@article{mbs:/content/journal/micro/10.1099/00221287-137-6-1285, author = "Shearman, C. A. and Hertwig, S. and Teuber, M. and Gasson, M. J.", title = "Characterization of the prolate-headed lactococcal bacteriophage ϕvML3: location of the lysin gene and its DNA homology with other prolate-headed phages", journal= "Microbiology", year = "1991", volume = "137", number = "6", pages = "1285-1291", doi = "https://doi.org/10.1099/00221287-137-6-1285", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-137-6-1285", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "Summary: ϕvML3 is a virulent prolate-headed bacteriophage that attacks a genetically well-studied strain family including Lactococcus lactis subsp. lactis strains 712, C2 and ML3. A restriction map was constructed for ϕvML3 using a wide variety of restriction endonucleases. The DNA was highly refractory to in vitro restriction; this is a common feature of lytic lactococcal phages. Genome size was estimated as 23 kb, which is similar to the sizes of other phages of the same morphological group. The presence of heat-dissociable DNA fragments was noted in gel electrophoresis of restriction enzyme digests. Cohesive ends were confirmed by pretreating the DNA with T4 ligase, which rendered the composite fragment insensitive to heat. The phage ϕvML3 genome thus consists of linear and non-permuted double-stranded DNA with complementary cohesive ends. The lysin gene from this phage acts as a specific lysis agent against the lactic streptococci. This gene has been cloned and sequenced previously. Further specific subcloning of EcoRV fragments of ϕvML3 DNA has located the lysin gene in the central region of the genome, orientated from right to left. This location was confirmed by hybridization of a lysin gene probe to ϕvML3 DNA. The lysin gene probe showed homology to a number of other prolate-headed phages including P001. The lysin gene of P001 was shown to be located in the central region of its genome. However, the isometric phage P107 did not hybridize, in spite of encoding its own lysin gene.", }