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Chivers PT, Basak P, Maroney MJ. One His, two His…the emerging roles of histidine in cellular nickel trafficking. J Inorg Biochem 2024; 259:112668. [PMID: 39053077 DOI: 10.1016/j.jinorgbio.2024.112668] [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: 04/29/2024] [Revised: 07/15/2024] [Accepted: 07/16/2024] [Indexed: 07/27/2024]
Abstract
Biological environments present a complex array of metal-binding ligands. Metal-binding proteins have been the overwhelming focus of study because of their important and well-defined biological roles. Consequently, the presence of functional low molecular weight (LMW) metal-ligand complexes has been overlooked in terms of their roles in metallobiochemistry, particularly within cells. Recent studies in microbial systems have illuminated the different roles of L-histidine in nickel uptake, gene expression, and metalloenzyme maturation. In this focused critical review, these roles are surveyed in the context of the coordination chemistry of Ni(II) ions and the amino acid histidine, and the physico-chemical properties of nickel complexes of histidine. These complexes are fundamentally important to cellular metal homeostasis and further work is needed to fully define their contributions.
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Affiliation(s)
- Peter T Chivers
- Departments of Biosciences and Chemistry, University of Durham, Durham DH1 3LE, UK
| | - Priyanka Basak
- Department of Chemistry, University of Massachusetts, Amherst, MA 01002, United States of America
| | - Michael J Maroney
- Department of Chemistry, University of Massachusetts, Amherst, MA 01002, United States of America.
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2
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Arioli S, Mangieri N, Zanchetta Y, Russo P, Mora D. Substitution of Asp29 with Asn29 in the metallochaperone UreE of Streptococcus thermophilus DSM 20617 T increases the urease activity and anticipates urea hydrolysis during milk fermentation. Int J Food Microbiol 2024; 416:110684. [PMID: 38513545 DOI: 10.1016/j.ijfoodmicro.2024.110684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 03/23/2024]
Abstract
Urease operon is highly conserved within the species Streptococcus thermophilus and urease-negative strains are rare in nature. S. thermophilus MIMO1, isolated from commercial yogurt, was previously characterized as urease-positive Ni-dependent strain. Beside a mutation in ureQ, coding for a nickel ABC transporter permease, the strain MIMO1 showed a mutation in ureE gene which code for a metallochaperone involved in Ni delivery to the urease catalytic site. The single base mutation in ureE determined a substitution of Asp29 with Asn29 in the metallochaperone in a conserved protein region not involved in the catalytic activity. With the aim to investigate the role Asp29vs Asn29 substitution in UreE on the urease activity of S. thermophilus, ureE gene of the reference strain DSM 20617T (ureEDSM20617) was replaced by ureE gene of strain MIMO1 (ureEMIMO1) to obtain the recombinant ES3. In-gel detection of urease activity revealed that the substitution of Asp29 with Asn29 in UreE resulted in a higher stability of the enzyme complexes. Moreover, the recombinant ES3 showed higher level of urease activity compared to the wildtype without any detectable increase in the expression level of ureC gene, thus highlighting the role of UreE not only in Ni assembly but also on the level of urease activity. During the growth in milk, the recombinant ES3 showed an anticipated urease activity compared to the wildtype, and analogous milk fermentation performance. The overall data obtained by comparing urease-positive and urease-negative strains/mutants confirmed that urease activity strongly impacts on the milk fermentation process and specifically on the yield of the homolactic fermentation.
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Affiliation(s)
- Stefania Arioli
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Nicola Mangieri
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Ylenia Zanchetta
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Pasquale Russo
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Diego Mora
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy.
