51
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Behnsen J, Zhi H, Aron AT, Subramanian V, Santus W, Lee MH, Gerner RR, Petras D, Liu JZ, Green KD, Price SL, Camacho J, Hillman H, Tjokrosurjo J, Montaldo NP, Hoover EM, Treacy-Abarca S, Gilston BA, Skaar EP, Chazin WJ, Garneau-Tsodikova S, Lawrenz MB, Perry RD, Nuccio SP, Dorrestein PC, Raffatellu M. Siderophore-mediated zinc acquisition enhances enterobacterial colonization of the inflamed gut. Nat Commun 2021; 12:7016. [PMID: 34853318 PMCID: PMC8636617 DOI: 10.1038/s41467-021-27297-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 11/09/2021] [Indexed: 11/09/2022] Open
Abstract
Zinc is an essential cofactor for bacterial metabolism, and many Enterobacteriaceae express the zinc transporters ZnuABC and ZupT to acquire this metal in the host. However, the probiotic bacterium Escherichia coli Nissle 1917 (or "Nissle") exhibits appreciable growth in zinc-limited media even when these transporters are deleted. Here, we show that Nissle utilizes the siderophore yersiniabactin as a zincophore, enabling Nissle to grow in zinc-limited media, to tolerate calprotectin-mediated zinc sequestration, and to thrive in the inflamed gut. We also show that yersiniabactin's affinity for iron or zinc changes in a pH-dependent manner, with increased relative zinc binding as the pH increases. Thus, our results indicate that siderophore metal affinity can be influenced by the local environment and reveal a mechanism of zinc acquisition available to commensal and pathogenic Enterobacteriaceae.
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Affiliation(s)
- Judith Behnsen
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
- Department of Microbiology & Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Hui Zhi
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Allegra T Aron
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Vivekanandan Subramanian
- University of Kentucky PharmNMR Center, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - William Santus
- Department of Microbiology & Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Michael H Lee
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Romana R Gerner
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Daniel Petras
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Janet Z Liu
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Keith D Green
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Sarah L Price
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Jose Camacho
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Hannah Hillman
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Joshua Tjokrosurjo
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Nicola P Montaldo
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Evelyn M Hoover
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Sean Treacy-Abarca
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Benjamin A Gilston
- Department of Biochemistry and Chemistry, and Center for Structural Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Walter J Chazin
- Department of Biochemistry and Chemistry, and Center for Structural Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Matthew B Lawrenz
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Robert D Perry
- Department of Microbiology and Immunology, University of Kentucky, Lexington, KY, 40536, USA
| | - Sean-Paul Nuccio
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, 92093, USA
| | - Manuela Raffatellu
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA.
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA.
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, 92093, USA.
- Chiba University-UC San Diego Center for Mucosal Immunology, Allergy, and Vaccines (CU-UCSD cMAV), La Jolla, CA, 92093, USA.
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52
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Insights into the antibacterial mechanism of action of chelating agents by selective deprivation of iron, manganese and zinc. Appl Environ Microbiol 2021; 88:e0164121. [PMID: 34788072 PMCID: PMC8788741 DOI: 10.1128/aem.01641-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial growth and proliferation can be restricted by limiting the availability of metal ions in their environment. Humans sequester iron, manganese, and zinc to help prevent infection by pathogens, a system termed nutritional immunity. Commercially used chelants have high binding affinities with a variety of metal ions, which may lead to antibacterial properties that mimic these innate immune processes. However, the modes of action of many of these chelating agents in bacterial growth inhibition and their selectivity in metal deprivation in cellulo remain ill-defined. We address this shortcoming by examining the effect of 11 chelators on Escherichia coli growth and their impact on the cellular concentration of five metals. The following four distinct effects were uncovered: (i) no apparent alteration in metal composition, (ii) depletion of manganese alongside reductions in iron and zinc levels, (iii) reduced zinc levels with a modest reduction in manganese, and (iv) reduced iron levels coupled with elevated manganese. These effects do not correlate with the absolute known chelant metal ion affinities in solution; however, for at least five chelators for which key data are available, they can be explained by differences in the relative affinity of chelants for each metal ion. The results reveal significant insights into the mechanism of growth inhibition by chelants, highlighting their potential as antibacterials and as tools to probe how bacteria tolerate selective metal deprivation. IMPORTANCE Chelating agents are widely used in industry and consumer goods to control metal availability, with bacterial growth restriction as a secondary benefit for preservation. However, the antibacterial mechanism of action of chelants is largely unknown, particularly with respect to the impact on cellular metal concentrations. The work presented here uncovers distinct metal starvation effects imposed by different chelants on the model Gram-negative bacterium Escherichia coli. The chelators were studied both individually and in pairs, with the majority producing synergistic effects in combinations that maximize antibacterial hostility. The judicious selection of chelants based on contrasting cellular effects should enable reductions in the quantities of chelant required in numerous commercial products and presents opportunities to replace problematic chemistries with biodegradable alternatives.
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53
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Foster AW, Young TR, Chivers PT, Robinson NJ. Protein metalation in biology. Curr Opin Chem Biol 2021; 66:102095. [PMID: 34763208 PMCID: PMC8867077 DOI: 10.1016/j.cbpa.2021.102095] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/08/2021] [Accepted: 10/04/2021] [Indexed: 12/11/2022]
Abstract
Inorganic metals supplement the chemical repertoire of organic molecules, especially proteins. This requires the correct metals to associate with proteins at metalation. Protein mismetalation typically occurs when excesses of unbound metals compete for a binding site ex vivo. However, in biology, excesses of metal-binding sites typically compete for limiting amounts of exchangeable metals. Here, we summarise mechanisms of metal homeostasis that sustain optimal metal availabilities in biology. We describe recent progress to understand metalation by comparing the strength of metal binding to a protein versus the strength of binding to competing sites inside cells.
