A physical-genetic map of the lipid-containing bacteriophage PR4

A physical map of the bacteriophage PR4 genome was constructed which includes 59 sites for 10 restriction endonucleases. The average size of the phage PR4 genome estimated from the sum of DNA fragments generated with the restriction endonucleases HphI, MnlI, BglI, AlwNI, and BstXI is 15, 170 ± 240 bp. A collection of recombinant plasmids containing restriction fragments of PR4 DNA generated with BglI, HphI, MnlI, and XmnI inserted into either the low copy number plasmid vector pHSG575 or the high copy number plasmid vector pUC19 was constructed. This collection of recombinant plasmids represents roughly 93% of the PR4 genome. We also constructed a bank of 136 recombinant plasmids containing PR4 DNA fragments resulting from HpaII partial digestion. We have localized 13 genes on the phage PR4 genome through marker rescue with these phage DNA clones. These genes include the structural genes for the major capsid protein (P2) and a nonstructural protein (P6A) implicated in virus assembly.