Dynamic relocalization of phage phi 29 DNA during replication and the roleof the viral protein p16.7

We have examined the localization of DNA replication of the Bacillus subtil is phage phi 29 by immunofluorescence. To determine where phage replication was localized within infected cells, we examined the distribution of phage replication proteins and the sites of incorporation of nucleotide analogue s into phage DNA. On initiation of replication, the phage DNA localized to a single focus within the cell, nearly always towards one end of the host c ell nucleoid. At later stages of the infection cycle, phage replication was found to have redistributed to multiple sites around the periphery of the nucleoid, just under the cell membrane. Towards the end of the cycle, phage DNA was once again redistributed to become located within the bulk of the nucleoid. Efficient redistribution of replicating phage DNA from the initia l replication site to various sites surrounding the nucleoid was found to b e dependent on the phage protein p16.7.