<p> This family describes the type II glyceraldehyde-3-phosphate dehydrogenases which are limited to archaea. These enzymes catalyze the interconversion of 1,3-diphosphoglycerate and glyceraldehyde-3-phosphate, a central step in glycolysis and gluconeogenesis. In archaea, either NAD or NADP may be utilised as the cofactor.</p>