1
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Kwiatos N, Waldron KJ. In a state of flux: new insight into the transport processes that maintain bacterial metal homeostasis. J Bacteriol 2024:e0014624. [PMID: 38712925 DOI: 10.1128/jb.00146-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024] Open
Abstract
A new study by Nies et al. (J Bacteriol 206:e00080-24, 2024, https://doi.org/10.1128/jb.00080-24) provides a rich, quantitative data set of zinc accumulation by cells of Cupriavidus metallidurans, including of mutant bacterial strains lacking import or efflux genes, and comparison of zinc accumulation by cells previously starved of metal with those of zinc-replete cells. The data surprisingly demonstrate the concomitant activity of both active metal import and metal efflux systems. They present a flow equilibrium model to describe zinc homeostasis in bacteria.
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Affiliation(s)
- Natalia Kwiatos
- Laboratory of Metalloprotein Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Kevin J Waldron
- Laboratory of Metalloprotein Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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2
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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3
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Sendra KM, Barwinska-Sendra A, Mackenzie ES, Baslé A, Kehl-Fie TE, Waldron KJ. An ancient metalloenzyme evolves through metal preference modulation. Nat Ecol Evol 2023; 7:732-744. [PMID: 37037909 PMCID: PMC10172142 DOI: 10.1038/s41559-023-02012-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 02/15/2023] [Indexed: 04/12/2023]
Abstract
Evolution creates functional diversity of proteins, the essential building blocks of all biological systems. However, studies of natural proteins sampled across the tree of life and evaluated in a single experimental system are lacking. Almost half of enzymes require metals, and metalloproteins tend to optimally utilize the physicochemical properties of a specific metal co-factor. Life must adapt to changes in metal bioavailability, including those during the transition from anoxic to oxic Earth or pathogens' exposure to nutritional immunity. These changes can challenge the ability of metalloenzymes to maintain activity, presumptively driving their evolution. Here we studied metal-preference evolution within the natural diversity of the iron/manganese superoxide dismutase (SodFM) family of reactive oxygen species scavengers. We identified and experimentally verified residues with conserved roles in determining metal preference that, when combined with an understanding of the protein's evolutionary history, improved prediction of metal utilization across the five SodFM subfamilies defined herein. By combining phylogenetics, biochemistry and structural biology, we demonstrate that SodFM metal utilization can be evolutionarily fine tuned by sliding along a scale between perfect manganese and iron specificities. Over the history of life, SodFM metal preference has been modulated multiple independent times within different evolutionary and ecological contexts, and can be changed within short evolutionary timeframes.
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Affiliation(s)
- K M Sendra
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
| | - A Barwinska-Sendra
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - E S Mackenzie
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - A Baslé
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - T E Kehl-Fie
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL, USA.
| | - K J Waldron
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
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4
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Rostami N, Shields RC, Serrage HJ, Lawler C, Brittan JL, Yassin S, Ahmed H, Treumann A, Thompson P, Waldron KJ, Nobbs AH, Jakubovics NS. Interspecies competition in oral biofilms mediated by Streptococcus gordonii extracellular deoxyribonuclease SsnA. NPJ Biofilms Microbiomes 2022; 8:96. [PMID: 36509765 PMCID: PMC9744736 DOI: 10.1038/s41522-022-00359-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 11/21/2022] [Indexed: 12/14/2022] Open
Abstract
Extracellular DNA (eDNA) is a key component of many microbial biofilms including dental plaque. However, the roles of extracellular deoxyribonuclease (DNase) enzymes within biofilms are poorly understood. Streptococcus gordonii is a pioneer colonizer of dental plaque. Here, we identified and characterised SsnA, a cell wall-associated protein responsible for extracellular DNase activity of S. gordonii. The SsnA-mediated extracellular DNase activity of S. gordonii was suppressed following growth in sugars. SsnA was purified as a recombinant protein and shown to be inactive below pH 6.5. SsnA inhibited biofilm formation by Streptococcus mutans in a pH-dependent manner. Further, SsnA inhibited the growth of oral microcosm biofilms in human saliva. However, inhibition was ameliorated by the addition of sucrose. Together, these data indicate that S. gordonii SsnA plays a key role in interspecies competition within oral biofilms. Acidification of the medium through sugar catabolism could be a strategy for cariogenic species such as S. mutans to prevent SsnA-mediated exclusion from biofilms.
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Affiliation(s)
- Nadia Rostami
- grid.1006.70000 0001 0462 7212School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Robert C. Shields
- grid.1006.70000 0001 0462 7212School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle, UK ,grid.252381.f0000 0001 2169 5989Department of Biological Sciences, Arkansas State University, Jonesboro, AR USA
| | - Hannah J. Serrage
- grid.5337.20000 0004 1936 7603Bristol Dental School, University of Bristol, Bristol, UK
| | - Catherine Lawler
- grid.5337.20000 0004 1936 7603Bristol Dental School, University of Bristol, Bristol, UK
| | - Jane L. Brittan
- grid.5337.20000 0004 1936 7603Bristol Dental School, University of Bristol, Bristol, UK
| | - Sufian Yassin
- grid.1006.70000 0001 0462 7212School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle, UK ,grid.265892.20000000106344187Department of Restorative Sciences, University of Alabama at Birmingham, Birmingham, AL USA
| | - Halah Ahmed
- grid.1006.70000 0001 0462 7212School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Achim Treumann
- grid.1006.70000 0001 0462 7212Protein and Proteome Analysis Facility, Faculty of Medical Sciences, Newcastle University, Newcastle, UK ,KBI Biopharma BV, Leuven, Belgium
| | - Paul Thompson
- grid.1006.70000 0001 0462 7212Protein and Proteome Analysis Facility, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Kevin J. Waldron
- grid.1006.70000 0001 0462 7212Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Angela H. Nobbs
- grid.5337.20000 0004 1936 7603Bristol Dental School, University of Bristol, Bristol, UK
| | - Nicholas S. Jakubovics
- grid.1006.70000 0001 0462 7212School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
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5
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Zhang P, Li B, Mu J, Liu D, Zhang G, Mao X, Huang K, Waldron KJ, Chen X. The therapeutic and preventive effects of a canine-origin VB 12 -producing Lactobacillus on DSS-induced colitis in mice. J Anim Physiol Anim Nutr (Berl) 2022; 106:1368-1382. [PMID: 36045638 DOI: 10.1111/jpn.13767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 08/01/2022] [Accepted: 08/05/2022] [Indexed: 11/28/2022]
Abstract
Vitamin B12 (VB12 ) plays vital roles as a cofactor in reactions related to biosynthesis and metabolic regulation. Animals with diarrhoea from intestinal inflammation are susceptible to VB12 deficiency due to dysfunctional absorption. No current medications for canine intestinal inflammation can simultaneously act as VB12 supplements. Here we have tested a strain of VB12 -producing Lactobacillus, to investigate its safety in healthy dogs and test for hypothesized therapeutic and preventive effects on murine colitis. Results from enzyme-linked immunosorbent assay, histopathological analysis, and quantitative polymerase chain reaction showed normal physical conditions of healthy dogs given Lactobacillus, and blood biochemical indices showed no significant differences in markers, indicating safety of Lactobacillus to healthy dogs. The microbiota in animals receiving VB12 -producing Lactobacillus probiotic exhibited decreased abundance of Escherichia coli and concomitant increase in Lactobacillus. The probiotic supplement also resulted in downregulation of proinflammatory cytokines in murine colon tissues, reduced myeloperoxidase activity and malondialdehyde level, and significantly increased serum VB12 level and decreased homocysteine in therapeutic and preventive experiments. Moreover, Lactobacillus supplement decreased colonic inflammation and injury, improved gut microbiota, and ameliorated VB12 deficiency as an adjunctive therapy. We conclude this product is potentially beneficial for efficient therapy and prevention of VB12 deficiency form intestinal inflammation in canine clinical practice.
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Affiliation(s)
- Ping Zhang
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Benrui Li
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Jiaxin Mu
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Dandan Liu
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Guoying Zhang
- Department of Clinical Laboratory, Nanjing Integrated Traditional Chinese and Western Medicine Hospital, Nanjing University of Traditional Chinese Medicine, Nanjing, Jiangsu Province, China
| | - Xinru Mao
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Kehe Huang
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Kevin J Waldron
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Xingxiang Chen
- Institute of Animal Nutritional Health, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
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6
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Kaur I, Purves J, Harwood M, Ketley JM, Andrew PW, Waldron KJ, Morrissey JA. Role of horizontally transferred copper resistance genes in Staphylococcus aureus and Listeria monocytogenes. Microbiology (Reading) 2022; 168:001162. [PMID: 35404222 PMCID: PMC10233261 DOI: 10.1099/mic.0.001162] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 02/16/2022] [Indexed: 12/01/2023]
Abstract
Bacteria have evolved mechanisms which enable them to control intracellular concentrations of metals. In the case of transition metals, such as copper, iron and zinc, bacteria must ensure enough is available as a cofactor for enzymes whilst at the same time preventing the accumulation of excess concentrations, which can be toxic. Interestingly, metal homeostasis and resistance systems have been found to play important roles in virulence. This review will discuss the copper homeostasis and resistance systems in Staphylococcus aureus and Listeria monocytogenes and the implications that acquisition of additional copper resistance genes may have in these pathogens.
