The effect of the outer membrane fraction of Bacteroides gingivalis W50 on glycosaminoglycan metabolism by human gingival fibroblasts in culture.
The synthesis of extracellular [35S]-SO4- and [3H]-glucosamine-labelled glycosaminoglycan (GAG) was studied in confluent human gingival fibroblast cultures in vitro. The differential synthesis of the total chondroitin sulphate/dermatan sulphate (CS/DS) and heparan-sulphate (HS) fraction was measured following chondroitinase-ABC digestion, nitrous-acid treatment and column chromatography on Sephadex G50. Control cultures synthesized a CS/DS fraction that represented 78 per cent of the total [35S]-SO4-GAG; the residual 22 per cent was heparan sulphate. Similar cultures were labelled with [3H]-glucosamine and the proportions of a high molecular-weight hyaluronic acid (HA) and proteoglycan fractions measured by gel-filtration HPLC after papain and hyaluronidase digestions. The HA fraction represented 66 per cent of the total isotope incorporated in control cultures. GAG chains released on treatment with papain (24 per cent of the total label incorporated) were of apparent molecular weight 17-20 kDa. All cultures exposed to Bacteroides gingivalis W50 outer membrane at concentrations between 2 and 50 micrograms ml-1 displayed a decrease in the CS/DS fraction and a reciprocal increase in the HS. However, the proportion of HA synthesized was slightly enhanced with a reciprocal decrease in the proteoglycan (papain-digestible) fraction. There was no alteration in the molecular weight of the papain-digestion products or the size distribution of the hyaluronic-acid fraction.
Smalley
J W
JW
Department of Dental Sciences, University of Liverpool, England, U.K.
Birss
A J
AJ
Shuttleworth
C A
CA
D001425:Bacterial Outer Membrane Proteins / Q000494:pharmacology*; D001439:Bacteroides; D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D005881:Gingiva / Q000187:drug effects / Q000378:metabolism*; D006025:Glycosaminoglycans / Q000378:metabolism*; D006801:Humans
D001425:Bacterial Outer Membrane Proteins; D006025:Glycosaminoglycans