Characterisation of 2-Cys peroxiredoxin isozyme (Prx1) from Taiwanofungus camphorata (Niu-chang-chih): Expression and enzyme properties

Peroxiredoxins (Prxs) are a family of antioxidant peroxidases. The functions of Prxs comprises of cell protection against oxidative stress and regulation of cell proliferation. A putative 2-Cys Prx isozyme (Prx1) cDNA was cloned from Taiwanofungus camphorata (commonly known as Niu-chang-chih in Taiwan). The deduced amino acid sequence is conserved amongst the reported Prxs. A 3-D homology structure was created for this Prx1. To characterise the T. camphorata Prx1, the coding region was subcloned into a pAVD10 and transformed into Escherichia coli. The recombinant 6His-tagged Prx1 was expressed and purified by Ni2+-nitrilotriacetic acid sepharose. The purified enzyme showed two forms using a 15% SDS–PAGE. The enzyme retained 60% activity at 60 °C for 2.5 min. The enzyme was stable under a broad pH range from 5 to 11. The enzyme showed 57% activity after 40 min of incubation at 37 °C with trypsin. The ability of the enzyme to protect intact supercoiled plasmid DNA from ·OH induced nicking was demonstrated.