Bacteriophage S13: A Seventh Gene

Genetic complementation tests of ochre-type suppressible mutants of bacteriophage S13 have revealed a seventh gene. A mutation of this gene has no significant effect on synthesis of the phage replicative form DNA, but like five other phage genes it prevents the appearance of single-stranded DNA. With the new gene, it seems likely that approximately 70 to 100 percent of the phage genes are accounted for.