A yellow laccase from the culture filtrate of Trametes hirsuta MTCC-1171 has been purified. The purification methods involved concentration of the culture filtrate by ammonium sulphate precipitation and an anion exchange chromatography on diethylaminoethyl cellulose. The sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis gave single protein band indicating that the enzyme preparation was pure. The molecular mass of the enzyme determined from SDS-PAGE analysis was 55.0 kDa. Using 2,6-dimethoxyphenol, 2,2'[azino-bis-(3-ethylbonzthiazoline-6-sulphonic acid) diammonium salt] and 3,5-dimethoxy-4-hydroxybenzaldehyde azine as the substrates, the K-m, k(cat) and k(cat)/K-m values of the laccase were found to be 420 mu M, 13.04 s(-1), 3.11 x 10(4) M-1 s(-1), 225 mu M, 13.03 s(-1), 1.3 x 10(5) M-1 s(-1) and 100 mu M, 13.04 s(-1), 5.8 x 10(4) M-1 s(-1), respectively. The pH and temperature optima were 4.5 and 60 degrees C, respectively while pH and temperature stabilities were pH 4.5 and 50 degrees C. The activation energy for thermal denaturation of the enzyme was 18.6 kJ/mol/K. The purified laccase has yellow colour and does not show absorption band around 610 nm like blue laccases. The purified laccase transforms toluene, 3-nitrotoluene, 4-nitrotoluene, 3-chlorotoluene, 4-chlorotoluene and 3,4-dimethoxytoluene to benzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde and 3,4-dimethoxybenzaldehyde in the absence of mediator molecules in high yields. (C) 2014 Elsevier Ltd. All rights reserved.