate experimental evolutions, the mutator adopted a deterministic path to resistance, with truncation of the ferrous iron transporter FeoB1 as a first-step mechanism of low-level resistance. Deletion of feoB1 in ATCC 700057 reduced the intracellular iron content, appearing to shift cells toward flavodoxin-mediated oxidoreductase reactions, which are less favorable for metronidazole's cellular action. Higher-level resistance evolved from sequential acquisition of mutations to catalytic domains of pyruvate-ferredoxin/flavodoxin oxidoreductase (PFOR; encoded by nifJ), a synonymous codon change to putative xdh (xanthine dehydrogenase; encoded by CD630_31770), likely affecting mRNA stability, and last, frameshift and point mutations that inactivated the iron-sulfur cluster regulator (IscR). Gene silencing of nifJ, xdh, or iscR with catalytically dead Cas9 revealed that resistance involving these genes occurred only when feoB1 was inactivated; i.e., resistance was seen only in the feoB1 deletion mutant and not in the isogenic wild-type (WT) parent. Interestingly, metronidazole resistance in C. difficile infection (CDI)-associated strains carrying mutations in nifJ was reduced upon gene complementation. This observation supports the idea that mutation in PFOR is one mechanism of metronidazole resistance in clinical strains. Our findings indicate that metronidazole resistance in C. difficile is complex, involving multigenetic mechanisms that could intersect with iron-dependent and oxidoreductive metabolic pathways.
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15
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Zhang Y, Sen S, Giedroc DP. Iron Acquisition by Bacterial Pathogens: Beyond Tris-Catecholate Complexes. Chembiochem 2020; 21:1955-1967. [PMID: 32180318 PMCID: PMC7367709 DOI: 10.1002/cbic.201900778] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/06/2020] [Indexed: 12/11/2022]
Abstract
Sequestration of the essential nutrient iron from bacterial invaders that colonize the vertebrate host is a central feature of nutritional immunity and the "fight over transition metals" at the host-pathogen interface. The iron quota for many bacterial pathogens is large, as iron enzymes often make up a significant share of the metalloproteome. Iron enzymes play critical roles in respiration, energy metabolism, and other cellular processes by catalyzing a wide range of oxidation-reduction, electron transfer, and oxygen activation reactions. In this Concept article, we discuss recent insights into the diverse ways that bacterial pathogens acquire this essential nutrient, beyond the well-characterized tris-catecholate FeIII complexes, in competition and cooperation with significant host efforts to cripple these processes. We also discuss pathogen strategies to adapt their metabolism to less-than-optimal iron concentrations, and briefly speculate on what might be an integrated adaptive response to the concurrent limitation of both iron and zinc in the infected host.
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Affiliation(s)
- Yifan Zhang
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405-7102, USA
| | - Sambuddha Sen
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
| | - David P Giedroc
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405-7102, USA
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16
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Zackular JP, Knippel RJ, Lopez CA, Beavers WN, Maxwell CN, Chazin WJ, Skaar EP. ZupT Facilitates Clostridioides difficile Resistance to Host-Mediated Nutritional Immunity. mSphere 2020; 5:e00061-20. [PMID: 32161145 PMCID: PMC7067591 DOI: 10.1128/msphere.00061-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 02/24/2020] [Indexed: 01/18/2023] Open
Abstract
Clostridioides difficile is a spore-forming bacterium that causes severe colitis and is a major public health threat. During infection, C. difficile toxin production results in damage to the epithelium and a hyperinflammatory response. The immune response to CDI leads to robust neutrophil infiltration at the sight of infection and the deployment of numerous antimicrobials. One of the most abundant host immune factors associated with CDI is calprotectin, a metal-chelating protein with potent antimicrobial activity. Calprotectin is essential to the innate immune response to C. difficile and increasing levels of calprotectin correlate with disease severity in both adults and children with CDI. The fact that C. difficile persists in the presence of high levels of calprotectin suggests that this organism may deploy strategies to compete with this potent antimicrobial factor for essential nutrient metals during infection. In this report, we demonstrate that a putative zinc (Zn) transporter, ZupT, is employed by C. difficile to survive calprotectin-mediated metal limitation. ZupT is highly expressed in the presence of calprotectin and is required to protect C. difficile against calprotectin-dependent growth inhibition. When competing against wild-type C. difficile, zupT mutants show a defect in colonization and persistence in a murine model of infection. Together these data demonstrate that C. difficile utilizes a metal import system to combat nutritional immunity during CDI and suggest that strategies targeting nutrient acquisition in C. difficile may have therapeutic potential.IMPORTANCE During infection, pathogenic organisms must acquire essential transition metals from the host environment. Through the process of nutritional immunity, the host employs numerous strategies to restrict these key nutrients from invading pathogens. In this study, we describe a mechanism by which the important human pathogen Clostridioides difficile resists transition-metal limitation by the host. We report that C. difficile utilizes a zinc transporter, ZupT, to compete with the host protein calprotectin for nutrient zinc. Inactivation of this transporter in C. difficile renders this important pathogen sensitive to host-mediated metal restriction and confers a fitness disadvantage during infection. Our study demonstrates that targeting nutrient metal transport proteins in C. difficile is a potential avenue for therapeutic development.
