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. 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