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3
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Zambelli B, Basak P, Hu H, Piccioli M, Musiani F, Broll V, Imbert L, Boisbouvier J, Maroney MJ, Ciurli S. The structure of the high-affinity nickel-binding site in the Ni,Zn-HypA•UreE2 complex. Metallomics 2023; 15:mfad003. [PMID: 36638839 PMCID: PMC10001889 DOI: 10.1093/mtomcs/mfad003] [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: 09/15/2022] [Accepted: 01/11/2023] [Indexed: 01/15/2023]
Abstract
The maturation pathway for the nickel-dependent enzyme urease utilizes the protein UreE as a metallochaperone to supply Ni(II) ions. In Helicobacter pylori urease maturation also requires HypA and HypB, accessory proteins that are commonly associated with hydrogenase maturation. Herein we report on the characterization of a protein complex formed between HypA and the UreE2 dimer. Nuclear magnetic resonance (NMR) coupled with molecular modelling show that the protein complex apo, Zn-HypA•UreE2, forms between the rigorously conserved Met-His-Glu (MHE motif) Ni-binding N-terminal sequence of HypA and the two conserved His102A and His102B located at the dimer interface of UreE2. This complex forms in the absence of Ni(II) and is supported by extensive protein contacts that include the use of the C-terminal sequences of UreE2 to form additional strands of β-sheet with the Ni-binding domain of HypA. The Ni-binding properties of apo, Zn-HypA•UreE2 and the component proteins were investigated by isothermal titration calorimetry using a global fitting strategy that included all of the relevant equilibria, and show that the Ni,Zn-HypA•UreE2 complex contains a single Ni(II)-binding site with a sub-nanomolar KD. The structural features of this novel Ni(II) site were elucidated using proteins produced with specifically deuterated amino acids, protein point mutations, and the analyses of X-ray absorption spectroscopy, hyperfine shifted NMR features, as well as molecular modeling coupled with quantum-mechanical calculations. The results show that the complex contains a six-coordinate, high-spin Ni(II) site with ligands provided by both component proteins.
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Affiliation(s)
- Barbara Zambelli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Priyanka Basak
- Department of Chemistry and Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, MA, USA
| | - Heidi Hu
- Department of Chemistry and Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, MA, USA
| | - Mario Piccioli
- Centre for Magnetic Resonance, Department of Chemistry, University of Florence, Florence Italy
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Valquiria Broll
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Lionel Imbert
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Grenoble, France
| | - Jerome Boisbouvier
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Grenoble, France
| | - Michael J Maroney
- Department of Chemistry and Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, MA, USA
| | - Stefano Ciurli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
- Centre for Magnetic Resonance, Department of Chemistry, University of Florence, Florence Italy
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Xia X. Multiple regulatory mechanisms for pH homeostasis in the gastric pathogen, Helicobacter pylori. ADVANCES IN GENETICS 2022; 109:39-69. [PMID: 36334916 DOI: 10.1016/bs.adgen.2022.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Acid-resistance in gastric pathogen Helicobacter pylori requires the coordination of four essential processes to regulate urease activity. Firstly, urease expression above a base level needs to be finely tuned at different ambient pH. Secondly, as nickel is needed to activate urease, nickel homeostasis needs to be maintained by proteins that import and export nickel ions, and sequester, store and release nickel when needed. Thirdly, urease accessary proteins that activate urease activity by nickel insertion need to be expressed. Finally, a reliable source of urea needs to be maintained by both intrinsic and extrinsic sources of urea. Two-component systems (arsRS and flgRS), as well as a nickel response regulator (NikR), sense the change in pH and act on a variety of genes to accomplish the function of acid resistance without causing cellular overalkalization and nickel toxicity. Nickel storage proteins also feature built-in switches to store nickel at neutral pH and release nickel at low pH. This review summarizes the current status of H. pylori research and highlights a number of hypotheses that need to be tested.
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Affiliation(s)
- Xuhua Xia
- Department of Biology, University of Ottawa, Ottawa, Canada; Ottawa Institute of Systems Biology, Ottawa, Canada.
