noun. An enzyme that catalyzes the shifting of a chemical group from one position to another within the same molecule.

noun. An enzyme that catalyzes the shifting of a functional group from one position to another within the same molecule.

"This demonstration of the part of mutase played by the co-zymase, or in other words of the identity of co-zymase and co-mutase, is of fundamental importance, for it has fully revealed the central position in the process of fermentation of the complementary enzyme in question."