Properties of the transducing phage Ml of Rhizobium meliloti


  • Wanda Malek

    Corresponding author
    1. Department of General Microbiology, Institute of Microbiology, M.-Curie-Sklodowska University, 20–033 Lublin, Poland
    • Department of General Microbiology, Institute of Microbiology, M. Curie-Sklodowska University, Akademicka 19, 20–033 Lublin, Poland
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A temperate phage Ml, infective towards some R. meliloti strains, was isolated from soil taken from local fields. Its morphology, host range, transducing ability and the locations of restriction endonuclease cleavage sites on the genomes were determined. Phage Ml was classified as belonging to B BRADLEY's group bacteriophages because of the hexagonal outlines of its head and its long, flexible and non-contractible tail. The molecular weight of phage DNA was estimated to be 54.1 ± 1 kilobases (kb) and it corresponded to the value expected for capsid size – 70 nm. Phage Ml carries out general transduction and forms stable lysogens with the R. meliloti strain L5.30.