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5
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Kumar S, Vinella D, De Reuse H. Nickel, an essential virulence determinant of Helicobacter pylori: Transport and trafficking pathways and their targeting by bismuth. Adv Microb Physiol 2022; 80:1-33. [PMID: 35489790 DOI: 10.1016/bs.ampbs.2022.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Metal acquisition and intracellular trafficking are crucial for all cells and metal ions have been recognized as virulence determinants in bacterial pathogens. Nickel is required for the pathogenicity of H. pylori. This bacterial pathogen colonizes the stomach of about half of the human population worldwide and is associated with gastric cancer that is responsible for 800,000 deaths per year. H. pylori possesses two nickel-enzymes that are essential for in vivo colonization, a [NiFe] hydrogenase and an abundant urease responsible for resistance to gastric acidity. Because of these two enzymes, survival of H. pylori relies on an important supply of nickel, implying tight control strategies to avoid its toxic accumulation or deprivation. H. pylori possesses original mechanisms for nickel uptake, distribution, storage and trafficking that will be discussed in this review. During evolution, acquisition of nickel transporters and specific nickel-binding proteins has been a decisive event to allow Helicobacter species to become able to colonize the stomach. Accordingly, many of the factors involved in these mechanisms are required for mouse colonization by H. pylori. These mechanisms are controlled at different levels including protein interaction networks, transcriptional, post-transcriptional and post-translational regulation. Bismuth is another metal used in combination with antibiotics to efficiently treat H. pylori infections. Although the precise mode of action of bismuth is unknown, many targets have been identified in H. pylori and there is growing evidence that bismuth interferes with the essential nickel pathways. Understanding the metal pathways will help improve treatments against H. pylori and other pathogens.
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Affiliation(s)
- Sumith Kumar
- Unité Pathogenèse de Helicobacter, CNRS UMR6047, Département de Microbiologie, Institut Pasteur, Paris, France
| | - Daniel Vinella
- Unité Pathogenèse de Helicobacter, CNRS UMR6047, Département de Microbiologie, Institut Pasteur, Paris, France
| | - Hilde De Reuse
- Unité Pathogenèse de Helicobacter, CNRS UMR6047, Département de Microbiologie, Institut Pasteur, Paris, France.
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Abstract
Hydrogenases and ureases play vital metabolic functions in all three domains of life. However, nickel ions are cytotoxic because they can inactivate enzymes that require less competitive ions (e.g. Mg2+) in the Irving-Williams series to function. Life has evolved elegant mechanisms to solve the problem of delivering the toxic metal to the active site of nickel-containing enzymes inside the cells. Here, we review our current understanding of nickel trafficking along the hydrogenase and urease maturation pathways. Metallochaperones and accessory proteins (SlyD, HypA, HypB, UreD, UreE, UreF, and UreG) form specific protein complexes to allow the transfer of nickel from one protein to another without releasing the toxic metal into the cytoplasm. The role of SlyD is not fully understood, but it can interact with and transfer its nickel to HypB. In the hydrogenase maturation pathway, nickel is transferred from HypB to HypA, which can then deliver its nickel to the hydrogenase large subunit precursor. In Helicobacter pylori, the urease maturation pathway receives its nickel from HypA of the hydrogenase maturation pathway via the formation of a HypA/UreE2 complex. Guanosine triphosphate (GTP) binding promotes the formation of a UreE2G2 complex, where UreG receives a nickel from UreE. In the final step of the urease maturation, nickel/GTP-bound UreG forms an activation complex with UreF, UreD, and apo-urease. Upon GTP hydrolysis, nickel is released from UreG to the urease. Finally, some common themes learned from the hydrogenase-urease maturation pathway are discussed.
