Abstract
The mobilized symbiotic plasmid (pRt4Sa::Tn5-mob, 315 kb) of Rhizobium leguminosarum bv. trifolii 4S was transferred into Agrobacterium tumefaciens A136 (pTi cured derivative strain C58), by conjugation technique. Most of transconjugants formed noneffective nodules on white clover. Many transconjugants confirmed pRt4Sa as plasmid form, though one strain Afcs1 could not comfirmed it.
To determine the integration site of pRt4Sa::Tn5-mob in the strain Afcs1, Pulsed-Field Gel Electrophoresis (PFGE) and Southern hybridization were performed. Based on total DNA sequence data of strain C58 (Wood et al., 2001), it is estimated that the integration site of pRt4Sa::Tn5-mob would be located on putative P4-family integrase gene (int, 1191bp) of strain A136 linear chromosome. The nucleotide sequences of the left-junction of int -pRt4Sa::Tn5-mob, was included in int 1191-787 bp and right inverted region (IS50; 4285-5818 bp) of Tn5-mob connecting to pRt4Sa. The complete integration system of int gene, Tn5-mob, and pRt4Sa is in elucidation.
