title: Biochemical Evaluation of Phenylalanine Ammonia Lyase from Endemic PlantCyathobasis fruticulosa(Bunge) Aellen. for the Dietary Treatment of Phenylketonuria.
abstract: Enzyme substitution therapy with the phenylalanine ammonia lyase (PAL) is a new approach to the treatment of patients with phenylketonuria (PKU). This enzyme is responsible for the conversion of phenylalanine totrans-cinnamic acid. We assessed the PAL enzyme of the endemic plantCyathobasis fruticulosa(Bunge) Aellen. for its possible role in the dietary treatment of PKU. The enzyme was found to have a high activity of (64.9±0.1) U/mg, with the optimum pH, temperature and buffer (Tris-HCl and l-phenylalanine) concentration levels of pH=8.8, 37 °C and 100 mM, respectively. Optimum enzyme activity was achieved at pH=4.0 and 7.5, corresponding to pH levels of gastric and intestinal juice, and NaCl concentration of 200 mM. The purification of the enzyme by 1.87-fold yielded an activity of 98.6 U/mg. PAL activities determined by HPLC analyses before and after purification were similar. Two protein bands, one at 70 and the other at 23 kDa, were determined by Western blot analysis of the enzyme. This enzyme is a potential candidate for serial production of dietary food and biotechnological products.
authors.affiliation: Gazi University, Faculty of Science, Department of Biology, TR-06500 Teknikokullar, Ankara, Turkey.
authors.forename: Seda
authors.initials: S
authors.lastname: Şirin
authors.affiliation: Gazi University, Vocational High School of Health Services, TR-06830 Gölbaşı, Ankara, Turkey.
authors.forename: Selcen Babaoğlu
authors.initials: SB
authors.lastname: Aydaş
authors.affiliation: Gazi University, Faculty of Science, Department of Biology, TR-06500 Teknikokullar, Ankara, Turkey.
authors.forename: Belma
authors.initials: B
authors.lastname: Aslım
keywords: Cyathobasis fruticulosa; endemic plant; enzyme purification; phenylalanine ammonia lyase (PAL); phenylketonuria (PKU)