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Peng ED, Lyman LR, Schmitt MP. Identification and characterization of zinc importers in Corynebacterium diphtheriae. J Bacteriol 2024; 206:e0012424. [PMID: 38809016 PMCID: PMC11332173 DOI: 10.1128/jb.00124-24] [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: 03/25/2024] [Accepted: 05/03/2024] [Indexed: 05/30/2024] Open
Abstract
Corynebacterium diphtheriae is the causative agent of diphtheria, a severe respiratory disease in humans. C. diphtheriae colonizes the human upper respiratory tract, where it acquires zinc, an essential metal required for survival in the host. While the mechanisms for zinc transport by C. diphtheriae are not well characterized, four putative zinc ABC-type transporter loci were recently identified in strain 1737: iutABCD/E (iut), znuACB (znu), nikABCD1 (nik1), and nikABCD2 (nik2). A mutant deleted for all four loci (Δ4) exhibited similar growth to that of the wild-type strain in a zinc-limited medium, suggesting there are additional zinc transporters. Two additional gene loci predicted to be associated with metal import, mntABCD (mnt) and sidAB (sid), were deleted in the Δ4 mutant to construct a new mutant designated Δ6. The C. diphtheriae Δ6 mutant exhibited significantly reduced growth under zinc limitation relative to the wild type, suggesting a deficiency in zinc acquisition. Strains retaining the iut, znu, mnt, or sid loci grew to near-wild-type levels in the absence of the other five loci, indicating that each of these transporters may be involved in zinc uptake. Plasmid complementation with cloned iut, znu, mnt, or nik1 loci also enhanced the growth of the Δ6 mutant. Quantification of intracellular zinc content by inductively coupled plasma mass spectrometry was consistent with reduced zinc uptake by Δ6 relative to the wild type and further supports a zinc uptake function for the transporters encoded by iut, znu, and mnt. This study demonstrates that C. diphtheriae zinc transport is complex and involves multiple zinc uptake systems.IMPORTANCEZinc is a critical nutrient for all forms of life, including human bacterial pathogens. Thus, the tools that bacteria use to acquire zinc from host sources are crucial for pathogenesis. While potential candidates for zinc importers have been identified in Corynebacterium diphtheriae from gene expression studies, to date, no study has clearly demonstrated this function for any of the putative transporters. We show that C. diphtheriae encodes at least six loci associated with zinc import, underscoring the extent of redundancy for zinc acquisition. Furthermore, we provide evidence that a previously studied manganese-regulated importer can also function in zinc import. This study builds upon our knowledge of bacterial zinc transport mechanisms and identifies potential targets for future diphtheria vaccine candidates.
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Affiliation(s)
- Eric D. Peng
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Lindsey R. Lyman
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Michael P. Schmitt
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
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2
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Gonzalez de Vega R, Clases D, Cunningham BA, Ganio K, Neville SL, McDevitt CA, Doble PA. Spatial distribution of trace metals and associated transport proteins during bacterial infection. Anal Bioanal Chem 2024; 416:2783-2796. [PMID: 38057634 DOI: 10.1007/s00216-023-05068-w] [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: 09/28/2023] [Revised: 11/08/2023] [Accepted: 11/20/2023] [Indexed: 12/08/2023]
Abstract
Innate immune systems alter the concentrations of trace elements in host niches in response to invading pathogens during infection. This work reports the interplay between d-block metal ions and their associated biomolecules using hyphenated elemental techniques to spatially quantify both elemental distributions and the abundance of specific transport proteins. Here, lung tissues were collected for analyses from naïve and Streptococcus pneumoniae-infected mice fed on a zinc-restricted or zinc-supplemented diet. Spatiotemporal distributions of manganese (55Mn), iron (56Fe), copper (63Cu), and zinc (66Zn) were determined by quantitative laser ablation-inductively coupled plasma-mass spectrometry. The murine transport proteins ZIP8 and ZIP14, which are associated with zinc transport, were also imaged by incorporation of immunohistochemistry techniques into the analytical workflow. Collectively, this work demonstrates the potential of a single instrumental platform suitable for multiplex analyses of tissues and labelled antibodies to investigate complex elemental interactions at the host-pathogen interface. Further, these methods have the potential for broad application to investigations of biological pathways where concomitant measurement of elements and biomolecules is crucial to understand the basis of disease and aid in development of new therapeutic approaches.
