2023
Bacteria require phase separation for fitness in the mammalian gut
Krypotou E, Townsend G, Gao X, Tachiyama S, Liu J, Pokorzynski N, Goodman A, Groisman E. Bacteria require phase separation for fitness in the mammalian gut. Science 2023, 379: 1149-1156. PMID: 36927025, PMCID: PMC10148683, DOI: 10.1126/science.abn7229.Peer-Reviewed Original ResearchConceptsMammalian gutTranscription termination factor RhoTermination factor RhoGene regulationTranscription terminationMechanisms bacteriaBacteria interactionsHuman commensalValuable targetBacteriaRhoGut microbiotaFitnessNovel clinical applicationsTherapeutic manipulationGutHuman healthCommensalRegulationIL-22 alters gut microbiota composition and function to increase aryl hydrocarbon receptor activity in mice and humans
Mar J, Ota N, Pokorzynski N, Peng Y, Jaochico A, Sangaraju D, Skippington E, Lekkerkerker A, Rothenberg M, Tan M, Yi T, Keir M. IL-22 alters gut microbiota composition and function to increase aryl hydrocarbon receptor activity in mice and humans. Microbiome 2023, 11: 47. PMID: 36894983, PMCID: PMC9997005, DOI: 10.1186/s40168-023-01486-1.Peer-Reviewed Original ResearchConceptsIL-22 treatmentUC patientsAhR activityIL-22 productionUlcerative colitis patientsGastrointestinal barrier functionMicrobiome compositionGut microbiome compositionAryl hydrocarbon receptorColitis patientsIL-22Gastrointestinal tractHealthy volunteersFunctional capacityMucus secretionAntimicrobial protein productionMicrobiota compositionEpithelial cell differentiationFecal concentrationsReceptor activityGut microbiomePatientsAhR signalingAryl hydrocarbon receptor (AhR) activityBarrier function
2022
Host Cell Amplification of Nutritional Stress Contributes To Persistence in Chlamydia trachomatis
Pokorzynski N, Alla M, Carabeo R. Host Cell Amplification of Nutritional Stress Contributes To Persistence in Chlamydia trachomatis. MBio 2022, 13: e02719-22. PMID: 36377897, PMCID: PMC9765610, DOI: 10.1128/mbio.02719-22.Peer-Reviewed Original ResearchConceptsHost cell responsesInfected host cellsNutritional stressStress responseIntracellular environmentGTP biosynthesisHost cellsUniversal stress responseTranscriptional stress responseDual RNA sequencingConsequence of coevolutionEssential nutrient ironBacterial stress responseStress response mechanismsChlamydial growthGuanine nucleotide synthesisGenome reductionTryptophan starvationEukaryotic hostsIron starvationInfected epithelial cellsRNA sequencingNutrient ironIron limitationDistinct nutrients
2020
The iron-dependent repressor YtgR is a tryptophan-dependent attenuator of the trpRBA operon in Chlamydia trachomatis
Pokorzynski ND, Hatch ND, Ouellette SP, Carabeo RA. The iron-dependent repressor YtgR is a tryptophan-dependent attenuator of the trpRBA operon in Chlamydia trachomatis. Nature Communications 2020, 11: 6430. PMID: 33353937, PMCID: PMC7755916, DOI: 10.1038/s41467-020-20181-5.Peer-Reviewed Original ResearchConceptsIntergenic regionRho-independent transcription terminationOpen reading frameTranscription terminationYtgRAlternative promotersTrp operonOperator sequenceTryptophan limitationOperonMajor promoterModel bacteriaTrpRSPromoterMotifBacteriaExpressionChlamydia trachomatisRepressorTrpBRepressionFundamental importanceTRPLAlternative strategySequence
2017
Ironing Out the Unconventional Mechanisms of Iron Acquisition and Gene Regulation in Chlamydia
Pokorzynski ND, Thompson CC, Carabeo RA. Ironing Out the Unconventional Mechanisms of Iron Acquisition and Gene Regulation in Chlamydia. Frontiers In Cellular And Infection Microbiology 2017, 7: 394. PMID: 28951853, PMCID: PMC5599777, DOI: 10.3389/fcimb.2017.00394.Peer-Reviewed Original ResearchConceptsGene regulationIron homeostasisAberrant morphological phenotypesIron biologyUnconventional mechanismObligate intracellular pathogensDeprivation of ironSpecies relativesTranscriptional regulatorsGenome sequenceTransporter subunitsIron acquisitionIron-dependent bacteriaVesicular modeChlamydial speciesMorphological phenotypesIntracellular environmentIntracellular pathogensImportance of ironRecent discoveryAvailability of ironHomeostasisRecent findingsBiologyPersistent phenotype