So we have our seven transmembrane helix receptor that basically is bound to the G protein. But when that ligand, the primary messenger shown in orange actually binds onto the seven TM receptor that G protein, the G alpha protein to be more specific actually detaches and goes on and binds onto a dentalt cyclase. And then the cyclase basically transforms ATP into cyclic amp that goes on and binds and activates protein kinase A and protein kinase A goes on and affects different types of enzymes and protein effectors. 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?