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Mukherjee P, Agarwal S, Mallick SB, Dasgupta J. PAS domain of flagellar histidine kinase FlrB has a unique architecture and binds heme as a sensory ligand in an unconventional fashion. Structure 2024; 32:200-216.e5. [PMID: 38157857 DOI: 10.1016/j.str.2023.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/28/2023] [Accepted: 11/29/2023] [Indexed: 01/03/2024]
Abstract
Phosphorylation of the σ54-dependent transcription activator FlrC by the sensor histidine kinase FlrB is essential for flagellar synthesis of Vibrio cholerae. Despite that, the structure, sensory signal, and mechanistic basis of function of FlrB were elusive. Here, we report the crystal structure of the sensory PAS domain of FlrB in its functional dimeric state that exhibits a unique architecture. Series of biochemical/biophysical experiments on different constructs and mutants established that heme binds hydrophobically as sensory ligand in the shallow ligand-binding cleft of FlrB-PAS without axial coordination. Intriguingly, ATP binding to the C-terminal ATP-binding (CA) domain assists PAS domain to bind heme, vis-à-vis, heme binding to the PAS facilitates ATP binding to the CA domain. We hypothesize that synergistic binding of heme and ATP triggers conformational signaling in FlrB, leading to downstream flagellar gene transcription. Enhanced swimming motility of V. cholerae with increased heme uptake supports this proposition.
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Affiliation(s)
- Peeali Mukherjee
- Department of Biotechnology, St. Xavier's College (Autonomous), 30 Mother Teresa Sarani, Kolkata 700016, India
| | - Shubhangi Agarwal
- Department of Biotechnology, St. Xavier's College (Autonomous), 30 Mother Teresa Sarani, Kolkata 700016, India
| | - Sritapa Basu Mallick
- Department of Biotechnology, St. Xavier's College (Autonomous), 30 Mother Teresa Sarani, Kolkata 700016, India
| | - Jhimli Dasgupta
- Department of Biotechnology, St. Xavier's College (Autonomous), 30 Mother Teresa Sarani, Kolkata 700016, India.
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2
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Zamarreño Beas J, Videira MAM, Karavaeva V, Lourenço FM, Almeida MR, Sousa F, Saraiva LM. In Campylobacter jejuni, a new type of chaperone receives heme from ferrochelatase. Front Genet 2023; 14:1199357. [PMID: 37415606 PMCID: PMC10320005 DOI: 10.3389/fgene.2023.1199357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/02/2023] [Indexed: 07/08/2023] Open
Abstract
Intracellular heme formation and trafficking are fundamental processes in living organisms. Bacteria and archaea utilize three biogenesis pathways to produce iron protoporphyrin IX (heme b) that diverge after the formation of the common intermediate uroporphyrinogen III (uro'gen III). In this study, we identify and provide a detailed characterization of the enzymes involved in the transformation of uro'gen III into heme in Campylobacter jejuni, demonstrating that this bacterium utilizes the protoporphyrin-dependent (PPD) pathway. In general, limited knowledge exists regarding the mechanisms by which heme b reaches its target proteins after this final step. Specifically, the chaperones necessary for trafficking heme to prevent the cytotoxic effects associated with free heme remain largely unidentified. In C. jejuni, we identified a protein named CgdH2 that binds heme with a dissociation constant of 4.9 ± 1.0 µM, and this binding is impaired upon mutation of residues histidine 45 and 133. We demonstrate that C. jejuni CgdH2 establishes protein-protein interactions with ferrochelatase, suggesting its role in facilitating heme transfer from ferrochelatase to CgdH2. Furthermore, phylogenetic analysis reveals that C. jejuni CgdH2 is evolutionarily distinct from the currently known chaperones. Therefore, CgdH2 is the first protein identified as an acceptor of intracellularly formed heme, expanding our knowledge of the mechanisms underlying heme trafficking within bacterial cells.