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Affiliation(s)
- Andrew W Foster
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK; Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | - Tessa R Young
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK; Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | - Peter T Chivers
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK; Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | - Nigel J Robinson
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK; Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
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54
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Price SL, Vadyvaloo V, DeMarco JK, Brady A, Gray PA, Kehl-Fie TE, Garneau-Tsodikova S, Perry RD, Lawrenz MB. Yersiniabactin contributes to overcoming zinc restriction during Yersinia pestis infection of mammalian and insect hosts. Proc Natl Acad Sci U S A 2021; 118:e2104073118. [PMID: 34716262 PMCID: PMC8612365 DOI: 10.1073/pnas.2104073118] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 09/09/2021] [Indexed: 02/04/2023] Open
Abstract
Yersinia pestis causes human plague and colonizes both a mammalian host and a flea vector during its transmission cycle. A key barrier to bacterial infection is the host's ability to actively sequester key biometals (e.g., iron, zinc, and manganese) required for bacterial growth. This is referred to as nutritional immunity. Mechanisms to overcome nutritional immunity are essential virulence factors for bacterial pathogens. Y. pestis produces an iron-scavenging siderophore called yersiniabactin (Ybt) that is required to overcome iron-mediated nutritional immunity and cause lethal infection. Recently, Ybt has been shown to bind to zinc, and in the absence of the zinc transporter ZnuABC, Ybt improves Y. pestis growth in zinc-limited medium. These data suggest that, in addition to iron acquisition, Ybt may also contribute to overcoming zinc-mediated nutritional immunity. To test this hypothesis, we used a mouse model defective in iron-mediated nutritional immunity to demonstrate that Ybt contributes to virulence in an iron-independent manner. Furthermore, using a combination of bacterial mutants and mice defective in zinc-mediated nutritional immunity, we identified calprotectin as the primary barrier for Y. pestis to acquire zinc during infection and that Y. pestis uses Ybt to compete with calprotectin for zinc. Finally, we discovered that Y. pestis encounters zinc limitation within the flea midgut, and Ybt contributes to overcoming this limitation. Together, these results demonstrate that Ybt is a bona fide zinc acquisition mechanism used by Y. pestis to surmount zinc limitation during the infection of both the mammalian and insect hosts.
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Affiliation(s)
- Sarah L Price
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Viveka Vadyvaloo
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164
| | - Jennifer K DeMarco
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, University of Louisville, Louisville, KY 40292
| | - Amanda Brady
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Phoenix A Gray
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Thomas E Kehl-Fie
- Department of Microbiology and Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Champaign, IL 61820
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY 40536
| | - Robert D Perry
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky School of Medicine, Lexington, KY 40506
| | - Matthew B Lawrenz
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202;
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, University of Louisville, Louisville, KY 40292
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55
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Ducret V, Abdou M, Goncalves Milho C, Leoni S, Martin-Pelaud O, Sandoz A, Segovia Campos I, Tercier-Waeber ML, Valentini M, Perron K. Global Analysis of the Zinc Homeostasis Network in Pseudomonas aeruginosa and Its Gene Expression Dynamics. Front Microbiol 2021; 12:739988. [PMID: 34690984 PMCID: PMC8531726 DOI: 10.3389/fmicb.2021.739988] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/24/2021] [Indexed: 11/28/2022] Open
Abstract
Zinc is one of the most important trace elements for life and its deficiency, like its excess, can be fatal. In the bacterial opportunistic pathogen Pseudomonas aeruginosa, Zn homeostasis is not only required for survival, but also for virulence and antibiotic resistance. Thus, the bacterium possesses multiple Zn import/export/storage systems. In this work, we determine the expression dynamics of the entire P. aeruginosa Zn homeostasis network at both transcript and protein levels. Precisely, we followed the switch from a Zn-deficient environment, mimicking the initial immune strategy to counteract bacterial infections, to a Zn-rich environment, representing the phagocyte metal boost used to eliminate an engulfed pathogen. Thanks to the use of the NanoString technology, we timed the global silencing of Zn import systems and the orchestrated induction of Zn export systems. We show that the induction of Zn export systems is hierarchically organized as a function of their impact on Zn homeostasis. Moreover, we identify PA2807 as a novel Zn resistance component in P. aeruginosa and highlight new regulatory links among Zn-homeostasis systems. Altogether, this work unveils a sophisticated and adaptive homeostasis network, which complexity is key in determining a pathogen spread in the environment and during host-colonization.
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Affiliation(s)
- Verena Ducret
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Melina Abdou
- Department of Inorganic and Analytical Chemistry, University of Geneva, Geneva, Switzerland
| | - Catarina Goncalves Milho
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Sara Leoni
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Oriane Martin-Pelaud
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Antoine Sandoz
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Inés Segovia Campos
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland.,Department of Earth Sciences, University of Geneva, Geneva, Switzerland
| | | | - Martina Valentini
- Department of Microbiology and Molecular Medicine, CMU, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Karl Perron
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland.,Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
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56
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Singh S, Diwaker A, Singh BP, Singh RK. Nutritional Immunity, Zinc Sufficiency, and COVID-19 Mortality in Socially Similar European Populations. Front Immunol 2021; 12:699389. [PMID: 34603280 PMCID: PMC8484327 DOI: 10.3389/fimmu.2021.699389] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
The impact of zinc (Zn) sufficiency/supplementation on COVID-19-associated mortality and incidence (SARS-CoV-2 infections) remains unknown. During an infection, the levels of free Zn are reduced as part of “nutritional immunity” to limit the growth and replication of pathogen and the ensuing inflammatory damage. Considering its key role in immune competency and frequently recorded deficiency in large sections of different populations, Zn has been prescribed for both prophylactic and therapeutic purposes in COVID-19 without any corroborating evidence for its protective role. Multiple trials are underway evaluating the effect of Zn supplementation on COVID-19 outcome in patients getting standard of care treatment. However, the trial designs presumably lack the power to identify negative effects of Zn supplementation, especially in the vulnerable groups of elderly and patients with comorbidities (contributing 9 out of 10 deaths; up to >8,000-fold higher mortality). In this study, we have analyzed COVID-19 mortality and incidence (case) data from 23 socially similar European populations with comparable confounders (population: 522.47 million; experiencing up to >150-fold difference in death rates) and at the matching stage of the pandemic (March 12 to June 26, 2020; first wave of COVID-19 incidence and mortality). Our results suggest a positive correlation between populations’ Zn-sufficiency status and COVID-19 mortality [r (23): 0.7893–0.6849, p-value < 0.0003] as well as incidence [r (23):0.8084–0.5658; p-value < 0.005]. The observed association is contrary to what would be expected if Zn sufficiency was protective in COVID-19. Thus, controlled trials or retrospective analyses of the adverse event patients’ data should be undertaken to correctly guide the practice of Zn supplementation in COVID-19.
