1
|
Peet JJY, Phan AD, Oglesby AG, Nolan EM. Iron Sequestration by Murine Calprotectin Induces Starvation Responses in Pseudomonas aeruginosa. ACS Infect Dis 2024; 10:688-700. [PMID: 38261753 PMCID: PMC11273327 DOI: 10.1021/acsinfecdis.3c00539] [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] [Indexed: 01/25/2024]
Abstract
Pathogen sensing by the mammalian host induces a pro-inflammatory response that involves release of the antimicrobial metal-sequestering protein calprotectin (CP, S100A8/S100A9 heterooligomer, MRP8/MRP14 heterooligomer) from neutrophils. Biochemical investigations on human CP (hCP) have informed the molecular basis of how this protein sequesters metal ions. Murine models of infection have provided invaluable insights into the ability of murine CP (mCP) to compete with bacterial pathogens for essential metal nutrients. Despite this extensive work, our knowledge of how mCP sequesters metals from bacterial pathogens and its impacts on bacterial physiology is limited. Moreover, whether mCP sequesters iron and induces iron-starvation responses in bacterial pathogens has not been evaluated. Here, we examine the ability of mCP to withhold iron from Pseudomonas aeruginosa, a Gram-negative opportunistic pathogen that causes severe infections in immunocompromised individuals and cystic fibrosis patients. We demonstrate that mCP prevents iron uptake and induces iron-starvation responses in P. aeruginosa laboratory strains PA14 and PAO1 and the JSRI-1 clinical isolate from a cystic fibrosis patient. We also show that mCP prevents iron uptake and induces an iron-starvation response in the Gram-positive bacterial pathogen Staphylococcus aureus. The His6 site of mCP is the iron-sequestering site; it exhibits Ca(II)-dependent Fe(II) affinity and binds Fe(II) with subpicomolar affinity in the presence of excess Ca(II) ions. This work is important for understanding the structure, function, and physiological consequences of mCP and how the mammalian host and bacterial pathogens compete for essential metal nutrients.
Collapse
Affiliation(s)
- Janet J. Y. Peet
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Angelica D. Phan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Amanda G. Oglesby
- School of Pharmacy, Department of Pharmaceutical Sciences, University of Maryland, Baltimore, MD, 21201, USA
- School of Medicine, Department of Microbiology and Immunology, University of Maryland, Baltimore, MD, 21021, USA
| | - Elizabeth M. Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| |
Collapse
|
2
|
Killian MM, Brophy MB, Nolan EM, Brunold TC. Spectroscopic and computational investigations of Cobalt(II) binding to the innate immune protein human calprotectin. J Biol Inorg Chem 2024; 29:127-137. [PMID: 38233645 DOI: 10.1007/s00775-023-02034-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: 06/13/2023] [Accepted: 10/30/2023] [Indexed: 01/19/2024]
Abstract
Human calprotectin (CP) is an innate immune protein that participates in the metal-withholding response to infection by sequestering essential metal nutrients from invading microbial pathogens. CP is comprised of S100A8 (α subunit, 10.8 kDa) and S100A9 (β subunit, 13.2 kDa). Two transition-metal binding sites of CP form at the S100A8/S100A9 dimer interface. Site 1 is a His3Asp motif comprised of His83 and His87 from the S100A8 subunit and His20 and Asp30 from the S100A9 subunit. Site 2 is an unusual hexahistidine motif composed of S100A8 residues His17 and His27 and S100A9 residues His91, His95, His103, and His105. In the present study, the His3Asp and His6 sites of CP were further characterized by utilizing Co2+ as a spectroscopic probe. Magnetic circular dichroism spectroscopy was employed in conjunction with electron paramagnetic resonance spectroscopy and density functional theory computations to characterize the Co2+-bound S100A8(C42S)/S100A9(C3S) CP-Ser variant and six site variants that allowed the His3Asp and His6 sites to be further probed. Our results provide new insight into the metal-binding sites of CP-Ser and the effect of amino acid substitutions on the structure of site 2.