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Affiliation(s)
- Jordi Zamarreño Beas
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Marco A. M. Videira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Val Karavaeva
- Department of Functional and Evolutionary Ecology, University of Vienna, Wien, Austria
| | - Frederico M. Lourenço
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Mafalda R. Almeida
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Filipa Sousa
- Department of Functional and Evolutionary Ecology, University of Vienna, Wien, Austria
| | - Lígia M. Saraiva
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
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3
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Huete SG, Benaroudj N. The Arsenal of Leptospira Species against Oxidants. Antioxidants (Basel) 2023; 12:1273. [PMID: 37372003 DOI: 10.3390/antiox12061273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/01/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Reactive oxygen species (ROS) are byproducts of oxygen metabolism produced by virtually all organisms living in an oxic environment. ROS are also produced by phagocytic cells in response to microorganism invasion. These highly reactive molecules can damage cellular constituents (proteins, DNA, and lipids) and exhibit antimicrobial activities when present in sufficient amount. Consequently, microorganisms have evolved defense mechanisms to counteract ROS-induced oxidative damage. Leptospira are diderm bacteria form the Spirochaetes phylum. This genus is diverse, encompassing both free-living non-pathogenic bacteria as well as pathogenic species responsible for leptospirosis, a widespread zoonotic disease. All leptospires are exposed to ROS in the environment, but only pathogenic species are well-equipped to sustain the oxidative stress encountered inside their hosts during infection. Importantly, this ability plays a pivotal role in Leptospira virulence. In this review, we describe the ROS encountered by Leptospira in their different ecological niches and outline the repertoire of defense mechanisms identified so far in these bacteria to scavenge deadly ROS. We also review the mechanisms controlling the expression of these antioxidants systems and recent advances in understanding the contribution of Peroxide Stress Regulators in Leptospira adaptation to oxidative stress.
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Affiliation(s)
- Samuel G Huete
- Institut Pasteur, Université Paris Cité, Biologie des Spirochètes, CNRS UMR 6047, F-75015 Paris, France
| | - Nadia Benaroudj
- Institut Pasteur, Université Paris Cité, Biologie des Spirochètes, CNRS UMR 6047, F-75015 Paris, France
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4
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Zavala-Alvarado C, Sismeiro O, Legendre R, Varet H, Bussotti G, Bayram J, G. Huete S, Rey G, Coppée JY, Picardeau M, Benaroudj N. The transcriptional response of pathogenic Leptospira to peroxide reveals new defenses against infection-related oxidative stress. PLoS Pathog 2020; 16:e1008904. [PMID: 33021995 PMCID: PMC7567364 DOI: 10.1371/journal.ppat.1008904] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 10/16/2020] [Accepted: 08/19/2020] [Indexed: 11/19/2022] Open
Abstract
Pathogenic Leptospira spp. are the causative agents of the waterborne zoonotic disease leptospirosis. Leptospira are challenged by numerous adverse conditions, including deadly reactive oxygen species (ROS), when infecting their hosts. Withstanding ROS produced by the host innate immunity is an important strategy evolved by pathogenic Leptospira for persisting in and colonizing hosts. In L. interrogans, genes encoding defenses against ROS are repressed by the peroxide stress regulator, PerR. In this study, RNA sequencing was performed to characterize both the L. interrogans response to low and high concentrations of hydrogen peroxide and the PerR regulon. We showed that Leptospira solicit three main peroxidase machineries (catalase, cytochrome C peroxidase and peroxiredoxin) and heme to detoxify oxidants produced during peroxide stress. In addition, canonical molecular chaperones of the heat shock response and DNA repair proteins from the SOS response were required for Leptospira recovering from oxidative damage. Identification of the PerR regulon upon exposure to H2O2 allowed to define the contribution of this regulator in the oxidative stress response. This study has revealed a PerR-independent regulatory network involving other transcriptional regulators, two-component systems and sigma factors as well as non-coding RNAs that putatively orchestrate, in concert with PerR, the oxidative stress response. We have shown that PerR-regulated genes encoding a TonB-dependent transporter and a two-component system (VicKR) are involved in Leptospira tolerance to superoxide. This could represent the first defense mechanism against superoxide in L. interrogans, a bacterium lacking canonical superoxide dismutase. Our