3,3′-Dithiodipropionic acid forms monolayers on a polycrystalline gold electrode through a self-assembly procedure to form gold 3,3′-dithiodipropionic acid self-assembled monolayer modified electrode. It is the precursor substrate in the synthesis of 3-mercaptopropionic acid-containing polythioesters. It is added as primary carbon supplement in the culture medium of novel betaproteobacterium, strain DPN7.