2023
Clostridioides difficile ferrosome organelles combat nutritional immunity
Pi H, Sun R, McBride J, Kruse A, Gibson-Corley K, Krystofiak E, Nicholson M, Spraggins J, Zhou Q, Skaar E. Clostridioides difficile ferrosome organelles combat nutritional immunity. Nature 2023, 623: 1009-1016. PMID: 37968387, PMCID: PMC10822667, DOI: 10.1038/s41586-023-06719-9.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBacterial ProteinsCell MembraneClostridioides difficileClostridium InfectionsCryoelectron MicroscopyDisease Models, AnimalElectron Microscope TomographyFerric CompoundsHomeostasisHost Microbial InteractionsInflammationIntestinesIronLeukocyte L1 Antigen ComplexMiceMicrobial ViabilityOrganellesConceptsFerric uptake regulator FurCryo-electron tomographyRegulator FurGram-negative bacteriaMembrane proteinsNutritional immunityIron uptakeCellular membranesDetoxification strategiesIron homeostasisForms of lifeStore ironBacterial pathogensIron sequestrationBiomineralization processPhosphate biomineralsRecent studiesImportant roleBacterial colonizationOrganellesInflamed gutMouse modelProteinTransportersHomeostasis
2022
Bacterial hydrophilins promote pathogen desiccation tolerance
Green E, Fakhoury J, Monteith A, Pi H, Giedroc D, Skaar E. Bacterial hydrophilins promote pathogen desiccation tolerance. Cell Host & Microbe 2022, 30: 975-987.e7. PMID: 35413266, PMCID: PMC9283220, DOI: 10.1016/j.chom.2022.03.019.Peer-Reviewed Original ResearchAn RNA-binding protein acts as a major post-transcriptional modulator in Bacillus anthracis
Pi H, Weiss A, Laut C, Grunenwald C, Lin H, Yi X, Stauff D, Skaar E. An RNA-binding protein acts as a major post-transcriptional modulator in Bacillus anthracis. Nature Communications 2022, 13: 1491. PMID: 35314695, PMCID: PMC8938561, DOI: 10.1038/s41467-022-29209-4.Peer-Reviewed Original ResearchMeSH KeywordsBacillus anthracisBacterial ProteinsCell WallGene Expression Regulation, BacterialHumansRNA-Binding ProteinsConceptsHuman pathogen Bacillus anthracisRNA-binding proteinPost-transcriptional modulatorsPathogen Bacillus anthracisDetectable nuclease activityTwo-component systemBacillus anthracisGenetic competenceRNA turnoverDNA repairMRNA stabilityCellular metabolismNuclease activityEnvelope damageRNAProteinMultiple processesAnthracisHITRSporulationGenesMRNAExpressionMetabolismTurnoverA Central Role for Magnesium Homeostasis during Adaptation to Osmotic Stress
Wendel B, Pi H, Krüger L, Herzberg C, Stülke J, Helmann J. A Central Role for Magnesium Homeostasis during Adaptation to Osmotic Stress. MBio 2022, 13: e00092-22. PMID: 35164567, PMCID: PMC8844918, DOI: 10.1128/mbio.00092-22.Peer-Reviewed Original ResearchMeSH KeywordsBacterial ProteinsCyclic AMPDehydrationHomeostasisHumansMagnesiumOsmotic PressurePotassiumConceptsResumption of growthOsmotic stressCompatible solutesCellular responsesBacillus subtilisDomains of lifeHigh salt stressCommon cellular responseEssential second messengerSpecific efflux pumpsSalt stressProtein translationOsmotic upshiftHyperosmotic stressSecond messengerHigh osmolarityReimportLiving cellsTransient growth inhibitionEfflux pumpsModel system
2021
DnaJ and ClpX Are Required for HitRS and HssRS Two-Component System Signaling in Bacillus anthracis
Laut C, Leasure C, Pi H, Carlin S, Chu M, Hillebrand G, Lin H, Yi X, Stauff D, Skaar E. DnaJ and ClpX Are Required for HitRS and HssRS Two-Component System Signaling in Bacillus anthracis. Infection And Immunity 2021, 90: e00560-21. PMID: 34748369, PMCID: PMC8788696, DOI: 10.1128/iai.00560-21.Peer-Reviewed Original ResearchConceptsTwo-component systemGene expressionSubstrate-binding subunitSignal transduction activityTarget gene expressionB. anthracisBacillus anthracisGram-positive bacteriumHost-induced stressesClpXP proteaseProtein chaperonesSignal transductionClpXGene productsTransduction activityDnaJVertebrate hostsHeme levelsHomeostasis regulatorGenetic selectionHigh heme levelsCell envelope disruptionBioterror weaponHssRSAnthracis
2020
Directed evolution reveals the mechanism of HitRS signaling transduction in Bacillus anthracis