findings provide an insight into the mechanisms required by pathogenic Leptospira to overcome oxidative damage during infection-related conditions. This will participate in framing future hypothesis-driven studies to identify and decipher novel virulence mechanisms in this life-threatening pathogen. Leptospirosis is a zoonotic infectious disease responsible for over one million of severe cases and 60 000 fatalities annually worldwide. This neglected and emerging disease has a worldwide distribution, but it mostly affects populations from developing countries in sub-tropical areas. The causative agents of leptospirosis are pathogenic bacterial Leptospira spp. There is a considerable deficit in our knowledge of these atypical bacteria, including their virulence mechanisms. During infection, Leptospira are confronted with the deadly oxidants produced by the host tissues and immune response. Here, we have identified the leptospiral factors necessary for overcoming infection-related oxidative stress. We found that Leptospira solicit peroxidases to detoxify oxidants as well as chaperones of the heat shock response and DNA repair proteins of the SOS response to recover from oxidative damage. Moreover, our study indicates that the oxidative stress response is orchestrated by a regulatory network involving PerR and other transcriptional regulators, sigma factors, two component systems, and putative non-coding RNAs. These findings provide insights into the mechanisms required by pathogenic Leptospira to tolerate infection-related oxidants and could help identifying novel virulence factors and developing new therapeutic targets.
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Affiliation(s)
- Crispin Zavala-Alvarado
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
- Université de Paris, Sorbonne Paris Cité, COMUE BioSPC, Paris, France
| | - Odile Sismeiro
- Biomics Technological Plateform, Center for Technological Resources and Research, Institut Pasteur, Paris, France
| | - Rachel Legendre
- Biomics Technological Plateform, Center for Technological Resources and Research, Institut Pasteur, Paris, France
- Bioinformatics and Biostatistics Hub, Department of Computational Biology, USR 3756 CNRS, Institut Pasteur, Paris, France
| | - Hugo Varet
- Biomics Technological Plateform, Center for Technological Resources and Research, Institut Pasteur, Paris, France
- Bioinformatics and Biostatistics Hub, Department of Computational Biology, USR 3756 CNRS, Institut Pasteur, Paris, France
| | - Giovanni Bussotti
- Bioinformatics and Biostatistics Hub, Department of Computational Biology, USR 3756 CNRS, Institut Pasteur, Paris, France
| | - Jan Bayram
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
| | - Samuel G. Huete
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
| | - Guillaume Rey
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
| | - Jean-Yves Coppée
- Biomics Technological Plateform, Center for Technological Resources and Research, Institut Pasteur, Paris, France
| | - Mathieu Picardeau
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
| | - Nadia Benaroudj
- Unité de Biologie des Spirochètes, Department of Microbiology, Institut Pasteur, Paris, France
- * E-mail:
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5
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Golz JC, Epping L, Knüver MT, Borowiak M, Hartkopf F, Deneke C, Malorny B, Semmler T, Stingl K. Whole genome sequencing reveals extended natural transformation in Campylobacter impacting diagnostics and the pathogens adaptive potential. Sci Rep 2020; 10:3686. [PMID: 32111893 PMCID: PMC7048796 DOI: 10.1038/s41598-020-60320-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 02/05/2020] [Indexed: 11/09/2022] Open
Abstract
Campylobacter is the major bacterial agent of human gastroenteritis worldwide and represents a crucial global public health burden. Species differentiation of C. jejuni and C. coli and phylogenetic analysis is challenged by inter-species horizontal gene transfer. Routine real-time PCR on more than 4000 C. jejuni and C. coli field strains identified isolates with ambiguous PCR results for species differentiation, in particular, from the isolation source eggs. K-mer analysis of whole genome sequencing data indicated the presence of C. coli hybrid strains with huge amounts of C. jejuni introgression. Recombination events were distributed over the whole chromosome. MLST typing was impaired, since C. jejuni sequences were also found in six of the seven housekeeping genes. cgMLST suggested that the strains were phylogenetically unrelated. Intriguingly, the strains shared a stress response set of C. jejuni variant genes, with proposed roles in oxidative, osmotic and general stress defence, chromosome maintenance and repair, membrane transport, cell wall and capsular biosynthesis and chemotaxis. The results have practical impact on routine typing and on the understanding of the functional adaption to harsh environments, enabling successful spreading and persistence of Campylobacter.
