So now that we have an active CO2 molecule, it is ready to be attached onto the biotin component of that enzyme. And that's exactly what happens in step two. Now, I should mention that there is a requirement to attach that CO2 onto the biotin. This attachment only takes place if we have a coenzyme present attached onto that enzyme known as acetyl, coenzyme A or acetylCoA. So this enzyme is required for the CO2 to actually bind onto that biotin. And the coenzyme has to be bound onto that Pyruvate carboxylate for the step to actually take place.