Characterization of B278, a phage different from Mu that also produces auxotrophic mutations in Escherichia coli K12

Bacteriophage B278 has been characterized and compared with Mu, the only phage known to produce random mutations in E. coli. Although both phages are morphologically indistinguishable and have a similar host range, they clearly differ at both the protein and the DNA level. B278 apparently possesses a DNA protection mechanism that is different from the mom system described for Mu.