And so let's focus on step one. In step one, we have a water molecule, this acetyl coenzyme a, as well as an oxyloacetate, react to ultimately produce a six carbon molecule known as citrate. So notice we begin with the oxyloacetate of four carbon molecules, so 1234. And we begin with this acetyl coenzyme a, that contains this two carbon component. And so ultimately, what happens in step one is the enzyme known as citrate synthase. Synthase catalyze.