So let's suppose we have this bacterial cell and so basically in step one what the cell does is once it makes its way into the lumen it begins producing and releasing the cholera toxin we call cholera jen. And so this is basically what it looks like in step one. Now, what exactly is the structure of this particular toxin? Well, basically it's a protein that contains six subunits. Five of these subunits are identical and the other one is different. So five of these units are known as the B chains and the other unit is known as the A chain.