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Affiliation(s)
- Inderpreet Kaur
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Joanne Purves
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Matthew Harwood
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Julian M. Ketley
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Peter W. Andrew
- Department of Respiratory Sciences, University of Leicester, University, Leicester, LE1 7RH, UK
| | - Kevin J. Waldron
- Biosciences Institute, Newcastle University, Catherine Cookson Building Framlington Place Newcastle upon Tyne NE2 4HH, UK
| | - Julie A. Morrissey
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
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7
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Frye KA, Sendra KM, Waldron KJ, Kehl-Fie TE. Old dogs, new tricks: New insights into the iron/manganese superoxide dismutase family. J Inorg Biochem 2022; 230:111748. [PMID: 35151099 PMCID: PMC9112591 DOI: 10.1016/j.jinorgbio.2022.111748] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/14/2022] [Accepted: 01/30/2022] [Indexed: 12/21/2022]
Abstract
Superoxide dismutases (SODs) are ancient enzymes of widespread importance present in all domains of life. Many insights have been gained into these important enzymes over the 50 years since their initial description, but recent studies in the context of microbial pathogenesis have resulted in findings that challenge long established dogmas. The repertoire of SODs that bacterial pathogens encode is diverse both in number and in metal dependencies, including copper, copper and zinc, manganese, iron, and cambialistic enzymes. Other bacteria also possess nickel dependent SODs. Compartmentalization of SODs only partially explains their diversity. The need for pathogens to maintain SOD activity across distinct hostile environments encountered during infection, including those limited for essential metals, is also a driver of repertoire diversity. SOD research using pathogenic microbes has also revealed the apparent biochemical ease with which metal specificity can change within the most common family of SODs. Collectively, these studies are revealing the dynamic nature of SOD evolution, both that of individual SOD enzymes that can change their metal specificity to adapt to fluctuating cellular metal availability, and of a cell's repertoire of SOD isozymes that can be differentially expressed to adapt to fluctuating environmental metal availability in a niche.
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8
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Ross J, McIver Z, Lambert T, Piergentili C, Bird JE, Gallagher KJ, Cruickshank FL, James P, Zarazúa-Arvizu E, Horsfall LE, Waldron KJ, Wilson MD, Mackay CL, Baslé A, Clarke DJ, Marles-Wright J. Pore dynamics and asymmetric cargo loading in an encapsulin nanocompartment. Sci Adv 2022; 8:eabj4461. [PMID: 35080974 PMCID: PMC8791618 DOI: 10.1126/sciadv.abj4461] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Encapsulins are protein nanocompartments that house various cargo enzymes, including a family of decameric ferritin-like proteins. Here, we study a recombinant Haliangium ochraceum encapsulin:encapsulated ferritin complex using cryo-electron microscopy and hydrogen/deuterium exchange mass spectrometry to gain insight into the structural relationship between the encapsulin shell and its protein cargo. An asymmetric single-particle reconstruction reveals four encapsulated ferritin decamers in a tetrahedral arrangement within the encapsulin nanocompartment. This leads to a symmetry mismatch between the protein cargo and the icosahedral encapsulin shell. The encapsulated ferritin decamers are offset from the interior face of the encapsulin shell. Using hydrogen/deuterium exchange mass spectrometry, we observed the dynamic behavior of the major fivefold pore in the encapsulin shell and show the pore opening via the movement of the encapsulin A-domain. These data will accelerate efforts to engineer the encapsulation of heterologous cargo proteins and to alter the permeability of the encapsulin shell via pore modifications.
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Affiliation(s)
- Jennifer Ross
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
- Newcastle University Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Zak McIver
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Thomas Lambert
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Cecilia Piergentili
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Jasmine Emma Bird
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Kelly J. Gallagher
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Faye L. Cruickshank
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Patrick James
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | | | - Louise E. Horsfall
- School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Kevin J. Waldron
- Newcastle University Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Marcus D. Wilson
- Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Mayfield Road, Edinburgh EH9 3JR, UK
| | - C. Logan Mackay
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Arnaud Baslé
- Newcastle University Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - David J. Clarke
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Jon Marles-Wright
- Newcastle University Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
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9
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Malyar RM, Naseri E, Li H, Ali I, Farid RA, Liu D, Maroof K, Nasim M, Banuree SAH, Huang K, Waldron KJ, Chen X. Hepatoprotective Effects of Selenium-Enriched Probiotics Supplementation on Heat-Stressed Wistar Rat Through Anti-Inflammatory and Antioxidant Effects. Biol Trace Elem Res 2021; 199:3445-3456. [PMID: 33161525 DOI: 10.1007/s12011-020-02475-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/03/2020] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to elucidate the effects of selenium-enriched probiotics on the liver of heat-stressed Wistar rats. Ten-week-old male rats were assigned to four groups: control (Con); high temperature (HT); high temperature plus probiotics (HT + P: 1011 CFU/mL Lactobacillus acidophilus and 109 CFU/mL Saccharomyces cerevisiae); or high temperature plus selenium-enriched probiotics (HT + SeP: 0.3 mg/kg Se, 1011 CFU/mL L. acidophilus and 109 CFU/mL S. cerevisiae). The HT, HT + P, and HT + SeP groups were maintained at higher ambient temperature (40-42 °C), while the control group was kept at room temperature (25 °C). After 42 days of thermal exposure, blood and liver tissues were collected and analyzed for morphological and molecular markers of liver physiology. The body weight of rats in the HT group decreased but liver weight and live index were increased. Histological examination showed dilation of liver sinusoids and congestion of interstitial veins in HT group. Moreover, the histomorphology of the liver in HT + P and HT + SeP groups was restored, and the serum AST, ALT, ALP, LDH, and hepatic MDA level decreased significantly, but the serum total protein level and the liver SOD, T-AOC, and GSH-PX activities were increased significantly relative to the HT group. In addition, the mRNA level of Gpx1, SOD1, Nrf2, and Bcl-2 was significantly increased, while the expression level of Bax, IL-6, TNF-α, COX-2, NF-κB, α-SMA, TGFβ1, Collagen I, HSP70, and HSP90 was significantly decreased in liver tissues after SeP supplementation. We concluded that SeP can protect Wistar rats from oxidative stress, inflammation, apoptosis, and liver fibrosis induced by heat stress.
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Affiliation(s)
- Rahmani Mohammad Malyar
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowl, Nanjing Agricultural University, Nanjing, 210095, China
- Faculty of Veterinary Science, Nangarhar University, Jalalabad, Nangarhar Province, Afghanistan
| | - Emal Naseri
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Ministry of Science and Technology/College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hu Li
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowl, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ilyas Ali
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
| | - Rawan Ahmad Farid
- Faculty of Veterinary Science, Nangarhar University, Jalalabad, Nangarhar Province, Afghanistan
| | - Dandan Liu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowl, Nanjing Agricultural University, Nanjing, 210095, China
| | - Khushdil Maroof
- Faculty of Veterinary Science, Nangarhar University, Jalalabad, Nangarhar Province, Afghanistan
| | - Maazullah Nasim
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Ministry of Science and Technology/College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | | | - Kehe Huang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowl, Nanjing Agricultural University, Nanjing, 210095, China
| | - Kevin J Waldron
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Xingxiang Chen
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowl, Nanjing Agricultural University, Nanjing, 210095, China.
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10
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Giachino A, Focarelli F, Marles-Wright J, Waldron KJ. Synthetic biology approaches to copper remediation: bioleaching, accumulation and recycling. FEMS Microbiol Ecol 2021; 97:6021318. [PMID: 33501489 DOI: 10.1093/femsec/fiaa249] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 12/02/2020] [Indexed: 12/20/2022] Open
Abstract
One of the current aims of synthetic biology is the development of novel microorganisms that can mine economically important elements from the environment or remediate toxic waste compounds. Copper, in particular, is a high-priority target for bioremediation owing to its extensive use in the food, metal and electronic industries and its resulting common presence as an environmental pollutant. Even though microbe-aided copper biomining is a mature technology, its application to waste treatment and remediation of contaminated sites still requires further research and development. Crucially, any engineered copper-remediating chassis must survive in copper-rich environments and adapt to copper toxicity; they also require bespoke adaptations to specifically extract copper and safely accumulate it as a human-recoverable deposit to enable biorecycling. Here, we review current strategies in copper bioremediation, biomining and biorecycling, as well as strategies that extant bacteria use to enhance copper tolerance, accumulation and mineralization in the native environment. By describing the existing toolbox of copper homeostasis proteins from naturally occurring bacteria, we show how these modular systems can be exploited through synthetic biology to enhance the properties of engineered microbes for biotechnological copper recovery applications.
