Extracellular laccase from Monilinia fructicola: isolation, primary characterization and application

Abstract

Laccases are enzymes belonging to the family of blue copper oxidases. Due to their broad substrate specificity, they are widely used in many industrial processes and environmental bioremediations for removal of a large number of pollutants. During last decades, laccases attracted scientific interest also as highly promising enzymes to be used in bioanalytics. The aim of this study is to obtain a highly purified laccase from an efficient fungal producer and to demonstrate the applicability of this enzyme for analytics and bioremediation. To select the best microbial source of laccase, a screening of fungal strains was carried out and the fungus Monilinia fructicola was chosen as a producer of an extracellular enzyme. Optimal cultivation conditions for the highest yield of laccase were established; the enzyme was purified by a column chromatography and partially characterized. Molecular mass of the laccase subunit was determined to be near 35 kDa; the optimal pH ranges for the highest activity and stability are 4.5–5.0 and 3.0–5.0, respectively; the optimal temperature for laccase activity is 30°C. Laccase preparation was successfully used as a biocatalyst in the amperometric biosensor for bisphenol A assay and in the bioreactor for bioremediation of some xenobiotics.

Proteomic Studies to Understand the Mechanisms of Peach Tissue Degradation by Monilinia laxa

“… De Miccolis Angelini et al (2018) described a laccase2 ( Monilinia_025960 ortholog) one of the most differently expressed genes in M. laxa , although their possible plant-pathogen role had not been studied in Monilinia spp. its possible biotechnological applications had been considered ( Bao et al, 2012 ; Demkiv et al, 2020 ). Proteins involved in the modification of fungal cell walls played an essential role in growth, survival, and also plant-fungi interaction in phytopathogens ( Free, 2013 ; Geoghegan et al, 2017 ; Patel and Free, 2019 ).…”

Screening of Novel Laccase Producers—Isolation and Characterization of Cold-Adapted Laccase from Kabatiella bupleuri G3 Capable of Synthetic Dye Decolorization

“…In the case of laccase produced by Monilinia fructicola, it was the day 2 of culture. In the presence of 1 mM Cu 2+ and Mg 2+ ions, a 5-fold increase in the activity of this enzyme was observed in the post-culture liquid compared to the culture without inducers [39]. The obtained level of K. bupleuri laccase activity after induction with copper (II) ions was still too low to be able to test the potential of the selected oxidoreductase.…”

“…A slightly higher value, pH 5.0, was noted for A. pullulans laccases [51] and for Thielavia sp. [74]; and pH 4.5-5.0 for the laccases from M. fructicola [39]. A much more acidic operating environment is preferred by laccase produced by Coprinopsis cinerea Okayama 7, with its highest activity towards ABTS is recorded at pH 2.5 [71].…”

“…The pH-stability of laccases also varies and depends on the manufacturer. Thus, laccases from M. fructicola [39], C. lagenarium [16], T. hirsuta [29] and Thielavia sp. [74] are stable in an acidic pH range of 3.0-5.0, whereas the laccase from Trametes sp.…”

“…Moreover, G3 laccase is the first enzyme of its kind for which activity was also observed at 0 and 4 • C. Most of the known multicopper oxidases are thermophilic enzymes characterized by high optimal operating temperatures, and the fungal laccases from the literature usually have T opt of 50-60 • C [29,35,45,[71][72][73][74]. Homologues with lower T opt were also described, e.g., laccases from A. pullulans [51,52], Monilinia fructicola [39], Aureobasidium melanogenum [75], V. volvacea V14 [31] and Cerrena sp. HYB07 [72] operate at high activity at 30-45 • C, similarly to the K. bupleuri laccase reported in this study.…”