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Affiliation(s)
- Julia C Golz
- German Federal Institute for Risk Assessment, Department of Biological Safety, National Reference Laboratory for Campylobacter, Berlin, Germany
| | - Lennard Epping
- Robert Koch Institute, Microbial Genomics, Berlin, Germany
| | - Marie-Theres Knüver
- German Federal Institute for Risk Assessment, Department of Biological Safety, National Reference Laboratory for Campylobacter, Berlin, Germany
| | - Maria Borowiak
- German Federal Institute for Risk Assessment, Department of Biological Safety, Study Centre for Genome Sequencing and Analysis, Berlin, Germany
| | - Felix Hartkopf
- Robert Koch Institute, Microbial Genomics, Berlin, Germany
| | - Carlus Deneke
- German Federal Institute for Risk Assessment, Department of Biological Safety, Study Centre for Genome Sequencing and Analysis, Berlin, Germany
| | - Burkhard Malorny
- German Federal Institute for Risk Assessment, Department of Biological Safety, Study Centre for Genome Sequencing and Analysis, Berlin, Germany
| | | | - Kerstin Stingl
- German Federal Institute for Risk Assessment, Department of Biological Safety, National Reference Laboratory for Campylobacter, Berlin, Germany.
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6
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Martínez-Sernández V, Mezo M, González-Warleta M, Perteguer MJ, Gárate T, Romarís F, Ubeira FM. Delineating distinct heme-scavenging and -binding functions of domains in MF6p/helminth defense molecule (HDM) proteins from parasitic flatworms. J Biol Chem 2017; 292:8667-8682. [PMID: 28348084 DOI: 10.1074/jbc.m116.771675] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/17/2017] [Indexed: 12/27/2022] Open
Abstract
MF6p/FhHDM-1 is a small protein secreted by the parasitic flatworm (trematode) Fasciola hepatica that belongs to a broad family of heme-binding proteins (MF6p/helminth defense molecules (HDMs)). MF6p/HDMs are of interest for understanding heme homeostasis in trematodes and as potential targets for the development of new flukicides. Moreover, interest in these molecules has also increased because of their immunomodulatory properties. Here we have extended our previous findings on the mechanism of MF6p/HDM-heme interactions and mapped the protein regions required for heme binding and for other biological functions. Our data revealed that MF6p/FhHDM-1 forms high-molecular-weight complexes when associated with heme and that these complexes are reorganized by a stacking procedure to form fibril-like and granular nanostructures. Furthermore, we showed that MF6p/FhHDM-1 is a transitory heme-binding protein as protein·heme complexes can be disrupted by contact with an apoprotein (e.g. apomyoglobin) with higher affinity for heme. We also demonstrated that (i) the heme-binding region is located in the MF6p/FhHDM-1 C-terminal moiety, which also inhibits the peroxidase-like activity of heme, and (ii) MF6p/HDMs from other trematodes, such as Opisthorchis viverrini and Paragonimus westermani, also bind heme. Finally, we observed that the N-terminal, but not the C-terminal, moiety of MF6p/HDMs has a predicted structural analogy with cell-penetrating peptides and that both the entire protein and the peptide corresponding to the N-terminal moiety of MF6p/FhHDM-1 interact in vitro with cell membranes in hemin-preconditioned erythrocytes. Our findings suggest that MF6p/HDMs can transport heme in trematodes and thereby shield the parasite from the harmful effects of heme.
