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2,3-Bisphosphoglycerate-independent phosphoglycerate mutase (EC 5.4.2.1) was purified and characterized from maize. SDS electrophoresis showed only one band with a molecular mass of 64 kDa, similar to that determined for the native enzyme by gel-filtration chromatography. The kinetic constants were similar to those reported for wheat germ phosphoglycerate mutase. Rabbit antiserum against maize phosphoglycerate mutase possesses a high degree of specificity. It also reacts with the wheat germ enzyme but fails to react with other cofactor-independent or cofactor-dependent phosphoglycerate mutases. Cell-free synthesis experiments indicate that phosphoglycerate mutase from maize is not post-translationally modified.

In mammalian tissues three phosphoglycerate mutase (D-phosphoglycerate 2,3-phosphomutase, EC 5.4.2.1) isozymes result from the homo-dimeric and hetero-dimeric combinations of two subunits (types M and B). Whereas rabbit antisera against type M subunit (purified from rat muscle) and against type BB isozyme (purified from rat brain) possessed a high degree of specificity, both antisera reacted with type BB and MM isozymes, as demonstrated by immunoneutralization and ELISA. Both the M subunit and B subunit were more immunoreactive than their respective dimeric isozymes. Subunits type M and B may possess common antigenic determinants, and some of these determinants may be sterically hindered in their dimeric structures.