Glyceraldehyde-3-phosphate dehydrogenase; part of the gene cluster that mediates the biosynthesis of heptelidic acid (HA), a sesquiterpene lactone that acts as an inhibitor of glyceraldehyde-3-phosphatedehydrogenase (GAPDH) and a growth inhibitor of the salt-tolerant lactic acid bacteria in soy sauce brewing (PubMed:30466366). The GAPDPH hepG/gdpB shows much higher resistance to HA than the GAPDH gpdA located outside of the cluster, but it does not seem to act in self-resistance (PubMed:30466366). D-glyceraldehyde 3-phosphate + NAD(+) + phosphate = (2R)-3-phospho-glyceroyl phosphate + H(+) + NADH Carbohydrate degradation; glycolysis; pyruvate from D-glyceraldehyde 3-phosphate: step 1/5. Homotetramer. Does not affect the biosynthesis of heptelidic acid. Belongs to the glyceraldehyde-3-phosphate dehydrogenase family.