Patents granted to Cornell

The patents disclose a vector (BiBAC) based on a bacterial artificial chromosome (BAC) and designed for Agrobacterium -mediated plant transformation.

The patents disclose that:

  • heterologous DNA cloned into the vector can be maintained in E. coli as a single copy,
  • the vectors can be transferred from E. coli to Agrobacterium (e.g., by triparental mating or by isolation from E. coli and electroporation into Agrobacterium), and
  • Agrobacterium used for plant transformation contains the BiBAC vector having a heterologous gene and a helper plasmid to facilitate the transfer of the foreign gene into the plant (a binary vector system).

Specific Patent Information

Patent Number Title, Independent Claims and Summary of Claims Assignee
US 5733744

  • Earliest priority – 13 January 1995
  • Filed – 13 January 1995
  • Granted – 31 March 1998
  • Expected expiry – 30 March 2015
Title – Binary BAC vector

Claim 1
A vector for transferring heterologous DNA into a plant cell, said vector comprising:

  • a backbone which includes a first origin of replication for maintaining heterologous DNA as a single copy in an Escherichia coli host cell, and which further includes a second origin of replication for maintaining heterologous DNA as a single copy in an Agrobacterium tumefaciens host cell;
  • a unique restriction endonuclease cleavage site for insertion of heterologous DNA; and
  • left and right Agrobacterium T-DNA border sequences flanking said unique restriction endonuclease cleavage site, said left and right T-DNA border sequences allowing introduction of heterologous DNA located between said left and right T-DNA border sequences into a plant cell.

The United States patent US 5733744 claims elements of a vector for transferring heterologous DNA into a plant. The elements are:

  • two different origins of replication, one for Agrobacterium and the other one for E. coli, each maintaining a plasmid as a single copy;
  • a unique restriction site where the heterologous DNA is inserted; and
  • right and left Agrobacterium T-borders flanking the heterologous DNA.

The patent discloses that “maintenance as a single copy refers to a non-replicating cell, i.e. a cell not undergoing cell division; during cell division, the copy per cell increases to nearly two complete copies per cell.

It’s not clear whether an “Agrobacterium T-border sequence” is one which must be found naturally in Agrobacterium.  The disclosure describes cloned sequences that were so derived.  A reading of the file history might be instructive.

Cornell

US 5977439

  • Earliest priority – 13 January 1995
  • Filed – 22 December 1997
  • Granted – 2 November 1999
  • Expected expiry – 21 December 2017
Title – Binary BAC vector

Claim 1
A method of making a transgenic plant transformed with a vector comprising:(1) providing a vector comprising: a backbone which includes a first origin of replication capable of maintaining heterologous DNA as a single copy in an Escherichia coli host cell, and which further includes a second origin of replication capable of maintaining heterologous DNA as a single copy in an Agrobacterium tumefaciens host cell, a unique restriction endonuclease cleavage site for insertion of heterologous DNA, a heterologous DNA encoding a gene product inserted into the unique restriction site, and left and right Agrobacterium T-DNA border sequences flanking said unique restriction endonuclease cleavage site, said left and right T-DNA border sequences allowing introduction of heterologous DNA located between said left and right T-DNA border sequences into a plant cell;
(2) introducing said vector into plant cells; and
(3) propagating plants from said plant cells.
Claim 17
A method of introducing heterologous DNA into a plant cell comprising:(1) providing a vector comprising: a backbone which includes a first origin of replication capable of maintaining heterologous DNA as a single copy in an Escherichia coli host cell, and which further includes a second origin of replication capable of maintaining heterologous DNA as a single copy in an Agrobacterium tumefaciens host cell, a unique restriction endonuclease cleavage site for insertion of heterologous DNA, a heterologous DNA encoding a gene product inserted into the unique restriction endonuclease cleavage site, and left and right Agrobacterium T-DNA border sequences flanking said unique restriction endonuclease cleavage site, said left and right T-DNA border sequences allowing introduction of heterologous DNA located between said left and right T-DNA border sequences into a plant cell; and
(2) introducing said vector into plant cells.

Methods for transforming a plant with the vector and obtaining transformed plants are claimed in the United States patent 5 977 439.

EP 805851 B1

  • Earliest priority – 13 January 1995
  • Filed – 11 January 1996
  • Granted – 26 May 2004
  • Expected expiry – 10 January 2016
Title – Binary BAC vector

Claim 1

A vector for transferring heterologous DNA into a plant cell, said vector comprising:

  • a backbone which includes a first origin of replication capable of maintaining heterologous DNA as a single copy in an Escherichia colihost cell, and which further includes a second origin of replication capable of maintaining heterologous DNA as a single copy in an Agrobacterium tumefaciens host cell;
  • a unique restriction endonuclease cleavage site for insertion of heterologous DNA; and
  • left and right Agrobacterium T-DNA border sequences flanking said unique restriction endonuclease cleavage site, said left and right T-DNA border sequences allowing introduction of heterologous DNA located between said left and right T-DNA border sequences into a plant cell.

Designated contracting States at the time of grant are: Austria (patent ceased as reported by EPO), Belgium (patent lapsed as reported by EPO), Switzerland (patent ceased as reported by INPADOC), Germany, Denmark (patent lapsed as reported by EPO), Spain (patent lapsed as reported by EPO), France, United Kingdom, Greece (patent lapsed as reported by EPO), Ireland (patent lapsed as reported by INPADOC), Italy, Liechtenstein (patent lapsed as reported by INPADOC), Luxembourg, Monaco (patent lapsed as reported by EPO), Netherlands (patent lapsed as reported by INPADOC), Portugal, Sweden (patent lapsed as reported by INPADOC).

EP 805851 A1

  • Earliest priority – 13 January 1995
  • Filed – 11 January 1996
  • Granted as EP 805851(see above)
Title – Binary BAC vector

Claim 1

A vector for transferring heterologous DNA into a plant cell, said vector comprising:

  • a backbone which includes a first origin of replication capable of maintaining heterologous DNA as a single copy in an Escherichia colihost cell, and which further includes a second origin of replication capable of maintaining heterologous DNA as a single copy in an Agrobacterium tumefaciens host cell;
  • a unique restriction endonuclease cleavage site for insertion of heterologous DNA; and
  • left and right Agrobacterium T-DNA border sequences flanking said unique restriction endonuclease cleavage site, said left and right T-DNA border sequences allowing introduction of heterologous DNA located between said left and right T-DNA border sequences into a plant cell.
Remarks National phase entry of WO 1996/21725 in Japan (JP H11/500306) is pending.

Note: Patent information on this page was last updated on 24 February 2006.