Rerouting the photorespiration pathway in plants for increasing bioproduct yield
The present invention provides methods of producing biological products or increasing production of such products through expression in a plant of a bacterial or plant glycolate catabolic cycle gene, such as glycolate dehydrogenease (GDH), glycolate oxidase (GO), or malate synthase (MS) in combination with a plant gene, such as farnesyl diphosphate synthase (FPS), squalene synthase (SQS), or PLAS. Also provided are plants, plants parts and compositions produced through methods of the present invention. The invention leads to two to five fold increase of end product yield.
1. A method of producing a terpene in a Nicotiana plant, said method comprising expressing in the Nicotiana plant a bacterial glycolate oxidase (GO) or a bacterial glycolate dehydrogenase (GDH), and a bacterial malate synthase (MS) gene of the glycolate catabolic cycle and a plant farnesyl diphosphate synthase (FPS) and squalene synthase (SQS) gene, wherein the glycolate oxidase (GO), glycolate dehydrogenase (GDH), malate synthase (MS), farnesyl diphosphate synthase (FPS) and squalene synthase (SQS) genes each include a chloroplast transit peptide coding sequence.
2. The method of claim 1 , comprising further expressing in the Nicotiana plant a bacterial 1-deoxy-d-xylulose 5 phosphate synthase (DXPS) gene including a chloroplast transit peptide coding sequence.
3. The method of claim 1 , wherein expression of said bacterial genes in the Nicotiana plant produces an elevated level of said terpene.
4. The method of claim 3 , wherein the terpene is a monoterpene, sesquiterpene, diterpene, triterpene or tetraterpene.
5. The method of claim 4 , wherein the terpene is a triterpene.
6. The method of claim 1 , further comprising over-expression of said plant gene.
7. The method of claim 1 , wherein said bacterial and plant genes are co-expressed.
8. A Nicotiana plant produced by the method of claim 1 .
9. A part of the Nicotiana plant of claim 8 , wherein said part comprises (i) a bacterial glycolate oxidase or a bacterial glycolate dehydrogenase, (ii) a bacterial malate synthase gene of the glycolate catabolic cycle, (iii) a plant farnesyl diphosphate synthase, and (iv) a squalene synthase gene, wherein the glycolate oxidase, glycolate dehydrogenase, malate synthase, farnesyl diphosphate synthase, and squalene synthase genes each include a chloroplast transit peptide coding sequence.
10. The method of claim 5 , wherein the triterpene is squalene.