The group-specific antigen and other structural proteins of hamster and mouse C-type viruses

Abstract

The major group-specific antigen of hamster C-type viruses was purified by isoelectric focusing and used to prepare specific antibody in guinea pigs. The isoelectric point of this antigen was 6.9. The patterns of hamster and mouse virus polypeptides in SDS-polyacrylamide gels were similar and showed three major components ranging from 13,000 to 35,000 in molecular weight. The group-specific protein was eluted from SDS-polyacrylamide gels in antigenically active form and was found to correspond to the third fastest migrating component for each virus; molecular weight calculations relative to standards gave average values of 31,000 for the mouse protein and 35,000 for the hamster protein. These slight differences were maintained in coelectrophoresis experiments as were the differences for the second fastest migrating component, 17,500 for the mouse virus, 23,000 for the hamster virus. The fastest migrating polypeptides had molecular weights of 13,500–14,000 for each virus. The major gs antigens of hamster and mouse viruses did not cross-react in complement-fixation and gel diffusion tests when tested with their respective monospecific guinea pig antisera.