Adenovirus Proteins II. N-Terminal Amino Acid Analysis

Adenovirus types 2, 4, 5, 6, 18, 21 and 27, were analyzed for N-terminal amino acids by use of (35)S-labeled phenylisothiocyanate of high specific radioactivity. Two free N-terminal amino acids, alanine and glycine, were found in these viruses in the molar ratio (alanine-glycine) of 2.5:1, with the exception of type 2 where the ratio was 3.6:1 and type 5 where the ratio was 5.5:1 Adenovirus type 2 was disrupted by acetone treatment, and two protein fractions were obtained after sucrose gradient centrifugation. One of these fractions, which was associated with the viral deoxyribonucleic acid and comprised approximately 18% of the total protein of the virus, was greatly enriched with respect to N-terminal alanine and glycine.