The process of pit formation in plants still has various questions unaddressed and unknown, which opens up many interesting and new research opportunities. The aim of this work was elucidation of the mechanism for the formation of bordered pits of the spruce (Picea abies (L.) Karst.) tracheid with exosomes participation and mechanical deformation of the cell wall. Sample sections were prepared from spruce stem samples after cryomechanical destruction with liquid nitrogen. The study methods included scanning electron microscopy and enzymatic treatment. Enzymatic treatment of the elements of the bordered pit made it possible to clarify the localization of cellulose and pectin. SEM images of intermediate stages of bordered pit formation in the radial and tangential directions were obtained. An asynchronous mechanism of formation of bordered-pit pairs in tracheids is proposed. The formation of the pit pair begins from the side of the initiator cell and is associated with enzymatic hydrolysis of the secondary cell wall and subsequent mechanical deformation of the primary cell walls. Enzymatic hydrolysis of the S₁ layer of the secondary cell wall is carried out by exosome-delivered endoglucanases.

Microbial dehydrogenase activity can help to determine the oxidizing capacity of activated sludge. Here we propose an innovative and automated express-method based on rapid determination of dehydrogenase activity. The measurement is based on the rate of methylene blue reduction by living microbial cells in suspension. A single analysis takes 10 min. The method was adapted for biofilms immobilized on the floating carriers of industrial bioreactors and the kinetics of biological oxidation by activated sludge and biofilms was compared. New parameters were proposed to characterize the biological oxidation under low oxygen levels. The obtained make it possible to quickly determine the dehydrogenase activity of activated sludge and biofilms and promptly monitor the effectiveness of industrial biological wastewater treatment.

A novel chi19 gene encoding the chitinase, belonging to the glycosyl hydrolase family 19 from the predatory plant Drosera capensis is cloned and expressed

Представлен аналитический обзор ферментных технологий, предназначенных для использования в целлюлозно-бумажном производстве (ЦБП). Высокая специфичность, экологическая безопасность ферментов делают их привлекательными реагентами для целлюлозно-бумажного производства. Ксиланазы, целлюлазы, липазы, эстеразы, амилазы, пектиназы рекомендуются или уже используются при производстве различных волокнистых полуфабрикатов. Введение в технологические процессы ферментов способствует селективному разрушению отдельных компонентов, что оказывает положительное влияние на состав технологических потоков и сточных вод, улучшает экологическую безопасность производства. Отдельные виды ферментов рекомендуются для микробиологического контроля образования биопленок, очистки сточных вод и обработки образующихся осадков. Ферментативные методы обеспечивают высокочувствительное и селективное определение различных веществ.