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Affiliation(s)
- Raquel Gonzalez de Vega
- The Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales, Australia
- TESLA-Analytical Chemistry, Institute of Chemistry, University of Graz, Graz, Austria
| | - David Clases
- The Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales, Australia
- Nano Micro LAB, Institute of Chemistry, University of Graz, Graz, Austria
| | - Bliss A Cunningham
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - 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
| | - Philip A Doble
- The Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales, Australia.
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3
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Villa M, Wu J, Hansen S, Pahnke J. Emerging Role of ABC Transporters in Glia Cells in Health and Diseases of the Central Nervous System. Cells 2024; 13:740. [PMID: 38727275 PMCID: PMC11083179 DOI: 10.3390/cells13090740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/15/2024] [Accepted: 04/20/2024] [Indexed: 05/13/2024] Open
Abstract
ATP-binding cassette (ABC) transporters play a crucial role for the efflux of a wide range of substrates across different cellular membranes. In the central nervous system (CNS), ABC transporters have recently gathered significant attention due to their pivotal involvement in brain physiology and neurodegenerative disorders, such as Alzheimer's disease (AD). Glial cells are fundamental for normal CNS function and engage with several ABC transporters in different ways. Here, we specifically highlight ABC transporters involved in the maintenance of brain homeostasis and their implications in its metabolic regulation. We also show new aspects related to ABC transporter function found in less recognized diseases, such as Huntington's disease (HD) and experimental autoimmune encephalomyelitis (EAE), as a model for multiple sclerosis (MS). Understanding both their impact on the physiological regulation of the CNS and their roles in brain diseases holds promise for uncovering new therapeutic options. Further investigations and preclinical studies are warranted to elucidate the complex interplay between glial ABC transporters and physiological brain functions, potentially leading to effective therapeutic interventions also for rare CNS disorders.
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Affiliation(s)
- Maria Villa
- Translational Neurodegeneration Research and Neuropathology Lab, Department of Clinical Medicine (KlinMed), Medical Faculty, University of Oslo (UiO) and Section of Neuropathology Research, Department of Pathology (PAT), Clinics for Laboratory Medicine (KLM), Oslo University Hospital (OUS), Sognsvannsveien 20, NO-0372 Oslo, Norway
| | - Jingyun Wu
- Translational Neurodegeneration Research and Neuropathology Lab, Department of Clinical Medicine (KlinMed), Medical Faculty, University of Oslo (UiO) and Section of Neuropathology Research, Department of Pathology (PAT), Clinics for Laboratory Medicine (KLM), Oslo University Hospital (OUS), Sognsvannsveien 20, NO-0372 Oslo, Norway
| | - Stefanie Hansen
- Translational Neurodegeneration Research and Neuropathology Lab, Department of Clinical Medicine (KlinMed), Medical Faculty, University of Oslo (UiO) and Section of Neuropathology Research, Department of Pathology (PAT), Clinics for Laboratory Medicine (KLM), Oslo University Hospital (OUS), Sognsvannsveien 20, NO-0372 Oslo, Norway
| | - Jens Pahnke
- Translational Neurodegeneration Research and Neuropathology Lab, Department of Clinical Medicine (KlinMed), Medical Faculty, University of Oslo (UiO) and Section of Neuropathology Research, Department of Pathology (PAT), Clinics for Laboratory Medicine (KLM), Oslo University Hospital (OUS), Sognsvannsveien 20, NO-0372 Oslo, Norway
- Institute of Nutritional Medicine (INUM)/Lübeck Institute of Dermatology (LIED), University of Lübeck (UzL) and University Medical Center Schleswig-Holstein (UKSH), Ratzeburger Allee 160, D-23538 Lübeck, Germany
- Department of Pharmacology, Faculty of Medicine, University of Latvia (LU), Jelgavas iela 3, LV-1004 Rīga, Latvia
- School of Neurobiology, Biochemistry and Biophysics, The Georg S. Wise Faculty of Life Sciences, Tel Aviv University (TAU), Tel Aviv IL-6997801, Israel
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4
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Zheng Y, Duan Z, Wu Y, Luo Y, Peng X, Wu J. Analysis of the Cadmium Removal Mechanism of Human Gut Bacteria Enterococcus faecalis Strain ATCC19433 from a Genomic Perspective. Biol Trace Elem Res 2024:10.1007/s12011-024-04169-6. [PMID: 38602649 DOI: 10.1007/s12011-024-04169-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 04/01/2024] [Indexed: 04/12/2024]
Abstract
