[Biodegradation of Cellulose-Containing Substrates by Micromycetes Followed by Bioconversion into Biogas].

The ability of micromycetes Trichoderma viride and Aspergillus terreus to decompose the cellulose-containing substrates was studied. Office paper and cardboard, as well as a paper mixture, were found to be the most hydrolyzable. The cellulolytic activity of T. viride was 2-3 times higher than that of A. terreus; the highest values of 0.80 and 0.73 U/mLwere obtained from office paper and the paper mixture, respectively. The micromycete cultivation conditions (composition of culture medium, sucrose cosubstrate addition, seeding method) and the conditions of the fungus biomass treatment for its subsequent bioconversion into biogas by anaerobic microbial communities were optimized. It was shown that pretreatment improves the efficiency of biogas production from lignocellulosic materials under seeding with microbial community of bovine animal manure. After pretreatment of the Jerusalem artichoke phytomass (stems and leaves) and its subsequent bioconversion into biogas by methanogenic community, the biogas yield was increased by 1.5 times.

[Properties of extracellular proteinase--an activator of protein C in blood plasma formed by Aspergillus ochraceus].

The properties of an extracellular proteinase activating plasma protein C isolated from the culture supernatant of A. ochraceus VKM F-4104D have been studied. This enzyme demonstrated a substrate specificity absent of hydrolyzing activity toward chromogenic proteinase substrates. On the basis of inhibitory analysis, the protein C-activating proteinase from A. ochraceus VKM F-4104D appeared to be a serine proteinase, together with that isolated from the venom of Agkistrodon contortrix contortrix. The isolated enzyme was a nonglycosylated protein with a molecular weight of about 33 kDa, pI 6.0 with an observed optimal activity under a pH of 8.0-9.0 and 37°C. A comparison of the properties of the protein C-activating proteinase formed by A. ochraceus and the enzyme derived from the venom of Agkistrodon contortrix contortrix demonstrated a similarity in their properties; however, proteinase from the micromycete appeared to be in the nonglycosylated state and possessed the ability to hydrolyze the chromogenic plasmin substrate H-D-Val-Leu-Lys-pNA.

[Solid-State and membrane-surface liquid cultures of micromycetes: specific features of their development and enzyme production (a review)].

Specific features in the development of micromycetes, typical mechanisms of their enzyme production, and conditions providing for an increase in enzyme secretion by the microscopic fungi in solid-state (on natural substrates and inert carriers) and membrane-surface liquid cultures are considered. The prospects and advantages of these fermentation methods for the production of extracellular enzymes are discussed and compared with submerged cultures.

[Effect of extracellular proteases of micromycetes of the genus Aspergillus on proteins of haemostasis system].

Screening of the genus Aspergillus micromycetes for secretion of extracellular proteolytic enzymes, capable of acting on human proteins of the hemostatic system, has been conducted. The ability of extracellular proteases of Aspergillus to cleave specific proteins of the hemostatic system chromogenic peptide substrates, as well as activate a series of proenzymes (protein C, factor X and prothrombin) has been found. The ability of extracellular proteases of micromycetes activate X factor of human blood plasma was first shown at the first time.

[Production of extracellular proteinases (protein C activators in blood plasma) by the micromycete Aspergillus ochraceus during submerged and solid-state cultivation].

The conditions for the submerged and solid-state cultivation of the micromycete Aspergillus ochraceus VKM F-4104D, producing extracellular proteinases that activate protein C in human blood plasma, were optimized. It is shown that the protein C-activating activity of the micromycete in a solid-state culture was 1.5-3.5 times higher than in a submerged culture (as calculated per milliliter of culture medium). Among the extracellular proteins secreted by A. ochraceus VKM F-4104D during submerged and solid-state cultivation, a protein C-activating proteinase with a pI of 6.0-6.3 was identified.

[Aspergillus ochraceus myxomycetes produce extracellular proteinases--protein C activators of blood plasma].

Natural isolates of Aspergillus ochraceus myxomycetes from soil and plant remains from various regions have been screened. The isolated strains were characterized by similar cultural and morphological features and an identical nucleotide sequence in the ITS1-5,8S-ITS2 region of rDNA. The ability of the extracellular proteinases of A. ochraceus myxomycetes to activate protein C of blood plasma has been established. Differences are revealed in the accumulation of proteinases activating protein C and proteinases with thrombin- and plasmin-like activities in the growth dynamics of producers.