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Affiliation(s)
- Samer Singh
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Amita Diwaker
- Department of Obstetrics and Gynecology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Brijesh P Singh
- Department of Statistics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Rakesh K Singh
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India
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57
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Li Y, Sharma MR, Koripella RK, Banavali NK, Agrawal RK, Ojha AK. Ribosome hibernation: a new molecular framework for targeting nonreplicating persisters of mycobacteria. MICROBIOLOGY-SGM 2021; 167. [PMID: 33555244 DOI: 10.1099/mic.0.001035] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Treatment of tuberculosis requires a multi-drug regimen administered for at least 6 months. The long-term chemotherapy is attributed in part to a minor subpopulation of nonreplicating Mycobacterium tuberculosis cells that exhibit phenotypic tolerance to antibiotics. The origins of these cells in infected hosts remain unclear. Here we discuss some recent evidence supporting the hypothesis that hibernation of ribosomes in M. tuberculosis, induced by zinc starvation, could be one of the primary mechanisms driving the development of nonreplicating persisters in hosts. We further analyse inconsistencies in previously reported studies to clarify the molecular principles underlying mycobacterial ribosome hibernation.
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Affiliation(s)
- Yunlong Li
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA
| | - Manjuli R Sharma
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA
| | - Ravi K Koripella
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA
| | - Nilesh K Banavali
- Department of Biomedical Sciences, University at Albany, Albany, NY, USA.,Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA
| | - Rajendra K Agrawal
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA.,Department of Biomedical Sciences, University at Albany, Albany, NY, USA
| | - Anil K Ojha
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA.,Department of Biomedical Sciences, University at Albany, Albany, NY, USA
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58
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Edmonds KA, Jordan MR, Giedroc DP. COG0523 proteins: a functionally diverse family of transition metal-regulated G3E P-loop GTP hydrolases from bacteria to man. Metallomics 2021; 13:6327566. [PMID: 34302342 PMCID: PMC8360895 DOI: 10.1093/mtomcs/mfab046] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/15/2021] [Indexed: 01/13/2023]
Abstract
Transition metal homeostasis ensures that cells and organisms obtain sufficient metal to meet cellular demand while dispensing with any excess so as to avoid toxicity. In bacteria, zinc restriction induces the expression of one or more Zur (zinc-uptake repressor)-regulated Cluster of Orthologous Groups (COG) COG0523 proteins. COG0523 proteins encompass a poorly understood sub-family of G3E P-loop small GTPases, others of which are known to function as metallochaperones in the maturation of cobalamin (CoII) and NiII cofactor-containing metalloenzymes. Here, we use genomic enzymology tools to functionally analyse over 80 000 sequences that are evolutionarily related to Acinetobacter baumannii ZigA (Zur-inducible GTPase), a COG0523 protein and candidate zinc metallochaperone. These sequences segregate into distinct sequence similarity network (SSN) clusters, exemplified by the ZnII-Zur-regulated and FeIII-nitrile hydratase activator CxCC (C, Cys; X, any amino acid)-containing COG0523 proteins (SSN cluster 1), NiII-UreG (clusters 2, 8), CoII-CobW (cluster 4), and NiII-HypB (cluster 5). A total of five large clusters that comprise ≈ 25% of all sequences, including cluster 3 which harbors the only structurally characterized COG0523 protein, Escherichia coli YjiA, and many uncharacterized eukaryotic COG0523 proteins. We also establish that mycobacterial-specific protein Y (Mpy) recruitment factor (Mrf), which promotes ribosome hibernation in actinomycetes under conditions of ZnII starvation, segregates into a fifth SSN cluster (cluster 17). Mrf is a COG0523 paralog that lacks all GTP-binding determinants as well as the ZnII-coordinating Cys found in CxCC-containing COG0523 proteins. On the basis of this analysis, we discuss new perspectives on the COG0523 proteins as cellular reporters of widespread nutrient stress induced by ZnII limitation.
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Affiliation(s)
- Katherine A Edmonds
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
| | - Matthew R Jordan
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, 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, USA
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59
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The zinc transporter ZnuABC is critical for the virulence of Chromobacterium violaceum and contributes to diverse zinc-dependent physiological processes. Infect Immun 2021; 89:e0031121. [PMID: 34370507 DOI: 10.1128/iai.00311-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chromobacterium violaceum is a ubiquitous environmental bacterium that causes sporadic life-threatening infections in humans. How C. violaceum acquires zinc to colonize environmental and host niches is unknown. In this work, we demonstrated that C. violaceum employs the zinc uptake system ZnuABC to overcome zinc limitation in the host, ensuring the zinc supply for several physiological demands. Our data indicated that the C. violaceum ZnuABC transporter is encoded in a zur-CV_RS15045-CV_RS15040-znuCBA operon. This operon was repressed by the zinc uptake regulator Zur and derepressed in the presence of the host protein calprotectin (CP) and the synthetic metal chelator EDTA. A ΔznuCBA mutant strain showed impaired growth under these zinc-chelated conditions. Moreover, the deletion of znuCBA provoked a reduction in violacein production, swimming motility, biofilm formation, and bacterial competition. Remarkably, the ΔznuCBA mutant strain was highly attenuated for virulence in an in vivo mouse infection model and showed a low capacity to colonize the liver, grow in the presence of CP, and resist neutrophil killing. Overall, our findings demonstrate that ZnuABC is essential for C. violaceum virulence, contributing to subvert the zinc-based host nutritional immunity.