Cadmium (Cd) is one of the most well-known toxic metals capable of entering the human body via the food chain, leading to serious health problems. Human gut microbes play a pivotal role in controlling Cd bioavailability and toxicity within the human gastrointestinal tract, primarily due to their capacity for Cd adsorption and metabolism. In this work, a Cd-resistant bacterial strain, Enterococcus faecalis strain ATCC19433 was isolated from human gut microbiota. Cd binding assays and comprehensive characterization analyses were performed, revealing the ability of strain ATCC19433 to remove Cd from the solution. Cd adsorption primarily occurred on the bacterial cell walls, which was ascribed to the exciting of functional groups on the bacterial surfaces, containing alkyl, amide II, and phosphate groups; meanwhile, Cd could enter cells, probably through transport channels or via diffusion. These results indicated that Cd removal by the strain was predominantly dependent on biosorption and bioaccumulation. Whole-genome sequencing analyses further suggested the probable mechanisms of biosorption and bioaccumulation, including Cd transport by transporter proteins, active efflux of Cd by cadmium efflux pumps, and mitigating oxidative stress-induced cell damage by DNA repair proteases. This study evaluated the Cd removal capability and mechanism of Enterococcus faecalis strain ATCC19433 while annotating the genetic functions related to Cd removal, which may facilitate the development of potential human gut strains for the removal of Cd.
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Affiliation(s)
- Yu Zheng
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
- Guizhou Ecological Environment Resources Management Co., LTD, Guiyang, 550009, China
| | - Zhibin Duan
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
- School of Public Health, Zunyi Medical University, Zunyi, 563006, China
| | - Yonggui Wu
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
- Guizhou Hostile Environment Ecological Restoration Technology Engineering Research Centre, Guiyang, 550025, China.
- Guizhou Karst Environmental Ecosystem Observation and Research Station, Ministry of Education, Guiyang, 550025, China.
| | - Yang Luo
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Xiaoyu Peng
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Jianye Wu
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
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5
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Aziz I, Kayastha K, Kaltwasser S, Vonck J, Welsch S, Murphy BJ, Kahnt J, Wu D, Wagner T, Shima S, Ermler U. Structural and mechanistic basis of the central energy-converting methyltransferase complex of methanogenesis. Proc Natl Acad Sci U S A 2024; 121:e2315568121. [PMID: 38530900 PMCID: PMC10998594 DOI: 10.1073/pnas.2315568121] [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: 09/13/2023] [Accepted: 02/24/2024] [Indexed: 03/28/2024] Open
Abstract
Methanogenic archaea inhabiting anaerobic environments play a crucial role in the global biogeochemical material cycle. The most universal electrogenic reaction of their methane-producing energy metabolism is catalyzed by N 5-methyl-tetrahydromethanopterin: coenzyme M methyltransferase (MtrABCDEFGH), which couples the vectorial Na+ transport with a methyl transfer between the one-carbon carriers tetrahydromethanopterin and coenzyme M via a vitamin B12 derivative (cobamide) as prosthetic group. We present the 2.08 Å cryo-EM structure of Mtr(ABCDEFG)3 composed of the central Mtr(ABFG)3 stalk symmetrically flanked by three membrane-spanning MtrCDE globes. Tetraether glycolipids visible in the map fill gaps inside the multisubunit complex. Putative coenzyme M and Na+ were identified inside or in a side-pocket of a cytoplasmic cavity formed within MtrCDE. Its bottom marks the gate of the transmembrane pore occluded in the cryo-EM map. By integrating Alphafold2 information, functionally competent MtrA-MtrH and MtrA-MtrCDE subcomplexes could be modeled and thus the methyl-tetrahydromethanopterin demethylation and coenzyme M methylation half-reactions structurally described. Methyl-transfer-driven Na+ transport is proposed to be based on a strong and weak complex between MtrCDE and MtrA carrying vitamin B12, the latter being placed at the entrance of the cytoplasmic MtrCDE cavity. Hypothetically, strongly attached methyl-cob(III)amide (His-on) carrying MtrA induces an inward-facing conformation, Na+ flux into the membrane protein center and finally coenzyme M methylation while the generated loosely attached (or detached) MtrA carrying cob(I)amide (His-off) induces an outward-facing conformation and an extracellular Na+ outflux. Methyl-cob(III)amide (His-on) is regenerated in the distant active site of the methyl-tetrahydromethanopterin binding MtrH implicating a large-scale shuttling movement of the vitamin B12-carrying domain.