Collapse
Affiliation(s)
- Michelle M Killian
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Megan B Brophy
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
| | - Thomas C Brunold
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
| |
Collapse
|
3
|
Wang Q, Long G, Luo H, Zhu X, Han Y, Shang Y, Zhang D, Gong R. S100A8/A9: An emerging player in sepsis and sepsis-induced organ injury. Biomed Pharmacother 2023; 168:115674. [PMID: 37812889 DOI: 10.1016/j.biopha.2023.115674] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/04/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023] Open
Abstract
Sepsis, the foremost contributor to mortality in intensive care unit patients, arises from an uncontrolled systemic response to invading infections, resulting in extensive harm across multiple organs and systems. Recently, S100A8/A9 has emerged as a promising biomarker for sepsis and sepsis-induced organ injury, and targeting S100A8/A9 appeared to ameliorate inflammation-induced tissue damage and improve adverse outcomes. S100A8/A9, a calcium-binding heterodimer mainly found in neutrophils and monocytes, serves as a causative molecule with pro-inflammatory and immunosuppressive properties, which are vital in the pathogenesis of sepsis. Therefore, improving our comprehension of how S100A8/A9 acts as a pathological player in the development of sepsis is imperative for advancing research on sepsis. Our review is the first-to the best of our knowledge-to discuss the biology of S100A8/A9 and its release mechanisms, summarize recent advances concerning the vital roles of S100A8/A9 in sepsis and the consequential organ damage, and underscore its potential as a promising diagnostic biomarker and therapeutic target for sepsis.
Collapse
Affiliation(s)
- Qian Wang
- Wuhan Jinyintan Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan 430023, China
| | - Gangyu Long
- Wuhan Jinyintan Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan 430023, China
| | - Hong Luo
- Wuhan Jinyintan Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan 430023, China
| | - Xiqun Zhu
- Hubei Cancer Hospital, Tongji Medical College, HUST, Wuhan 430079, China
| | - Yang Han
- Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan 430023, China
| | - You Shang
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, HUST, Wuhan 430030, China.
| | - Dingyu Zhang
- Wuhan Jinyintan Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan 430023, China; Hubei Clinical Research Center for Infectious Diseases, Wuhan 430023, China; Wuhan Research Center for Communicable Disease Diagnosis and Treatment, Chinese Academy of Medical Sciences, Wuhan 430023, China; Joint Laboratory of Infectious Diseases and Health, Wuhan Institute of Virology and Wuhan Jinyintan Hospital, Chinese Academy of Sciences, Wuhan 430023, China.
| | - Rui Gong
- The First Affiliated Hospital of University of Science and Technology of China (USTC), Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, China.
| |
Collapse
|
4
|
Ribeiro CMP, Higgs MG, Muhlebach MS, Wolfgang MC, Borgatti M, Lampronti I, Cabrini G. Revisiting Host-Pathogen Interactions in Cystic Fibrosis Lungs in the Era of CFTR Modulators. Int J Mol Sci 2023; 24:ijms24055010. [PMID: 36902441 PMCID: PMC10003689 DOI: 10.3390/ijms24055010] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/25/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) modulators, a new series of therapeutics that correct and potentiate some classes of mutations of the CFTR, have provided a great therapeutic advantage to people with cystic fibrosis (pwCF). The main hindrances of the present CFTR modulators are related to their limitations in reducing chronic lung bacterial infection and inflammation, the main causes of pulmonary tissue damage and progressive respiratory insufficiency, particularly in adults with CF. Here, the most debated issues of the pulmonary bacterial infection and inflammatory processes in pwCF are revisited. Special attention is given to the mechanisms favoring the bacterial infection of pwCF, the progressive adaptation of Pseudomonas aeruginosa and its interplay with Staphylococcus aureus, the cross-talk among bacteria, the bronchial epithelial cells and the phagocytes of the host immune defenses. The most recent findings of the effect of CFTR modulators on bacterial infection and the inflammatory process are also presented to provide critical hints towards the identification of relevant therapeutic targets to overcome the respiratory pathology of pwCF.
Collapse
Affiliation(s)
- Carla M. P. Ribeiro
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Correspondence: (C.M.P.R.); (G.C.)
| | - Matthew G. Higgs
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marianne S. Muhlebach
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Pediatrics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Matthew C. Wolfgang
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Monica Borgatti
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
| | - Ilaria Lampronti
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
| | - Giulio Cabrini
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: (C.M.P.R.); (G.C.)
| |
Collapse
|
5
|
Post-translational modifications on the metal-sequestering protein calprotectin. Biometals 2023:10.1007/s10534-023-00493-x. [PMID: 36826733 PMCID: PMC10393864 DOI: 10.1007/s10534-023-00493-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/19/2023] [Indexed: 02/25/2023]
Abstract
Human calprotectin (CP, S100A8/S100A9 oligomer) is an abundant neutrophil protein that contributes to innate immunity by sequestering nutrient metal ions in the extracellular space. This process starves invading microbial pathogens of essential metal nutrients, which can inhibit growth and colonization. Over the past decade, fundamental and clinical studies have revealed that the S100A8 and S100A9 subunits of CP exhibit a variety of post-translational modifications (PTMs). This review summarizes PTMs on the CP subunits that have been detected and highlights two recent studies that evaluated the structural and functional consequences of methionine and cysteine oxidation on CP. Collectively, these investigations indicate that the molecular speciation of extracellular CP is complex and composed of multiple proteoforms. Moreover, PTMs may impact biological function and the lifetime of the protein. It is therefore important that post-translationally modified CP species receive consideration and integration into the current working model for how CP functions in nutritional immunity.
