Tryptic fingerprint analysis of adenovirus types 2, 5 and 12 DNA-binding proteins

Abstract

Each of types 2, 5 and 12 human adenovirus (Ad) induces the synthesis of single-strand-specific DNA-binding proteins at early times after infection of human or monkey cells. The molecular weights of these proteins are: Ad2, 72,000; Ad5, 72,000; and Ad12, 58,000. In addition, each of these viruses produces a collection of two or three lower molecular weight (41,000–47,000), single-strand-specific DNA-binding proteins that appear in variable amounts after infection. Tryptic fingerprints of the peptides derived from [ 35S]methionine-labeled 72,000-MW (Ad2 and 5), 58,000-MW (Ad12) and 41,000–47,000-MW (Ad2, 5 and 12) DNA-binding proteins have been obtained. The results of this analysis permit the following conclusions: (i) The 72,000-MW (Ad2 and 5) and 58,000-MW (Ad12) proteins synthesized in adenovirus-infected cells are distinct from a 72,000-MW cellular DNA-binding protein found in uninfected or mock-infected cells. (ii) The [ 35S]methionine-labeled peptides derived from the 41,000–47,000-MW proteins (Ad2, 5 and 12) are similar if not identical to the [ 35S]methionine-labeled tryptic peptides derived from the larger (Ad2 and 5, 72,000-MW; Ad12, 58,000-MW) DNA-binding proteins. (iii) The [ 35S]methionine-labeled peptides derived from the adenovirus types 2 and 5, 72,000-MW proteins are quite similar but distinct from the adenovirus type 12, 58,000-MW protein. (iv) The peptide fingerprints of the adenovirus type 2, 72,000-MW protein synthesized in either human or monkey cells are very similar or identical.