GENETIC CIRCULARITY OF THE PROTEUS-MIRABILIS LINKAGE MAP

The T incompatibility group plasmid R394 can mobilize the chromosome of P. mirabilis strain PM 5006. It transferred relatively large segments, corresponding to at least 20 min on the D plasmid chromosomal map of the organism. The frequency of recombination for a large number of selected markers was nearly constant at 5 .times. 10-6/donor cell and mobilization apparently takes place from a number of chromosomal sites. All recombinants were R+ and displayed all properties of the plasmid. By analyzing crosses for co-inheritance frequencies of unselected markers, a number of chromosomal loci were assembled in linear array. Linkage between markers at the ends of this linkage group was established to markers at the respective termini of the existing D plasmid linkage group. This established a composite circular linkage map of genes of the P. mirabilis strain PM5006 chromosome.