Abstract
Phage .vphi.29 DNA cannot be phosphorylated with polynucleotide kinase and [.gamma.-32P]ATP because of the presence of a viral protein covalently linked to the 5'' termini. The 5'' ends can be made susceptible to phosphorylation by treatment with alkali and alkaline phosphatase. Restriction fragments Hpa II C and Hpa II F, corresponding to the right and left ends of .vphi.29 DNA, respectively, were labeled at the 5'' ends with polynucleotide kinase and [.gamma.-32P]ATP or at the 3'' ends with terminal transferase and [.alpha.-32P]ATP or [.alpha.-32P]cordycepin 5''-triphosphate. After a secondary cleavage of the labeled fragments, the sequence of the first 150-180 nucleotides at the termini of .vphi.29 DNA was determined by the Maxam and Gilbert method. The ends of .vphi.29 DNA are flush and a 6-nucleotides-long inverted terminal repetition was found. The functional implications of the sequences determined are discussed.