Abstract:Recombinant peroxidase A4-Prx derived from Acinetobacter sp. SM04 and expressed by genetically-engineered recombinant Pichia pastoris GS115/pPIC9K-A4-Prx was purified to analyze its enzymatic characteristics and ability to degrade zearalenone (ZEA). Ammonium sulfate precipitation and dextran column elution were used to purify A4-Prx, with a final purification factor of 12. High-performance liquid chromatography (HPLC) showed that purified A4-Prx degraded ZEA at a rate of 63%. Further analysis of A4-Prx enzymatic characteristics showed that pH and temperature had significant effects on peroxidase activity; enzymatic activity peaked at pH 9.0 and 60 ℃. Lineweaver-Burk plots of A4-Prx peroxidase reaction showed that when H2O2 concentration was 9.7 mM, Km was 4.85 mM and Vmax was 204.1 U. A4-Prx also showed significant inhibitory effect on ethylenediaminetetraacetic acid (EDTA). These results provide preset conditions for subsequent research on the degradation mechanisms of A4-Prx and further research on ZEA biodegradation.
