Isochorismate pyruvate lyase (IPL, EC 4.2.99.21) is an enzyme responsible for catalyzing part of the pathway involved in the formation of salicylic acid. More specifically, IPL will use isochorismate as a substrate and convert it into salicylate and pyruvate. IPL is a PchB enzyme originating from the pchB gene in Pseudomonas aeruginosa.