Structural analysis of the actinophage phi C31 attachment site.

The lysogenisation of actinophage phi C31 in S. coelicolor J 1501 occurs by site-specific recombination. The DNA segments containing the attachment sites on the host chromosome, the phage genome and the two junctions created by the insertion of the prophage were cloned and the nucleotide sequences determined. The attachment sites (att) share an extremely short common sequence of three base pairs. Adjacent to the core sequences some direct- and inverted repeats were found as potential binding sites for proteins involved in site-specific recombination.