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Affiliation(s)
- Andrea Giachino
- Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Francesca Focarelli
- Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Jon Marles-Wright
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom
| | - Kevin J Waldron
- Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
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11
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Piergentili C, Ross J, He D, Gallagher KJ, Stanley WA, Adam L, Mackay CL, Baslé A, Waldron KJ, Clarke DJ, Marles-Wright J. Dissecting the structural and functional roles of a putative metal entry site in encapsulated ferritins. J Biol Chem 2020; 295:15511-15526. [PMID: 32878987 DOI: 10.1074/jbc.ra120.014502] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/24/2020] [Indexed: 11/06/2022] Open
Abstract
Encapsulated ferritins belong to the universally distributed ferritin superfamily, whose members function as iron detoxification and storage systems. Encapsulated ferritins have a distinct annular structure and must associate with an encapsulin nanocage to form a competent iron store that is capable of holding significantly more iron than classical ferritins. The catalytic mechanism of iron oxidation in the ferritin family is still an open question because of the differences in organization of the ferroxidase catalytic site and neighboring secondary metal-binding sites. We have previously identified a putative metal-binding site on the inner surface of the Rhodospirillum rubrum encapsulated ferritin at the interface between the two-helix subunits and proximal to the ferroxidase center. Here we present a comprehensive structural and functional study to investigate the functional relevance of this putative iron-entry site by means of enzymatic assays, MS, and X-ray crystallography. We show that catalysis occurs in the ferroxidase center and suggest a dual role for the secondary site, which both serves to attract metal ions to the ferroxidase center and acts as a flow-restricting valve to limit the activity of the ferroxidase center. Moreover, confinement of encapsulated ferritins within the encapsulin nanocage, although enhancing the ability of the encapsulated ferritin to undergo catalysis, does not influence the function of the secondary site. Our study demonstrates a novel molecular mechanism by which substrate flux to the ferroxidase center is controlled, potentially to ensure that iron oxidation is productively coupled to mineralization.
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Affiliation(s)
- Cecilia Piergentili
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Jennifer Ross
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, Scotland
| | - Didi He
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh, Scotland
| | - Kelly J Gallagher
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, Scotland
| | - Will A Stanley
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Laurène Adam
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - C Logan Mackay
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, Scotland
| | - Arnaud Baslé
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Kevin J Waldron
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David J Clarke
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, Scotland.
| | - Jon Marles-Wright
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom.
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12
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Sears JD, Waldron KJ, Wei J, Chang CH. Targeting metabolism to reverse T-cell exhaustion in chronic viral infections. Immunology 2020; 162:135-144. [PMID: 32681647 DOI: 10.1111/imm.13238] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/24/2020] [Accepted: 06/28/2020] [Indexed: 12/28/2022] Open
Abstract
CD8 T-cells are an essential component of the adaptive immune response accountable for the clearance of virus-infected cells via cytotoxic effector functions. Maintaining a specific metabolic profile is necessary for these T-cells to sustain their effector functions and clear pathogens. When CD8 T-cells are activated via T-cell receptor recognition of viral antigen, they transition from a naïve to an effector state and eventually to a memory phenotype, and their metabolic profiles shift as the cells differentiate to accomidate different metabolic demands. However, in the context of particular chronic viral infections (CVIs), CD8 T-cells can become metabolically dysfunctional in a state known as T-cell exhaustion. In this state, CD8 T-cells exhibit reduced effector functions and are unable to properly control pathogens. Clearing these chronic infections becomes progressively difficult as increasing numbers of the effector T-cells become exhausted. Hence, reversal of this dysfunctional metabolic phenotype is vital when considering potential treatments of these infections and offers the opportunity for novel strategies for the development of therapies against CVIs. In this review we explore research implicating alteration of the metabolic state as a means to reverse CD8 T-cell exhaustion in CVIs. These findings indicate that strategies targeting dysfunctional CD8 T-cell metabolism could prove to be a promising option for successfully treating CVIs.
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Affiliation(s)
| | | | - Jian Wei
- The Jackson Laboratory, Bar Harbor, ME, USA
| | - Chih-Hao Chang
- The Jackson Laboratory, Bar Harbor, ME, USA.,Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME, USA.,Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
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13
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Giachino A, Waldron KJ. Copper tolerance in bacteria requires the activation of multiple accessory pathways. Mol Microbiol 2020; 114:377-390. [DOI: 10.1111/mmi.14522] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Andrea Giachino
- Biosciences Institute Faculty of Medical Sciences Newcastle University Newcastle upon Tyne UK
| | - Kevin J. Waldron
- Biosciences Institute Faculty of Medical Sciences Newcastle University Newcastle upon Tyne UK
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14
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Tarrant E, P Riboldi G, McIlvin MR, Stevenson J, Barwinska-Sendra A, Stewart LJ, Saito MA, Waldron KJ. Copper stress in Staphylococcus aureus leads to adaptive changes in central carbon metabolism. Metallomics 2020; 11:183-200. [PMID: 30443649 PMCID: PMC6350627 DOI: 10.1039/c8mt00239h] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Copper toxicity has been a long-term selection pressure on bacteria due to its presence in the environment and its use as an antimicrobial agent by grazing protozoa, by phagocytic cells of the immune system, and in man-made medical and commercial products. There is recent evidence that exposure to increased copper stress may have been a key driver in the evolution and spread of methicillin-resistant Staphylococcus aureus, a globally important pathogen that causes significant mortality and morbidity worldwide. Yet it is unclear how S. aureus physiology is affected by copper stress or how it adapts in order to be able to grow in the presence of excess copper. Here, we have determined quantitatively how S. aureus alters its proteome during growth under copper stress conditions, comparing this adaptive response in two different types of growth regime. We found that the adaptive response involves induction of the conserved copper detoxification system as well as induction of enzymes of central carbon metabolism, with only limited induction of proteins involved in the oxidative stress response. Further, we identified a protein that binds copper inside S. aureus cells when stressed by copper excess. This copper-binding enzyme, a glyceraldehyde-3-phosphate dehydrogenase essential for glycolysis, is inhibited by copper in vitro and inside S. aureus cells. Together, our data demonstrate that copper stress leads to the inhibition of glycolysis in S. aureus, and that the bacterium adapts to this stress by altering its central carbon utilisation pathways.
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Affiliation(s)
- Emma Tarrant
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
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15
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Ross J, Lambert T, Piergentili C, He D, Waldron KJ, Mackay CL, Marles-Wright J, Clarke DJ. Mass spectrometry reveals the assembly pathway of encapsulated ferritins and highlights a dynamic ferroxidase interface. Chem Commun (Camb) 2020; 56:3417-3420. [PMID: 32090213 DOI: 10.1039/c9cc08130e] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Encapsulated ferritins (EncFtn) are a recently characterised member of the ferritin superfamily. EncFtn proteins are sequestered within encapsulin nanocompartments and form a unique biological iron storage system. Here, we use native mass spectrometry and hydrogen-deuterium exchange mass spectrometry to elucidate the metal-mediated assembly pathway of EncFtn.
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Affiliation(s)
- Jennifer Ross
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, Scotland, UK.
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16
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Abstract
The insertion of copper into bacterial cuproenzymesin vivodoes not always require a copper-binding metallochaperone – why?