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Affiliation(s)
- Victoria Martínez-Sernández
- From the Laboratorio de Parasitología, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Mercedes Mezo
- the Laboratorio de Parasitología, Centro de Investigaciones Agrarias de Mabegondo, Instituto Galego da Calidade Alimentaria (INGACAL), 15318 Abegondo, A Coruña, Spain, and
| | - Marta González-Warleta
- the Laboratorio de Parasitología, Centro de Investigaciones Agrarias de Mabegondo, Instituto Galego da Calidade Alimentaria (INGACAL), 15318 Abegondo, A Coruña, Spain, and
| | - María J Perteguer
- the Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain
| | - Teresa Gárate
- the Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain
| | - Fernanda Romarís
- From the Laboratorio de Parasitología, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Florencio M Ubeira
- From the Laboratorio de Parasitología, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain,
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7
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Flint A, Stintzi A, Saraiva LM. Oxidative and nitrosative stress defences of Helicobacter and Campylobacter species that counteract mammalian immunity. FEMS Microbiol Rev 2016; 40:938-960. [PMID: 28201757 PMCID: PMC5091033 DOI: 10.1093/femsre/fuw025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/29/2016] [Accepted: 07/02/2016] [Indexed: 12/18/2022] Open
Abstract
Helicobacter and Campylobacter species are Gram-negative microaerophilic host-associated heterotrophic bacteria that invade the digestive tract of humans and animals. Campylobacter jejuni is the major worldwide cause of foodborne gastroenteritis in humans, while Helicobacter pylori is ubiquitous in over half of the world's population causing gastric and duodenal ulcers. The colonisation of the gastrointestinal system by Helicobacter and Campylobacter relies on numerous cellular defences to sense the host environment and respond to adverse conditions, including those imposed by the host immunity. An important antimicrobial tool of the mammalian innate immune system is the generation of harmful oxidative and nitrosative stresses to which pathogens are exposed during phagocytosis. This review summarises the regulators, detoxifying enzymes and subversion mechanisms of Helicobacter and Campylobacter that ultimately promote the successful infection of humans.
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Affiliation(s)
- Annika Flint
- Ottawa Institute of Systems Biology, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Alain Stintzi
- Ottawa Institute of Systems Biology, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Lígia M. Saraiva
- Instituto de Tecnologia Química e Biológica, NOVA, Av. da República, 2780-157 Oeiras, Portugal
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Handley RA, Mulholland F, Reuter M, Ramachandran VK, Musk H, Clissold L, Le Brun NE, van Vliet AHM. PerR controls oxidative stress defence and aerotolerance but not motility-associated phenotypes of Campylobacter jejuni. MICROBIOLOGY-SGM 2015; 161:1524-36. [PMID: 25968890 DOI: 10.1099/mic.0.000109] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The foodborne bacterial pathogen Campylobacter jejuni is an obligate microaerophile that is exposed to atmospheric oxygen during transmission through the food chain. Survival under aerobic conditions requires the concerted control of oxidative stress systems, which in C. jejuni are intimately connected with iron metabolism via the PerR and Fur regulatory proteins. Here, we have characterized the roles of C. jejuni PerR in oxidative stress and motility phenotypes, and its regulon at the level of transcription, protein expression and promoter interactions. Insertional inactivation of perR in the C. jejuni reference strains NCTC 11168, 81-176 and 81116 did not result in any growth deficiencies, but strongly increased survival in atmospheric oxygen conditions, and allowed growth around filter discs infused with up to 30 % H2O2 (8.8 M). Expression of catalase, alkyl hydroperoxide reductase, thioredoxin reductase and the Rrc desulforubrerythrin was increased in the perR mutant, and this was mediated at the transcriptional level as shown by electrophoretic mobility shift assays of the katA, ahpC and trxB promoters using purified PerR. Differential RNA-sequencing analysis of a fur perR mutant allowed the identification of eight previously unknown transcription start sites of genes controlled by Fur and/or PerR. Finally, inactivation of perR in C. jejuni did not result in reduced motility, and did not reduce killing of Galleria melonella wax moth larvae. In conclusion, PerR plays an important role in controlling oxidative stress resistance and aerobic survival of C. jejuni, but this role does not extend into control of motility and associated phenotypes.
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Affiliation(s)
- Rebecca A Handley
- 1 Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK 2 Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Francis Mulholland
- 1 Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
| | - Mark Reuter
- 1 Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
| | | | - Heather Musk
- 4 The Genome Analysis Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Leah Clissold
- 4 The Genome Analysis Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Nick E Le Brun
- 2 Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Arnoud H M van Vliet
- 1 Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
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