Laccases are multicoopper oxidases catalyzing the oxidation of phenolic as well as non-phenolic compounds. Laccases show typical blue color due to the presence of covalent Type 1 Cu-Cys bond which absorbs at 600 nm. However, recently some white laccases have also been identified which lacks typical spectra of blue laccases and do not show peak at 600 nm. In the present study, a novel white laccase was isolated from Bacillus sp. MSK-01. MSK laccase was purified and characterized in detail and the purified laccase was referred to MSKLAC. It has a molecular weight of 32 KDa. UV-visible spectrum of purified MSKLAC do not show characteristic peak at 600 nm and bend at 330 nm. The enzyme was repressed by conventional inhibitors of laccase like sodium azide, cysteine, dithiothreitol and β-mercaptoethanol. The laccase was highly thermo-stable enzyme having optimum temperature of 75 °C and could treasure more than 50% activity even at 100 °C. The optimum pH for ABTS and guaiacol was 4.5 and 8.0 respectively. MSKLAC was stable in the presence of most of the metal ions and surfactants. The effect of MSKLAC on lung cancer cell line was also assessed. It was observed that MSKLAC is inhibitory to lung cell cancer line. Thus, MSKLAC has potential to be used as an anti-proliferative agent to cancer cells.
Copyright © 2018. Published by Elsevier B.V.