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Affiliation(s)
- Louisa J. Stewart
- Institute for Cell and Molecular Biosciences
- Newcastle University
- Newcastle upon Tyne
- UK
| | - Denis Thaqi
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre
- The University of Queensland
- St Lucia
- Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre
- The University of Queensland
- St Lucia
- Australia
- Institute for Molecular Bioscience
| | - Alastair G. McEwan
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre
- The University of Queensland
- St Lucia
- Australia
| | - Kevin J. Waldron
- Institute for Cell and Molecular Biosciences
- Newcastle University
- Newcastle upon Tyne
- UK
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17
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Patel S, Omid N, Zohoori FV, Maguire A, Waldron KJ, Valentine RA. Comparison of total ionic strength adjustment buffers III and IV in the measurement of fluoride concentration of teas. Nutr Health 2018; 24:111-119. [PMID: 29618287 PMCID: PMC6125819 DOI: 10.1177/0260106018758781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Background: Tea is the second most consumed drink in the UK and a primary source of hydration; it is an important source of dietary fluoride (F) for consumers and also abundant in aluminium (Al). Varying ranges of F concentrations in teas have been reported worldwide which may be, in part, due to differences in analytical techniques used to measure this ion. Aim: The effect of using total ionic adjustment buffers (TISAB) III or IV when measuring F concentration of black teas available in the UK was investigated and compared. Based on this evaluation, the effects of three different infusion times, 1 min, 10 min and 1 h, caffeine content and tea form on the F contents of the tea samples were investigated. Methods: The F concentrations of 47 tea samples were measured directly using a fluoride ion-selective electrode (F-ISE), TISAB III and IV and infusion times of 1 min, 10 min and 1 h. Results: Mean (SD) F concentration of tea samples for all infusion times was statistically significantly higher (p < 0.001) measured by TISAB IV (4.37 (2.16) mg/l) compared with TISAB III (3.54 (1.65) mg/l). A statistically significant positive correlation (p < 0.001) was found between Al concentration (mg/l) and differences in F concentration (mg/l) measured using the two TISABs; the difference in F concentration measured by the two TISABs increased with the magnitude of Al concentration. Conclusion: Due to higher concentrations of F and Al in teas and their complexing potential, use of TISAB IV facilitates more accurate measurement of F concentration when using an F-ISE and a direct method.
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Affiliation(s)
- Shilpa Patel
- 1 Centre for Oral Health Research, Newcastle University, UK
| | - Narges Omid
- 1 Centre for Oral Health Research, Newcastle University, UK
| | | | - Anne Maguire
- 1 Centre for Oral Health Research, Newcastle University, UK
| | - Kevin J Waldron
- 3 Institute for Cell and Molecular Biosciences, Newcastle University, UK
| | - Ruth A Valentine
- 1 Centre for Oral Health Research, Newcastle University, UK.,3 Institute for Cell and Molecular Biosciences, Newcastle University, UK
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18
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Purves J, Thomas J, Riboldi GP, Zapotoczna M, Tarrant E, Andrew PW, Londoño A, Planet PJ, Geoghegan JA, Waldron KJ, Morrissey JA. A horizontally gene transferred copper resistance locus confers hyper-resistance to antibacterial copper toxicity and enables survival of community acquired methicillin resistant Staphylococcus aureus USA300 in macrophages. Environ Microbiol 2018. [PMID: 29521441 PMCID: PMC5947656 DOI: 10.1111/1462-2920.14088] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Excess copper is highly toxic and forms part of the host innate immune system's antibacterial arsenal, accumulating at sites of infection and acting within macrophages to kill engulfed pathogens. We show for the first time that a novel, horizontally gene transferred copper resistance locus (copXL), uniquely associated with the SCCmec elements of the highly virulent, epidemic, community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) USA300, confers copper hyper-resistance. These genes are additional to existing core genome copper resistance mechanisms, and are not found in typical S. aureus lineages, but are increasingly identified in emerging pathogenic isolates. Our data show that CopX, a putative P1B-3 -ATPase efflux transporter, and CopL, a novel lipoprotein, confer copper hyper-resistance compared to typical S. aureus strains. The copXL genes form an operon that is tightly repressed in low copper environments by the copper regulator CsoR. Significantly, CopX and CopL are important for S. aureus USA300 intracellular survival within macrophages. Therefore, the emergence of new S. aureus clones with the copXL locus has significant implications for public health because these genes confer increased resistance to antibacterial copper toxicity, enhancing bacterial fitness by altering S. aureus interaction with innate immunity.
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Affiliation(s)
- Joanne Purves
- Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Jamie Thomas
- Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Gustavo P Riboldi
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Marta Zapotoczna
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Ireland
| | - Emma Tarrant
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Peter W Andrew
- Department of Infection, Immunity and Inflammation, University of Leicester, University Road, Leicester, LE1 9HN, UK
| | | | - Paul J Planet
- Department of Pediatrics, Columbia University, New York, NY, USA.,Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joan A Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Ireland
| | - Kevin J Waldron
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Julie A Morrissey
- Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH, UK
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19
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Barwinska-Sendra A, Baslé A, Waldron KJ, Un S. A charge polarization model for the metal-specific activity of superoxide dismutases. Phys Chem Chem Phys 2018; 20:2363-2372. [PMID: 29308487 PMCID: PMC5901066 DOI: 10.1039/c7cp06829h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The pathogenicity of Staphylococcus aureus is enhanced by having two superoxide dismutases (SODs): a Mn-specific SOD and another that can use either Mn or Fe. Using 94 GHz electron-nuclear double resonance (ENDOR) and electron double resonance detected (ELDOR)-NMR we show that, despite their different metal-specificities, their structural and electronic similarities extend down to their active-site 1H- and 14N-Mn(ii) hyperfine interactions. However these interactions, and hence the positions of these nuclei, are different in the inactive Mn-reconstituted Escherichia coli Fe-specific SOD. Density functional theory modelling attributes this to a different angular position of the E. coli H171 ligand. This likely disrupts the Mn-H171-E170' triad causing a shift in charge and in metal redox potential, leading to the loss of activity. This is supported by the correlated differences in the Mn(ii) zero-field interactions of the three SOD types and suggests that the triad is important for determining metal specific activity.
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Affiliation(s)
- Anna Barwinska-Sendra
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
| | - Arnaud Baslé
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
| | - Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
| | - Sun Un
- Department of Biochemistry, Biophysics and Structural Biology, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS UMR 9198, CEA-Saclay, Gif-sur-Yvette, F-91198, France.
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20
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Abstract
The metals manganese, iron, cobalt, nickel, copper and zinc are essential for almost all bacteria, but their precise metal requirements vary by species, by ecological niche and by growth condition. Bacteria thus must acquire each of these essential elements in sufficient quantity to satisfy their cellular demand, but in excess these same elements are toxic. Metal toxicity has been exploited by humanity for centuries, and by the mammalian immune system for far longer, yet the mechanisms by which these elements cause toxicity to bacteria are not fully understood. There has been a resurgence of interest in metal toxicity in recent decades due to the problematic spread of antibiotic resistance amongst bacterial pathogens, which has led to an increased research effort to understand these toxicity mechanisms at the molecular level. A recurring theme from these studies is the role of intermetal competition in bacterial metal toxicity. In this review, we first survey biological metal usage and introduce some fundamental chemical concepts that are important for understanding bacterial metal usage and toxicity. Then we introduce a simple model by which to understand bacterial metal homeostasis in terms of the distribution of each essential metal ion within cellular 'pools', and dissect how these pools interact with each other and with key proteins of bacterial metal homeostasis. Finally, using a number of key examples from the recent literature, we look at specific metal toxicity mechanisms in model bacteria, demonstrating the role of metal-metal competition in the toxicity mechanisms of diverse essential metals.
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Affiliation(s)
- Anna Barwinska-Sendra
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Kevin J Waldron
- Institute for Cell & Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom.
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21
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Garcia YM, Barwinska-Sendra A, Tarrant E, Skaar EP, Waldron KJ, Kehl-Fie TE. A Superoxide Dismutase Capable of Functioning with Iron or Manganese Promotes the Resistance of Staphylococcus aureus to Calprotectin and Nutritional Immunity. PLoS Pathog 2017; 13:e1006125. [PMID: 28103306 PMCID: PMC5245786 DOI: 10.1371/journal.ppat.1006125] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 12/14/2016] [Indexed: 11/19/2022] Open
Abstract
Staphylococcus aureus is a devastating mammalian pathogen for which the development of new therapeutic approaches is urgently needed due to the prevalence of antibiotic resistance. During infection pathogens must overcome the dual threats of host-imposed manganese starvation, termed nutritional immunity, and the oxidative burst of immune cells. These defenses function synergistically, as host-imposed manganese starvation reduces activity of the manganese-dependent enzyme superoxide dismutase (SOD). S. aureus expresses two SODs, denoted SodA and SodM. While all staphylococci possess SodA, SodM is unique to S. aureus, but the advantage that S. aureus gains by expressing two apparently manganese-dependent SODs is unknown. Surprisingly, loss of both SODs renders S. aureus more sensitive to host-imposed manganese starvation, suggesting a role for these proteins in overcoming nutritional immunity. In this study, we have elucidated the respective contributions of SodA and SodM to resisting oxidative stress and nutritional immunity. These analyses revealed that SodA is important for resisting oxidative stress and for disease development when manganese is abundant, while SodM is important under manganese-deplete conditions. In vitro analysis demonstrated that SodA is strictly manganese-dependent whereas SodM is in fact cambialistic, possessing equal enzymatic activity when loaded with manganese or iron. Cumulatively, these studies provide a mechanistic rationale for the acquisition of a second superoxide dismutase by S. aureus and demonstrate an important contribution of cambialistic SODs to bacterial pathogenesis. Furthermore, they also suggest a new mechanism for resisting manganese starvation, namely populating manganese-utilizing enzymes with iron.
