MORPHOLOGICAL AND CULTURAL, PHYSIOLOGICAL AND BIOCHEMICAL PECULIARITIES OF MICROMYCETES STRAINS INCLUDING IN THE COMPOSITION OF TRICHODERMA HARZIANUM 128 ASSOCIATION

Objective. Screen the active cellulolytic strains of Trichoderma micromycetes, investigate their morphological and cultural, physiological and biochemical properties for further use in the composting of organic substrates as a straw destroyer. Methods. Microbiological, biochemical, statistical. Results. 150 isolates of cellulolytic microscopic fungi of the genus Trichoderma were obtained from semi-decomposed straw. Among isolated fungi, the most active influence on the destruction of cellulose is typical for the association of micromycetes Trichoderma sp. 128. The components of the association (Trichoderma sp. 128/1 and Trichoderma sp. 128/2, respectively) differ in their nature of growth in the digest medium, colouring of colonies, and cellulolytic activity. Under simultaneous cultivation of the association components in a medium where the only source of carbon is filter paper or straw, higher effect was observed compared with than their separate cultivation. The selected association provides a degree of straw decomposition of up to 33 % over a period of 21 days, which exceeds the activity of the known cellulolytic strain Trichoderma harzianum F-2455. By morphological and cultural, physiological and biochemical properties, the components of the fungal association have been identified as Trichoderma harzianum 128/1 and T. harzianum 128/2 (association – Trichoderma harzianum 128, respectively). Under the study of virulence of microorganisms on the model of white mice, it was established that the association components are not pathogenic for warm-blooded animals, which allows the association to be used in the production. Conclusion. Active cellulolytic association of micromycetes which includes two strains has been selected. The association is identified as Trichoderma harzianum 128. The use of the association of micromycetes can be promising when composting organic matter, in order to accelerate its mineralization.

Draft Genome Sequence of the Cellulolytic Strain Clostridium sp. Bc-iso-3 Isolated from an Industrial-Scale Anaerobic Digester

Clostridium sp. Bc-iso-3 is a cellulolytic strain isolated from a Swedish industrial-scale biogas digester. Here, we present the draft genome sequence of this strain, which consists of four contigs with a total length of 4,327,139 bp and an average coverage of 312.97×.

Ruminococcus champanellensis sp. nov., a cellulose-degrading bacterium from human gut microbiota

A strictly anaerobic, cellulolytic strain, designated 18P13T, was isolated from a human faecal sample. Cells were Gram-positive non-motile cocci. Strain 18P13T was able to degrade microcrystalline cellulose but the utilization of soluble sugars was restricted to cellobiose. Acetate and succinate were the major end products of cellulose and cellobiose fermentation. 16S rRNA gene sequence analysis revealed that the isolate belonged to the genus Ruminococcus of the family Ruminococcaceae. The closest phylogenetic relative was the ruminal cellulolytic strain Ruminococcus flavefaciens ATCC 19208T (<95 % 16S rRNA gene sequence similarity). The DNA G+C content of strain 18P13T was 53.05±0.7 mol%. On the basis of phylogenetic analysis, and morphological and physiological data, strain 18P13T can be differentiated from other members of the genus Ruminococcus with validly published names. The name Ruminococcus champanellensis sp. nov. is proposed, with 18P13T ( = DSM 18848T = JCM 17042T) as the type strain.

Cellulase, Clostridia, and Ethanol

SUMMARY Biomass conversion to ethanol as a liquid fuel by the thermophilic and anaerobic clostridia offers a potential partial solution to the problem of the world's dependence on petroleum for energy. Coculture of a cellulolytic strain and a saccharolytic strain of Clostridium on agricultural resources, as well as on urban and industrial cellulosic wastes, is a promising approach to an alternate energy source from an economic viewpoint. This review discusses the need for such a process, the cellulases of clostridia, their presence in extracellular complexes or organelles (the cellulosomes), the binding of the cellulosomes to cellulose and to the cell surface, cellulase genetics, regulation of their synthesis, cocultures, ethanol tolerance, and metabolic pathway engineering for maximizing ethanol yield.