Partial Purification and Some Properties of Tyrosine Phenol-Lyase from Aeromonas phenologenes ATCC 29063

Abstract

Tyrosine phenol-lyase was purified 32-fold from Aeromonas phenologenes ATCC 29063, the organism that produces phenol in refrigerated haddock. The purification procedure included ammonium sulfate fractionation, protamine sulfate treatment, and column chromatography with Sephadex G-200, diethyl-aminoethyl-cellulose, and hydroxyapatite. The enzyme was found to be thermally inactivated at temperatures above 40°C. The optimum pH of the enzyme was found to be pH 8.5. The Michaelis constants for l -tyrosine and pyridoxal phosphate were 2.3 × 10 -4 M and 3.2 × 10 -5 M, respectively. The molecular weight of tyrosine phenol-lyase was found by gel filtration and electrophoresis to be approximately 380,000.