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Affiliation(s)
- Yuritzi M. Garcia
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, IL, United States of America
| | - Anna Barwinska-Sendra
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Emma Tarrant
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Eric P. Skaar
- Department of Pathology Microbiology and Immunology, Vanderbilt University Medical Center Nashville TN, United States of America
| | - Kevin J. Waldron
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Thomas E. Kehl-Fie
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, IL, United States of America
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22
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Vita N, Landolfi G, Baslé A, Platsaki S, Lee J, Waldron KJ, Dennison C. Bacterial cytosolic proteins with a high capacity for Cu(I) that protect against copper toxicity. Sci Rep 2016; 6:39065. [PMID: 27991525 PMCID: PMC5171941 DOI: 10.1038/srep39065] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/16/2016] [Indexed: 01/23/2023] Open
Abstract
Bacteria are thought to avoid using the essential metal ion copper in their cytosol due to its toxicity. Herein we characterize Csp3, the cytosolic member of a new family of bacterial copper storage proteins from Methylosinus trichosporium OB3b and Bacillus subtilis. These tetrameric proteins possess a large number of Cys residues that point into the cores of their four-helix bundle monomers. The Csp3 tetramers can bind a maximum of approximately 80 Cu(I) ions, mainly via thiolate groups, with average affinities in the (1–2) × 1017 M−1 range. Cu(I) removal from these Csp3s by higher affinity potential physiological partners and small-molecule ligands is very slow, which is unexpected for a metal-storage protein. In vivo data demonstrate that Csp3s prevent toxicity caused by the presence of excess copper. Furthermore, bacteria expressing Csp3 accumulate copper and are able to safely maintain large quantities of this metal ion in their cytosol. This suggests a requirement for storing copper in this compartment of Csp3-producing bacteria.
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Affiliation(s)
- Nicolas Vita
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Gianpiero Landolfi
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Arnaud Baslé
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Semeli Platsaki
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Jaeick Lee
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Christopher Dennison
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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23
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He D, Hughes S, Vanden-Hehir S, Georgiev A, Altenbach K, Tarrant E, Mackay CL, Waldron KJ, Clarke DJ, Marles-Wright J. Structural characterization of encapsulated ferritin provides insight into iron storage in bacterial nanocompartments. eLife 2016; 5. [PMID: 27529188 PMCID: PMC5012862 DOI: 10.7554/elife.18972] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 08/14/2016] [Indexed: 12/17/2022] Open
Abstract
Ferritins are ubiquitous proteins that oxidise and store iron within a protein shell to protect cells from oxidative damage. We have characterized the structure and function of a new member of the ferritin superfamily that is sequestered within an encapsulin capsid. We show that this encapsulated ferritin (EncFtn) has two main alpha helices, which assemble in a metal dependent manner to form a ferroxidase center at a dimer interface. EncFtn adopts an open decameric structure that is topologically distinct from other ferritins. While EncFtn acts as a ferroxidase, it cannot mineralize iron. Conversely, the encapsulin shell associates with iron, but is not enzymatically active, and we demonstrate that EncFtn must be housed within the encapsulin for iron storage. This encapsulin nanocompartment is widely distributed in bacteria and archaea and represents a distinct class of iron storage system, where the oxidation and mineralization of iron are distributed between two proteins. DOI:http://dx.doi.org/10.7554/eLife.18972.001 Iron is essential for life as it is a key component of many different enzymes that participate in processes such as energy production and metabolism. However, iron can also be highly toxic to cells because it readily reacts with oxygen. This reaction can damage DNA, proteins and the membranes that surround cells. To balance the cell’s need for iron against its potential damaging effects, organisms have evolved iron storage proteins known as ferritins that form cage-like structures. The ferritins convert iron into a less reactive form that is mineralised and safely stored in the central cavity of the ferritin cage and is available for cells when they need it. Recently, a new family of ferritins known as encapsulated ferritins have been found in some microorganisms. These ferritins are found in bacterial genomes with a gene that codes for a protein cage called an encapsulin. Although the structure of the encapsulin cage is known to look like the shell of a virus, the structure that the encapsulated ferritin itself forms is not known. It is also not clear how encapsulin and the encapsulated ferritin work together to store iron. He et al. have now used the techniques of X-ray crystallography and mass spectrometry to determine the structure of the encapsulated ferritin found in some bacteria. The encapsulated ferritin forms a ring-shaped doughnut in which ten subunits of ferritin are arranged in a ring; this is totally different from the enclosed cages that other ferritins form. Biochemical studies revealed that the encapsulated ferritin is able to convert iron into a less reactive form, but it cannot store iron on its own since it does not form a cage. Thus, the encapsulated ferritin needs to be housed within the encapsulin cage to store iron. Further work is needed to investigate how iron moves into the encapsulin cage to reach the ferritin proteins. Some organisms have both standard ferritin cages and encapsulated ferritins; why this is the case also remains to be discovered. DOI:http://dx.doi.org/10.7554/eLife.18972.002
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Affiliation(s)
- Didi He
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Sam Hughes
- The School of Chemistry, The University of Edinburgh, Edinburgh, United Kingdom
| | - Sally Vanden-Hehir
- The School of Chemistry, The University of Edinburgh, Edinburgh, United Kingdom
| | - Atanas Georgiev
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Kirsten Altenbach
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Emma Tarrant
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcasle upon Tyne, United Kingdom
| | - C Logan Mackay
- The School of Chemistry, The University of Edinburgh, Edinburgh, United Kingdom
| | - Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcasle upon Tyne, United Kingdom
| | - David J Clarke
- The School of Chemistry, The University of Edinburgh, Edinburgh, United Kingdom
| | - Jon Marles-Wright
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom.,School of Biology, Newcastle University, Newcastle upon Tyne, United Kingdom
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Abellón-Ruiz J, Waldron KJ, Connolly BA. Archaeoglobus Fulgidus DNA Polymerase D: A Zinc-Binding Protein Inhibited by Hypoxanthine and Uracil. J Mol Biol 2016; 428:2805-13. [PMID: 27320386 PMCID: PMC4942837 DOI: 10.1016/j.jmb.2016.06.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/28/2016] [Accepted: 06/13/2016] [Indexed: 02/03/2023]
Abstract
Archaeal family-D DNA polymerases (Pol-D) comprise a small (DP1) proofreading subunit and a large (DP2) polymerase subunit. Pol-D is one of the least studied polymerase families, and this publication investigates the enzyme from Archaeoglobus fulgidus (Afu Pol-D). The C-terminal region of DP2 contains two conserved cysteine clusters, and their roles are investigated using site-directed mutagenesis. The cluster nearest the C terminus is essential for polymerase activity, and the cysteines are shown to serve as ligands for a single, critical Zn(2+) ion. The cysteines farthest from the C terminal were not required for activity, and a role for these amino acids has yet to be defined. Additionally, it is shown that Afu Pol-D activity is slowed by the template strand hypoxanthine, extending previous results that demonstrated inhibition by uracil. Hypoxanthine was a weaker inhibitor than uracil. Investigations with isolated DP2, which has a measurable polymerase activity, localised the deaminated base binding site to this subunit. Uracil and hypoxanthine slowed Afu Pol-D "in trans", that is, a copied DNA strand could be inhibited by a deaminated base in the alternate strand of a replication fork. The error rate of Afu Pol-D, measured in vitro, was 0.24×10(-5), typical for a polymerase that has been proposed to carry out genome replication in the Archaea. Deleting the 3'-5' proofreading exonuclease activity reduced fidelity twofold. The results presented in this publication considerably increase our knowledge of Pol-D.
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Affiliation(s)
- Javier Abellón-Ruiz
- Institute for Cell and Molecular Biology, University of Newcastle, Newcastle upon Tyne NE2 4HH, UK
| | - Kevin J Waldron
- Institute for Cell and Molecular Biology, University of Newcastle, Newcastle upon Tyne NE2 4HH, UK
| | - Bernard A Connolly
- Institute for Cell and Molecular Biology, University of Newcastle, Newcastle upon Tyne NE2 4HH, UK.
