Compositions and methods for expressing a multidomain enzyme in a plant are provided. The compositions include plants, seeds, plant tissues, and plant parts expressing a modified multidomain enzyme enzyme. The modified multidomain enzyme has a heterologous linker region that is not cleaved when the modified multidomain enzyme is expressed in a plant. In various embodiments, the linker region comprises the sequence set forth in SEQ ID NO:18, 19, or 20. Further provided are methods for producing a modified multidomain enzyme enzyme comprising cultivating plants expressing the modified multidomain enzyme. Downstream uses of transgenic plant material of the invention include agronomical and industrial uses, for example, human food, animal feed, pharmaceuticals, biofuel, industrial alcohol, fermentation feedstocks, and the like.