Cloning of the six mushroom tyrosinases
RNA extracted from fruiting bodies of Agaricus bisporus var. bisporus commercial hybrid Horst U1 at growth stages 1 – 5 was applied for the construction of cDNA-libraries using a poly-T primer. Tyrosinase genes were amplified from these libraries by PCR , cloned into suitable plasmids, subsequently sequenced and expressed in Escherichia coli. All six isoforms of mushroom tyrosinase were enzymatically active on both monophenolic and catecholic substrates.