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60
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Bahr G, González LJ, Vila AJ. Metallo-β-lactamases in the Age of Multidrug Resistance: From Structure and Mechanism to Evolution, Dissemination, and Inhibitor Design. Chem Rev 2021; 121:7957-8094. [PMID: 34129337 PMCID: PMC9062786 DOI: 10.1021/acs.chemrev.1c00138] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Antimicrobial resistance is one of the major problems in current practical medicine. The spread of genes coding for resistance determinants among bacteria challenges the use of approved antibiotics, narrowing the options for treatment. Resistance to carbapenems, last resort antibiotics, is a major concern. Metallo-β-lactamases (MBLs) hydrolyze carbapenems, penicillins, and cephalosporins, becoming central to this problem. These enzymes diverge with respect to serine-β-lactamases by exhibiting a different fold, active site, and catalytic features. Elucidating their catalytic mechanism has been a big challenge in the field that has limited the development of useful inhibitors. This review covers exhaustively the details of the active-site chemistries, the diversity of MBL alleles, the catalytic mechanism against different substrates, and how this information has helped developing inhibitors. We also discuss here different aspects critical to understand the success of MBLs in conferring resistance: the molecular determinants of their dissemination, their cell physiology, from the biogenesis to the processing involved in the transit to the periplasm, and the uptake of the Zn(II) ions upon metal starvation conditions, such as those encountered during an infection. In this regard, the chemical, biochemical and microbiological aspects provide an integrative view of the current knowledge of MBLs.
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Affiliation(s)
- Guillermo Bahr
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Universidad Nacional de Rosario, Ocampo y Esmeralda S/N, 2000 Rosario, Argentina
- Area Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Lisandro J. González
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Universidad Nacional de Rosario, Ocampo y Esmeralda S/N, 2000 Rosario, Argentina
- Area Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Alejandro J. Vila
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Universidad Nacional de Rosario, Ocampo y Esmeralda S/N, 2000 Rosario, Argentina
- Area Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
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61
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Ganguly T, Peterson AM, Kajfasz JK, Abranches J, Lemos JA. Zinc import mediated by AdcABC is critical for colonization of the dental biofilm by Streptococcus mutans in an animal model. Mol Oral Microbiol 2021; 36:214-224. [PMID: 33819383 PMCID: PMC9178666 DOI: 10.1111/omi.12337] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/29/2021] [Accepted: 04/01/2021] [Indexed: 12/18/2022]
Abstract
Trace metals are essential to all domains of life but toxic when found at high concentrations. Although the importance of iron in host-pathogen interactions is firmly established, contemporary studies indicate that other trace metals, including manganese and zinc, are also critical to the infectious process. In this study, we sought to identify and characterize the zinc uptake system(s) of Streptococcus mutans, a keystone pathogen in dental caries and a causative agent of bacterial endocarditis. Different than other pathogenic bacteria, including several streptococci, that encode multiple zinc import systems, bioinformatic analysis indicated that the S. mutans core genome encodes a single, highly conserved, zinc importer commonly known as AdcABC. Inactivation of the genes coding for the metal-binding AdcA (ΔadcA) or both AdcC ATPase and AdcB permease (ΔadcCB) severely impaired the ability of S. mutans to grow under zinc-depleted conditions. Intracellular metal quantifications revealed that both mutants accumulated less zinc when grown in the presence of a subinhibitory concentration of a zinc-specific chelator. Notably, the ΔadcCB strain displayed a severe colonization defect in a rat oral infection model. Both Δadc strains were hypersensitive to high concentrations of manganese, showed reduced peroxide tolerance, and formed less biofilm in sucrose-containing media when cultivated in the presence of the lowest amount of zinc that support their growth, but not when zinc was supplied in excess. Collectively, this study identifies AdcABC as the major high affinity zinc importer of S. mutans and provides preliminary evidence that zinc is a growth-limiting factor within the dental biofilm.
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Affiliation(s)
- Tridib Ganguly
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Alexandra M. Peterson
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Jessica K. Kajfasz
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Jacqueline Abranches
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - José A. Lemos
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, USA
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Goethe E, Gieseke A, Laarmann K, Lührs J, Goethe R. Identification and Characterization of Mycobacterium smegmatis and Mycobacterium avium subsp. paratuberculosis Zinc Transporters. J Bacteriol 2021; 203:JB.00049-21. [PMID: 33722846 PMCID: PMC8117522 DOI: 10.1128/jb.00049-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/04/2021] [Indexed: 11/20/2022] Open
Abstract
Zinc uptake in bacteria is essential to maintain cellular homeostasis and survival. ZnuABC is an important zinc importer of numerous bacterial genera, which is expressed to restore zinc homeostasis when the cytosolic concentration decreases beyond a critical threshold. Upon zinc limitation the fast-growing nonpathogenic organism Mycobacterium smegmatis (MSMEG) as well as the ruminant pathogen M. avium subsp. paratuberculosis (MAP) increases expression of genes encoding ZnuABC homologues, but also of genes encoding other transporters. This suggests an involvement of these transporters in zinc homeostasis. Here we characterized the putative zinc transporters of MSMEG (ZnuABC and ZnuABC2) and MAP (ZnuABC, MptABC, and MAP3774-76). Deletion of either ZnuABC or ZnuABC2 in MSMEG did not lead to growth defects, but to an increased expression of zinc marker genes in MSMEGΔznuABC, indicating cytosolic zinc limitation. However, chromatin immunoprecipitation proved direct binding of the global zinc regulator Zur to promoter regions of both znuABC and znuABC2. Simultaneous deletion of both transporters caused severe growth defects, which could be restored either by homologous complementation with single ZnuABC transporters or supplementation of growth media with zinc but not iron, manganese, cobalt, or magnesium. Heterologous complementation of the double mutant with MAP transporters also resulted in reconstitution of growth. Nonradioactive FluoZinTM-3AM zinc uptake assays directly revealed the competence of all transporters to import zinc. Finally, structural and phylogenetic analyses provided evidence of a novel class of ZnuABC transporters represented by the ZnuABC2 of MSMEG, which is present only in actinobacteria, mainly in the genera Nocardia, Streptomyces and fast growing Mycobacteria IMPORTANCEZinc is necessary for bacterial growth but simultaneously toxic when in excess. Hence, bacterial cells have developed systems to alter intracellular concentration. Regulation of these systems is primarily executed at transcriptional level by regulator proteins which sense femtomolar changes in the zinc level. In environmental and pathogenic mycobacteria zinc starvation induces expression of common zinc import systems such as the ZnuABC transporter, but also of other additional not yet characterized transport systems. In this study, we characterized the role of such systems in zinc transport. We showed that transport systems of both species whose transcription is induced upon zinc starvation can exchangeably restore cellular zinc homeostasis in transporter deficient mutants by transporting zinc into the cell.