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Affiliation(s)
- Iram Aziz
- Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Kanwal Kayastha
- Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Susann Kaltwasser
- Central Electron Microscopy Facility, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Janet Vonck
- Structural Biology, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Sonja Welsch
- Central Electron Microscopy Facility, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Bonnie J. Murphy
- Redox and Metalloprotein Research Group, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Jörg Kahnt
- Max Planck Institute for Terrestrial Microbiology, MarburgD-35043, Germany
| | - Di Wu
- Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
| | - Tristan Wagner
- Max Planck Institute for Marine Microbiology, BremenD-28359, Germany
| | - Seigo Shima
- Max Planck Institute for Terrestrial Microbiology, MarburgD-35043, Germany
| | - Ulrich Ermler
- Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt am MainD-60438, Germany
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6
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Ganio K, Nasreen M, Yang Z, Maunders EA, Luo Z, Hossain SI, Ngu DHY, Ellis D, Gu J, Neville SL, Wilksch J, Gunn AP, Whittall JJ, Kobe B, Deplazes E, Kappler U, McDevitt CA. Hfe Permease and Haemophilus influenzae Manganese Homeostasis. ACS Infect Dis 2024; 10:436-452. [PMID: 38240689 PMCID: PMC10863617 DOI: 10.1021/acsinfecdis.3c00407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 02/10/2024]
Abstract
Haemophilus influenzae is a commensal of the human upper respiratory tract that can infect diverse host niches due, at least in part, to its ability to withstand both endogenous and host-mediated oxidative stresses. Here, we show that hfeA, a gene previously linked to iron import, is essential for H. influenzae manganese recruitment via the HfeBCD transporter. Structural analyses show that metal binding in HfeA uses a unique mechanism that involves substantial rotation of the C-terminal lobe of the protein. Disruption of hfeA reduced H. influenzae manganese acquisition and was associated with decreased growth under aerobic conditions, impaired manganese-superoxide dismutase activity, reduced survival in macrophages, and changes in biofilm production in the presence of superoxide. Collectively, this work shows that HfeA contributes to H. influenzae manganese acquisition and virulence attributes. High conservation of the hfeABCD permease in Haemophilus species suggests that it may serve similar roles in other pathogenic Pasteurellaceae.
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Affiliation(s)
- Katherine Ganio
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Marufa Nasreen
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
| | - Zihao Yang
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
| | - Eve A. Maunders
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Zhenyao Luo
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
- Institute
for Molecular Bioscience, The University
of Queensland, St Lucia, Queensland 4072, Australia
| | - Sheikh Imamul Hossain
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- School
of Life Sciences, University of Technology
Sydney, Ultimo, New South Wales 2007, Australia
| | - Dalton H. Y. Ngu
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
- Institute
for Molecular Bioscience, The University
of Queensland, St Lucia, Queensland 4072, Australia
| | - Daniel Ellis
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
| | - Jin Gu
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
| | - Stephanie L. Neville
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Jonathan Wilksch
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Adam P. Gunn
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Jonathan J. Whittall
- School of
Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Boštjan Kobe
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
- Institute
for Molecular Bioscience, The University
of Queensland, St Lucia, Queensland 4072, Australia
| | - Evelyne Deplazes
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- School
of Life Sciences, University of Technology
Sydney, Ultimo, New South Wales 2007, Australia
| | - Ulrike Kappler
- School
of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
- Australian
Infectious Diseases Research Centre, The
University of Queensland, St Lucia, Queensland 4072, Australia
| | - Christopher A. McDevitt
- Department
of Microbiology and Immunology, the Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
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7
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Maunders EA, Giles MW, Ganio K, Cunningham BA, Bennett-Wood V, Cole GB, Ng D, Lai CC, Neville SL, Moraes TF, McDevitt CA, Tan A. Zinc acquisition and its contribution to Klebsiella pneumoniae virulence. Front Cell Infect Microbiol 2024; 13:1322973. [PMID: 38249299 PMCID: PMC10797113 DOI: 10.3389/fcimb.2023.1322973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/08/2023] [Indexed: 01/23/2024] Open
Abstract
Klebsiella pneumoniae is a World Health Organization priority pathogen and a significant clinical concern for infections of the respiratory and urinary tracts due to widespread and increasing resistance to antimicrobials. In the absence of a vaccine, there is an urgent need to identify novel targets for therapeutic development. Bacterial pathogens, including K. pneumoniae, require the d-block metal ion zinc as an essential micronutrient, which serves as a cofactor for ~6% of the proteome. During infection, zinc acquisition necessitates the use of high affinity uptake systems to overcome niche-specific zinc limitation and host-mediated nutritional immunity. Here, we report the identification of ZnuCBA and ZniCBA, two ATP-binding cassette permeases that are highly conserved in Klebsiella species and contribute to K. pneumoniae AJ218 zinc homeostasis, and the high-resolution structure of the zinc-recruiting solute-binding protein ZniA. The Znu and Zni permeases appear functionally redundant with abrogation of both systems required to reduce K. pneumoniae zinc accumulation. Disruption of both systems also exerted pleiotropic effects on the homeostasis of other d-block elements. Zinc limitation perturbed K. pneumoniae cell morphology and compromised resistance to stressors, such as salt and oxidative stress. The mutant strain lacking both systems showed significantly impaired virulence in acute lung infection models, highlighting the necessity of zinc acquisition in the virulence and pathogenicity of K. pneumoniae.