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25
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Ikeh MAC, Kastora SL, Day AM, Herrero-de-Dios CM, Tarrant E, Waldron KJ, Banks AP, Bain JM, Lydall D, Veal EA, MacCallum DM, Erwig LP, Brown AJP, Quinn J. Pho4 mediates phosphate acquisition in Candida albicans and is vital for stress resistance and metal homeostasis. Mol Biol Cell 2016; 27:2784-801. [PMID: 27385340 PMCID: PMC5007097 DOI: 10.1091/mbc.e16-05-0266] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 06/23/2016] [Indexed: 12/02/2022] Open
Abstract
This study provides the first evidence that the phosphate-responsive transcription factor Pho4 is vital for survival of Candida albicans to diverse and physiologically relevant stresses. Pho4 is important for C. albicans pathogenesis, and thus these findings illustrate how metabolic adaptation promotes C. albicans survival in the host. During interactions with its mammalian host, the pathogenic yeast Candida albicans is exposed to a range of stresses such as superoxide radicals and cationic fluxes. Unexpectedly, a nonbiased screen of transcription factor deletion mutants revealed that the phosphate-responsive transcription factor Pho4 is vital for the resistance of C. albicans to these diverse stresses. RNA-Seq analysis indicated that Pho4 does not induce stress-protective genes directly. Instead, we show that loss of Pho4 affects metal cation toxicity, accumulation, and bioavailability. We demonstrate that pho4Δ cells are sensitive to metal and nonmetal cations and that Pho4-mediated polyphosphate synthesis mediates manganese resistance. Significantly, we show that Pho4 is important for mediating copper bioavailability to support the activity of the copper/zinc superoxide dismutase Sod1 and that loss of Sod1 activity contributes to the superoxide sensitivity of pho4Δ cells. Consistent with the key role of fungal stress responses in countering host phagocytic defenses, we also report that C. albicans pho4Δ cells are acutely sensitive to macrophage-mediated killing and display attenuated virulence in animal infection models. The novel connections between phosphate metabolism, metal homeostasis, and superoxide stress resistance presented in this study highlight the importance of metabolic adaptation in promoting C. albicans survival in the host.
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Affiliation(s)
- Mélanie A C Ikeh
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Stavroula L Kastora
- School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Alison M Day
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | | | - Emma Tarrant
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - A Peter Banks
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Judith M Bain
- School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - David Lydall
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Elizabeth A Veal
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Donna M MacCallum
- School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Lars P Erwig
- School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Alistair J P Brown
- School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Janet Quinn
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
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Vita N, Platsaki S, Baslé A, Allen SJ, Paterson NG, Crombie AT, Murrell JC, Waldron KJ, Dennison C. A four-helix bundle stores copper for methane oxidation. Nature 2015; 525:140-3. [PMID: 26308900 PMCID: PMC4561512 DOI: 10.1038/nature14854] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 06/23/2015] [Indexed: 11/09/2022]
Abstract
Methane-oxidizing bacteria (methanotrophs) require large quantities of copper for the membrane-bound (particulate) methane monooxygenase. Certain methanotrophs are also able to switch to using the iron-containing soluble methane monooxygenase to catalyse methane oxidation, with this switchover regulated by copper. Methane monooxygenases are nature's primary biological mechanism for suppressing atmospheric levels of methane, a potent greenhouse gas. Furthermore, methanotrophs and methane monooxygenases have enormous potential in bioremediation and for biotransformations producing bulk and fine chemicals, and in bioenergy, particularly considering increased methane availability from renewable sources and hydraulic fracturing of shale rock. Here we discover and characterize a novel copper storage protein (Csp1) from the methanotroph Methylosinus trichosporium OB3b that is exported from the cytosol, and stores copper for particulate methane monooxygenase. Csp1 is a tetramer of four-helix bundles with each monomer binding up to 13 Cu(I) ions in a previously unseen manner via mainly Cys residues that point into the core of the bundle. Csp1 is the first example of a protein that stores a metal within an established protein-folding motif. This work provides a detailed insight into how methanotrophs accumulate copper for the oxidation of methane. Understanding this process is essential if the wide-ranging biotechnological applications of methanotrophs are to be realized. Cytosolic homologues of Csp1 are present in diverse bacteria, thus challenging the dogma that such organisms do not use copper in this location.
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Affiliation(s)
- Nicolas Vita
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Semeli Platsaki
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Arnaud Baslé
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Stephen J Allen
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Neil G Paterson
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Andrew T Crombie
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Christopher Dennison
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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27
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Gorniak JP, Cameron KM, Waldron KJ, von Zglinicki T, Mathers JC, Langie SAS. Tissue differences in BER-related incision activity and non-specific nuclease activity as measured by the comet assay. Mutagenesis 2013; 28:673-81. [PMID: 24097409 DOI: 10.1093/mutage/get047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
DNA repair mechanisms are important for genome stability and to prevent accumulation of DNA damage, which contributes to cellular ageing and cancer development. Study of these physiological processes requires robust and practical assays to quantify DNA repair capacity. The in vitro comet-based assay is a simple, yet reliable, assay for measurement of DNA repair and has been modified recently to quantify DNA incision activity in mouse brain and liver. In this study, we applied this assay to assess DNA incision activity in other mouse tissues, i.e. lung and colon, and found that high, non-specific nuclease activity was a problem when measuring DNA incision activity, especially in the colon. We tested the utility of multiple optimisation steps including addition of aphidicolin, ATP and polyAT and used multiple wash steps, which resulted in modest improvements in performance of the assay. Washing the tissues before protein extraction and decreasing the protein concentration in the assay were the most effective steps in reducing non-specific nuclease activity. Using the comet-based assay with these further modifications, we found that base excision repair incision activity changed with age differently in each tissue. This study shows that non-specific nuclease activity in the comet-based assay for DNA repair is more pronounced in some tissues than others so care should be taken to optimise the protocol when applying the assay to a new tissue. Our data suggest the importance of using control cells (noRo cells incubated with extract) in the assay to assess for non-specific nuclease activity. In conclusion, the comet-based DNA repair assay can be easily adapted to study a range of mammalian tissues.
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Affiliation(s)
- Joanna P Gorniak
- Centre for Brain Ageing and Vitality, Human Nutrition Research Centre, Institute for Ageing & Health, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
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Langie SAS, Cameron KM, Waldron KJ, Fletcher KPR, von Zglinicki T, Mathers JC. Measuring DNA repair incision activity of mouse tissue extracts towards singlet oxygen-induced DNA damage: a comet-based in vitro repair assay. Mutagenesis 2011; 26:461-71. [PMID: 21355044 DOI: 10.1093/mutage/ger005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
During the past two decades, the comet-based in vitro DNA repair assay has been used regularly to measure base excision repair (BER)-related DNA incision activity. Most studies focus on the assessment of BER in human lymphocytes or cultured cells by estimating the activity of a cell extract on substrate DNA containing specific lesions such as 8-oxoguanine. However, for many 'real-life' studies, it would be preferable to measure BER in the tissues of interest instead of using in vitro models or surrogate 'tissues' such as lymphocytes. Various attempts have been made to use the comet-based repair assay for BER with extracts from rodent tissues, but high non-specific nuclease activity in such tissues were a significant impediment to robust estimates of BER. Our aim in this study was to optimise the in vitro repair assay for BER for use with rodent tissues using extracts from liver and brain from C57/BL mice. Because the DNA incision activity of an extract is dependent on its protein concentration, the first optimisation step in preventing interference by non-specific nuclease activity was to determine the protein concentration at which there is a maximal difference between the total and non-specific damage recognition. This protein concentration was 5 mg/ml for mouse liver extracts and 1 mg/ml for brain extracts. Next, we tested addition of proteinase inhibitors during the preparation of the tissue extracts, but this did not improve the sensitivity of the assay. However, addition of 1.5 μM aphidicolin to the tissue extracts improved the detection of DNA repair incision activity by reducing non-specific nuclease activity and possibly by blocking residual DNA polymerase activity. Finally, the assay was tested on tissue samples from an ageing mouse colony and in mice undergoing dietary restriction and proved capable of detecting significant inter-animal differences and nutritional effects on BER-related DNA incision activity.
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Affiliation(s)
- Sabine A S Langie
- Centre for Brain Ageing and Vitality, Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
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Waldron KJ, Firbank SJ, Dainty SJ, Pérez-Rama M, Tottey S, Robinson NJ. Structure and metal loading of a soluble periplasm cuproprotein. J Biol Chem 2010; 285:32504-11. [PMID: 20702411 DOI: 10.1074/jbc.m110.153080] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A copper-trafficking pathway was found to enable Cu(2+) occupancy of a soluble periplasm protein, CucA, even when competing Zn(2+) is abundant in the periplasm. Here, we solved the structure of CucA (a new cupin) and found that binding of Cu(2+), but not Zn(2+), quenches the fluorescence of Trp(165), which is adjacent to the metal site. Using this fluorescence probe, we established that CucA becomes partly occupied by Zn(2+) following exposure to equimolar Zn(2+) and Cu(2+). Cu(2+)-CucA is more thermodynamically stable than Zn(2+)-CucA but k((Zn→Cu)exchange) is slow, raising questions about how the periplasm contains solely the Cu(2+) form. We discovered that a copper-trafficking pathway involving two copper transporters (CtaA and PacS) and a metallochaperone (Atx1) is obligatory for Cu(2+)-CucA to accumulate in the periplasm. There was negligible CucA protein in the periplasm of ΔctaA cells, but the abundance of cucA transcripts was unaltered. Crucially, ΔctaA cells overaccumulate low M(r) copper complexes in the periplasm, and purified apoCucA can readily acquire Cu(2+) from ΔctaA periplasm extracts, but in vivo apoCucA fails to come into contact with these periplasmic copper pools. Instead, copper traffics via a cytoplasmic pathway that is coupled to CucA translocation to the periplasm.