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Affiliation(s)
- Elke Goethe
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Ayla Gieseke
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Kristin Laarmann
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Janita Lührs
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Ralph Goethe
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
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Nutritional immunity: the impact of metals on lung immune cells and the airway microbiome during chronic respiratory disease. Respir Res 2021; 22:133. [PMID: 33926483 PMCID: PMC8082489 DOI: 10.1186/s12931-021-01722-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/15/2021] [Indexed: 12/15/2022] Open
Abstract
Nutritional immunity is the sequestration of bioavailable trace metals such as iron, zinc and copper by the host to limit pathogenicity by invading microorganisms. As one of the most conserved activities of the innate immune system, limiting the availability of free trace metals by cells of the immune system serves not only to conceal these vital nutrients from invading bacteria but also operates to tightly regulate host immune cell responses and function. In the setting of chronic lung disease, the regulation of trace metals by the host is often disrupted, leading to the altered availability of these nutrients to commensal and invading opportunistic pathogenic microbes. Similarly, alterations in the uptake, secretion, turnover and redox activity of these vitally important metals has significant repercussions for immune cell function including the response to and resolution of infection. This review will discuss the intricate role of nutritional immunity in host immune cells of the lung and how changes in this fundamental process as a result of chronic lung disease may alter the airway microbiome, disease progression and the response to infection.
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Kang JA, Kwak JS, Park SH, Sim KY, Kim SK, Shin Y, Jung IJ, Yang JI, Chun JS, Park SG. ZIP8 exacerbates collagen-induced arthritis by increasing pathogenic T cell responses. Exp Mol Med 2021; 53:560-571. [PMID: 33795795 PMCID: PMC8102558 DOI: 10.1038/s12276-021-00591-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/20/2020] [Accepted: 01/08/2021] [Indexed: 02/01/2023] Open
Abstract
Zinc is a trace element that is essential for immune responses. Therefore, changes in cellular zinc levels in specific immune cells may influence inflammatory autoimmune diseases, such as rheumatoid arthritis (RA). However, the regulation of zinc mobilization in immune cells and its role in the pathogenesis of RA are not fully understood. Thus, we investigated the roles of zinc transporters in RA pathogenesis. We demonstrated that ZIP8 was specifically upregulated in CD4+ T cells that infiltrated the inflamed joint and that ZIP8 deficiency in CD4+ T cells abrogated collagen-induced arthritis. ZIP8 deficiency dramatically affected zinc influx in effector T cells and profoundly reduced T cell receptor (TCR)-mediated signaling, including NF-κB and MAPK signaling, which are pathways that are involved in T helper (Th) 17 cell differentiation. Taken together, our findings suggest that ZIP8 depletion in CD4+ T cells attenuates TCR signaling due to insufficient cellular zinc, thereby reducing the function of effector CD4+ T cells, including Th17 cells. Our results also suggest that targeting ZIP8 may be a useful strategy to inhibit RA development and pathogenesis.
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Affiliation(s)
- Jung-Ah Kang
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- Cell Logistics Research Center, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- Infectious Disease Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Ji-Sun Kwak
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Sang-Heon Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- Cell Logistics Research Center, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kyu-Young Sim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- Cell Logistics Research Center, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seul Ki Kim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Youngnim Shin
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - In Jung Jung
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Jeong-In Yang
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Jang-Soo Chun
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
- Cell Logistics Research Center, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
- National Creative Research Initiatives Center for Osteoarthritis Pathogenesis, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
| | - Sung-Gyoo Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
- Cell Logistics Research Center, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea.
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Kandari D, Joshi H, Bhatnagar R. Zur: Zinc-Sensing Transcriptional Regulator in a Diverse Set of Bacterial Species. Pathogens 2021; 10:344. [PMID: 33804265 PMCID: PMC8000910 DOI: 10.3390/pathogens10030344] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/02/2021] [Accepted: 03/07/2021] [Indexed: 12/18/2022] Open
Abstract
Zinc (Zn) is the quintessential d block metal, needed for survival in all living organisms. While Zn is an essential element, its excess is deleterious, therefore, maintenance of its intracellular concentrations is needed for survival. The living organisms, during the course of evolution, developed proteins that can track the limitation or excess of necessary metal ions, thus providing survival benefits under variable environmental conditions. Zinc uptake regulator (Zur) is a regulatory transcriptional factor of the FUR superfamily of proteins, abundant among the bacterial species and known for its intracellular Zn sensing ability. In this study, we highlight the roles played by Zur in maintaining the Zn levels in various bacterial species as well as the fact that in recent years Zur has emerged not only as a Zn homeostatic regulator but also as a protein involved directly or indirectly in virulence of some pathogens. This functional aspect of Zur could be exploited in the ventures for the identification of newer antimicrobial targets. Despite extensive research on Zur, the insights into its overall regulon and its moonlighting functions in various pathogens yet remain to be explored. Here in this review, we aim to summarise the disparate functional aspects of Zur proteins present in various bacterial species.
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Affiliation(s)
- Divya Kandari
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India; (D.K.); (H.J.)
| | - Hemant Joshi
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India; (D.K.); (H.J.)
| | - Rakesh Bhatnagar
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India; (D.K.); (H.J.)
- Banaras Hindu University, Banaras 221005, India
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66
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Cuajungco MP, Ramirez MS, Tolmasky ME. Zinc: Multidimensional Effects on Living Organisms. Biomedicines 2021; 9:biomedicines9020208. [PMID: 33671781 PMCID: PMC7926802 DOI: 10.3390/biomedicines9020208] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/03/2021] [Accepted: 02/09/2021] [Indexed: 12/28/2022] Open
Abstract
Zinc is a redox-inert trace element that is second only to iron in abundance in biological systems. In cells, zinc is typically buffered and bound to metalloproteins, but it may also exist in a labile or chelatable (free ion) form. Zinc plays a critical role in prokaryotes and eukaryotes, ranging from structural to catalytic to replication to demise. This review discusses the influential properties of zinc on various mechanisms of bacterial proliferation and synergistic action as an antimicrobial element. We also touch upon the significance of zinc among eukaryotic cells and how it may modulate their survival and death through its inhibitory or modulatory effect on certain receptors, enzymes, and signaling proteins. A brief discussion on zinc chelators is also presented, and chelating agents may be used with or against zinc to affect therapeutics against human diseases. Overall, the multidimensional effects of zinc in cells attest to the growing number of scientific research that reveal the consequential prominence of this remarkable transition metal in human health and disease.
