Comparative characterization of four laccases from Trametes versicolor concerning phenolic C–C coupling and oxidation of PAHs

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• 作者：Katja Koschorreck ; Sven M. Richter ; André ; Swierczek ; Uwe Beifuss ; Rolf D. Schmid ; Vlada B. Urlacher
• 关键词：Laccase ; Trametes versicolor ; Polycyclic aromatic hydrocarbons ; Oxidation ; C– ; C coupling ; Site-directed mutagenesis
• 刊名：Archives of Biochemistry and Biophysics
• 出版年：2008
• 出版时间：1 June 2008
• 年：2008
• 卷：474
• 期：1
• 页码：213-219
• 全文大小：562 K

文摘

The laccase genes lcc, lccβ, lccγ and lccδ encoding four isoenzymes from Trametes versicolor have been cloned and expressed in Pichia pastoris. Biochemical characterization allowed classification of these laccases into two distinct groups: Lcc and Lccβ possessed higher thermal stability, but lower catalytic activity towards 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) compared to Lccγ and Lccδ. Activities of the laccases were quite different as well. Laccase Lccδ showed highest phenolic C–C coupling activity with sinapic acid, but lowest oxidizing activity towards polycyclic aromatic hydrocarbons (PAHs). Highest activity towards PAHs was observed with Lccβ. After 72 h, more than 80 % of fluorene, anthracene, acenaphthene and acenaphthylene were oxidized by Lccβ in the presence of ABTS. Investigation of the structural basis of the different activities of the laccases demonstrated the impact of positions 164 and 265 in the substrate binding site on oxidation of PAHs.