Improved Bioremediation of Soils Contaminated with Toxic Metals Using Transgenic Plants Overexpressing Phytochelatan Synthetase
This method of bioremediation is of particular use in removing heavy metals and certain radioactive metals that could be associated with industrial or nuclear mishap contamination of wide areas. Bioremediation systems using plants are often restricted to certain species -- this approach allows the combining of the most suitable plant for the task/environment with overexpression of the high-capacity metal uptake transporter.
A CDNA encoding a novel cation transporter having broad specificity for metals has been isolated and characterized from a wheat root CDNA library. Clones incorporating this ion uptake transporter can be transferred to species of plants having deep root systems and rapid growth on a variety of soils. With the metal transporter over-expressed in specific plant tissues, these transgenic plants can be made capable of accumulating a variety of toxic metals from the soil and concentrating them on leaf surfaces or internally. Metal ions targeted by this system include: cadmium, lead, zinc, nickel, antimony, mercury, silver, tin, copper, cobalt, cesium, strontium, radium, uranium and osmium. Beryllium and aluminum are not effectively transported by this system. By a repetitive process of extensive planting, harvesting and incineration of the contaminated biomass, the metal toxicant in the soil can be reduced to acceptable levels.
Patent Number: US6489537B1
Application Number: US1999354123A
Inventor: Rea, Philip A. | Vatamaniuk, Olena K. | Mari, Stephane | Lu, Yu Ping | Schroeder, Julian I. | Kim, Eugene J. | Clemens, Stephan
Priority Date: 7 Aug 1998
Priority Number: US6489537B1
Application Date: 15 Jul 1999
Publication Date: 3 Dec 2002
IPC Current: A01H000500 | B09C000110 | C02F000332 | C12N000115 | C12N000119 | C12N000121 | C12N000510 | C12N000910 | C12N001505 | C12N001509 | C12N001529 | C12N001531 | C12N001582 | C12P002102
US Class: 800278 | 4350691 | 4353201 | 435419 | 435468 | 5360231 | 5360232 | 5360236 | 5360237 | 800288 | 800295 | 800298 | 800306 | 8003203
Assignee Applicant: The Trustees of the University of Pennsylvania,Philadelphia,PA | University of California Jolla
Title: Phytochelatin synthases and uses therefor
Usefulness: Phytochelatin synthases and uses therefor
Summary: The nucleic acid is useful for generating a transgenic heavy metal resistant plant or for removing a heavy metal from groundwater (claimed).
Novelty: New nucleic acid encoding phytochelatin synthase, useful for generating a transgenic heavy metal resistant plant or for removing a heavy metal from groundwater
Agriculture
Plant
6489537
State Of Development The process has been demonstrated at laboratory scale using transgenic yeast to remove cadmium and lead. The constructs are suitable for use in transforming higher plant species of interest using established protocols. Related Materials Business Week, February 14,1996, see also Case No. (96-102) Tech ID/UC Case 19373/1999-007-0 Related Cases 1999-007-0
USA
