Improved Efficiency in Screening for Lignin-Modifying Peroxidases and Laccases of Basidiomycetes

Abstract

Abstract:Background: Wood rotting white-rot and litter-decomposing basidiomycetes form a huge reservoir of oxidative enzymes, needed for applications in the pulp and paper and textile industries and for bioremediation.Objective: The aim was (i) to achieve higher throughput in enzyme screening through miniaturization and automatization of the activity assays, and (ii) to discover fungi which produce efficient oxidoreductases for industrial purposes.Methods: Miniaturized activity assays mostly using dyes as substrate were carried out for lignin peroxidase, versatile peroxidase, manganese peroxidase and laccase. Methods were validated and 53 species of basidiomycetes were screened for lignin modifying enzymes when cultivated in liquid mineral, soy, peptone and solid state oat husk medium.Results: Manganese peroxidases were the most common enzymes produced by 96% of the species. They typically had acidic pH optima, although Hyphodontia sp., Pleurotus pulmonarius and Trametes ochracea produced enzymes highly active at pH 7. Versatile peroxidase was produced by 66% of the fungi with efficient production from Phlebia radiata, P. pulmonarius and Galerina marginata. Novel lignin peroxidase producing fungi Cylindrobasidium evolvens and Daedaleopsis septentrionalis were found among the 26% of the species showing here lignin peroxidase production. Laccase was shown in 92% of the species. Several fungi produced laccase active at pH 7, which is noteworthy because usually laccases of white-rot fungi are efficient and relevant for many industrial applications. Conclusion:Automated screening allowed us to monitor many specific enzyme activities and extend the range of assay conditions from relatively small fungal cultivation sample volumes.

Differential responses of carbon‐degrading enzyme activities to warming: Implications for soil respiration

“…Indeed, several studies suggest that warming‐induced changes in soil microbial community composition cause differential responses of cellulase and ligninase activities (Deangelis et al., ; Pold, Grandy, Melillo, & Deangelis, ). This explanation is also consistent with studies showing that fungi are main contributors to ligninase production (De Gonzalo et al., ; Kinnunen, Maijala, Jarvinen, & Hatakka, ) and that experimental warming increases fungal abundance (A'bear, Jones, Kandeler, & Boddy, ; Delarue et al., ). However, warming may also directly or indirectly cause physiological adaptation of soil microorganisms to increase enzyme production (Manzoni, Taylor, Richter, Porporato, & Gren, ; Nie et al., ; Schindlbacher et al., ), even when warming decreases total microbial biomass (Pold et al., ; Sistla & Schimel, ; Sorensen et al., ).…”

Physiological Peculiarities of Lignin-Modifying Enzyme Production by the White-Rot Basidiomycete Coriolopsis gallica Strain BCC 142

“…The production of LME by C. gallica 142 and the ratio of the individual enzymes, similar to other WRB [ 5 , 13 , 14 , 28 ] was clearly dependent on the lignocellulosic growth substrate and its concentration ( Table 3 , Figure 1 ). For example, sunflower oil cake provided maximum laccase activity of C. gallica 142, wheat straw promoted MnP secretion while mandarin peels increased the culture’s LiP expression.…”

Effects of Gadolinium and Tin to the Production of Oxidative Enzymes and the Growth of Five Basidiomycetous Fungi

“…Reactive Black 5 (RB5) is a specific substrate to test the activity of versatile peroxidase (VP), which oxidizes directly RB5 without mediators, and it can be seen as decolorization of RB5. This dye has been used to screen VP activity in a number of lignin degrading fungi [29]. Lignin peroxidase needs a redox mediator to oxidize this compound [2].…”