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Affiliation(s)
- Ka Lung Tsang
- School of Life Sciences, Centre for Protein Science and Crystallography, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Kam-Bo Wong
- School of Life Sciences, Centre for Protein Science and Crystallography, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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Nickel as a virulence factor in the Class I bacterial carcinogen, Helicobacter pylori. Semin Cancer Biol 2021; 76:143-155. [PMID: 33865991 DOI: 10.1016/j.semcancer.2021.04.009] [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: 03/19/2021] [Accepted: 04/12/2021] [Indexed: 01/16/2023]
Abstract
Helicobacter pylori is a human bacterial pathogen that causes peptic ulcers and has been designated a Class I carcinogen by the International Agency for Research on Cancer (IARC). Its ability to survive in the acid environment of the stomach, to colonize the stomach mucosa, and to cause cancer, are linked to two enzymes that require nickel-urease and hydrogenase. Thus, nickel is an important virulence factor and the proteins involved in nickel trafficking are potential antibiotic targets. This review summarizes the nickel biochemistry of H. pylori with a focus on the roles of nickel in virulence, nickel homeostasis, maturation of urease and hydrogenase, and the unique nickel trafficking that occurs between the hydrogenase maturation pathway and urease nickel incorporation that is mediated by the metallochaperone HypA and its partner, HypB.
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8
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Chatterjee S, Kumari S, Rath S, Priyadarshanee M, Das S. Diversity, structure and regulation of microbial metallothionein: metal resistance and possible applications in sequestration of toxic metals. Metallomics 2020; 12:1637-1655. [PMID: 32996528 DOI: 10.1039/d0mt00140f] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metallothioneins (MTs) are a group of cysteine-rich, universal, low molecular weight proteins distributed widely in almost all major taxonomic groups ranging from tiny microbes to highly organized vertebrates. The primary function of this protein is storage, transportation and binding of metals, which enable microorganisms to detoxify heavy metals. In the microbial world, these peptides were first identified in a cyanobacterium Synechococcus as the SmtA protein which exhibits high affinity towards rising level of zinc and cadmium to preserve metal homeostasis in a cell. In yeast, MTs aid in reserving copper and confer protection against copper toxicity by chelating excess copper ions in a cell. Two MTs, CUP1 and Crs5, originating from Saccharomyces cerevisiae predominantly bind to copper though are capable of binding with zinc and cadmium ions. MT superfamily 7 is found in ciliated protozoa which show high affinity towards copper and cadmium. Several tools and techniques, such as western blot, capillary electrophoresis, inductively coupled plasma, atomic emission spectroscopy and high performance liquid chromatography, have been extensively utilized for the detection and quantification of microbial MTs which are utilized for the efficient remediation and sequestration of heavy metals from a contaminated environment.
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Affiliation(s)
- Shreosi Chatterjee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India.
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9
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Abstract
Nickel is essential for the survival of many pathogenic bacteria. E. coli and H. pylori require nickel for [NiFe]-hydrogenases. H. pylori also requires nickel for urease. At high concentrations nickel can be toxic to the cell, therefore, nickel concentrations are tightly regulated. Metalloregulators help to maintain nickel concentration in the cell by regulating the expression of the genes associated with nickel import and export. Nickel import into the cell, delivery of nickel to target proteins, and export of nickel from the cell is a very intricate and well-choreographed process. The delivery of nickel to [NiFe]-hydrogenase and urease is complex and involves several chaperones and accessory proteins. A combination of biochemical, crystallographic, and spectroscopic techniques has been utilized to study the structures of these proteins, as well as protein-protein interactions resulting in an expansion of our knowledge regarding how these proteins sense and bind nickel. In this review, recent advances in the field will be discussed, focusing on the metal site structures of nickel bound to metalloregulators and chaperones.
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10
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Abstract
Maturation of urease involves post-translational insertion of nickel ions to form an active site with a carbamylated lysine ligand and is assisted by urease accessory proteins UreD, UreE, UreF and UreG. Here, we review our current understandings on how these urease accessory proteins facilitate the urease maturation. The urease maturation pathway involves the transfer of Ni2+ from UreE → UreG → UreF/UreD → urease. To avoid the release of the toxic metal to the cytoplasm, Ni2+ is transferred from one urease accessory protein to another through specific protein–protein interactions. One central theme depicts the role of guanosine triphosphate (GTP) binding/hydrolysis in regulating the binding/release of nickel ions and the formation of the protein complexes. The urease and [NiFe]-hydrogenase maturation pathways cross-talk with each other as UreE receives Ni2+ from hydrogenase maturation factor HypA. Finally, the druggability of the urease maturation pathway is reviewed.
