A novel fungal laccase from Sordaria macrospora k-hell: expression, characterization, and application for lignin degradation

作者：Yang, Xiaorong^*; Gu, Chenguang; Lin, Ying^*

来源：Bioprocess and Biosystems Engineering, 2020, 43(7): 1133-1139.

DOI：10.1007/s00449-020-02309-5

• Laccase
• Lignin degradation
• Sordaria macrospora k-hell
• Characterization

The laccase has the ability to oxidize substituted phenols and the water is the sole byproduct, thus it has been employed to remove and/or modify the lignin in lignocellulosic material. A putative laccase gene, LacSM, from Sordaria macrospora k-hell was screened by a genome mining approach. Then, it was cloned and highly expressed in Escherichia coli. The molecular weight of recombinant LacSM was similar to 67 kDa. The optimal pH values for the LacSM oxidation of guaiacol, syringaldazine, 2,6-dimethoxyphenol, and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) were 6, 7, 5, and 5, respectively. The optimal activity of laccase was observed at 60, 55, 55, and 50 degrees C for four respective substrates. LacSM remained stable at pH 5-8 and thermostable at 60 degrees C with guaiacol as the substrate. 1 mM K+, Na+, or Mn2+ ions slightly stimulated laccase activity. In addition, LacSM was moderately tolerant to the Cl- ion and showed an ability to remove and/or modify lignin. Thus, LacSM was a potential candidate for industrial applications, such as lignin degradation of lignocellulosic biomass.

• 单位
  y; 6