Restriction Endonuclease Map of pTi Bo542, a Potential Ti Plasmid Vector for Genetic Engineering of Plants

We report here a physical map of pTi Bo542, a wide-host-range tumor-inducing plasmid of Agrobacterium tumefaciens. Forty-two fragments generated by the restriction endonuclease Bam HI were arranged in a circular array using electrophoretic analysis of clones containing overlapping segments of pTi Bo542. The T-DNA region (the part of the Ti plasmid transferred to the plant) was predicted by its homology to T-DNAs from heterologous octopine and nopaline Ti plasmids. Southern hybridizations against soybean tumor DNA using clones from this region as probes confirmed this prediction.