Irpex lacteus, a white-rot fungus with biotechnological potential--review.

White-rot fungi that are efficient lignin degraders responsible for its turnover in nature have appeared twice in the center of biotechnological research - first, when the lignin degradation process started being systematically investigated and major enzyme activities and mechanisms involved were described, and second, when the huge remediation potential of these organisms was established. Originally, Phanerochaete chrysosporium became a model organism, characterized by a secondary metabolism regulatory pattern triggered by nutrient (mostly nitrogen) limitation. Last decade brought evidence of more varied regulatory patterns in white-rot fungi when ligninolytic enzymes were also abundantly synthesized under conditions of nitrogen sufficiency. Gradually, research was focused on other species, among them Irpex lacteus showing a remarkable pollutant toxicity resistance and biodegradation efficiency. Systematic research has built up knowledge of biochemistry and biotechnological applicability of this fungus, stressing the need to critically summarize and estimate these scattered data. The review attempts to evaluate the information on I. lacteus focusing on various enzyme activities and bioremediation of organopollutants in water and soil environments, with the aim of mediating this knowledge to a broader microbiological audience.

Implication of Dichomitus squalens manganese-dependent peroxidase in dye decolorization and cooperation of the enzyme with laccase.

Three new chromatographic forms of Dichomitus squalens manganese-dependent peroxidase (MnP) were isolated from wheat-straw cultures using Mono Q and connective interaction media (CIM) fast protein liquid chromatography. Enzymes revealed identical molar mass of 50 kDa (estimated by SDS-PAGE) and pI values of 3.5, however, they varied in Km values obtained for Mn2+ oxidation. The addition of wood and straw methanol extracts to the cultures showed that the production of MnPs in wheat-straw cultures was influenced rather by the type of cultivation than by phenolic compounds from lignocellulosic material which induced laccase production. The purified CIM1 MnP was able to decolorize selected azo and anthraquinone dyes more rapidly than laccase Lc1. In vitro dye decolorization showed a synergistic cooperation of MnP and laccase. In the case of CSB degradation MnP prevented from the production of a differently colored substance that could be produced after CSB degradation by laccase-HBT system.