Mobilisable vectors - Patent Application filed by University of Leiden

US 2003/87439 A1

• Earliest priority - 1 March 2000
• Filed - 3 September 2002
• Application pending

Title - Transformation of eukaryotic cells by mobilizable plasmids

The independent claims of the present patent application recite:

• a method for transferring material to a eukaryotic cell by:
  • using a mobilisable plasmid capable of forming a relaxosome;
  • placing the plasmid into Agrobacterium , which provides the same or similar functions of the virB operon; and
  • co-cultivating the Agrobacterium with the eukaryotic host.

• a mobilisable plasmid for Agrobacterium -mediated transfer to an eukaryotic host comprising:
  • a functional oriT;
  • virD-like mobilization products;
  • virD4-like coupling factor; and
  • virB-like activities.

If the claims are granted as submitted, the resulting patent would provide protection for a broad spectrum of plasmids used for transformation via Agrobacterium. Binary and co-integrated vectors are based on the Ti-plasmid of Agrobacterium and the DNA transferred is always surrounded by T-DNA borders, while the plasmids of the present invention are derived from other bacterial sources, mainly bacteria from the family Enterobacteriaceae and do not use T-DNA borders for DNA transfer. Notice that the invention as filed is not limited to plants; all eukaryotic organisms may be encompassed by the claims in case of being granted as filed.

The structural and functional constraints on vir-like proteins are not disclosed- e.g., how much sequence difference/functional difference is tolerated for a protein to still be considered vir-like? The application merely repeats the claim language in the disclosure. The disclosure is also vague about the nature of gene products that would have activities "similar" to that of a functional virB operon though it indicates that homologues from other species are contemplated.

University of Leiden

1. Priority application of WO 2001/64925 from Europe (EP 1130105 A1) is deemed to be withdrawn on 15 January 2003.
2. National phase entry of WO 2001/64925 A1 in Europe (EP 1407031 A1) is pending.
3. National phase entry of WO 2001/64925 A1 in Australia (AU 41271/01) and Canada (CA 2401909) are pending.