The four steps of beta oxidation are dehydrogenation, hydration, a second dehydrogenation and thiolytic cleavage, notes the University of Utah Health Sciences Library. A separate enzyme catalyzes each step.
The first step is dehydrogenation, and this step takes place between the alpha and beta carbons in a FAD-linked reaction, as explained at Study.com. The next step is hydration as the enzyme Enoyl-CoA gives a hydrogen back to the alpha carbon and adds an oxygen to the beta carbon. Then a second dehydrogenation takes place in a NAD-linked reaction. During the final phase, a thiolase-catalyzed reaction occurs that cleaves the beta-ketoacyl-CoA.