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Affiliation(s)
- Eve A. Maunders
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Matthew W. Giles
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Katherine Ganio
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Bliss A. Cunningham
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Vicki Bennett-Wood
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Gregory B. Cole
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Dixon Ng
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Christine C. Lai
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Stephanie L. Neville
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Trevor F. Moraes
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Christopher A. McDevitt
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Aimee Tan
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
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8
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Hong Y, Mackenzie ES, Firth SJ, Bolton JRF, Stewart LJ, Waldron KJ, Djoko KY. Mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in Streptococcus pyogenes. Metallomics 2023; 15:mfad064. [PMID: 37849243 PMCID: PMC10644519 DOI: 10.1093/mtomcs/mfad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/16/2023] [Indexed: 10/19/2023]
Abstract
All bacteria possess homeostastic mechanisms that control the availability of micronutrient metals within the cell. Cross-talks between different metal homeostasis pathways within the same bacterial organism have been reported widely. In addition, there have been previous suggestions that some metal uptake transporters can promote adventitious uptake of the wrong metal. This work describes the cross-talk between Cu and the Zn and Mn homeostasis pathways in Group A Streptococcus (GAS). Using a ∆copA mutant strain that lacks the primary Cu efflux pump and thus traps excess Cu in the cytoplasm, we show that growth in the presence of supplemental Cu promotes downregulation of genes that contribute to Zn or Mn uptake. This effect is not associated with changes in cellular Zn or Mn levels. Co-supplementation of the culture medium with Zn or, to a lesser extent, Mn alleviates key Cu stress phenotypes, namely bacterial growth and secretion of the fermentation end-product lactate. However, neither co-supplemental Zn nor Mn influences cellular Cu levels or Cu availability in Cu-stressed cells. In addition, we provide evidence that the Zn or Mn uptake transporters in GAS do not promote Cu uptake. Together, the results from this study strengthen and extend our previous proposal that mis-regulation of Zn and Mn homeostasis is a key phenotype of Cu stress in GAS.
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Affiliation(s)
- YoungJin Hong
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Eilidh S Mackenzie
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Samantha J Firth
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Jack R F Bolton
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Louisa J Stewart
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Kevin J Waldron
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
- Previous affiliation: Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Karrera Y Djoko
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
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9
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Hossain S, Morey JR, Neville SL, Ganio K, Radin JN, Norambuena J, Boyd JM, McDevitt CA, Kehl-Fie TE. Host subversion of bacterial metallophore usage drives copper intoxication. mBio 2023; 14:e0135023. [PMID: 37737591 PMCID: PMC10653882 DOI: 10.1128/mbio.01350-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 08/02/2023] [Indexed: 09/23/2023] Open
Abstract
IMPORTANCE During infection, bacteria must overcome the dual threats of metal starvation and intoxication. This work reveals that the zinc-withholding response of the host sensitizes S. aureus to copper intoxication. In response to zinc starvation, S. aureus utilizes the metallophore staphylopine. The current work revealed that the host can leverage the promiscuity of staphylopine to intoxicate S. aureus during infection. Significantly, staphylopine-like metallophores are produced by a wide range of pathogens, suggesting that this is a conserved weakness that the host can leverage to toxify invaders with copper. Moreover, it challenges the assumption that the broad-spectrum metal binding of metallophores is inherently beneficial to bacteria.