Pi H, Chu M, Ivan S, Latario C, Toth A, Carlin S, Hillebrand G, Lin H, Reppart J, Stauff D, Skaar E. Directed evolution reveals the mechanism of HitRS signaling transduction in Bacillus anthracis. PLOS Pathogens 2020, 16: e1009148. PMID: 33362282, PMCID: PMC7790381, DOI: 10.1371/journal.ppat.1009148.Peer-Reviewed Original ResearchMeSH KeywordsBacillus anthracisBacterial ProteinsGene Expression Regulation, BacterialSelection, GeneticSignal TransductionStress, PhysiologicalConceptsHAMP domainSignal transductionGenetic selectionUnbiased genetic selectionCell envelope stressPathogen Bacillus anthracisSignal transduction systemImportant signal transduction systemMechanistic understandingBacillus anthracisComprehensive mechanistic understandingNumerous point mutationsEnvelope stressTransduction systemMolecular basisMutational analysisPoint mutationsTransductionRate-limiting stepIndividual domainsSpecific interactionsSignal sensingHITRAnthracisSystematic characterizationDysregulation of Magnesium Transport Protects Bacillus subtilis against Manganese and Cobalt Intoxication
Pi H, Wendel B, Helmann J. Dysregulation of Magnesium Transport Protects Bacillus subtilis against Manganese and Cobalt Intoxication. Journal Of Bacteriology 2020, 202: 10.1128/jb.00711-19. PMID: 31964700, PMCID: PMC7167470, DOI: 10.1128/jb.00711-19.Peer-Reviewed Original Research
2017
Sequential induction of Fur-regulated genes in response to iron limitation in Bacillus subtilis
Pi H, Helmann J. Sequential induction of Fur-regulated genes in response to iron limitation in Bacillus subtilis. Proceedings Of The National Academy Of Sciences Of The United States Of America 2017, 114: 12785-12790. PMID: 29133393, PMCID: PMC5715773, DOI: 10.1073/pnas.1713008114.Peer-Reviewed Original ResearchConceptsFerric uptake regulatorHigh-affinity FeIron availabilityPerR regulonFur regulonSiderophore bacillibactinGenetic toolsChIP experimentsIron limitationCell transitionBacillus subtilisHigh-affinity bindingIron homeostasisBacterial cellsIntracellular ironSequential inductionRegulonBacillibactinEnzyme accessVivo occupancyGenesFurIron poolIron sufficiencyEfflux transportersFerrous iron efflux systems in bacteria
Pi H, Helmann J. Ferrous iron efflux systems in bacteria. Metallomics 2017, 9: 840-851. PMID: 28604884, PMCID: PMC5675029, DOI: 10.1039/c7mt00112f.Peer-Reviewed Original Research
2016
The Listeria monocytogenes Fur‐regulated virulence protein FrvA is an Fe(II) efflux P1B4‐type ATPase
Pi H, Patel S, Argüello J, Helmann J. The Listeria monocytogenes Fur‐regulated virulence protein FrvA is an Fe(II) efflux P1B4‐type ATPase. Molecular Microbiology 2016, 100: 1066-1079. PMID: 26946370, PMCID: PMC4914386, DOI: 10.1111/mmi.13368.Peer-Reviewed Original Research
2015
Discovery of Antibiotic (E)‑3-(3-Carboxyphenyl)-2-(4-cyanostyryl)quinazolin-4(3H)‑one
Bouley R, Kumarasiri M, Peng Z, Otero L, Song W, Suckow M, Schroeder V, Wolter W, Lastochkin E, Antunes N, Pi H, Vakulenko S, Hermoso J, Chang M, Mobashery S. Discovery of Antibiotic (E)‑3-(3-Carboxyphenyl)-2-(4-cyanostyryl)quinazolin-4(3H)‑one. Journal Of The American Chemical Society 2015, 137: 1738-1741. PMID: 25629446, PMCID: PMC4607046, DOI: 10.1021/jacs.5b00056.Peer-Reviewed Original Research
2012
A Putative P-Type ATPase Required for Virulence and Resistance to Haem Toxicity in Listeria monocytogenes
McLaughlin H, Xiao Q, Rea R, Pi H, Casey P, Darby T, Charbit A, Sleator R, Joyce S, Cowart R, Hill C, Klebba P, Gahan C. A Putative P-Type ATPase Required for Virulence and Resistance to Haem Toxicity in Listeria monocytogenes. PLOS ONE 2012, 7: e30928. PMID: 22363518, PMCID: PMC3283593, DOI: 10.1371/journal.pone.0030928.Peer-Reviewed Original ResearchMeSH KeywordsAdenosine TriphosphatasesAnimalsBacterial ProteinsBase SequenceBiological AssayComputational BiologyDrug Resistance, BacterialGene Expression Regulation, BacterialGenes, BacterialGenetic LociHemeHomeostasisIronListeria monocytogenesListeriosisMiceMolecular Sequence DataMothsMutagenesis, InsertionalMutationPlasmidsReal-Time Polymerase Chain ReactionRepressor ProteinsVirulenceConceptsPutative P-type ATPaseFerric uptake regulatorUptake of haemIntracellular pathogen Listeria monocytogenesWax moth Galleria mellonellaP-type ATPaseAcquisition of ironPathogen Listeria monocytogenesMoth Galleria mellonellaIron-deficient mediumMembrane proteinsMutantsHaem toxicityFree haemAlternative infection modelGalleria mellonellaIron homeostasisInhibition of growthFrvAVirulenceListeria monocytogenesHaemVirulence potentialFurDeficient medium
2011
Sortase independent and dependent systems for acquisition of haem and haemoglobin in Listeria monocytogenes
Xiao Q, Jiang X, Moore K, Shao Y, Pi H, Dubail I, Charbit A, Newton S, Klebba P. Sortase independent and dependent systems for acquisition of haem and haemoglobin in Listeria monocytogenes. Molecular Microbiology 2011, 80: 1581-1597. PMID: 21545655, PMCID: PMC3115469, DOI: 10.1111/j.1365-2958.2011.07667.x.Peer-Reviewed Original Research