Collapse
|
6
|
Polakowska M, Steczkiewicz K, Szczepanowski RH, Wysłouch-Cieszyńska A. Toward an understanding of the conformational plasticity of S100A8 and S100A9 Ca 2+-binding proteins. J Biol Chem 2023; 299:102952. [PMID: 36731796 PMCID: PMC10124908 DOI: 10.1016/j.jbc.2023.102952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 01/16/2023] [Accepted: 01/25/2023] [Indexed: 02/01/2023] Open
Abstract
S100A8 and S100A9 are small, human, Ca2+-binding proteins with multiple intracellular and extracellular functions in signaling, regulation, and defense. The two proteins are not detected as monomers but form various noncovalent homo- or hetero-oligomers related to specific activities in human physiology. Because of their significant roles in numerous medical conditions, there has been intense research on the conformational properties of various S100A8 and S100A9 proteoforms as essential targets of drug discovery. NMR or crystal structures are currently available only for mutated or truncated protein complexes, mainly with bound metal ions, that may well reflect the proteins' properties outside cells but not in other biological contexts in which they perform. Here, we used structural mass spectrometry methods combined with molecular dynamics simulations to compare the conformations of wild-type full-length S100A8 and S100A9 subunits in biologically relevant homo- and hetero-dimers and in higher oligomers formed in the presence of calcium or zinc ions. We provide, first, rationales for their functional response to changing environmental conditions, by elucidating differences between proteoforms in flexible protein regions that may provide the plasticity of the binding sites for the multiple targets, and second, the key factors contributing to the variable stability of the oligomers. The described methods and a systematic view of the conformational properties of S100A8 and S100A9 complexes provide a basis for further research to characterize and modulate their functions for basic science and therapies.
Collapse
Affiliation(s)
- Magdalena Polakowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Kamil Steczkiewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Roman H Szczepanowski
- International Institute of Molecular and Cell Biology, Księcia Trojdena Street, 02-109 Warsaw, Poland
| | | |
Collapse
|
7
|
New Faecal Calprotectin Assay by IDS: Validation and Comparison to DiaSorin Method. Diagnostics (Basel) 2022; 12:diagnostics12102338. [PMID: 36292026 PMCID: PMC9600005 DOI: 10.3390/diagnostics12102338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Background: The faecal calprotectin (FC) measurement is used for inflammatory bowel disease (IBD) diagnosis and follow-up. The aim of this study was to validate for the first time the new IDS FC extraction device and immunoassay kit, and to compare it with the DiaSorin test in patients with and without IBD. Methods: First, the precision of the IDS assay and its stability were assessed. Then, 379 stool extracts were analysed with the IDS kit on iSYS and compared with a DiaSorin Liaison XL assay. Results: The intra- and inter-assay CVs did not exceed 5%. The stool samples were stable up to 4 weeks at −20 °C. Lot-to-lot comparison showed a good correlation (Lot1 = 1.06 × Lot2 + 0.60; p > 0.05). The Passing and Bablok regression showed no significant deviation from linearity between the two methods (IDS = 1.06 × DiaSorin − 0.6; p > 0.05; concordance correlation coefficient = 0.93). According to the recommended cut-offs, the IDS assay identified more IBD and irritable bowel syndrome patients than DiaSorin, which had more borderline results (16 vs. 20%, respectively). Conclusions: The IDS faecal calprotectin had good analytical validation parameters. Compared to the DiaSorin method, it showed comparable results, but slightly outperformed it in the identification of more IBD patients and active disease.
