The infectivity of suspensions of foot-and-mouth disease virus is greatly reduced by incubation with trypsin. Preliminary studies with unfractionated suspensions suggested that the viral RNA was not involved in the inactivation because the infectivity of the RNA extracted with phenol from the enzyme-treated suspensions was as high as that from the untreated virus (1). The reduction in infectivity was probably due to the failure of the virus to adsorb to the susceptible cells. This report describes a more detailed investigation of the mode of inactivation, using purified virus labelled with P- or C.

Virus of type 0 was grown in BHK21 cells (2) using a phosphate-low medium containing 1 µg. actinomycin D/ml. and labelled with C, or Earle's saline containing protein hydrolysate phosphate labelled with P. The virus was purified by the method described by Brown & Cartwright (3). In a typical experiment with P-labelled virus, the infectivity was reduced from 6·3 × 10 plaque forming units (p.f.u.)/ml. to 1·8 × 10p.f.u./ml. by incubation with 1 mg. trypsin/ml. for 15 min. at 37°.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error