Animal picornaviruses with a single major species of capsid protein

Abstract

Summary The caliciviruses—San Miguel sea lion virus (SMSV), vesicular exanthema of swine virus (VESV) and feline picornavirus (FPV)—were found by polyacrylamide gel electrophoresis to possess a single major species of capsid protein with a molecular weight of approximately 61,000 daltons. This differs from all other animal picornaviruses (cardio, entero and rhino), which have four types of proteins. The caliciviruses were also found to co-sediment as a single peak in sucrose-density gradients, and at a rate considerably faster than foot-and-mouth disease virus (FMDV), which is generally classified as a rhinovirus. Infectious ribonucleic acid could also be prepared from each of the caliciviruses, but in lower yield than from FMDV. These results lend support to the theory that VESV originated from SMSV.