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Affiliation(s)
- Kevin J Waldron
- Institute for Cell and Molecular Biosciences, University of Newcastle Medical School, Newcastle upon Tyne NE2 4HH, United Kingdom
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30
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Osman D, Waldron KJ, Denton H, Taylor CM, Grant AJ, Mastroeni P, Robinson NJ, Cavet JS. Copper homeostasis in Salmonella is atypical and copper-CueP is a major periplasmic metal complex. J Biol Chem 2010; 285:25259-68. [PMID: 20534583 PMCID: PMC2919089 DOI: 10.1074/jbc.m110.145953] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Salmonella enterica sv. typhimurium (S. enterica sv. Typhimurium) has two metal-transporting P(1)-type ATPases whose actions largely overlap with respect to growth in elevated copper. Mutants lacking both ATPases over-accumulate copper relative to wild-type or either single mutant. Such duplication of ATPases is unusual in bacterial copper tolerance. Both ATPases are under the control of MerR family metal-responsive transcriptional activators. Analyses of periplasmic copper complexes identified copper-CueP as one of the predominant metal pools. Expression of cueP was recently shown to be controlled by the same metal-responsive activator as one of the P(1)-type ATPase genes (copA), and copper-CueP is a further atypical feature of copper homeostasis in S. enterica sv. Typhimurium. Elevated copper is detected by a reporter construct driven by the promoter of copA in wild-type S. enterica sv. Typhimurium during infection of macrophages. Double mutants missing both ATPases also show reduced survival inside cultured macrophages. It is hypothesized that elevated copper within macrophages may have selected for specialized copper-resistance systems in pathogenic microorganism such as S. enterica sv. Typhimurium.
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Affiliation(s)
- Deenah Osman
- Life Sciences, Michael Smith Building, University of Manchester, United Kingdom
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Abstract
Almost half of all enzymes must associate with a particular metal to function. An ambition is to understand why each metal-protein partnership arose and how it is maintained. Metal availability provides part of the explanation, and has changed over geological time and varies between habitats but is held within vital limits in cells. Such homeostasis needs metal sensors, and there is an ongoing search to discover the metal-sensing mechanisms. For metalloproteins to acquire the right metals, metal sensors must correctly distinguish between the inorganic elements.
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Affiliation(s)
- Kevin J Waldron
- Cell & Molecular Biosciences, Medical School, Newcastle University, Newcastle NE2 4HH, UK
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32
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Banci L, Bertini I, Ciofi-Baffoni S, Poggi L, Vanarotti M, Tottey S, Waldron KJ, Robinson NJ. NMR structural analysis of the soluble domain of ZiaA-ATPase and the basis of selective interactions with copper metallochaperone Atx1. J Biol Inorg Chem 2009; 15:87-98. [DOI: 10.1007/s00775-009-0568-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Accepted: 06/29/2009] [Indexed: 10/20/2022]
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Dainty SJ, Patterson CJ, Waldron KJ, Robinson NJ. Interaction between cyanobacterial copper chaperone Atx1 and zinc homeostasis. J Biol Inorg Chem 2009; 15:77-85. [PMID: 19543924 DOI: 10.1007/s00775-009-0555-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 06/05/2009] [Indexed: 11/26/2022]
Abstract
Cyanobacterial Atx1 is a copper chaperone which interacts with two copper-transporting ATPases to assist copper supply to plastocyanin and cytochrome oxidase. ZiaA is a Zn(2+)-exporting ATPase and ziaA expression is regulated by ZiaR. Here we show that gene expression from the ziaA operator promoter, monitored using reverse transcriptase PCR and lacZ fusions, is elevated in Deltaatx1 mutants. Although Cu(+) tightly binds recombinant ZiaR in vitro, Cu(+) is less effective at dissociating ZiaR-DNA complexes than Zn(2+) and crucially ziaA expression responds to Zn(2+) but not copper in both wild-type and Deltaatx1 cells. Consistent with enhanced expression of ZiaA, Deltaatx1 cells have slightly elevated Zn(2+) resistance. Recombinant Zn(2+)-Atx1 is recovered from Zn(2+)-supplemented Escherichia coli and even after copper supplementation substantial amounts of Zn(2+)-Atx1 are isolated. Taken together, these data suggest that Zn(2+)-Atx1 can form in vivo.
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Affiliation(s)
- Samantha J Dainty
- Institute for Cell and Molecular Bioscience, Newcastle University, UK
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Tottey S, Waldron KJ, Firbank SJ, Reale B, Bessant C, Sato K, Cheek TR, Gray J, Banfield MJ, Dennison C, Robinson NJ. Protein-folding location can regulate manganese-binding versus copper- or zinc-binding. Nature 2008; 455:1138-42. [DOI: 10.1038/nature07340] [Citation(s) in RCA: 253] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Accepted: 08/13/2008] [Indexed: 01/22/2023]
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Hung MH, Orin DE, Waldron KJ. Efficient formulation of the force distribution equations for general tree-structured robotic mechanisms with a mobile base. IEEE Trans Syst Man Cybern B Cybern 2008; 30:529-38. [PMID: 18252384 DOI: 10.1109/3477.865170] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this paper, an efficient and systematic formulation of the force distribution equations for general tree-structured robotic mechanisms is presented. The applicable platforms include not only systems with star topologies, such as walking machines that have multiple legs with a single body but also general tree-structured mechanisms, such as variably configured wheeled vehicles having multiple modules. The force balance equations that govern the relationship between the contact forces and the resultant inertial forces/moments of the vehicle will be derived through a recursive and computationally efficient algorithm. Also, the joint torque constraints that specify the joint actuator limits, and contact friction constraints that may be used to avoid slippage and maintain contact, are efficiently incorporated in the formulation. Based on this formulation, several standard optimization techniques, such as linear programming or quadratic programming, can be applied to obtain the solution. An algorithm summarizing the results developed, and suitable for computer implementation, is included. The algorithm has been applied to an n-module actively articulated wheeled vehicle, and the computational cost evaluated. The efficiency of the algorithm is demonstrated with results showing real-time execution on a Pentium PC.
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Affiliation(s)
- M H Hung
- Dept. of Electr. Eng., Chung Cheng Inst. of Technol., Taoyuan
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37
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Badarau A, Firbank SJ, Waldron KJ, Yanagisawa S, Robinson NJ, Banfield MJ, Dennison C. FutA2 is a ferric binding protein from Synechocystis PCC 6803. J Biol Chem 2008; 283:12520-7. [PMID: 18252722 DOI: 10.1074/jbc.m709907200] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Synechocystis PCC 6803 has a high demand for iron (10 times greater than Escherichia coli) to sustain photosynthesis and is unusual in possessing at least two putative iron-binding proteins of a type normally associated with ATP-binding cassette-type importers. It has been suggested that one of these, FutA2, binds ferrous iron, but herein we clearly demonstrate that this protein avidly binds Fe(III), the oxidation state preference of periplasmic iron-binding proteins. Structures of apo-FutA2 and Fe-FutA2 have been determined at 1.7 and 2.7A, respectively. The metal ion is bound in a distorted trigonal bipyramidal arrangement with no exogenous anions as ligands. The metal-binding environment, including the second coordination sphere and charge properties, is consistent with a preference for Fe(III). Atypically, FutA2 has a Tat signal peptide, and its inability to coordinate divalent cations may be crucial to prevent metals from binding to the folded protein prior to export from the cytosol. A loop containing the His(43) ligand undergoes considerable movement in apo-versus Fe-FutA2 and may control metal release to the importer. Although these data are consistent with FutA2 being the periplasmic component involved in iron uptake, deletion of another putative ferric binding protein, FutA1, has a greater effect on the accumulation of iron and is more analogous to a DeltafutA1DeltafutA2 double mutant than DeltafutA2. Here, we also discover that there is a reduced level of ferric FutA2 in the periplasm of the DeltafutA1 mutant providing an explanation for its severe iron-uptake phenotype.
