A brief history of the development of BIBAC technology:

Carol M. Hamilton, Ph.D.
The binary-BAC system for transformation of plants with high molecular weight DNA was developed at the Plant Science Center, Cornell University.

I (CMH) joined the research group at the Plant Science Center in March, 1992. The Plant Science Center was funded by a joint USDA, NSF, DOE grant and was under the direction of Dr. Maureen Hanson.

After about a year of work had been invested in the design and construction of a binary-BAC vector, Dr. Steve Tanksley invited me (CMH) to come to his lab group meetings and initiate a collaboration. Steve Tanksley provided invaluable technical and scientific support, and interacting with his research team at that time was as exciting as it was productive.

Additional funding was obtained from the USDA Plant Genome National Research Initiative, Plant Genome via the competitive grant program. This funding was a three year “New Investigator Award” ($255,000) to CMH. The USDA award made it possible for me to hire Dr. Anne Frary and Yimin Xu who continued to work on the project until I left Cornell in the spring of 1998.

To learn the “state of the art” of BAC library construction I accepted an invitation to work with Dr. Hong-Bin Zhang in his laboratory at Texas A&M. In addition to the USDA funding and support from the Tanksley laboratory, funding for the construction of two tomato genomic BIBAC libraries was provided by: Dr. Jonathan Jones at the John Innes Institute, UK, Dr. Robert Fluhr at the Weizmann Institute, Israel and Dr. Barbara Baker at UC Berkeley

BIBAC materials have been sent to hundreds of laboratories and companies around the world. BIBAC materials “for research purposes only” are currently available from the Plant Science Center, Cornell University. BIBAC technology is available for licensing from the Center for Technology Licencing at Cornell University (CTL). The Binary-BAC vector is described in U.S. patents: The BIBAC vector Hamilton, C. M. Binary BAC Vector. United States Patent No. 5,733,744. Issued March 31, 1998. Cornell Research Foundation, Inc., Ithaca, NY. And Binary BAC Vector Hamilton, C. M. United States Patent No. 5,977,439. Issued November 2, 1999. Cornell Research Foundation, Inc., Ithaca, NY.

USDA Final Report, due 23 Feb 1999:
National Research Initiative Competitive Grants Program
(NRICGP) Award: 9500764

“Evaluation and application of a new BAC library vector designed for transfer of large DNA inserts to plants”

Hamilton, CM
Cornell University
Plant Science Center
Ithaca, NY 14853-2703
3 years

Specific Aims
The specific aims of this proposal were to

  1. complete the construction and test of a new vector suitable for transformation of plant with high molecular weight
  2. test the utility of this vector for the construction of large insert genomic DNA libraries
  3. establish the utility of this new vector by identifying a gene of interest from a library constructed in this vector by plant transformation and complementation of a phenotype.

A new binary-BAC (bacterial artificial chromosome) vector was constructed. Evaluation of the new vector binary-BAC (BIBAC) demonstrated that the BIBAC was be capable of transferring at least 150 kb of DNA, intact, to the plant nuclear genome.

The vector was also designed to be suitable for the construction of high molecular genomic DNA libraries so that additional subcloning steps would not be needed. To demonstrate that the BIBAC vector is suitable for constructing large insert genomic DNA libraries, we set out to make high molecular DNA libraries for two different tomato species, Lycopersicon esculentum, domesticated
tomato, and L. pennellii, a wild species of tomato. The average insert sizes for these libraries were 125 and 90 kb respectively.

The final goal of the project, which was to demonstrate the utility of the system by identification of a gene of interest by using a BIBAC genomic library clone to complement a gene of interest, has not yet been achieved. However, work is currently underway in several laboratories that may serve to validate this intended application.

The advent of BIBAC technology has made it possible to consider new approaches to long-standing problems in basic plant biology and will facilitate the development of new elite varieties of agronomic crops. BIBAC technology will accelerate the identification of agriculturally important genes and make it possible to introduce valuable traits into plants without dragging along deleterious traits (a common problem for classical plant breeders). The ability to introduce high molecular weight DNA, intact into plant chromosomes will also make it possible to investigate long distance affects
on gene expression.

The BIBAC system for transfer of high molecular weight DNA to plants would not have been successful without enhancing the ability of Agrobacterium tumefaciens to effect DNA transfer to the plant chromosomes. That is, this work included basic research that has affected the plant transformation community. Several groups have contacted have requested the virulence helper plasmids that made BIBAC technology a success, not because they needed BIBAC technology per se, but because they were interested in improving the transformation efficiency for their plant system of interest. In general this is a more common problem for agronomic crops than for model system plants used for basic research.

The critical elements of this new technology, the bacterial strains and plasmids, have been requested by hundred of laboratories, academic and industrial, around the world. I have included the list of “all recipients” of BIBAC materials as an indication of the interest and potential impact of the development of this technology.

In addition, various parties have expressed interest in licensing BIBAC technology; these queries are directed to Cornell Research Foundation. A US patent has been issued for the BIBAC vector and foreign patents are pending. The Center for Advanced Technology/Biotechnology at Cornell University supported the construction and maintains a “BIBAC website” in support of BIBAC technology.

News Reports:


  • Frary, A., and Hamilton, C.M. 1999. Evaluation of BIBAC technology for transformation of tomato plants with high molecular weight DNA. Manuscript in preparation.
  • Hamilton, C. M., Frary, A., Xu, Y., Tanksley, S. D. and H. Zhang. 1999. Construction and characterization of BIBAC genomic DNA libraries of Lycopersicon esculentum andLycopersicon pennelli. The Plant Journal. 17: in press.
  • Hamilton, C. M. Binary BAC Vector. United States Patent No. 5,733,744. Issued March 31, 1998. Cornell Research Foundation, Inc., Ithaca, NY.
  • Hamilton, C. M. Binary BAC Vector. United States Patent No. 5,977,439. Issued November 2, 1999. Cornell Research Foundation, Inc., Ithaca, NY.
  • Hamilton, C. M. 1998. BIBAC technology: progress and prospects. AgBiotech News and Information (CABI) 10: 23N-28N.
  • Hamilton, C. M. 1997. A binary-BAC system for plant transformation with high-molecular-weight DNA. Gene 200: 107-116.
  • Hamilton C. M., Frary, A. Lewis, C. and Tanksley, S. D. 1996. Stable transfer of intact high molecular weight DNA into plant chromosomes. Proc. Natl. Acad. Sci. USA 93: 9975-9979.

Contact Information:

Contact at Cornell to obtain strains and plasmids:
Dr. Maureen Hanson
For scientific questions about the BIBAC vectors:
Carol M. Hamilton