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Affiliation(s)
- Saika Hossain
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Jacqueline R. Morey
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Stephanie L. Neville
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, Australia
| | - Katherine Ganio
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jana N. Radin
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Javiera Norambuena
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, USA
| | - Jeff M. Boyd
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, USA
| | - Christopher A. McDevitt
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, Australia
| | - Thomas E. Kehl-Fie
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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10
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Ray S, Gaudet R. Structures and coordination chemistry of transporters involved in manganese and iron homeostasis. Biochem Soc Trans 2023; 51:897-923. [PMID: 37283482 PMCID: PMC10330786 DOI: 10.1042/bst20210699] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 06/08/2023]
Abstract
A repertoire of transporters plays a crucial role in maintaining homeostasis of biologically essential transition metals, manganese, and iron, thus ensuring cell viability. Elucidating the structure and function of many of these transporters has provided substantial understanding into how these proteins help maintain the optimal cellular concentrations of these metals. In particular, recent high-resolution structures of several transporters bound to different metals enable an examination of how the coordination chemistry of metal ion-protein complexes can help us understand metal selectivity and specificity. In this review, we first provide a comprehensive list of both specific and broad-based transporters that contribute to cellular homeostasis of manganese (Mn2+) and iron (Fe2+ and Fe3+) in bacteria, plants, fungi, and animals. Furthermore, we explore the metal-binding sites of the available high-resolution metal-bound transporter structures (Nramps, ABC transporters, P-type ATPase) and provide a detailed analysis of their coordination spheres (ligands, bond lengths, bond angles, and overall geometry and coordination number). Combining this information with the measured binding affinity of the transporters towards different metals sheds light into the molecular basis of substrate selectivity and transport. Moreover, comparison of the transporters with some metal scavenging and storage proteins, which bind metal with high affinity, reveal how the coordination geometry and affinity trends reflect the biological role of individual proteins involved in the homeostasis of these essential transition metals.
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Affiliation(s)
- Shamayeeta Ray
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, U.S.A
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, U.S.A
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11
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Hossain S, Morey JR, Neville SL, Ganio K, Radin JN, Norambuena J, Boyd JM, McDevitt CA, Kehl-Fie TE. Host subversion of bacterial metallophore usage drives copper intoxication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.30.542972. [PMID: 37398167 PMCID: PMC10312489 DOI: 10.1101/2023.05.30.542972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Microorganisms can acquire metal ions in metal-limited environments using small molecules called metallophores. While metals and their importers are essential, metals can also be toxic, and metallophores have limited ability to discriminate metals. The impact of the metallophore-mediated non-cognate metal uptake on bacterial metal homeostasis and pathogenesis remains to be defined. The globally significant pathogen Staphylococcus aureus uses the Cnt system to secrete the metallophore staphylopine in zinc-limited host niches. Here, we show that staphylopine and the Cnt system facilitate bacterial copper uptake, potentiating the need for copper detoxification. During in vivo infection, staphylopine usage increased S. aureus susceptibility to host-mediated copper stress, indicating that the innate immune response can harness the antimicrobial potential of altered elemental abundances in host niches. Collectively, these observations show that while the broad-spectrum metal-chelating properties of metallophores can be advantageous, the host can exploit these properties to drive metal intoxication and mediate antibacterial control. IMPORTANCE During infection bacteria must overcome the dual threats of metal starvation and intoxication. This work reveals that the zinc-withholding response of the host sensitizes Staphylococcus aureus to copper intoxication. In response to zinc starvation S. aureus utilizes the metallophore staphylopine. The current work revealed that the host can leverage the promiscuity of staphylopine to intoxicate S. aureus during infection. Significantly, staphylopine-like metallophores are produced by a wide range of pathogens, suggesting that this is a conserved weakness that the host can leverage to toxify invaders with copper. Moreover, it challenges the assumption that the broad-spectrum metal binding of metallophores is inherently beneficial to bacteria.
