And so what we have to do is we have to take this molecule and we have to transform it into this molecule. Now, just like glucose is an isomer to fructose, DHAP is an isomer to gap because both of these are triosis and a trios is a three carbon sugar. So we have one, two, three carbons, one, two, three carbons. Both of these are triosis. So again, we have to depend on an enzyme called isomerase. What type of isomerase?