CONSTRUCTION OF A CIRCULAR CHROMOSOMAL GE NETIC-MAP OF AGROBACTERIUM-RADIOBACTER - LOCALIZATION OF NITROGEN-METABOLISM GENES

The possibilities for localizing chromosomal loci of F+ and Hfr-type d onors and various methods of evaluating gene linkage were tested in th e saprophyte Agrobacterium radiobacter 5D-1 strain, which has associat ive interrelations with plants and produces indoleacetic acid. It was shown that the definition of gene linkage with the proximal marker in matings with Hfr-type donors is the most suitable method for construct ing a genetic map. A circular genetic map of the chromosome of A. radi obacter was constructed, and 22 mutations, responsible for auxotrophy, resistance to chloramphenicol and gentamycin, and nitrogen metabolism alterations, were localized on this map. The location regions of anot her nine genes, responsible for amino acid metabolism, the mutations i n which are mediated by the insertion of the Tn5-mob transposon, were also defined.