Collapse
|
8
|
Johnstone KF, Herzberg MC. Antimicrobial peptides: Defending the mucosal epithelial barrier. FRONTIERS IN ORAL HEALTH 2022; 3:958480. [PMID: 35979535 PMCID: PMC9376388 DOI: 10.3389/froh.2022.958480] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/30/2022] [Indexed: 11/13/2022] Open
Abstract
The recent epidemic caused by aerosolized SARS-CoV-2 virus illustrates the importance and vulnerability of the mucosal epithelial barrier against infection. Antimicrobial proteins and peptides (AMPs) are key to the epithelial barrier, providing immunity against microbes. In primitive life forms, AMPs protect the integument and the gut against pathogenic microbes. AMPs have also evolved in humans and other mammals to enhance newer, complex innate and adaptive immunity to favor the persistence of commensals over pathogenic microbes. The canonical AMPs are helictical peptides that form lethal pores in microbial membranes. In higher life forms, this type of AMP is exemplified by the defensin family of AMPs. In epithelial tissues, defensins, and calprotectin (complex of S100A8 and S100A9) have evolved to work cooperatively. The mechanisms of action differ. Unlike defensins, calprotectin sequesters essential trace metals from microbes, which inhibits growth. This review focuses on defensins and calprotectin as AMPs that appear to work cooperatively to fortify the epithelial barrier against infection. The antimicrobial spectrum is broad with overlap between the two AMPs. In mice, experimental models highlight the contribution of both AMPs to candidiasis as a fungal infection and periodontitis resulting from bacterial dysbiosis. These AMPs appear to contribute to innate immunity in humans, protecting the commensal microflora and restricting the emergence of pathobionts and pathogens. A striking example in human innate immunity is that elevated serum calprotectin protects against neonatal sepsis. Calprotectin is also remarkable because of functional differences when localized in epithelial and neutrophil cytoplasm or released into the extracellular environment. In the cytoplasm, calprotectin appears to protect against invasive pathogens. Extracellularly, calprotectin can engage pathogen-recognition receptors to activate innate immune and proinflammatory mechanisms. In inflamed epithelial and other tissue spaces, calprotectin, DNA, and histones are released from degranulated neutrophils to form insoluble antimicrobial barriers termed neutrophil extracellular traps. Hence, calprotectin and other AMPs use several strategies to provide microbial control and stimulate innate immunity.
Collapse
Affiliation(s)
| | - Mark C. Herzberg
- Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN, United States
| |
Collapse
|
9
|
Zhou C, Ji C, Nie Y, Yang J, Zhao J. Poly(ethylene oxide) Is Positively Charged in Aqueous Solutions. Gels 2022; 8:gels8040213. [PMID: 35448114 PMCID: PMC9029200 DOI: 10.3390/gels8040213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/23/2022] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
There have been controversies about the binding of cations to poly(ethylene oxide) (PEO) chains in aqueous solutions. In the current study, single molecular evidence of charging PEO chains by cation binding in aqueous solutions is provided. From the adoption of the photon-counting histogram method, it is discovered that the local pH value at the vicinity of the PEO chain is higher than the bulk solution, showing that the PEO chain is positively charged. Such a situation exists with and without the presence of salt (NaCl) in the solution, presumably due to the binding of cations, such as hydronium and sodium ions. Single molecular electrophoresis experiments using fluorescence correlation spectroscopy demonstrate that the PEO chains are weakly charged with a charging extent of ~5%. In comparison to the salt-free condition, the addition of external salt (NaCl) at moderate concentrations further charges the chain. The charging causes the PEO chains to expand and a further increase in the salt concentration causes the chain to shrink, exhibiting a polyelectrolyte-like behavior, demonstrated by the hydrodynamic radii of a single PEO chain. The effect of ion identity is discovered with alkali cations, with the order of the charging capacity of Li+ < Na+ < Cs+ < K+.
Collapse
Affiliation(s)
- Chao Zhou
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunda Ji
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuchen Nie
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence:
| |
Collapse
|
10
|
Lin Y, Gross ML. Mass Spectrometry-Based Structural Proteomics for Metal Ion/Protein Binding Studies. Biomolecules 2022; 12:135. [PMID: 35053283 PMCID: PMC8773722 DOI: 10.3390/biom12010135] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/13/2022] [Accepted: 01/13/2022] [Indexed: 01/01/2023] Open
Abstract
Metal ions are critical for the biological and physiological functions of many proteins. Mass spectrometry (MS)-based structural proteomics is an ever-growing field that has been adopted to study protein and metal ion interactions. Native MS offers information on metal binding and its stoichiometry. Footprinting approaches coupled with MS, including hydrogen/deuterium exchange (HDX), "fast photochemical oxidation of proteins" (FPOP) and targeted amino-acid labeling, identify binding sites and regions undergoing conformational changes. MS-based titration methods, including "protein-ligand interactions by mass spectrometry, titration and HD exchange" (PLIMSTEX) and "ligand titration, fast photochemical oxidation of proteins and mass spectrometry" (LITPOMS), afford binding stoichiometry, binding affinity, and binding order. These MS-based structural proteomics approaches, their applications to answer questions regarding metal ion protein interactions, their limitations, and recent and potential improvements are discussed here. This review serves as a demonstration of the capabilities of these tools and as an introduction to wider applications to solve other questions.