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Wessels I, Fischer HJ, Rink L. Update on the multi-layered levels of zinc-mediated immune regulation. Semin Cell Dev Biol 2020; 115:62-69. [PMID: 33323322 DOI: 10.1016/j.semcdb.2020.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/10/2020] [Accepted: 11/10/2020] [Indexed: 11/15/2022]
Abstract
The significance of zinc for an efficient immune response is well accepted. During zinc deficiency, an increase in the myeloid to lymphoid immune cells ratio was observed. This results in a disturbed balance of pro- and anti-inflammatory processes as well as defects in tolerance during infections. Consequently, instead of efficiently defending the body against invading pathogens, damage of host cells is frequently observed. This explains the increased susceptibility to infections and their severe progression observed for zinc deficient individuals as well as the association of autoimmune diseases with low serum zinc levels. Together with the advances in techniques for investigating cellular development, communication and intracellular metabolism, our understanding of the mechanisms underlying the benefits of zinc for human health and the detriments of zinc deficiency has much improved. As analyses of the zinc status and effects of zinc supplementation were more frequently included into clinical studies, our knowledge of the association of zinc deficiency to a variety of diseases was strongly improved. Still there are several areas in zinc biology that require further in-depth investigation such as the interaction with other nutritional elements, the direct association between zinc transportation, membrane-structure, receptors, and signaling as well as its role in cell degeneration. This article will describe our current understanding of the role of zinc during the immune response focusing on the most recent findings and underlying mechanisms. Research questions that need to be addressed in the future will be discussed as well.
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Affiliation(s)
- Inga Wessels
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
| | - Henrike J Fischer
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
| | - Lothar Rink
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
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68
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Grüngreiff K, Gottstein T, Reinhold D. Zinc Deficiency-An Independent Risk Factor in the Pathogenesis of Haemorrhagic Stroke? Nutrients 2020; 12:E3548. [PMID: 33228216 PMCID: PMC7699494 DOI: 10.3390/nu12113548] [Citation(s) in RCA: 28] [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: 09/07/2020] [Revised: 11/03/2020] [Accepted: 11/16/2020] [Indexed: 12/11/2022] Open
Abstract
Zinc is an essential trace element for human health and plays a fundamental role in metabolic, immunological and many other biological processes. The effects of zinc are based on the intra- and extracellular regulatory function of the zinc ion (Zn2+) and its interactions with proteins. The regulation of cellular zinc homeostasis takes place via a complex network of metal transporters and buffering systems that react to changes in the availability of zinc in nutrition, chronic diseases, infections and many other processes. Zinc deficiency is associated with impairment of numerous metabolic processes, reduced resistance to infections due to impaired immune functions, changes in skin and its appendages and disorders of wound healing and haemostasis. While ischemic heart attacks (myocardial infarction) occur more frequently with meat-based normal diets, haemorrhagic strokes are more frequently observed with vegetarian/vegan diets. The causes are discussed as deficiencies of various micronutrients, such as vitamin B12, vitamin D, various amino acids and also zinc. In the present review, after a description of the functions of zinc and its resorption, a discussion of daily food intake will follow, with a special focus on the importance of food composition and preparation for the zinc balance. The close interrelationships between proteins, especially albumin and zinc will be discussed. Finally, the possible causes and consequences of a zinc deficiency on the blood vessels and blood coagulation are considered.
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Affiliation(s)
- Kurt Grüngreiff
- Clinic of Gastroenterology, City Hospital Magdeburg GmbH, 39130 Magdeburg, Germany;
| | - Thomas Gottstein
- Clinic of Gastroenterology, City Hospital Magdeburg GmbH, 39130 Magdeburg, Germany;
| | - Dirk Reinhold
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke University, 39120 Magdeburg, Germany;
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69
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de Curcio JS, Oliveira LN, Batista MP, Novaes E, de Almeida Soares CM. MiRNAs regulate iron homeostasis in Paracoccidioides brasiliensis. Microbes Infect 2020; 23:104772. [PMID: 33157279 DOI: 10.1016/j.micinf.2020.10.008] [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: 04/09/2020] [Revised: 10/17/2020] [Accepted: 10/27/2020] [Indexed: 11/19/2022]
Abstract
During pathogen interaction with the host, several mechanisms are used to favor or inhibit the infectious process; one is called nutritional immunity, characterized by restriction of micronutrients to pathogens. Several studies on fungi of the Paracoccidioides complex, have demonstrated that these pathogens remodel their metabolic pathways to overcome the hostile condition imposed by the host. However, molecular mechanisms that control the regulation of those metabolic changes are not fully understood. Therefore, this work characterizes the expression profile of miRNAs during iron deprivation and describes metabolic pathways putatively regulated by those molecules. Through analysis of RNAseq, 45 miRNAs were identified and eight presented alterations in the expression profile during iron deprivation. Among the differentially regulated miRNAs, five were more abundant in yeast cells during iron deprivation and interestingly, the analyses of genes potentially regulated by those five miRNAs, pointed to metabolic pathways as oxidative phosphorylation, altered in response to iron deprivation. In addition, miRNAs with more abundance in iron presence, have as target genes encoding transcriptional factors related to iron homeostasis and uptake. Therefore, we suggest that miRNAs produced by Paracoccidioides brasiliensis may contribute to the adaptive responses of this fungus in iron starvation environment.
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Affiliation(s)
- Juliana S de Curcio
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Campus II Samambaia, CEP: 74690-900, Goiânia, Goiás, Brazil
| | - Lucas Nojosa Oliveira
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Campus II Samambaia, CEP: 74690-900, Goiânia, Goiás, Brazil
| | - Mariana P Batista
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Campus II Samambaia, CEP: 74690-900, Goiânia, Goiás, Brazil
| | - Evandro Novaes
- Departamento de Biologia, Universidade Federal de Lavras, Minas Gerais, CEP: 37200-000, Brazil
| | - Célia Maria de Almeida Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Campus II Samambaia, CEP: 74690-900, Goiânia, Goiás, Brazil.
