Identification of a Streptococcus sanguis receptor for salivary agglutinins.
The objective of this study was to characterize a fraction from oral streptococci containing receptor activity for salivary agglutinin molecules. Several species and strains of streptococci were disrupted in a Ribi press. The supernatant was nuclease-treated and subjected to differential centrifugation. Receptor activity in the fractions was measured by the inhibition of saliva-mediated bacterial aggregation. In addition, bacterial strains were tested for their ability to aggregate and to deplete saliva of agglutinin activity. Three patterns of activity were observed: Streptococcus sanguis M5 depleted saliva of agglutinin activity and aggregated well; Streptococcus sanguis CC5A depleted saliva of agglutinin but did not aggregate well; and Streptococcus faecalis S-161 neither depleted saliva of agglutinin nor did it aggregate. The 105,000 g supernatant fractions derived from Ribi-disrupted Streptococcus sanguis M5 and CC5A, but not from Streptococcus faecalis, showed dose-dependent inhibition of saliva-mediated aggregation. This inhibitory activity was non-dialyzable, had the same heat and trypsin sensitivity as that seen with intact bacteria, and was not due to enzymatic digestion of the salivary agglutinin. Iso-electric focusing revealed a single active region with a pI of 5.5 which was clearly separated from the bulk of the bacterial proteins.
Robinovitch
M R
MR
Malamud
D
D
Rosan
B
B
Golub
E E
EE
Lancy
P
P
D000371:Agglutination / Q000187:drug effects; D000373:Agglutinins / Q000378:metabolism*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003378:Counterimmunoelectrophoresis; D013293:Enterococcus faecalis / Q000276:immunology; D006358:Hot Temperature; D006801:Humans; D007525:Isoelectric Focusing; D011971:Receptors, Immunologic / Q000302:isolation & purification*; D012463:Saliva / Q000276:immunology*; D013298:Streptococcus sanguis / Q000276:immunology*; D013936:Thymidine; D014316:Tritium; D014357:Trypsin / Q000494:pharmacology
D000373:Agglutinins; D011971:Receptors, Immunologic; D014316:Tritium; D014357:Trypsin; D013936:Thymidine