In this video, we'll talk about the 6th class of enzymes, our ligases. Now here, they catalyze the covalent bonding of 2 molecules together with the use of ATP. So energy is required here. Now, we have 2 subclasses that belong to this class of enzymes. They are our synthetase and then our carboxylase. So, synthetases form a bond between 2 molecules. Carboxylases, they form a bond specifically between CO2 and another molecule.
If we take a look here, we have pyruvate. And next to pyruvate, we have CO2, the required ATP, and then our ligase in the form of pyruvate carboxylase. So, carboxylase means we want to add CO2 to our pyruvate molecule. So, this CH3 is going to have CO2 added to it. To do this, we have to sacrifice one hydrogen from the carbon because carbon can only make up to 4 bonds. Doing this transforms pyruvate into oxaloacetate. And we're going to say here we also create what, ADP as a byproduct because we have to use a phosphate from ATP. And then we also have our acid here that's formed +H+. So again, this represents a carboxylase because we had the joining of a carbon dioxide molecule with pyruvate, another molecule.
Alright. So keep this in mind when looking into the 6th class of enzymes and the 2 subclasses that belong to it.
