An iron sulfur protein now actually contains a ratio of four iron to four sulfur inorganic sulfide atoms. And this complex is found on the active side, and it binds not the hydroxyl onto the carboxylate ion group of the citrate. And that holds the citrate molecules within the active side and allows the catalysis to actually take place. So, once again, step two is a two step process. So we have this dehydration and hydration that is catalyzed by the connotase, which is an iron sulfur protein because it uses the iron sulfur complex to carry out these two reactions. Now, once we form the isocitrate molecule, now this six carbon molecule is ready to undergo the first oxidative decorboxylation step of the citric acid cycle.