Physicochemical properties of transmissible gastroenteritis virus hemagglutinin

Transmissible gastroenteritis virus was readily adsorbed onto chicken erythrocytes at 4°C. The hemagglutinin thus adsorbed could be eluted from the erythrocytes by incubating in phosphate buffered saline at 37°C. The on chicken erythrocytes for the hemagglutinin was inactivated by neuraminidase and potassium periodate, but not by trypsin, 2-mercaptoethanol and formalin. The hemagglutinin was inactivated by trypsin, papain, pepsin, α-amylase, phospholipase C, neuraminidase, formalin, 2-mercaptoethanol, potassium periodate, ethylether, chloroform, Tween-80 and β-propiolactone, but not by sodium deoxycholate and trichlorotrifluoroethane, suggesting that the active component of the hemagglutinin involved glycoproteins. The hemagglutinin was stable at 37°C or lower temperatures but not at 60°C or higher temperatures. The hemagglutinin activity was resistant to ultraviolet irradiation, while the infectivity was very susceptible. The hemagglutinin and the infectivity were readily sedimented by ultracentrifugation at 45,000 × g for 60 minutes. In rate zonal centrifugation of the hemagglutinin preparation on a sucrose density gradient, the hemagglutinin activity showed a sharp peak at 1.19 g/ml coinciding with the peak of infectivity. The activity in the peak fraction seemed to be structually associated with virus particles.