GROWTH AND PHENYLALANINE AMMONIA LYASE ACTIVITY OF Rhodotorula g/utinis: OPTIMIZATION OF CONDITIONS FOR THE SYNTHESIS OF L-PHENYLALANINE

Abstract

A procedure is described for the synthesis of L-phenylalanine from trans-cinnamic acid and ammonia utilizing the reverse reaction of phenylalanine ammonia lyase (PAL) from Rhodotoru/a glutinis. Optimal conditions determined for yeast growth and PAL production were pH 6, 1% inoculum, 30°C for 26-28 h. Optimization of conditions for maximal phenylalanine production included incubation time (16 -18 h), temperature (30°C), pH (9 .0), selected concentrations of substrates: 0.1 M trans-cinnamic acid and 4.0M NH40H and 0.1M Tris-HCI. Under these conditions about 85% conversion of substrate to product was obtained.