Separation and structural analysis of lipoprotein in a lipopolysaccharide preparation from Porphyromonas gingivalis.
Lipopolysaccharide (LPS) preparations from the periodontopathic bacterium Porphyromonas gingivalis (Pg-LPS) are thought to require Toll-like receptor (TLR)2 rather than TLR4, a receptor of Escherichia coli LPS (Ec-LPS), for activation of immune cells. However, we previously reported that P. gingivalis lipid A, an immunostimulatory principal component of LPS, and its synthetic counterpart activate cells through a TLR4-dependent pathway but not via TLR2. In the present study, a lipoprotein from Pg-LPS (Pg-LP) was shown to be a principal component for TLR2-mediated cell activation. Pg-LP was separated by hydrophobic interaction chromatography followed by preparative electrophoresis and identified by internal peptide sequencing as PG1828, a putative lipoprotein encoded in the P. gingivalis genome. The N-terminal structure was characterized as a triacylated lipopeptide using mass spectrometry. Pg-LP, as well as Ec-LPS, was potent in inducing IL-8 production in human gingival fibroblasts. From our results, we propose that Pg-LP is a powerful inflammatory factor of P. gingivalis.
Department of Oral Microbiology, Asahi University School of Dentistry, 1851-1 Hozumi, Mizuho, Gifu 501-0296, Japan.
Masahito
M
Hashimoto
Yasuyuki
Y
Asai
Tomohiko
T
Ogawa
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005347:Fibroblasts / Q000187:drug effects / Q000276:immunology; D006801:Humans; D008070:Lipopolysaccharides / Q000032:analysis*; D008074:Lipoproteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology*; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000276:immunology / Q000378:metabolism; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000737:chemistry / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000276:immunology*; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors
D008070:Lipopolysaccharides; D008074:Lipoproteins; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors