title: A T-DNA from the Agrobacterium tumefaciens limited-host-range strain AB2/73 contains a single oncogene.
abstract: Agrobacterium tumefaciens strain AB2/73 isolated from Lippia canescens has been described as a limited-host-range strain. Its tumor-inducing (Ti) plasmid has been found to lack DNA homology to known T-DNAs (L. Unger, S. F. Ziegler, G. A. Huffman, V. C. Knauf, R. Peet, L. W. Moore, M. P. Gordon, and E. W. Nester. J. Bacteriol. 164:723-730, 1985). We have isolated a T-DNA from AB2/73 by using a heterologous border sequence as a probe. The AB2/73 T-DNA sequence (3,504 bp) is flanked by canonical border sequences, has no detectable DNA homology with other T-DNAs, and contains only two genes: lsn (Lippia strain nopaline synthaselike gene) and lso (Lippia strain oncogene). The lso gene induces nondifferentiating tumors on a limited number of hosts when transferred by a Ti plasmid from a wide-host-range strain. Part of the predicted Lso protein is weakly homologous to other Agrobacterium oncoproteins encoded by rolB, rolB, orf13, gene e, gene 5, and gene 3'. A 28-kb fragment corresponding to the virA to virE region was cloned by using a heterologous vir fragment as probe. The AB2/73 vir region is homologous to most of the C58 virulence region; however, the virA gene is most related to the virA gene of the Agrobacterium vitis limited-host-range strain Ag162.
authors.affiliation: Department of Cell Biology, Plant Molecular Biology Institute of the C.N.R.S., Strasbourg, France. leon.otten@ibmp-ulp.u-strasbg.fr
authors.forename: L
authors.initials: L
authors.lastname: Otten
authors.forename: J
authors.initials: J
authors.lastname: Schmidt
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics* / Q000472:pathogenicity; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002874:Chromosome Mapping; D004269:DNA, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D015513:Oncogene Proteins / Q000235:genetics; D009857:Oncogenes; D010935:Plant Diseases / Q000382:microbiology; D017386:Sequence Homology, Amino Acid; D014774:Virulence / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; C112234:LSO protein, Agrobacterium tumefaciens; D015513:Oncogene Proteins; C036483:T-DNA