Remember, the Acyl carrier protein actually contains a phosphate group and that group contains this sulf hydro group. And that will allow the binding of certain molecules as we'll see in just a moment. So this is our FAS and we have this ACP that contains the phosphate that is not shown, that contains this sulf Hydrol group and that will bind this molecule, the CETO coenzyme A as we'll see in just a moment. In addition, you also have to be aware of the cysteine residue that is also present in this FAS molecule because it will also play an important role as we'll see in just a moment. So step number one is catalyzed by one of the catalytic domains we call acetil transasilise and that is found on this FAS molecule. And so what this enzyme does or what this catalytic domain does is it catalyzed the attachment of this acetyl coenzyme A molecule onto this sulf hydro group and we generate this intermediate shown here.