Collapse
Affiliation(s)
- Yanchun Lin
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
| |
Collapse
|
11
|
Silvers R, Stephan JR, Griffin RG, Nolan EM. Molecular Basis of Ca(II)-Induced Tetramerization and Transition-Metal Sequestration in Human Calprotectin. J Am Chem Soc 2021; 143:18073-18090. [PMID: 34699194 PMCID: PMC8643164 DOI: 10.1021/jacs.1c06402] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Human calprotectin (CP, S100A8/S100A9 oligomer, MRP8/MRP14 oligomer) is an abundant innate immune protein that contributes to the host metal-withholding response. Its ability to sequester transition metal nutrients from microbial pathogens depends on a complex interplay of Ca(II) binding and self-association, which converts the αβ heterodimeric apo protein into a Ca(II)-bound (αβ)2 heterotetramer that displays enhanced transition metal affinities, antimicrobial activity, and protease stability. A paucity of structural data on the αβ heterodimer has hampered molecular understanding of how Ca(II) binding enables CP to exert its metal-sequestering innate immune function. We report solution NMR data that reveal how Ca(II) binding affects the structure and dynamics of the CP αβ heterodimer. These studies provide a structural model in which the apo αβ heterodimer undergoes conformational exchange and switches between two states, a tetramerization-incompetent or "inactive" state and a tetramerization-competent or "active" state. Ca(II) binding to the EF-hands of the αβ heterodimer causes the active state to predominate, resulting in self-association and formation of the (αβ)2 heterotetramer. Moreover, Ca(II) binding causes local and allosteric ordering of the His3Asp and His6 metal-binding sites. Ca(II) binding to the noncanonical EF-hand of S100A9 positions (A9)D30 and organizes the His3Asp site. Remarkably, Ca(II) binding causes allosteric effects in the C-terminal region of helix αIV of S100A9, which stabilize the α-helicity at positions H91 and H95 and thereby organize the functionally versatile His6 site. Collectively, this study illuminates the molecular basis for how CP responds to high extracellular Ca(II) concentrations, which enables its metal-sequestering host-defense function.
Collapse
Affiliation(s)
- Robert Silvers
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, FL 32306, USA
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
| | - Jules R. Stephan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Robert G. Griffin
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elizabeth M. Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| |
Collapse
|
12
|
Antelo GT, Vila AJ, Giedroc DP, Capdevila DA. Molecular Evolution of Transition Metal Bioavailability at the Host-Pathogen Interface. Trends Microbiol 2021; 29:441-457. [PMID: 32951986 PMCID: PMC7969482 DOI: 10.1016/j.tim.2020.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/01/2020] [Accepted: 08/19/2020] [Indexed: 12/21/2022]
Abstract
The molecular evolution of the adaptive response at the host-pathogen interface has been frequently referred to as an 'arms race' between the host and bacterial pathogens. The innate immune system employs multiple strategies to starve microbes of metals. Pathogens, in turn, develop successful strategies to maintain access to bioavailable metal ions under conditions of extreme restriction of transition metals, or nutritional immunity. However, the processes by which evolution repurposes or re-engineers host and pathogen proteins to perform or refine new functions have been explored only recently. Here we review the molecular evolution of several human metalloproteins charged with restricting bacterial access to transition metals. These include the transition metal-chelating S100 proteins, natural resistance-associated macrophage protein-1 (NRAMP-1), transferrin, lactoferrin, and heme-binding proteins. We examine their coevolution with bacterial transition metal acquisition systems, involving siderophores and membrane-spanning metal importers, and the biological specificity of allosteric transcriptional regulatory proteins tasked with maintaining bacterial metallostasis. We also discuss the evolution of metallo-β-lactamases; this illustrates how rapid antibiotic-mediated evolution of a zinc metalloenzyme obligatorily occurs in the context of host-imposed nutritional immunity.
Collapse
Affiliation(s)
- Giuliano T Antelo
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), C1405BWE Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Alejandro J Vila
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET-UNR), Ocampo and Esmeralda, S2002LRK Rosario, Argentina; Área Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, S2002LRK Rosario, Argentina
| | - David P Giedroc
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA; Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA.
| | - Daiana A Capdevila
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), C1405BWE Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina.
| |
Collapse
|