Provided herein are a glucan kinase polypeptide, an isolated polynucleotide, and a method for processing starch. The glucan kinase polypeptide comprises an isolated polypeptide including a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO:22, fragments thereof, variants thereof, and combinations thereof. The isolated polynucleotide comprises a nucleotide sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 21, a fragment thereof, a variant thereof, and a combination thereof. The method for processing starch comprises providing a glucan dikinase; exposing a starch to the glucan dikinase; and collecting the starch that has been exposed to the glucan dikinase.

The specification provides methods of obtaining a genetically modified plant which has increased production potential compared to a control plant, the method comprising the steps of i) obtaining a plurality of plants at least one of which comprises in its genome a heterologous polynucleotide, ii) identifying from the plurality of plants a plant which has increased production potential relative to the control plant and comprises the heterologous polynucleotide, and iii) selecting the genetically modified plant, wherein the polynucleotide comprises a transcriptional control sequence operably linked to a nucleic acid sequence which encodes an agent that modifies endogenous starch phosphorylation and/or starch degradation in the plant. In some embodiments, the plant has increased endogenous glycosylase or increased digestibility compared to a control plant. In some specific embodiments, the endogenous starch phosphorylation and/or starch degradation is modified by modifying expression or activity of one or more enzymes selected from the group consisting of -amylase (EC 3.2.1.1), -amylase (EC 3.2.1.2), glucoamylase (EC 3.2.1.3), starch phosphorylase (EC2.4.1.1), glycosylase (EC 3.1.33), sucrase-isomaltase (EC 3.2.10), amylomaltase (EC 2.4.1.25), maltase (EC 3.2.1.20), isoamylase, and -glucan, water dikinase (GWD, EC 2.7.9.4).

Provided herein are a glucan kinase polypeptide, an isolated polynucleotide, and a method for processing starch. The glucan kinase polypeptide comprises an isolated polypeptide including a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO:22, fragments thereof, variants thereof, and combinations thereof. The isolated polynucleotide comprises a nucleotide sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 21, a fragment thereof, a variant thereof, and a combination thereof. The method for processing starch comprises providing a glucan dikinase; exposing a starch to the glucan dikinase; and collecting the starch that has been exposed to the glucan dikinase.

Genetically engineered plants expressing altered Glucan Water Dikinase and having elevated levels of starch are provided. Methods of genetically engineering plants to express altered Glucan Water Dikinase, and genetic constructs are provided. Methods of breeding genetically engineered plants homozygous for a mutated gene encoding an altered Glucan Water Dikinase are described. Methods of agricultural processing and animal feed using the genetically engineered plants are also provided.

Genetically engineered plants having altered levels of one or more starch regulation enzymes and a polysaccharide degrading enzyme are provided. Methods of genetically engineering plants to express products altering expression of one or more starch regulation enzymes and polysaccharide degrading enzymes, and genetic constructs are provided. Methods of agricultural processing and animal feed using the genetically engineered plants are described.