CATALASE OF THE METHYLOTROPHIC YEAST HANSENULA-POLYMORPHA - PURIFICATION AND PROPERTIES

The catalase of the methylotrophic Yeast Hansenula polymorpha was purified to a homogeneous state. The purification steps included fractionation with ammonium sulfate, chromatography on DEAE- and butyl- Toyopearl, and gel filtration on Ultragel AcA 44. The protein with molecular weight 232 kD consists of four identical subunits with molecular weight 60 kD and has the typical absorption spectrum for hemoproteins. The apparent K(m) with respect to H2O2 is equal to 24 mM. The enzyme has a broad pH optimum of activity - 5.8-8.5. The 3-amino-1,2,4-triazole, KCN, and NaN3 concentrations at which complete inhibition of the enzyme is observed at pH 7.0 without preincubation are 50, 3.5, and 0.15 mM, respectively. This enzyme is close in properties to the catalase purified from Candida-boidinii.