Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P43026 (
lipopolysaccharide
)
62,215
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Supernatants of human peripheral blood mononuclear cells cultured in the presence of B. gingivalis, showed a strong osteoclast stimulating activity as measured by 45Ca release from fetal mouse long bones in vitro. These supernatants also contained a high concentration of bioactive and immunoreactive interleukin-1 (IL-1), but tumor necrosis factor (TNFa), another osteoclast-activating cytokine, was not detected. Osteoclast activation by the supernatants was inhibited by an antibody against IL-1, whereas ultrapure human IL-1 mimicked the effect of the supernatant. The ability of B. gingivalis to induce IL-1 and
OAF
production was heat sensitive, as 20 min heating of the bacteria at 120 degrees C caused a 50% loss of activity. In addition, purified B. gingivalis
lipopolysaccharide
(
LPS
) had little IL-1 inducing capacity, compared with
LPS
of Escherichia coli. These data suggest that human peripheral blood cells confronted with B. gingivalis produce large amounts of IL-1 which has strong osteoclast stimulating activity. However, in contrast with E. coli
LPS
, B. gingivalis
LPS
does not seem to be the major inducing agent. Thus other bacterial components must be responsible for the observed IL-1 and
OAF
induction.
...
PMID:Bacteroides gingivalis stimulates bone resorption via interleukin-1 production by mononuclear cells. The relative role for B. gingivalis endotoxin. 220 3
The authors examined the ability of octadecanoyl (C(18)), hexadecanoyl (C(16)) and dodecanoyl (C(12)) fatty acid (FA) conjugates of 5-aminofluorescein (
OAF
, HAF and DAF, respectively) to insert into the outer membranes (OMs) of Treponema pallidum, Borrelia burgdorferi and Escherichia coli. Biophysical studies have demonstrated that these compounds stably insert into phospholipid bilayers with the acyl chain within the hydrophobic interior of the apical leaflet and the hydrophilic fluorescein moiety near the phospholipid head groups. Consistent with the known poor intrinsic permeability of the E. coli OM to hydrophobic compounds and surfactants, E. coli was not labelled with any of the FA probes.
OAF
inserted more readily into OMs of B. burgdorferi than into those of T. pallidum, although both organisms were completely labelled at concentrations at or below 2 microg ml(-1). Intact spirochaetes were labelled with
OAF
but not with antibodies against known periplasmic antigens, thereby confirming that the probe interacted exclusively with the spirochaetal OMs. Separate experiments in which organisms were cooled to 4 degrees C (i.e. below the OM phase-transition temperatures) indicated that labelling with
OAF
was due to insertion of the probe into the OMs. B. burgdorferi, but not T. pallidum, was labelled by relatively high concentrations of HAF and DAF. Taken as a whole, these findings support the prediction that the lack of
lipopolysaccharide
renders T. pallidum and B. burgdorferi OMs markedly more permeable to lipophilic compounds than their Gram-negative bacterial counterparts. The data also raise the intriguing possibility that these two pathogenic spirochaetes obtain long-chain FAs, nutrients they are unable to synthesize, by direct permeation of their OMs.
...
PMID:Insertion of fluorescent fatty acid probes into the outer membranes of the pathogenic spirochaetes Treponema pallidum and Borrelia burgdorferi. 1132 Jan 19