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11
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Lacasse MJ, Summers KL, Khorasani-Motlagh M, George GN, Zamble DB. Bimodal Nickel-Binding Site on Escherichia coli [NiFe]-Hydrogenase Metallochaperone HypA. Inorg Chem 2019; 58:13604-13618. [PMID: 31273981 DOI: 10.1021/acs.inorgchem.9b00897] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
[NiFe]-hydrogenase enzymes catalyze the reversible oxidation of hydrogen at a bimetallic cluster and are used by bacteria and archaea for anaerobic growth and pathogenesis. Maturation of the [NiFe]-hydrogenase requires several accessory proteins to assemble and insert the components of the active site. The penultimate maturation step is the delivery of nickel to a primed hydrogenase enzyme precursor protein, a process that is accomplished by two nickel metallochaperones, the accessory protein HypA and the GTPase HypB. Recent work demonstrated that nickel is rapidly transferred to HypA from GDP-loaded HypB within the context of a protein complex in a nickel selective and unidirectional process. To investigate the mechanism of metal transfer, we examined the allosteric effects of nucleotide cofactors and partner proteins on the nickel environments of HypA and HypB by using a combination of biochemical, microbiological, computational, and spectroscopic techniques. We observed that loading HypB with either GDP or a nonhydrolyzable GTP analogue resulted in a similar nickel environment. In addition, interaction with a mutant version of HypA with disrupted nickel binding, H2Q-HypA, does not induce substantial changes to the HypB G-domain nickel site. Instead, the results demonstrate that HypB modifies the acceptor site of HypA. Analysis of a peptide maquette derived from the N-terminus of HypA revealed that nickel is predominately coordinated by atoms from the N-terminal Met-His motif. Furthermore, HypA is capable of two nickel-binding modes at the N-terminus, a HypB-induced mode and a binding mode that mirrors the peptide maquette. Collectively, these results reveal that HypB brings about changes in the nickel coordination of HypA, providing a mechanism for the HypB-dependent control of the acquisition and release of nickel by HypA.
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Affiliation(s)
- Michael J Lacasse
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S 3H6 , Canada
| | - Kelly L Summers
- Department of Chemistry , University of Saskatchewan , Saskatoon , Saskatchewan S7N 5C9 , Canada
| | | | - Graham N George
- Department of Geological Sciences , University of Saskatchewan , Saskatoon , Saskatchewan S7N 5E2 , Canada
| | - Deborah B Zamble
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S 3H6 , Canada.,Department of Biochemistry , University of Toronto , Toronto , Ontario M5S 1A8 , Canada
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12
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Abstract
Nickel is an essential cofactor for some pathogen virulence factors. Due to its low availability in hosts, pathogens must efficiently transport the metal and then balance its ready intracellular availability for enzyme maturation with metal toxicity concerns. The most notable virulence-associated components are the Ni-enzymes hydrogenase and urease. Both enzymes, along with their associated nickel transporters, storage reservoirs, and maturation enzymes have been best-studied in the gastric pathogen Helicobacter pylori, a bacterium which depends heavily on nickel. Molecular hydrogen utilization is associated with efficient host colonization by the Helicobacters, which include both gastric and liver pathogens. Translocation of a H. pylori carcinogenic toxin into host epithelial cells is powered by H2 use. The multiple [NiFe] hydrogenases of Salmonella enterica Typhimurium are important in host colonization, while ureases play important roles in both prokaryotic (Proteus mirabilis and Staphylococcus spp.) and eukaryotic (Cryptoccoccus genus) pathogens associated with urinary tract infections. Other Ni-requiring enzymes, such as Ni-acireductone dioxygenase (ARD), Ni-superoxide dismutase (SOD), and Ni-glyoxalase I (GloI) play important metabolic or detoxifying roles in other pathogens. Nickel-requiring enzymes are likely important for virulence of at least 40 prokaryotic and nine eukaryotic pathogenic species, as described herein. The potential for pathogenic roles of many new Ni-binding components exists, based on recent experimental data and on the key roles that Ni enzymes play in a diverse array of pathogens.
