And so that's why we call this structure a dihydroxy acetone, and it ultimately came from the first product molecule. And this dihydroxy acetone is transferred onto the second product, the second substrate molecule. So this is substrate number one and substrate number two. And so we have the transfer of this thy hydroxy acetone from one of the substrates to the other substrate. And so we formed these two product molecules. And unlike in the transketulase case, which used the Thiamine Pyrophosphate Cofactor molecule.