The intermolecular disulfide bonds of the surface polypeptides in the infectious laryngotracheitis virus of hens

The envelope proteins of chicken infectious laryngotracheitis virus were investigated using immunoblotting, radioimmuno-precipitation, and diagonal SDS-PAGE. Polypeptides with molecular weights of 205, 155, 115, 90, and 60 kDa were detected by rabbit antiserum and those of 205, 115, 90, and 60 kDa by chicken antiserum. When chicken antiserum was used, the 60 kDa polypeptide appeared to be the major immunogen. The 60 kDa polypeptide was shown to be a disulfide linked dimer with a molecular weight of 112 kDa. It is suggested that 60 kDa polypeptide is present in virions both in dimer (112 kDa) and monomer (60 kDa) forms.