Cultural Conditions for the Microbial Production of β-Tyrosinase and Tryptophanase

Abstract

β-Tyrosinase (tyrosine phenol-lyase: EC 4.1.99.2) and tryptophanse (tryptophan indole-lyase: EC 4.1.99.1) are enzymes which respectively catalyze the degradation of L-tyrosine and L-tryptophan, and require pyridoxal 5’-phosphate (PLP) as a cofactor. Crystalline preparations of these enzymes were prepared in our laboratories from Escherichia intermedia and Proteus rettgeri, and their properties were established in some detail. The crystalline enzymes were shown to catalyze a variety of α,β-elimination (Eq. 1), β-replacement (Eq. 2), and the reverse of α,β-elimination reactions (Eq. 3) (1–3).