The influence of the host cell, ionic strength and chymotrypsin on foot-and-mouth disease virus electrophoretic mobility

Summary

Cellulose acetate zone electrophoretic analyses of foot-and-mouth disease virus (FMDV), type A, strain 119, with different passage histories revealed differences in homogeneity and response to chymotrypsin induced mobility changes. Foot-and-mouth disease virus with a high passage history in calf kidney cells migrated as a single electrophoretic component at the pH and ionic strengths examined. This virus, purified after a single additional passage in baby hamster kidney cells, clone 13, also gave a single zone. In contrast, virus purified after a single passage in uncloned baby hamster kidney cells revealed two electrophoretic zones, 1 and 2, as determined by staining and infectivity. Zone 1 migrated the same distance as the single virus zone prepared from the high passage calf kidney cells. All FMDV with low passage histories had only a single electrophoretic zone.

After incubation with chymotrypsin, differences between FMDV with low and high passage histories were indicated by the increase in mobility of only high passage virus. It was further demonstrated that only the mobility of zone 1 of the heterogeneous virus was changed by the enzyme. Trypsin, ribonuclease, and diisopropylfluorophosphate inactivated chymotrypsin had no effect.