So if these non covalent interactions cannot exist in that polypeptide, then that polypeptide has no way of knowing what the proper disulfide bonds are that have to be foreign. And so what happened in this experiment was because we initially removed the beta macapto ethanol before actually removing our urea, we saw that in our denatured mixture we had the urea. So the non covalent bonds could not actually form and they could not actually drive the correct formation of those disulfide bonds. And so because we had you read in the mixture improper incorrect disulfide bonds were actually formed. So when the beta mercapto ethanol was removed, first an inactive enzyme was formed. And this is because the improper disulfide bonds were formed because those non covalent reactions could not basically dictate the formation of those proper disulfide pairings.