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70
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von Pein JB, Stocks CJ, Schembri MA, Kapetanovic R, Sweet MJ. An alloy of zinc and innate immunity: Galvanising host defence against infection. Cell Microbiol 2020; 23:e13268. [PMID: 32975847 DOI: 10.1111/cmi.13268] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 12/16/2022]
Abstract
Innate immune cells such as macrophages and neutrophils initiate protective inflammatory responses and engage antimicrobial responses to provide frontline defence against invading pathogens. These cells can both restrict the availability of certain transition metals that are essential for microbial growth and direct toxic concentrations of metals towards pathogens as antimicrobial responses. Zinc is important for the structure and function of many proteins, however excess zinc can be cytotoxic. In recent years, several studies have revealed that innate immune cells can deliver toxic concentrations of zinc to intracellular pathogens. In this review, we discuss the importance of zinc status during infectious disease and the evidence for zinc intoxication as an innate immune antimicrobial response. Evidence for pathogen subversion of this response is also examined. The likely mechanisms, including the involvement of specific zinc transporters that facilitate delivery of zinc by innate immune cells for metal ion poisoning of pathogens are also considered. Precise mechanisms by which excess levels of zinc can be toxic to microorganisms are then discussed, particularly in the context of synergy with other antimicrobial responses. Finally, we highlight key unanswered questions in this emerging field, which may offer new opportunities for exploiting innate immune responses for anti-infective development.
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Affiliation(s)
- Jessica B von Pein
- Institute for Molecular Bioscience (IMB), The University of Queensland, St. Lucia, Queensland, Australia.,IMB Centre for Inflammation and Disease Research, The University of Queensland, St. Lucia, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, Australia
| | - Claudia J Stocks
- Institute for Molecular Bioscience (IMB), The University of Queensland, St. Lucia, Queensland, Australia.,IMB Centre for Inflammation and Disease Research, The University of Queensland, St. Lucia, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, Australia
| | - Mark A Schembri
- Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, Australia.,School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Queensland, Australia
| | - Ronan Kapetanovic
- Institute for Molecular Bioscience (IMB), The University of Queensland, St. Lucia, Queensland, Australia.,IMB Centre for Inflammation and Disease Research, The University of Queensland, St. Lucia, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, Australia
| | - Matthew J Sweet
- Institute for Molecular Bioscience (IMB), The University of Queensland, St. Lucia, Queensland, Australia.,IMB Centre for Inflammation and Disease Research, The University of Queensland, St. Lucia, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, Australia
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71
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Bellotti D, Rowińska-Żyrek M, Remelli M. Novel insights into the metal binding ability of ZinT periplasmic protein from Escherichia coli and Salmonella enterica. Dalton Trans 2020; 49:9393-9403. [PMID: 32588863 DOI: 10.1039/d0dt01626h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The ZinT mediated Zn(ii) uptake is one of the major differences in the metabolism of human and bacterial cells that can be challenged when looking for possible highly selective metal-based therapeutics. ZinT is a 216-amino acid periplasmic protein expressed by Gram-negative bacteria, which shuttles Zn(ii) ions to the ZnuABC transporter under zinc-limiting conditions. The suggested metal-binding sites of ZinT correspond to a domain containing three highly conserved histidine residues (His 167, 176 and 178) and to the N-terminal histidine-rich loop HGHHXH (residues 24-29). The coordination chemistry of the ZinT complexes with Zn(ii) and Cu(ii) has been investigated. The present work is focused on the protected peptides Ac-24HGHHSH29-NH2 and Ac-166DHIIAPRKSSHFH178-NH2 as models for the putative metal binding sites of ZinT from Escherichia coli (EcZinT), and Ac-24HGHHAH29-NH2 and Ac-166DHIIAPRKSAHFH178-NH2 from the ZinT protein expressed by Salmonella enterica sv. Typhimurium (SeZinT). The investigated peptides are able to form stable mono-nuclear complexes where the histidine residues represent the principal metal anchoring sites. The ZnuA (a periplasmic component of the ZnuABC transporter) metal binding site exhibits higher affinity for Zn(ii) than ZinT, suggesting that the interaction of the two proteins through the formation of a binary complex may involve the metal transfer from ZinT to ZnuA. In contrast, this would not occur in Cu(ii), since the ZinT complexes are more stable. Furthermore, at acidic pH, where the antimicrobial peptide calcitermin is biologically active, it also binds the metal ions with higher affinity than ZinT, representing a possible efficient competitor and antagonist of ZinT in the host human organism.
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Affiliation(s)
- Denise Bellotti
- Department of Chemical and Pharmaceutical Sciences, University of Ferrara, Luigi Borsari 46, 44121 Ferrara, Italy.
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Histidine Utilization Is a Critical Determinant of Acinetobacter Pathogenesis. Infect Immun 2020; 88:IAI.00118-20. [PMID: 32341119 DOI: 10.1128/iai.00118-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/20/2020] [Indexed: 12/14/2022] Open
Abstract
Acinetobacter baumannii is a nosocomial pathogen capable of causing a range of diseases, including respiratory and urinary tract infections and bacteremia. Treatment options are limited due to the increasing rates of antibiotic resistance, underscoring the importance of identifying new targets for antimicrobial development. During infection, A. baumannii must acquire nutrients for replication and survival. These nutrients include carbon- and nitrogen-rich molecules that are needed for bacterial growth. One possible nutrient source within the host is amino acids, which can be utilized for protein synthesis or energy generation. Of these, the amino acid histidine is among the most energetically expensive for bacteria to synthesize; therefore, scavenging histidine from the environment is likely advantageous. We previously identified the A. baumannii histidine utilization (Hut) system as being linked to nutrient zinc homeostasis, but whether the Hut system is important for histidine-dependent energy generation or vertebrate colonization is unknown. Here, we demonstrate that the Hut system is conserved among pathogenic Acinetobacter and regulated by the transcriptional repressor HutC. In addition, the Hut system is required for energy generation using histidine as a carbon and nitrogen source. Histidine was also detected extracellularly in the murine lung, demonstrating that it is bioavailable during infection. Finally, the ammonia-releasing enzyme HutH is required for acquiring nitrogen from histidine in vitro, and strains inactivated for hutH are severely attenuated in a murine model of pneumonia. These results suggest that bioavailable histidine in the lung promotes Acinetobacter pathogenesis and that histidine serves as a crucial nitrogen source during infection.
