2020
Applying Live Cell Imaging and Cryo-Electron Tomography to Resolve Spatiotemporal Features of the Legionella pneumophila Dot/Icm Secretion System.
Chetrit D, Park D, Hu B, Liu J, Roy CR. Applying Live Cell Imaging and Cryo-Electron Tomography to Resolve Spatiotemporal Features of the Legionella pneumophila Dot/Icm Secretion System. Journal Of Visualized Experiments 2020 PMID: 32225141, DOI: 10.3791/60693.Peer-Reviewed Original ResearchConceptsDot/Icm secretion systemCryo-electron tomographySecretion systemCryo-ETDot/Icm systemDot/Icm apparatusDot/IcmSuperfolder green fluorescent proteinLive-cell imagingGreen fluorescent proteinIntact bacterial cellsPolar positioningSecretion complexPolar localizationQuantitative fluorescence microscopyBacterial poleATPase geneCytoplasmic complexDelivery of proteinsDNA substratesTiming of productionIcm systemFluorescent proteinLiving cellsBacterial cellsAnalysis of Dot/Icm Type IVB Secretion System Subassemblies by Cryoelectron Tomography Reveals Conformational Changes Induced by DotB Binding
Park D, Chetrit D, Hu B, Roy CR, Liu J. Analysis of Dot/Icm Type IVB Secretion System Subassemblies by Cryoelectron Tomography Reveals Conformational Changes Induced by DotB Binding. MBio 2020, 11: 10.1128/mbio.03328-19. PMID: 32071271, PMCID: PMC7029142, DOI: 10.1128/mbio.03328-19.Peer-Reviewed Original ResearchConceptsType IV secretion systemSecretion systemCryoelectron tomographyInner membraneDot/Icm apparatusConformational changesDot/IcmEukaryotic host cellsBacterial inner membraneWild-type cellsHost cell membraneWhole-cell contextMultiprotein nanomachineSubtomogram analysisSophisticated nanomachinesCytoplasmic substratesProtein effectorsCell polesDNA substratesSubtomogram averagingATPase complexDNA transferHost infectionStructural basisHost cells
2018
A unique cytoplasmic ATPase complex defines the Legionella pneumophila type IV secretion channel
Chetrit D, Hu B, Christie PJ, Roy CR, Liu J. A unique cytoplasmic ATPase complex defines the Legionella pneumophila type IV secretion channel. Nature Microbiology 2018, 3: 678-686. PMID: 29784975, PMCID: PMC5970066, DOI: 10.1038/s41564-018-0165-z.Peer-Reviewed Original ResearchConceptsCytoplasmic complexType IV secretion channelType IV secretion systemInner membrane complexTranslocation of substratesCryo-electron tomographySecretion channelCell polesCytoplasmic ATPaseSecretion systemT4SS functionHexameric assemblyMembrane complexCytoplasmic channelsDNA complexesSubstrate transferT4SSChannel activationATPaseComplexesDistinct stagesAssemblyBiogenesisATPasesFurther analysis