Glucose-6-phosphate isomerase, function

West JD, Flockhart JH, Peters J, Ball ST. Death of mouse embryos that lack a functional gene for glucose phosphate isomerase. Genet Res 1990 56 223-36. 

The glucose 6-phosphate thus formed can enter glycolysis or another pathway such as the pentose phosphate pathway, described in Section 14.5. Phosphoglucomutase employs essentially the same mechanism as phos-phoglycerate mutase (p. 531). The general name mu-tase is given to enzymes that catalyze the transfer of a functional group from one position to another in the same molecule. Mutases are a subclass of isomerases, enzymes that interconvert stereoisomers or structural or positional isomers (see Table 6-3). 

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