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Riedelberger M, Penninger P, Tscherner M, Hadriga B, Brunnhofer C, Jenull S, Stoiber A, Bourgeois C, Petryshyn A, Glaser W, Limbeck A, Lynes MA, Schabbauer G, Weiss G, Kuchler K. Type I Interferons Ameliorate Zinc Intoxication of Candida glabrata by Macrophages and Promote Fungal Immune Evasion. iScience 2020; 23:101121. [PMID: 32428860 PMCID: PMC7232100 DOI: 10.1016/j.isci.2020.101121] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/09/2020] [Accepted: 04/29/2020] [Indexed: 12/16/2022] Open
Abstract
Host and fungal pathogens compete for metal ion acquisition during infectious processes, but molecular mechanisms remain largely unknown. Here, we show that type I interferons (IFNs-I) dysregulate zinc homeostasis in macrophages, which employ metallothionein-mediated zinc intoxication of pathogens as fungicidal response. However, Candida glabrata can escape immune surveillance by sequestering zinc into vacuoles. Interestingly, zinc-loading is inhibited by IFNs-I, because a Janus kinase 1 (JAK1)-dependent suppression of zinc homeostasis affects zinc distribution in macrophages as well as generation of reactive oxygen species (ROS). In addition, systemic fungal infections elicit IFN-I responses that suppress splenic zinc homeostasis, thereby altering macrophage zinc pools that otherwise exert fungicidal actions. Thus, IFN-I signaling inadvertently increases fungal fitness both in vitro and in vivo during fungal infections. Our data reveal an as yet unrecognized role for zinc intoxication in antifungal immunity and suggest that interfering with host zinc homeostasis may offer therapeutic options to treat invasive fungal infections.
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Affiliation(s)
- Michael Riedelberger
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Philipp Penninger
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Michael Tscherner
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Bernhard Hadriga
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Carina Brunnhofer
- Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria
| | - Sabrina Jenull
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Anton Stoiber
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Christelle Bourgeois
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Andriy Petryshyn
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Walter Glaser
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Andreas Limbeck
- Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria
| | - Michael A Lynes
- Department of Molecular and Cell Biology, University of Connecticut, CT, USA
| | - Gernot Schabbauer
- Institute for Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Guenter Weiss
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, and Pneumology, Medical University of Innsbruck, Innsbruck, Austria
| | - Karl Kuchler
- Medical University of Vienna, Center for Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Vienna, Austria.
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74
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Grim KP, Radin JN, Solórzano PKP, Morey JR, Frye KA, Ganio K, Neville SL, McDevitt CA, Kehl-Fie TE. Intracellular Accumulation of Staphylopine Can Sensitize Staphylococcus aureus to Host-Imposed Zinc Starvation by Chelation-Independent Toxicity. J Bacteriol 2020; 202:e00014-20. [PMID: 32071094 PMCID: PMC7148132 DOI: 10.1128/jb.00014-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023] Open
Abstract
The host restricts the availability of zinc to prevent infection. To overcome this defense, Staphylococcus aureus and Pseudomonas aeruginosa rely on zincophore-dependent zinc importers. Synthesis of the zincophore staphylopine by S. aureus and its import are both necessary for the bacterium to cause infection. In this study, we sought to elucidate how loss of zincophore efflux impacts bacterial resistance to host-imposed zinc starvation. In culture and during infection, mutants lacking CntE, the staphylopine efflux pump, were more sensitive to zinc starvation imposed by the metal-binding immune effector calprotectin than those lacking the ability to import staphylopine. However, disruption of staphylopine synthesis reversed the enhanced sensitivity phenotype of the ΔcntE mutant to calprotectin, indicating that intracellular toxicity of staphylopine is more detrimental than the impaired ability to acquire zinc. Unexpectedly, intracellular accumulation of staphylopine does not increase the expression of metal importers or alter cellular metal concentrations, suggesting that, contrary to prevailing models, the toxicity associated with staphylopine is not strictly due to intracellular chelation of metals. As P. aeruginosa and other pathogens produce zincophores with similar chemistry, our observations on the crucial importance of zincophore efflux are likely to be broadly relevant.IMPORTANCEStaphylococcus aureus and many other bacterial pathogens rely on metal-binding small molecules to obtain the essential metal zinc during infection. In this study, we reveal that export of these small molecules is critical for overcoming host-imposed metal starvation during infection and prevents toxicity due to accumulation of the metal-binding molecule within the cell. Surprisingly, we found that intracellular toxicity of the molecule is not due to chelation of cellular metals.
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Affiliation(s)
- Kyle P Grim
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Jana N Radin
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Paola K Párraga Solórzano
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Departmento de Ciencias de la Vida, Universidad de las Fuerzas Armadas ESPE, Sangolquí, Ecuador
| | - Jacqueline R Morey
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Katie A Frye
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Katherine Ganio
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Stephanie L Neville
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Christopher A McDevitt
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Thomas E Kehl-Fie
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
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75
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Gopalakrishna KP, Hand TW. Influence of Maternal Milk on the Neonatal Intestinal Microbiome. Nutrients 2020; 12:E823. [PMID: 32244880 PMCID: PMC7146310 DOI: 10.3390/nu12030823] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/13/2020] [Accepted: 03/18/2020] [Indexed: 02/07/2023] Open
Abstract
The intestinal microbiome plays an important role in maintaining health throughout life. The microbiota develops progressively after birth and is influenced by many factors, including the mode of delivery, antibiotics, and diet. Maternal milk is critically important to the development of the neonatal intestinal microbiota. Different bioactive components of milk, such as human milk oligosaccharides, lactoferrin, and secretory immunoglobulins, modify the composition of the neonatal microbiota. In this article, we review the role of each of these maternal milk-derived bioactive factors on the microbiota and how this modulation of intestinal bacteria shapes health, and disease.
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Affiliation(s)
| | - Timothy W. Hand
- R. K. Mellon Institute for Pediatric Research, UPMC Children’s Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA 15217, USA;
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76
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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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