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Affiliation(s)
- Adriana Badarau
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
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38
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Campbell DR, Chapman KE, Waldron KJ, Tottey S, Kendall S, Cavallaro G, Andreini C, Hinds J, Stoker NG, Robinson NJ, Cavet JS. Mycobacterial cells have dual nickel-cobalt sensors: sequence relationships and metal sites of metal-responsive repressors are not congruent. J Biol Chem 2007; 282:32298-310. [PMID: 17726022 PMCID: PMC3145109 DOI: 10.1074/jbc.m703451200] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A novel ArsR-SmtB family transcriptional repressor, KmtR, has been characterized from mycobacteria. Mutants of Mycobacterium tuberculosis lacking kmtR show elevated expression of Rv2025c encoding a deduced CDF-family metal exporter. KmtR-dependent repression of the cdf and kmtR operator-promoters was alleviated by nickel and cobalt in minimal medium. Electrophoretic mobility shift assays and fluorescence anisotropy show binding of purified KmtR to nucleotide sequences containing a region of dyad symmetry from the cdf and kmtR operator-promoters. Incubation of KmtR with cobalt inhibits DNA complex assembly and metal-protein binding was confirmed. KmtR is the second, to NmtR, characterized ArsR-SmtB sensor of nickel and cobalt from M. tuberculosis suggesting special significance for these ions in this pathogen. KmtR-dependent expression is elevated in complete medium with no increase in response to metals, whereas NmtR retains a response to nickel and cobalt under these conditions. KmtR has tighter affinities for nickel and cobalt than NmtR consistent with basal levels of these metals being sensed by KmtR but not NmtR in complete medium. More than a thousand genes encoding ArsR-SmtB-related proteins are listed in databases. KmtR has none of the previously defined metal-sensing sites. Substitution of His88, Glu101, His102, His110, or His111 with Gln generated KmtR variants that repress the cdf and kmtR operator-promoters even in elevated nickel and cobalt, revealing a new sensory site. Importantly, ArsR-SmtB sequence groupings do not correspond with the different sensory motifs revealing that only the latter should be used to predict metal sensing.
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Affiliation(s)
- Duncan R. Campbell
- Life Sciences, University of Manchester, 1.800 Stopford Building, Manchester M13 9PT, United Kingdom
| | - Kaye E. Chapman
- Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle NE2 4HH, United Kingdom
| | - Kevin J. Waldron
- Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle NE2 4HH, United Kingdom
| | - Stephen Tottey
- Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle NE2 4HH, United Kingdom
| | - Sharon Kendall
- The Royal Veterinary College, Royal College Street, London NW1 0TU, United Kingdom
| | - Gabriele Cavallaro
- Magnetic Resonance Centre, University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine Paramagnetiche, 50019 Sesto Fiorentino, Florence, Italy
| | - Claudia Andreini
- Magnetic Resonance Centre, University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine Paramagnetiche, 50019 Sesto Fiorentino, Florence, Italy
| | - Jason Hinds
- Bacterial Microarray Group, St. George’s University of London, London SW17 0RE, United Kingdom
| | - Neil G. Stoker
- The Royal Veterinary College, Royal College Street, London NW1 0TU, United Kingdom
| | - Nigel J. Robinson
- Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle NE2 4HH, United Kingdom
- To whom correspondence may be addressed: Tel. 44-191-222-7695; Fax: 44-191-222-7424;
| | - Jennifer S. Cavet
- Life Sciences, University of Manchester, 1.800 Stopford Building, Manchester M13 9PT, United Kingdom
- To whom correspondence may be addressed: Tel. 44-161-275-51543; Fax: 44-161-275-5656;
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Abstract
Periplasmic substrate binding proteins are known for iron, zinc, manganese, nickel, and molybdenum but not copper. Synechocystis PCC 6803 requires copper for thylakoid-localized plastocyanin and cytochrome oxidase. Here we show that mutants deficient in a periplasmic substrate binding protein FutA2 have low cytochrome oxidase activity and produce cytochrome c6 when grown under copper conditions (150 nm) in which wild-type cells use plastocyanin rather than cytochrome c6. Anaerobic separation of extracts by two-dimensional native liquid chromatography followed by metal analysis and peptide mass-fingerprinting establish that accumulation of copper-plastocyanin is impaired, but iron-ferredoxin is unaffected in DeltafutA2 grown in 150 nm copper. However, recombinant FutA2 binds iron in preference to copper in vitro with an apparent Fe(III) affinity similar to that of its paralog FutA1, the principal substrate binding protein for iron import. FutA2 is also associated with iron and not copper in periplasm extracts, and this Fe(III)-protein complex is absent in DeltafutA2. There are differences in the soluble protein and small-molecule complexes of copper and iron, and the total amount of both elements increases in periplasm extracts of DeltafutA2 relative to wild type. Changes in periplasm protein and small-molecule complexes for other metals are also observed in DeltafutA2. It is proposed that FutA2 contributes to metal partitioning in the periplasm by sequestering Fe(III), which limits aberrant Fe(III) associations with vital binding sites for other metals, including copper.
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Affiliation(s)
- Kevin J Waldron
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle NE4 2HH, United Kingdom
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40
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Angeletti B, Waldron KJ, Freeman KB, Bawagan H, Hussain I, Miller CCJ, Lau KF, Tennant ME, Dennison C, Robinson NJ, Dingwall C. BACE1 cytoplasmic domain interacts with the copper chaperone for superoxide dismutase-1 and binds copper. J Biol Chem 2005; 280:17930-7. [PMID: 15722349 DOI: 10.1074/jbc.m412034200] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The amyloidogenic pathway leading to the production and deposition of Abeta peptides, major constituents of Alzheimer disease senile plaques, is linked to neuronal metal homeostasis. The amyloid precursor protein binds copper and zinc in its extracellular domain, and the Abeta peptides also bind copper, zinc, and iron. The first step in the generation of Abeta is cleavage of amyloid precursor protein by the aspartic protease BACE1. Here we show that BACE1 interacts with CCS (the copper chaperone for superoxide dismutase-1 (SOD1)) through domain I and the proteins co-immunoprecipitate from rat brain extracts. We have also been able to visualize the co-transport of membranous BACE1 and soluble CCS through axons. BACE1 expression reduces the activity of SOD1 in cells consistent with direct competition for available CCS as overexpression of CCS restores SOD1 activity. Finally, we demonstrate that the twenty-four residue C-terminal domain of BACE1 binds a single Cu(I) atom with high affinity through cysteine residues.
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Affiliation(s)
- Barbara Angeletti
- Neurology & Gastrointestinal Centre of Excellence for Drug Discovery, GlaxoSmithKline, New Frontiers Science Park, Harlow, Essex CM19 5AW, United Kingdom
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41
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Abstract
In this paper, the dynamics of quadruped trot, gallop, and bound will be examined using a simple model for the quadruped. The body of the quadruped is modeled as a uniform bar and the legs are modeled by massless springs. It will be shown that symmetry can be used to study the locomotion of this system. Using symmetry, a technique will be developed to obtain periodic solutions for each of the gaits of the quadruped model. These periodic solutions will be computed at various speeds. The energy levels will be compared for each of the gaits. The exchange of energy between its different forms will be shown for different gaits. It will be shown that even without body flexibility, there are significant savings in energy due to gait transition from trot to gallop. The energy levels will be used to predict the trot-gallop transition speed. These results will be compared with the experimental results for horses and dogs.
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Affiliation(s)
- P Nanua
- Power Systems Research Dept., General Motors R&D Center, Warren, Ml 48090, USA
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42
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Abstract
This paper presents a dynamical analysis of quadrupedal locomotion, with specific reference to an adult Nubian goat. Measurements of ground reaction forces and limb motion are used to assess variations in intersegmental forces, joint moments, and instantaneous power for three discernible gaits: walking, running, and jumping. In each case, inertial effects of the torso are shown to dominate to the extent that lower-extremity contributions may be considered negligible. Footforces generated by the forelimbs exceed those exerted by the hindlimbs; and, in general, ground reactions increase with speed. The shoulder and hip dominate mechanical energy production during walking, while the knee plays a more significant role in running. In both cases, however, the elbow absorbs energy, and by so doing functions primarily as a damping (control) element. As opposed to either walking or running, jumping requires total horizontal retardation of the body's center of mass. In this instance, generating the necessary vertical thrust amounts to energy absorption at all joints of the lower extremities.
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Affiliation(s)
- M G Pandy
- Department of Mechanical Engineering, Ohio State University, Columbus 43210
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Churches AE, Howlett CR, Waldron KJ, Ward GW. The response of living bone to controlled time-varying loading: method and preliminary results. J Biomech 1979; 12:35-45. [PMID: 762180 DOI: 10.1016/0021-9290(79)90007-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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