Fructose and glucose phosphorylating enzyme. May be involved in the phosphorylation of glucose during the export from plastids to cytosol. Seems neither to be involved in cell sugar sensing nor in carbohydrate metabolism in tuber. ATP + D-hexose = ADP + D-hexose 6-phosphate + H(+) ATP + D-fructose = ADP + D-fructose 6-phosphate + H(+) ATP + D-glucose = ADP + D-glucose 6-phosphate + H(+) Measured in yeast lacking glucose and hexose kinase activity. Carbohydrate metabolism; hexose metabolism. Carbohydrate degradation; glycolysis; D-glyceraldehyde 3-phosphate and glycerone phosphate from D-glucose: step 1/4. Expressed in young and mature leaves, stems, roots, stolons, and developing and mature tubers. Belongs to the hexokinase family.