Order	Reaction ID	Reaction
1	R00016	protocatechuic acid + oxygen → 3-carboxy-cis,cis-muconate + 2H<sup>+</sup>
2	R00017	3-carboxy-cis,cis-muconate + H<sup>+</sup> → 2-carboxy-5-oxo-2,5-dihydrofuran-2-acetate
3	R00018	2-carboxy-5-oxo-2,5-dihydrofuran-2-acetate + H<sup>+</sup> → beta-ketoadipate-enol-lactone  + CO<sub>2</sub>
4	R00019	3-oxoadipate enol lactone + H<sub>2</sub>O → 3-oxoadipate + H<sup>+</sup>