@article{mbs:/content/journal/micro/10.1099/mic.0.2008/019943-0, author = "Pathirana, Rishi D. and O'Brien-Simpson, Neil M. and Visvanathan, Kumar and Hamilton, John A. and Reynolds, Eric C.", title = "The role of the RgpA–Kgp proteinase–adhesin complexes in the adherence of Porphyromonas gingivalis to fibroblasts", journal= "Microbiology", year = "2008", volume = "154", number = "10", pages = "2904-2911", doi = "https://doi.org/10.1099/mic.0.2008/019943-0", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.2008/019943-0", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", keywords = "TLCK, Nα-p-tosyl-lysine chloromethyl ketone", keywords = "PE, phycoerythrin", keywords = "BCR, bacterium to fibroblast cell ratio", keywords = "MFI, mean fluorescence intensity", abstract = " Porphyromonas gingivalis strains W50 and ATCC 33277 were shown to bind to cultured human fibroblast (MRC-5) cells using flow cytometry. As the concentration of P. gingivalis strain W50 cells was increased relative to the concentration of MRC-5 cells, the number of W50 cells bound per MRC-5 cell increased, as did the percentage of MRC-5 cells with bacteria bound. However, this relationship was only seen for P. gingivalis strain ATCC 33277 at low cell concentrations: at high bacterial cell concentrations strain ATCC 33277 auto-aggregated and binding to the MRC-5 cells decreased. Strain W50 was therefore chosen to study the role of the surface proteinase–adhesin complexes (RgpA–Kgp complexes) in binding to MRC-5 cells. P. gingivalis W50 cells treated with an inhibitor of the RgpA–Kgp complexes exhibited reduced binding to MRC-5 cells. The purified active and proteinase-inactive RgpA–Kgp complexes competitively inhibited binding of W50 to MRC-5 cells, and isogenic mutants of W50 lacking RgpA/B and Kgp displayed reduced binding. P. gingivalis W50 mutant cells lacking Kgp exhibited the lowest binding to MRC-5 cells, suggesting an important role for this proteinase and its associated adhesins in binding to fibroblasts.", }