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Affiliation(s)
- Saika Hossain
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jacqueline R Morey
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Stephanie L Neville
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, 3000, Australia
| | - Katherine Ganio
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, 3000, Australia
| | - Jana N Radin
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Javiera Norambuena
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Jeffrey M Boyd
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Christopher A McDevitt
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, 3000, Australia
| | - Thomas E Kehl-Fie
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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12
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Čapek J, Večerek B. Why is manganese so valuable to bacterial pathogens? Front Cell Infect Microbiol 2023; 13:943390. [PMID: 36816586 PMCID: PMC9936198 DOI: 10.3389/fcimb.2023.943390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 01/04/2023] [Indexed: 02/05/2023] Open
Abstract
Apart from oxygenic photosynthesis, the extent of manganese utilization in bacteria varies from species to species and also appears to depend on external conditions. This observation is in striking contrast to iron, which is similar to manganese but essential for the vast majority of bacteria. To adequately explain the role of manganese in pathogens, we first present in this review that the accumulation of molecular oxygen in the Earth's atmosphere was a key event that linked manganese utilization to iron utilization and put pressure on the use of manganese in general. We devote a large part of our contribution to explanation of how molecular oxygen interferes with iron so that it enhances oxidative stress in cells, and how bacteria have learned to control the concentration of free iron in the cytosol. The functioning of iron in the presence of molecular oxygen serves as a springboard for a fundamental understanding of why manganese is so valued by bacterial pathogens. The bulk of this review addresses how manganese can replace iron in enzymes. Redox-active enzymes must cope with the higher redox potential of manganese compared to iron. Therefore, specific manganese-dependent isoenzymes have evolved that either lower the redox potential of the bound metal or use a stronger oxidant. In contrast, redox-inactive enzymes can exchange the metal directly within the individual active site, so no isoenzymes are required. It appears that in the physiological context, only redox-inactive mononuclear or dinuclear enzymes are capable of replacing iron with manganese within the same active site. In both cases, cytosolic conditions play an important role in the selection of the metal used. In conclusion, we summarize both well-characterized and less-studied mechanisms of the tug-of-war for manganese between host and pathogen.
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Affiliation(s)
- Jan Čapek
- *Correspondence: Jan Čapek, ; Branislav Večerek,
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13
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Structure and Function of the Zinc Binding Protein ZrgA from Vibrio cholerae. Int J Mol Sci 2022; 24:ijms24010548. [PMID: 36613986 PMCID: PMC9820375 DOI: 10.3390/ijms24010548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/16/2022] [Accepted: 12/27/2022] [Indexed: 12/30/2022] Open
Abstract
ATP binding cassette (ABC) transporters are the primary means by which bacteria acquire trace elements from the environment. They rely on solute binding proteins (SBPs) to bind the relevant substrate and deliver it to the integral membrane permease for ATP-powered import into the cytoplasm. SBPs of cluster A-I are known to facilitate the transport of essential metals zinc, manganese, and iron, and many have been characterized to date. A group of ABC transporter operons dubbed zinc-regulated genes (zrg) have recently been shown to transport zinc with putative SBPs (zrgA) bearing no homology to the classical cluster A-I family, and a recent crystal structure of a representative protein from Pseudomonas aeruginosa shows no structural similarity to classical SBPs. Thus, the ZrgA proteins appear to represent a newly discovered family of zinc SBPs widespread among Gram-negative bacteria, including human pathogens. Here, we have determined the crystal structure of ZrgA from Vibrio cholerae and characterized its zinc binding in vitro and function in vivo. We also assessed the role of a histidine-rich sequence that appears to be a hallmark of ZrgA proteins that is particularly long in V. cholerae ZrgA. The results show that the zrgA gene is critical to the function of the operon, consistent with a function as an SBP in this system. Further, the His-rich region is not essential to the function of ZrgA, but it does provide additional zinc binding sites in vitro. The structure and zinc binding data for ZrgA reveal interesting differences between it and its homologue from P. aeruginosa, illustrating diversity within this little-studied protein family.
