Commercial production of polysaccharide degrading enzymes in plants and methods of using same

Abstract

Expression of recombinant polysaccharide degrading enzymes in plants is described. In one embodiment, expression of the enzyme is preferentially directed to the seed of the plant. Expression may also be preferentially targeted to specific locations within the plant cell. Expression of cellulases in corn is shown. The result is the capacity to produce polysaccharide degrading enzymes in plants at commercially acceptable levels in a reliable manner. Methods of using same in production of ethanol is also described, including use of the plant-produced enzymes in the ethanol production process.

1 . A transgenic plant comprising a nucleic acid encoding a β-1,4-endoglucanase (EC 3.2.1.4), and a targeting sequence, wherein said nucleic acid is stably integrated into the nuclear genome of a cell of said plant and is operably linked to a promoter and wherein said target sequence targets the β-1,4-endoglucanase to the cell wall. 
     
     
         2 . A transgenic plant comprising a nucleic acid encoding a β-1,4-endoglucanase (EC 3.2.1.4), and a targeting sequence, wherein said nucleic acid is stably integrated into the nuclear genome of a cell of said plant and is operably linked to a promoter and wherein said target sequence targets the β-1,4-endoglucanase to the endoplasmic reticulum. 
     
     
         3 . A transgenic seed comprising a nucleic acid encoding a β-1,4-endoglucanase (EC 3.2.1.4), and a targeting sequence, wherein said nucleic acid is stably integrated into the nuclear genome of a cell of said seed and is operably linked to a promoter and wherein said target sequence targets the β-1,4-endoglucanase to the cell wall. 
     
     
         4 . A transgenic seed comprising a nucleic acid encoding a β-1,4-endoglucanase (EC 3.2.1.4), and a targeting sequence, wherein said nucleic acid is stably integrated into the nuclear genome of a cell of said seed and is operably linked to a promoter and wherein said target sequence targets the β-1,4-endoglucanase to the endoplasmic reticulum.