Comparative analysis of the white rot fungus Trametes hirsuta 072 laccases ability to modify 17β-oestradiol in the aqueous medium

A comparative study of the ability of Trametes hirsuta laccase isoenzymes to biotransform 17 beta-oestradiol (3,17 beta-dihydroxyestra-1,3,5(10)-triene, E2) was carried out. Native major LacA and recombinant minor isoenzymes (rLacC, rLacD, and rLacF) obtained in Penicillium canescens were used. It was found that all the studied isozymes are capable of catalysing the oxidative coupling of E2 in an aqueous medium (22 +/- 2 degrees C, pH 4.5) with the formation of predominantly dimers and trimers. Other concurrently formed products were detected by high-pressure liquid chromatography - high-resolution mass spectrometry (HPLC-HRMS) and characterized, summarizing the overall condensation pathway of E2 in laccases. The highest catalytic activity was observed for major LacA. For other laccases, the activity decreased in the following sequence rLacF > rLacD > rLacC. Utilization of T. hirsuta enzymatic variety of laccases can be of benefit for detoxification of phenol-like steroid compounds in the environment.