The N-terminal lipopeptide of a 44-kDa membrane-bound lipoprotein of Mycoplasma salivarium is responsible for the expression of intercellular adhesion molecule-1 on the cell surface of normal human gingival fibroblasts.
The activities to induce TNF-alpha production by a monocytic cell line, THP-1, and ICAM-1 expression and IL-6 production by human gingival fibroblasts were detected in plural membrane lipoproteins of Mycoplasma salivarium. Although SDS-PAGE of the lipoproteins digested by proteinase K did not reveal any protein bands with molecular masses higher than approximately10 kDa, these activities were detected in the front of the gel. A lipoprotein with a molecular mass of 44 kDa (Lp44) was purified. Proteinase K did not affect the ICAM-1 expression-inducing activity of Lp44, but lipoprotein lipase abrogated the activity. These results suggested that the proteinase K-resistant and low molecular mass entity, possibly the N-terminal lipid moiety, played a key role in the expression of the activity. The N-terminal lipid moiety of Lp44 was purified from Lp44 digested with proteinase K by HPLC. Judging from the structure of microbial lipopeptides as well as the amino acid sequence and infrared spectrum of Lp44, the structure of the N-terminal lipid moiety of Lp44 was speculated to be S-(2, 3-bisacyloxypropyl)-cysteine-GDPKHPKSFTEWV-. Its analogue, S-(2, 3-bispalmitoyloxypropyl)-cysteine-GDPKHPKSF, was synthesized. The lipopeptide was similar to the N-terminal lipid moiety of Lp44 in the infrared spectrum and the ICAM-1 expression-inducing activity. Thus, this study suggested that the active entity of Lp44 was its N-terminal lipopeptide moiety, the structure of which was very similar to S-(2, 3-bispalmitoyloxypropyl)-cysteine-GDPKHPKSF.
Shibata
K
K
Department of Oral Bacteriology, Hokkaido University School of Dentistry, Sapporo, Japan. shibaken@den.hokudai.ac.jp
Hasebe
A
A
Into
T
T
Yamada
M
M
Watanabe
T
T
D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D005347:Fibroblasts / Q000276:immunology / Q000378:metabolism*; D005881:Gingiva / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D055666:Lipopeptides; D008074:Lipoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009174:Mycoplasma / Q000737:chemistry / Q000276:immunology*; D009842:Oligopeptides / Q000737:chemistry; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*
D001425:Bacterial Outer Membrane Proteins; D016207:Cytokines; D055666:Lipopeptides; D008074:Lipoproteins; C417669:Lp44 lipopeptide; D009842:Oligopeptides; D010446:Peptide Fragments; D018799:Intercellular Adhesion Molecule-1; C106335:macrophage stimulatory lipopeptide 2