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13
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Spronk CAEM, Żerko S, Górka M, Koźmiński W, Bardiaux B, Zambelli B, Musiani F, Piccioli M, Basak P, Blum FC, Johnson RC, Hu H, Merrell DS, Maroney M, Ciurli S. Structure and dynamics of Helicobacter pylori nickel-chaperone HypA: an integrated approach using NMR spectroscopy, functional assays and computational tools. J Biol Inorg Chem 2018; 23:1309-1330. [PMID: 30264175 DOI: 10.1007/s00775-018-1616-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 09/05/2018] [Indexed: 01/03/2023]
Abstract
Helicobacter pylori HypA (HpHypA) is a metallochaperone necessary for maturation of [Ni,Fe]-hydrogenase and urease, the enzymes required for colonization and survival of H. pylori in the gastric mucosa. HpHypA contains a structural Zn(II) site and a unique Ni(II) binding site at the N-terminus. X-ray absorption spectra suggested that the Zn(II) coordination depends on pH and on the presence of Ni(II). This study was performed to investigate the structural properties of HpHypA as a function of pH and Ni(II) binding, using NMR spectroscopy combined with DFT and molecular dynamics calculations. The solution structure of apo,Zn-HpHypA, containing Zn(II) but devoid of Ni(II), was determined using 2D, 3D and 4D NMR spectroscopy. The structure suggests that a Ni-binding and a Zn-binding domain, joined through a short linker, could undergo mutual reorientation. This flexibility has no physiological effect on acid viability or urease maturation in H. pylori. Atomistic molecular dynamics simulations suggest that Ni(II) binding is important for the conformational stability of the N-terminal helix. NMR chemical shift perturbation analysis indicates that no structural changes occur in the Zn-binding domain upon addition of Ni(II) in the pH 6.3-7.2 range. The structure of the Ni(II) binding site was probed using 1H NMR spectroscopy experiments tailored to reveal hyperfine-shifted signals around the paramagnetic metal ion. On this basis, two possible models were derived using quantum-mechanical DFT calculations. The results provide a comprehensive picture of the Ni(II) mode to HpHypA, important to rationalize, at the molecular level, the functional interactions of this chaperone with its protein partners.
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Affiliation(s)
- Chris A E M Spronk
- JSC Spronk, Vilnius, Lithuania.,Department of Molecular and Cell Biology, Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester, UK
| | - Szymon Żerko
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Michał Górka
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland.,Faculty of Physics, Division of Biophysics, Institute of Experimental Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Wiktor Koźmiński
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Benjamin Bardiaux
- Structural Bioinformatics Unit, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3528, Paris, France
| | - Barbara Zambelli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Viale G. Fanin 40, 40127, Bologna, Italy
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Viale G. Fanin 40, 40127, Bologna, Italy
| | - Mario Piccioli
- Center for Magnetic Resonance, Department of Chemistry, University of Florence, Florence, Italy
| | - Priyanka Basak
- Department of Chemistry, University of Massachusetts, Amherst, MA, 01003, USA
| | - Faith C Blum
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| | - Ryan C Johnson
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| | - Heidi Hu
- Department of Chemistry, University of Massachusetts, Amherst, MA, 01003, USA
| | - D Scott Merrell
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| | - Michael Maroney
- Department of Chemistry, University of Massachusetts, Amherst, MA, 01003, USA.
| | - Stefano Ciurli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Viale G. Fanin 40, 40127, Bologna, Italy. .,Center for Magnetic Resonance, Department of Chemistry, University of Florence, Florence, Italy.
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