Glucan-binding factor in saliva.
High-molecular-weight polymers of alpha-1,6-linked D-glucans are insoluble in alcohol solutions. Whole, but not parotid, saliva prevented the precipitation of D-glucans by 80% (vol/vol) ethanol, showing that the whole saliva contained a factor which complexed with the glucan to render it alcohol soluble. The glucan-binding factor was retained on a column of Sephacryl S-200 which had been preequilibrated with 80% ethanol. The factor was then eluted with water. Passive hemagglutination assays revealed that the glucan-binding factor could sensitize erythrocytes to agglutination with anti-poly(glycerolphosphate), suggesting that the active glucan-binding component with lipoteichoic acid. The glucan-solubilizing factor was resistant to heat (100 degrees C), proteases, sialidase, lysozyme, lactoperoxidase, trichloroacetic acid, and Triton X-100. When sucrose was added to saliva, a suspension of Streptococcus cricetus AHT, or a suspension of Streptococcus sanguis 10556, relatively large amounts of glucan-binding factor were released in a soluble form. In addition, penicillin G caused the release of the glucan-solubilizing component from a suspension of S. cricetus AHT. It is suggested that whole saliva contains a component, tentatively identified as lipoteichoic acid, which can complex with glucans in a relatively hydrophobic solvent. This type of complex formation may be important in the adhesion of oral streptococci to saliva-coated surfaces.
Cowan
M M
MM
Health Sciences Center, University of Louisville, Kentucky 40292.
Parrish
K
K
Kessler
R E
RE
Pyle
C
C
Taylor
K G
KG
Ciardi
J E
JE
Doyle
R J
RJ
D005936:Glucans / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism; D012463:Saliva / Q000032:analysis* / Q000382:microbiology; D012995:Solubility; D013291:Streptococcus / Q000502:physiology; D013682:Teichoic Acids / Q000378:metabolism
D005936:Glucans; D008070:Lipopolysaccharides; D013682:Teichoic Acids; C009900:lipoteichoic acid