Self processing plants and plant parts

• US 7,855,322 B2
• Filed: 05/26/2009
• Issued: 12/21/2010
• Est. Priority Date: 08/27/2001
• Status: Expired due to Term

• Current Assignee: Syngenta Participations AG (China National Chemical Corporation)
• Original Assignee: Syngenta Participations AG (China National Chemical Corporation)
• Inventors: Kinkema, Mark, Lanahan, Michael B., Batie, Christopher J, Chen, Wen, Basu, Shib Sankar, Craig, Joyce
• Primary Examiner(s): Fox; David T
• Application Number:
  US12/471,564
• Publication Number:
  US 20090288232A1
• Time in Patent Office: 574 Days
• Field of Search: None
• US Class Current: 800/284
• CPC Class Codes: C12N 15/8245 involving modified carbohydrate or sugar alcohol metabolism, e.g. starch biosynthesis
• CPC Class Codes: C12N 9/2408 acting on alpha -1,4-glucosidic bonds
• CPC Class Codes: C12N 9/2411 Amylases
• CPC Class Codes: C12N 9/2414 Alpha-amylase (3.2.1.1.)
• CPC Class Codes: C12N 9/2422 from plant source
• CPC Class Codes: C12N 9/2428 Glucan 1,4-alpha-glucosidase (3.2.1.3), i.e. glucoamylase
• CPC Class Codes: C12N 9/2451 acting on alpha-1,6-glucosidic bonds
• CPC Class Codes: C12N 9/2457 Pullulanase (3.2.1.41)
• CPC Class Codes: C12N 9/246 Isoamylase (3.2.1.68)
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: C12Y 302/01001 Alpha-amylase (3.2.1.1)
• CPC Class Codes: C12Y 302/01003 Glucan 1,4-alpha-glucosidase (3.2.1.3), i.e. glucoamylase
• CPC Class Codes: C12Y 302/0102 Alpha-glucosidase (3.2.1.20)
• CPC Class Codes: C12Y 302/01041 Pullulanase (3.2.1.41)
• CPC Class Codes: C12Y 302/01068 Isoamylase (3.2.1.68)
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

The invention provides polynucleotides, preferably synthetic polynucleotides, which encode processing enzymes that are optimized for expression in plants. The polynucleotides encode mesophilic, thermophilic, or hyperthermophilic processing enzymes, which are activated under suitable activating conditions to act upon the desired substrate. Also provided are “self-processing” transgenic plants, and plant parts, e.g., grain, which express one or more of these enzymes and have an altered composition that facilitates plant and grain processing. Methods for making and using these plants, e.g., to produce food products having improved taste and to produce fermentable substrates for the production of ethanol and fermented beverages are also provided.

Claims

1. An expression cassette comprising a polynucleotide encoding an alpha-amylase operably linked to a promoter and a heterologous signal sequence, wherein the alpha-amylase is thermophilic, and wherein the heterologous signal sequence directs the alpha-amylase to a specific compartment allowing the alpha-amylase to be localized in a manner that it will not come into contact with its substrate.

2. The expression cassette of claim 1, wherein the expression cassette directs the alpha-amylase to a specific compartment wherein the alpha-amylase can be contacted with its substrate by the process of milling or heating.

3. The expression cassette of claim 1, wherein the polynucleotide comprises a polynucleotide which encodes a polypeptide comprising SEQ ID NO:

10.

4. The expression cassette of claim 1, wherein the promoter is a seed-specific promoter.

5. The expression cassette of claim 4, wherein the seed-specific promoter is an endosperm-specific promoter.

6. The expression cassette of claim 5, wherein the endosperm-specific promoter is a maize gamma-zein promoter or a maize ADP-gpp promoter.

7. The expression cassette of claim 1, wherein the heterologous signal sequence targets the alpha-amylase enzyme to a vacuole, endoplasmic reticulum, seed or cell wall of a plant.

8. The expression cassette of claim 1, wherein the promoter is an endosperm-specific promoter and the heterologous signal sequence targets the alpha-amylase to the endoplasmic reticulum.

9. A cell comprising the expression cassette of claim 1.

10. A plant comprising the expression cassette of claim 1.

11. Seed, fruit, grain or plant part comprising the expression cassette of claim 1.

12. The cell of claim 9, which is selected from the group consisting of an Agrobacterium cell, a monocot cell, a dicot cell, a Liliopsida cell and a Panicoideae cell.

13. An expression cassette comprising a polynucleotide encoding an alpha-amylase operably linked to a promoter and a heterologous signal sequence, wherein the promoter is a seed-specific promoter, and wherein the heterologous signal sequence directs the alpha-amylase to a specific compartment allowing the alpha-amylase to be localized in a manner that it will not come into contact with its substrate.

14. The expression cassette of claim 13, wherein the expression cassette directs the alpha-amylase to a specific compartment wherein the alpha-amylase can be contacted with its substrate by the process of milling or heating.

15. The expression cassette of claim 13, wherein the alpha-amylase is thermophilic.

16. The expression cassette of claim 13, wherein the polynucleotide comprises a polynucleotide which encodes a polypeptide comprising SEQ ID NO:

10.

17. The expression cassette of claim 13, wherein the seed-specific promoter is an endosperm-specific promoter.

18. The expression cassette of claim 17, wherein the endosperm-specific promoter is a maize gamma-zein promoter or a maize ADP-gpp promoter.

19. The expression cassette of claim 13, wherein the heterologous signal sequence targets the alpha-amylase enzyme to a vacuole, endoplasmic reticulum, seed or cell wall of a plant.

20. A cell comprising the expression cassette of claim 13.

21. A plant comprising the expression cassette of claim 13.

22. Seed, fruit, grain or plant part comprising the expression cassette of claim 13.

23. The cell of claim 20, which is selected from the group consisting of an Agrobacterium cell, a monocot cell, a dicot cell, a Liliopsida cell and a Panicoideae cell.