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14
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Ali IAA, Cheung GS, Neelakantan P. Transition Metals and
Enterococcus faecalis
: Homeostasis, Virulence and Perspectives. Mol Oral Microbiol 2022; 37:276-291. [DOI: 10.1111/omi.12391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 09/07/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Islam A. A. Ali
- Department of Endodontics Faculty of Dentistry Mansoura University Mansoura Egypt
| | - Gary S.P. Cheung
- Discipline of Endodontology Division of Restorative Dental Sciences Faculty of Dentistry The University of Hong Kong Hong Kong SAR
| | - Prasanna Neelakantan
- Discipline of Endodontology Division of Restorative Dental Sciences Faculty of Dentistry The University of Hong Kong Hong Kong SAR
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15
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Aggarwal S, Kumaraswami M. Managing Manganese: The Role of Manganese Homeostasis in Streptococcal Pathogenesis. Front Cell Dev Biol 2022; 10:921920. [PMID: 35800897 PMCID: PMC9253540 DOI: 10.3389/fcell.2022.921920] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Pathogenic streptococci require manganese for survival in the host. In response to invading pathogens, the host recruits nutritional immune effectors at infection sites to withhold manganese from the pathogens and control bacterial growth. The manganese scarcity impairs several streptococcal processes including oxidative stress defenses, de novo DNA synthesis, bacterial survival, and virulence. Emerging evidence suggests that pathogens also encounter manganese toxicity during infection and manganese excess impacts streptococcal virulence by manganese mismetallation of non-cognate molecular targets involved in bacterial antioxidant defenses and cell division. To counter host-imposed manganese stress, the streptococcal species employ a sophisticated sensory system that tightly coordinates manganese stress-specific molecular strategies to negate host induced manganese stress and proliferate in the host. Here we review the molecular details of host-streptococcal interactions in the battle for manganese during infection and the significance of streptococcal effectors involved to bacterial pathophysiology.
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Affiliation(s)
- Shifu Aggarwal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Muthiah Kumaraswami
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, United States
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16
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Structural and biochemical characterization of Acinetobacter baumannii ZnuA. J Inorg Biochem 2022; 231:111787. [DOI: 10.1016/j.jinorgbio.2022.111787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/27/2022] [Accepted: 03/06/2022] [Indexed: 11/19/2022]
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17
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Rosen T, Hadley RC, Bozzi AT, Ocampo D, Shearer J, Nolan EM. Zinc sequestration by human calprotectin facilitates manganese binding to the bacterial solute-binding proteins PsaA and MntC. Metallomics 2022; 14:6516941. [PMID: 35090019 PMCID: PMC8908208 DOI: 10.1093/mtomcs/mfac001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/25/2022] [Indexed: 01/30/2023]
Abstract
Zinc is an essential transition metal nutrient for bacterial survival and growth but may become toxic when present at elevated levels. The Gram-positive bacterial pathogen Streptococcus pneumoniae is sensitive to zinc poisoning, which results in growth inhibition and lower resistance to oxidative stress. Streptococcus pneumoniae has a relatively high manganese requirement, and zinc toxicity in this pathogen has been attributed to the coordination of Zn(II) at the Mn(II) site of the solute-binding protein (SBP) PsaA, which prevents Mn(II) uptake by the PsaABC transport system. In this work, we investigate the Zn(II)-binding properties of pneumococcal PsaA and staphylococcal MntC, a related SBP expressed by another Gram-positive bacterial pathogen, Staphylococcus aureus, which contributes to Mn(II) uptake. X-ray absorption spectroscopic studies demonstrate that both SBPs harbor Zn(II) sites best described as five-coordinate, and metal-binding studies in solution show that both SBPs bind Zn(II) reversibly with sub-nanomolar affinities. Moreover, both SBPs exhibit a strong thermodynamic preference for Zn(II) ions, which readily displace bound Mn(II) ions from these proteins. We also evaluate the Zn(II) competition between these SBPs and the human S100 protein calprotectin (CP, S100A8/S100A9 oligomer), an abundant host-defense protein that is involved in the metal-withholding innate immune response. CP can sequester Zn(II) from PsaA and MntC, which facilitates Mn(II) binding to the SBPs. These results demonstrate that CP can inhibit Zn(II) poisoning of the SBPs and provide molecular insight into how S100 proteins may inadvertently benefit bacterial pathogens rather than the host.
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Affiliation(s)
- Tomer Rosen
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue 16-573, Cambridge, MA 02139, USA
| | - Rose C Hadley
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue 16-573, Cambridge, MA 02139, USA
| | - Aaron T Bozzi
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue 16-573, Cambridge, MA 02139, USA
| | - Daniel Ocampo
- Department of Chemistry, Trinity University, San Antonio, TX 78212, USA
| | - Jason Shearer
- Department of Chemistry, Trinity University, San Antonio, TX 78212, USA
| | - Elizabeth M Nolan
- Correspondence: Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue 16-573, Cambridge, MA 02139, USA. Tel: +1-617-452-2495; E-mail:
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