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Affiliation(s)
- Joseph P Zackular
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, 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
| | - 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
| | - C Noel Maxwell
- Department of Biochemistry, Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Walter J Chazin
- Department of Biochemistry, Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Chemistry, 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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17
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Yuan Y, Zallot R, Grove TL, Payan DJ, Martin-Verstraete I, Šepić S, Balamkundu S, Neelakandan R, Gadi VK, Liu CF, Swairjo MA, Dedon PC, Almo SC, Gerlt JA, de Crécy-Lagard V. Discovery of novel bacterial queuine salvage enzymes and pathways in human pathogens. Proc Natl Acad Sci U S A 2019; 116:19126-19135. [PMID: 31481610 PMCID: PMC6754566 DOI: 10.1073/pnas.1909604116] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Queuosine (Q) is a complex tRNA modification widespread in eukaryotes and bacteria that contributes to the efficiency and accuracy of protein synthesis. Eukaryotes are not capable of Q synthesis and rely on salvage of the queuine base (q) as a Q precursor. While many bacteria are capable of Q de novo synthesis, salvage of the prokaryotic Q precursors preQ0 and preQ1 also occurs. With the exception of Escherichia coli YhhQ, shown to transport preQ0 and preQ1, the enzymes and transporters involved in Q salvage and recycling have not been well described. We discovered and characterized 2 Q salvage pathways present in many pathogenic and commensal bacteria. The first, found in the intracellular pathogen Chlamydia trachomatis, uses YhhQ and tRNA guanine transglycosylase (TGT) homologs that have changed substrate specificities to directly salvage q, mimicking the eukaryotic pathway. The second, found in bacteria from the gut flora such as Clostridioides difficile, salvages preQ1 from q through an unprecedented reaction catalyzed by a newly defined subgroup of the radical-SAM enzyme family. The source of q can be external through transport by members of the energy-coupling factor (ECF) family or internal through hydrolysis of Q by a dedicated nucleosidase. This work reinforces the concept that hosts and members of their associated microbiota compete for the salvage of Q precursors micronutrients.
