Дослідження ґрунтових лаказ у ХХІ ст.: основні напрями та перспективи

• Видавець: M.M. Gryshko National Botanical Garden of the NAS of Ukraine
• Дата: 2019
• Автор: Zakrasov, A.V.
• Формат: Стаття
• Мова: English
• Опубліковано: M.M. Gryshko National Botanical Garden of the NAS of Ukraine 2019
• Онлайн доступ: https://www.plantintroduction.org/index.php/pi/article/view/1534

Laccases (benzodiol: oxygen oxidoreductases, EC 1.10.3.2) belong to the so-called blue-copper oxidase family and are coppercontaining enzymes that are involved in oxidative processes by catalyzing the oxidation of various compounds with molecular oxygen, including o- and w-diphenols, aminophenols, polyphenols, polyamines, aryl diamines, phenolic substructures of lignin, and also some inorganic ions. The physiological functions of laccases are diverse: participation in the formation of pigments and the formation of fruiting bodies of fungi, detoxification of phenols, catalysis of the oxidation of non-phenolic lignin units (C4-esterified) to radicals. Laccase activity increases due to the introduction of Cu2+, Mg2+ and Na+, but is strongly inhibited by Fe2+, Ag+, l-cysteine, dithiothreitol and NaN3. In the lower soil layers, the activity of laccase shows a significant increase when supplied with mineral N, the addition of compost leads to increased activity in the surface layer. The prospects for the practical use of oxidases increased after the discovery of the possibility of enhancing their action using redox mediators, which are substrates of these enzymes, during the oxidation of which highly redox potential and chemically active products are formed. Biocatalytic systems created by nano-technologies (bacterial nanocellulose, carbon nanotubes, magnetic nanoflowers etc.) increase the reaction efficiency by increasing the surface area and loading capacity, and reducing the mass transfer resistance. The effectiveness of immobilization is highly dependent on the process conditions, the properties of the enzyme and the material of the carrier. In particular, a clear correlation was established between the redox potential of the substrate and the efficiency of homogeneous catalysis. Of particular note is the effect of laccase on soil emissions of CO2 and other greenhouse gases. Participating in the polymerization of soluble phenols, they thereby contribute to humification, forming stable humic fractions that bind soil carbon. The data presented indicate that soil laccase is an important factor in the functionality of soil, but they need to be studied in more detail in order to understand the mechanisms that regulate their activity.