D Glyceraldehyde 3 phosphate dehydrogenase: Three dimensional structure and evolutionary significance

Abstract

A 3.0 Å resolution electron density map of lobster glyceraldehyde 3 phosphate dehydrogenase (EC 1.2.1.12) was computed. The essentially single unsuccessful replacement map was very substantially improved by averaging subunits. NAD binds in an open conformation at sites close to subunit interfaces. The coenzyme binding portion of the enzyme has almost the same fold as the corresponding portion of lactate dehydrogenase (EC 1.1.1.27). The presence of this structure in the 5 enzymes, analyzed so far, that use nucleotide coenzymes might indicate a fundamental primordial structural element.