title: Agglutination of human erythrocytes by Fusobacterium nucleatum: factors influencing hemagglutination and some characteristics of the agglutinin.
abstract: Various aspects of agglutination of human erythrocytes by fusobacterium nucleatum were examined. Titration experiments done in buffered saline at pH 6 to 10 showed the same agglutination endpoint. The presence of high concentrations of NaCl in reaction mixtures did not alter titers, but KCl in concentrations of 0.5 to 3.6 M increased titers twofold. The agglutinin was inactivated by heat, acid, alkali, 5% Formalin, and the proteolytic enzyme subtilopeptidase A and therefore appeared to be a protein. Treatment of bacterial cells with 2-mercaptoethanol had no effect. Hemagglutination inhibition experiments revealed that arginine and other compounds containing a guanido group as part of their structure were inhibitory at low concentrations. Various hexoses, some hexose derivatives, and most common metal ions, when added to bacterium-erythrocyte mixtures, had no effect. The binding of dansyl-L-arginine to bacteria, but not erythrocytes, was demonstrable by ultraviolet fluorescence microscopy.
mesh_terms: D000373:Agglutinins / Q000032:analysis*; D000596:Amino Acids / Q000494:pharmacology; D001120:Arginine / Q000378:metabolism; D002241:Carbohydrates / Q000494:pharmacology; D005673:Fusobacterium / Q000276:immunology*; D006384:Hemagglutination / Q000187:drug effects; D006388:Hemagglutinins / Q000032:analysis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000494:pharmacology; D009994:Osmolar Concentration; D010447:Peptide Hydrolases / Q000494:pharmacology; D013696:Temperature
chemical_list: D000373:Agglutinins; D000596:Amino Acids; D002241:Carbohydrates; D006388:Hemagglutinins; D008670:Metals; D001120:Arginine; D010447:Peptide Hydrolases