Galactose-glucose interconversion pathway

Galactose is converted into glucose 6-phosphate in four steps. The first reaction in the galactose—glucose interconversion pathway is the phosphorylation of galactose to galactose 1 -phosphate by galactokinase. 

Plants also contain the enzymes necessary for interconverting the hexoses. The reactions shown in Fig. 6 represent some of the known pathways for these interconversions. When barley plants were infiltrated 71) with D-glucose, D-fructose, D-galactose, or D-mannose, sucrose accumulated hence the enzymes were present for interconverting these sugars. Mechanisms for these interconversions are discussed in several reviews 72 73) (see also Section 3B of this chapter). 

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