Comparison of T-DNA oncogene complements of Agrobacterium tumefaciens tumor-inducing plasmids with limited and wide host ranges

W. G. Buchholz, M. F. Thomashow

Research output: Contribution to journalArticle

17 Scopus citations


The T-DNA oncogene complements of the limited-host-range tumor-inducing plasmid pTiAg63 and the wide-host-range plasmid pTiA6 were compared. The resulting data indicate that pTiAg63 has DNA sequences related to most of the genes encoded by the oncogenic region, the T(L)-DNA, of pTiA6 and that these sequences are divided between two T-DNA regions, the T(A)-DNA, which encoded sequences related to pTiA6 genes 4 (the cytokinin independence gene) and 6a, as well as to a pTiA6 T(L)-DNA fragment had encoded gene 6b and a portion of gene 3, and the T(B)-DNA, which encoded sequences related to genes 1 and 2 (the auxin independence genes). Tumor tissues of Nicotiana rustica incited by Agrobacterium tumefaciens harboring either pTiA6 or TiAg63 grew axenically in vitro on phytohormone-free medium. The morphologies of the tissues, however, differed; whereas those incited with pTiA6 grew as loose, friable, unorganized callus, the tumors incited by pTiAg63 grew as clumps of rootlike structures. Thus, the T-DNA oncogene complements of these plasmids were not equivalent. The results are discussed in relation to the A. tumefaciens host range.

Original languageEnglish (US)
Pages (from-to)319-326
Number of pages8
JournalJournal of bacteriology
Issue number1
StatePublished - Jan 1 1984


ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Cite this