Comparison of Isomers of Fluorophenylalanine as Inhibitors of Ion Transport Across Barley Roots

Abstract

Earlier reports of inhibition of Cl^- transport across the root to the xylem by p-fluorophenylalanine (p-FPA) were used to support the need for continual production of a protein used as a carrier. It is now shown that o-FPA and m-FPA are also effective as inhibitors of transport, ruling out the possibility that p-FPA was acting by inhibition of phenylalanine ammonia-lyase activity and so changing endogenous concentration of phenolic compounds.