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Affiliation(s)
- Yifeng Yuan
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Rémi Zallot
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Tyler L Grove
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Daniel J Payan
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Isabelle Martin-Verstraete
- Laboratoire de Pathogénèse des Bactéries Anaérobies, Institut Pasteur et Université de Paris, F-75015 Paris, France
| | - Sara Šepić
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Seetharamsingh Balamkundu
- Singapore-MIT Alliance for Research and Technology, Infectious Disease Interdisciplinary Research Group, 138602 Singapore, Singapore
| | - Ramesh Neelakandan
- Singapore-MIT Alliance for Research and Technology, Infectious Disease Interdisciplinary Research Group, 138602 Singapore, Singapore
| | - Vinod K Gadi
- Singapore-MIT Alliance for Research and Technology, Infectious Disease Interdisciplinary Research Group, 138602 Singapore, Singapore
| | - Chuan-Fa Liu
- Singapore-MIT Alliance for Research and Technology, Infectious Disease Interdisciplinary Research Group, 138602 Singapore, Singapore
| | - Manal A Swairjo
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182
- The Viral Information Institute, San Diego State University, San Diego, CA 92182
| | - Peter C Dedon
- Singapore-MIT Alliance for Research and Technology, Infectious Disease Interdisciplinary Research Group, 138602 Singapore, Singapore
- Department of Biological Engineering and Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
- Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Steven C Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461
| | - John A Gerlt
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611;
- University of Florida Genetics Institute, Gainesville, FL 32610
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18
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Berges M, Michel AM, Lassek C, Nuss AM, Beckstette M, Dersch P, Riedel K, Sievers S, Becher D, Otto A, Maaß S, Rohde M, Eckweiler D, Borrero-de Acuña JM, Jahn M, Neumann-Schaal M, Jahn D. Iron Regulation in Clostridioides difficile. Front Microbiol 2018; 9:3183. [PMID: 30619231 PMCID: PMC6311696 DOI: 10.3389/fmicb.2018.03183] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/10/2018] [Indexed: 12/13/2022] Open
Abstract
The response to iron limitation of several bacteria is regulated by the ferric uptake regulator (Fur). The Fur-regulated transcriptional, translational and metabolic networks of the Gram-positive, pathogen Clostridioides difficile were investigated by a combined RNA sequencing, proteomic, metabolomic and electron microscopy approach. At high iron conditions (15 μM) the C. difficile fur mutant displayed a growth deficiency compared to wild type C. difficile cells. Several iron and siderophore transporter genes were induced by Fur during low iron (0.2 μM) conditions. The major adaptation to low iron conditions was observed for the central energy metabolism. Most ferredoxin-dependent amino acid fermentations were significantly down regulated (had, etf, acd, grd, trx, bdc, hbd). The substrates of these pathways phenylalanine, leucine, glycine and some intermediates (phenylpyruvate, 2-oxo-isocaproate, 3-hydroxy-butyryl-CoA, crotonyl-CoA) accumulated, while end products like isocaproate and butyrate were found reduced. Flavodoxin (fldX) formation and riboflavin biosynthesis (rib) were enhanced, most likely to replace the missing ferredoxins. Proline reductase (prd), the corresponding ion pumping RNF complex (rnf) and the reaction product 5-aminovalerate were significantly enhanced. An ATP forming ATPase (atpCDGAHFEB) of the F0F1-type was induced while the formation of a ATP-consuming, proton-pumping V-type ATPase (atpDBAFCEKI) was decreased. The [Fe-S] enzyme-dependent pyruvate formate lyase (pfl), formate dehydrogenase (fdh) and hydrogenase (hyd) branch of glucose utilization and glycogen biosynthesis (glg) were significantly reduced, leading to an accumulation of glucose and pyruvate. The formation of [Fe-S] enzyme carbon monoxide dehydrogenase (coo) was inhibited. The fur mutant showed an increased sensitivity to vancomycin and polymyxin B. An intensive remodeling of the cell wall was observed, Polyamine biosynthesis (spe) was induced leading to an accumulation of spermine, spermidine, and putrescine. The fur mutant lost most of its flagella and motility. Finally, the CRISPR/Cas and a prophage encoding operon were downregulated. Fur binding sites were found upstream of around 20 of the regulated genes. Overall, adaptation to low iron conditions in C. difficile focused on an increase of iron import, a significant replacement of iron requiring metabolic pathways and the restructuring of the cell surface for protection during the complex adaptation phase and was only partly directly regulated by Fur.
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Affiliation(s)
- Mareike Berges
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Annika-Marisa Michel
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Christian Lassek
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Aaron M Nuss
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Michael Beckstette
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Petra Dersch
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Katharina Riedel
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Susanne Sievers
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Dörte Becher
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Andreas Otto
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Sandra Maaß
- Center for Functional Genomics of Microbes (CFGM), Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Denitsa Eckweiler
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | | | - Martina Jahn
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Meina Neumann-Schaal
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
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