title: Purification and Characterization of a White Laccase with Pronounced Dye Decolorizing Ability and HIV-1 Reverse Transcriptase Inhibitory Activity from Lepista nuda.
abstract: A strain LN07 with high laccase yield was identified as basidiomycete fungus Lepista nuda from which a white laccase without type I copper was purified and characterized. The laccase was a monomeric protein with a molecular mass of 56 kDa. Its N-terminal amino acid sequence was AIGPAADLHIVNKDISPDGF. Besides, eight inner peptide sequences were determined and lac4, lac5 and lac6 sequences were in the Cu(2+) combination and conservation zones of laccases. HIV-1 reverse transcriptase was inhibited by the laccase with a half-inhibitory concentration of 0.65 μM. Cu(2+) ions (1.5 mM) enhanced the laccase production and the optimal pH and temperature of the laccase were pH 3.0 and 50 °C, respectively. The Km and Vmax of the laccase using ABTS as substrate were respectively 0.19 mM and 195 μM. Several dyes including laboratory dyes and textile dyes used in this study, such as Methyl red, Coomassie brilliant blue, Reactive brilliant blue and so on, were decolorized in different degrees by the purified laccase. By LC-MS analysis, Methyl red was structurally degraded by the laccase. Moreover, the laccase affected the absorbance at the maximum wavelength of many pesticides. Thus, the white laccase had potential commercial value for textile finishing and wastewater treatment.
authors.affiliation: Department of Fungal Resource, College of Plant Protection, Shandong Agricultural University, 61, Daizong Street, Tai'an 271018, China. mengfan7777@163.com.|State Key Laboratory for Agrobiotechnology, Department of Microbiology, China Agricultural University, Beijing 100193, China. mengfan7777@163.com.
authors.forename: Mengjuan
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Urban Agriculture (North) of Ministry of Agriculture, College of Biological Science and Engineering, Beijing University of Agriculture, Beijing 102206, China. zhanggqbua@163.com.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Fungal Resource, College of Plant Protection, Shandong Agricultural University, 61, Daizong Street, Tai'an 271018, China. mengli0121@126.com.
authors.forename: Li
authors.initials: L
authors.lastname: Meng
authors.affiliation: State Key Laboratory for Agrobiotechnology, Department of Microbiology, China Agricultural University, Beijing 100193, China. hxwang@cau.edu.cn.
authors.forename: Hexiang
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Fungal Resource, College of Plant Protection, Shandong Agricultural University, 61, Daizong Street, Tai'an 271018, China. kxgao63@163.com.
authors.forename: Kexiang
authors.initials: K
authors.lastname: Gao
authors.affiliation: School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China. b021770@mailserv.cuhk.edu.hk.
authors.forename: Tb
authors.initials: T
authors.lastname: Ng
mesh_terms: D000363:Agaricales / Q000201:enzymology*; D003116:Color; D004396:Coloring Agents / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors / Q000737:chemistry; D015497:HIV-1 / Q000187:drug effects / Q000472:pathogenicity; D006801:Humans; D042845:Laccase / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D008970:Molecular Weight; D013379:Substrate Specificity; D062065:Wastewater / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D003300:Copper; D054303:HIV Reverse Transcriptase; D042845:Laccase; D062065:Wastewater; C514824:reverse transcriptase, Human immunodeficiency virus 1
keywords: HIV-1 reverse transcriptase inhibitory activity; dye decolorizing ability; laccase; purification; sequence