Purification and characterisation of haemagglutinin from Bordetella bronchiseptica

A surface protein of Bordetella bronchiseptica was purified in one step by affinity chromatography with bovine submaxillary mucin coupled to agarose. The purified protein, with a mol. wt of 200 kDa and an iso-electric point of pI 6·5, showed haemagglutinating activity for bovine erythrocytes. The haemagglutinin (HA) inhibited the adherence of B. bronchiseptica to a rat lung cell line (L2) and was able to bind to N-acetylneuraminic acid. These findings suggest that the HA of B. bronchiseptica is an adhesin.