And the enzyme that catalyzes this reaction is known as gap dehydrogenase. Now, for gap dehydrogenase to actually function, it must be able to use a coenzyme we call nicotine amide adenine Dinucleotide in its oxidized form, namely NAD plus. And if it can't use NAD plus, if for some reason the NAD plus is not available in a cell, this process will essentially stop. An entire process of glycolysis will come to stop. Now, the problem with step six and the remaining steps of glycolysis is once the cell uses up NAD plus and transforms it into NADH, that NAD plus is not actually regenerated. So in the process of glycolysis, we use up NAD plus molecules to form the nadhs.