Isolation, Characterization, and Classification of Additional Bacteriophages for the Genus Levinea

Additional bacteriophages were obtained from pooled sewage samples for the genus Levinea. On the basis of plaque morphology and host specificity, three different phages were isolated and purified by serial single-plaque isolations. Cross-neutralization tests were performed on each of the new phage isolates as well as on three previously reported Levinea phages using homologous and heterologous antisera. The data indicated no serological relatedness among the six phages and, therefore, three additional serological groups were established. The phages were designated DM-41, DM-51, and DM-61. Electron micrographs revealed that DM-41 and DM-51 possess a contractile tail whereas DM-61 has a short, noncontractile tail. The phages contained double-stranded deoxyribonucleic acid as determined by the acridine orange-fluorescent staining technique. The value of the phages for use in defining Levinea species and determining relatedness between levineae and the genus Citrobacter is discussed.