Changes of adenovirus hexon associated with different passage history of Ad h 1

Two descendants of the prototype strain AD71-Washington D. C. were obtained by independent passaging for at least 18 years in Kiev, and in Budapest (Ad h 1 kappa, and Ad h 1B, respectively). By restriction endonuclease mapping, the DNA was identical corresponding to the patterns of human adenovirus type 1. In spite of this, SDS-polyacrylamide gel electrophoresis revealed that the purified hexon of Ad h 1 kappa was of lower Mr than the subunit of Ad h 1B. In contrast to this, the native capsomer (hexon) of Ad h 1 kappa exhibited lower electrophoretic mobility in agarose gel electrophoresis than the native hexon of Ad h 1B. Oligopeptide mapping of the main hexon bands from SDS-polyacrylamide gels revealed the presence of unique spots among the chymotryptic oligopeptides of Ad h 1B, too. Thus, the differences in the sensitivity to proteolytic cleavage during purification seem to have a structural basis. Antigenic analysis of the native hexon capsomers was performed using polyclonal antihexon immunsera. Immunodiffusion, immunoelectrophoresis, and competitive RIA were used for comparison. The results indicate that native hexon capsomers of Ad h 1 kappa and Ad ha 1B possess antigenic differences within the type-specific regions, nevertheless, their genetic background could not be detected by the restriction endonucleases applied. It cannot be excluded that the differences were results of altered assembly of virions under different passage conditions.