title: Quantitative Proteomics Reveals the Dynamics of Protein Phosphorylation in Human Bronchial Epithelial Cells during Internalization, Phagosomal Escape, and Intracellular Replication of Staphylococcus aureus.
abstract: Internalization of Staphylococcus aureus by nonprofessional phagocytic cells is a major suspected cause of persistent and difficult-to-treat infections, including pneumonia. In this study, we established an infection model with 16HBE14o- human bronchial epithelial cells and demonstrated internalization, escape from phagosomal clearance, and intracellular replication of S. aureus HG001 within the first 4 h postinfection. We used quantitative phosphoproteomics to identify characteristic signaling networks in the host at different infection stages. Although we found only minor changes in protein abundance, the infection was accompanied by highly dynamic alterations in phosphorylation events primarily in proteins that are associated with pathways of cytoskeleton dynamics, cell-cell and cell-matrix contacts, vesicle trafficking, autophagy, and GTPase signaling. Analyses of host protein kinases by kinase-substrate mapping, active regulatory site immunoblotting, and prediction algorithms highlighted known and novel host kinases with putative critical roles in S. aureus infection-accompanied signaling including FAK, PKA, PKC, and CDK. Targeted pharmacological inhibition of these kinases resulted in a significant reduction of intracellular S. aureus cells. The current study constitutes a valuable resource for better understanding the infection-relevant molecular pathomechanisms of airway cells and for developing novel host-centric anti-infective strategies for treating S. aureus infections.
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Richter
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Manuela
authors.initials: M
authors.lastname: Harms
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Ventz
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Nölker
authors.affiliation: Department of Microbiology, University of Würzburg , 97074 Würzburg, Germany.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Fraunholz
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Mostertz
authors.affiliation: Competence Center Functional Genomics, Junior Research Group Pathoproteomics, University of Greifswald , 17489 Greifswald, Germany.
authors.forename: Falko
authors.initials: F
authors.lastname: Hochgräfe
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis; D001980:Bronchi / Q000166:cytology / Q000382:microbiology; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000378:metabolism / Q000382:microbiology; D054884:Host-Pathogen Interactions; D006801:Humans; D007239:Infections; D010766:Phosphorylation; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D013211:Staphylococcus aureus / Q000737:chemistry / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D020543:Proteome
keywords: 16HBE14o-human bronchial epithelial cells; S. aureus infection; airway epithelium; host signaling; host-directed therapy; phosphoproteomics