EFFECTS OF IONIC AND ZWITTERIONIC SURFACTANTS ON THE STABILIZATION OFBOVINE CATALASE

The activity and stability of beef liver catalase have been investigat ed in the presence of different ionic and zwitterionic surfactants. Ah cationic and zwitterionic surfactants used in this work have no effec t on the initial activity of catalase, but several of them allow the e nzyme to retain a high residual activity for longer periods of time th an those observed in the absence of any additives. However, the intera ctions between surfactants and catalase appear to be very peculiar, an d certain zwitterionic surfactants have been found to remarkably: slow down enzyme degradation, with the enzyme completely preserving its ac tivity after several weeks at temperatures of up to 30 degrees C. This effect is probably due to an interaction between the surfactant and t he intersubunit region of the protein; this interaction could stabiliz e the quaternary structure of the enzyme.