Characterization of a novel laccase purified from the fungus Hohenbuehelia serotina and its decolourisation of dyes.

Yingyin Xu; Yuxiao Lu; Rui Zhang; Hexiang Wang; Qinghong Liu

doi:10.18388/abp.2015_1091

Yingyin Xu State Key Laboratory for Agro-biotechnology, Department of Microbiology and Immunology, China Agricultural University. Beijing, People's Republic of China.;
Yuxiao Lu Department of Envioronmental and Chemical Engenineering, Tangshan College, People's Republic of China.;
Rui Zhang State Key Laboratory for Agro-biotechnology, Department of Microbiology and Immunology, China Agricultural University. Beijing, People's Republic of China.;
Hexiang Wang State Key Laboratory for Agro-biotechnology, Department of Microbiology and Immunology, China Agricultural University. Beijing, People's Republic of China.;
Qinghong Liu State Key Laboratory for Agro-biotechnology, Department of Microbiology and Immunology, China Agricultural University. Beijing, People's Republic of China.;

DOI: https://doi.org/10.18388/abp.2015_1091

Abstract

A novel laccase was purified from the white rot fungus, Hohenbuehelia serotina, to investigate the applications of this laccase in the decoloration of various dyes. SDS-PAGE revealed a single band of this laccase corresponding to a molecular weight of approximately 57.8 kDa. The enzyme showed activity towards several substrates, the most sensitive of which was 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS). The highest enzymatic activity using ABTS as a substrate was observed at pH 6.8 and 30°C. The enzyme activity was found to be significantly enhanced in the presence of Zn(2+) ions and inhibited by Fe(2+) ions. Moreover, SDS and β-mercaptoethanol were inhibitory, and inhibition by L-cysteine was observed while EDTA and DMSO had almost no inhibitory effect. The laccase could effectively decolorize seven different dyes within 30 minutes at 40°C.