Associations of cyanobacteria with actinomycetes are not investigated. The task was set in this work to study the biological aspects of coexistence of free-living cyanobacterium Anabaena variabilis with actinomycetes isolated from corraloid roots of Strangeria eriopus и Cycas micho- litzii and cyanobacterium Oscillatoria terebriformis (Ag.) Elenk. emend., which were isolated from the natural cyano-bacterial mat of Kamchatkan thermal spring, with actinomycetes, isolated from accumulating culture of cyanobacterium. Positive tropism of streptomycetes hyphes to the cya- nobacterial trichoms and cyanobacterium to streptomycetes were observed. Stimulation of growth of O. terebriformis in the associated culture with the streptomycete was marked. The increase of the fixation of nitrogen by A. variabilis and of photosynthetic activity by O. terebriformis in the associated culture with the streptomycete was marked. On this background associative interaction cyanobacteria with streptomycetes are positively discussing.

Seed inoculation with bacterial consortium was found to increase legume yield, providing a higher growth than the standard nitrogen treatment methods. Alfalfa plants were inoculated by mono- and binary compositions of nitrogen-fixing microorganisms. Their physiological and biochemical properties were estimated. Inoculation by microbial consortium of Sinorhizobium meliloti T17 together with a new cyanobacterial isolate Nostoc PTV was more efficient than the single-rhizobium strain inoculation. This treatment provides an intensification of the processes of biological nitrogen fixation by rhizobia bacteria in the root nodules and an intensification of plant photosynthesis. Inoculation by bacterial consortium stimulates growth of plant mass and rhizogenesis and leads to increased productivity of alfalfa and to improving the amino acid composition of plant leaves. The full nucleotide sequence of the rRNA gene cluster and partial sequence of the dinitrogenase reductase (nifH) gene of Nostoc PTV were deposited to GenBank (JQ259185.1, JQ259186.1). Comparison of these gene sequences of Nostoc PTV with all sequences present at the GenBank shows that this cyanobacterial strain does not have 100% identity with any organisms investigated previously. Phylogenetic analysis showed that this cyanobacterium clustered with high credibility values with Nostoc muscorum.

Effective sorbents based on nonwoven polymer materials have been synthesized for cleaning up oil and oil products spills from the water surface. The influence of structural characteristics of materials (a width of fabrics, a fiber diameter, a density of fiber packing in fabric) on their sorption capacity has been revealed. It has been shown that the materials based on polypropylene and polyether fibers exhibited the high sorption capacities in respect to oil and oil products.

Organic polymer materials (OPM) differing in sets of functional groups, fiber surface thickness and character, and density of fiber packing in fabric were synthesized. OPM were studied for assessing the possibility of their application as sorbents for oil spills in water bodies. The synthesized OPM were used for the creation of bio-hybrid materials as matrices for immobilization of bacteria of the genus Rhodococcus sp. capable of petroleum degradation. Actively dividing bacterial cells forming clusters were shown to be present at the surface of fibers. Active attachment of the cells to polymeric surface due to intrusion and/or excretion of extracellular biopolymeric matrix were detected. The modification of polymer sorbents was shown to influence bacterial immobilization. The peculiarity of growth and the specificity of cell morphology of bacterial culture were noted.

Associations of cyanobacteria and actinomycetes were formed experimentally from the cyanobacterium Anabaena variabilis ATCC 29413 and the streptomycetes isolated from apogeotropic roots of sago plants. Based on their phenotypic properties and the 16S rRNA gene sequencing, the streptomycetes were identified as representatives of Streptomyces pluricolorescens (strains 1 and 2). Cyanobacteria developing in monoculture and in association with an actinomycete were essentially different in their morphological and physiological-biochemical characteristics. In associations, cyanobacteria showed a higher (by tens of times) nitrogen-fixing activity compared to the monoculture and the morphological modifications of which were not observed in the monoculture (increase in cell size, increase in the portion of heterocysts among vegetative cells, appearance of the forms of unbalanced growth of cyanobacteria as giant, disc-shaped, curved, and rhomboid cells). At extremely low humidity (a(w) 0.50), associated cyanobacterial cells remained viable, whereas in the monoculture, chlorophyll decomposition and cells death occurred. The methods of high-resolution (H-1 600 MHz) nuclear magnetic resonance (NMR) and pulsed-gradient spin echo NMR revealed a fraction of mobile protons in lyophilized samples of the cyanobacterium-actinomycete association, which was evidence of the presence of free water. This fraction was not found in the lyophilized samples of cyanobacterial and streptomycete monocultures. The revealed differences can explain the survival of cyanobacterial cells in associations.

In experimental associations of Cyanoprokaryota and Actinomycetes isolated from natural algal-bacterial mats of hypersaline lakes of Crimea the specific interactions of Oscillatoria terebriformis (Ag.) Elenk. (Cyanoprokaryota) and Streptomyces odorifer (Rullman 1895) Waksman 1953 were revealed. They included: positive tropism of streptomyces hyphae to O. terebriformis; stimulation of photosynthetical activity of O. terebriformis in association with streptomyces comparing to monoculture; changing of antimicrobial properties of association in comparison with monocultures of Streptomyces and Oscillatoria. Functional role of actinomycetes in natural algal-bacterial mats is discussed.

The capacity of associations of cyanobacteria and actinomycetes to transform the structure of clay minerals (kaolin, vermiculite, mica, and montmorillonite) was experimentally revealed. First, easily weatherable vermiculite and biotite were transformed. The rate of transformation of micas to mixed-layered minerals depended on their structure: trioctahedral mica (biotite, the component of vermiculite) was changed much faster than dioctahedral mica (the component of kaolin). The lattices of all the phyllosilicates were altered (disordered and disaggregated) under the influence of the cyanobacterial-actinomycetal associations.

The transformation of the crystallochemical structure of phyllosilicates (vermiculite and biotite) under the impact of growing cyanobacterial and actinomycetal associations, as well as monocultures of cyanobacteria and actinomycetes, has been studied. The character of the mineral transformation depends on their crystallochemical structure and the type of biota. The most significant changes take place in the contact zone between minerals and microbial associations; the effect of microbial monocultures is smaller. The transformation of biotite proceeds via the stage of ordered mica-vermiculite (smectite) neoformation (rectorite); the destruction of vermiculite has been identified.

Associations of cyanobacteria with actinomycetes are not being investigated. The purpose of this study is to investigate the biological aspects of coexistence of the free-living Anabaena variabilis with actinomycetes isolated from apogeotropic roots of Strangeria eriopus and Cycas micholitzii; with the cyanobacterium Oscillatoria terebriformis (Ag.) Elenk. emend., which were isolated from the natural cyanobacterial mat taken from the Kamchatkan thermal spring; and with actinomycetes isolated from the accumulating culture of cyanobacterium. Positive tropism of actinomycete hyphae to cyanobacterial trichomes and that of the cyanobacterium to streptomycetes were observed. Stimulation of growth of O. terebriformis in the associated culture with the streptomycete was recorded. The increase of fixation of nitrogen by A. variabilis and of photosynthetic activity of O. terebriformis in the associated culture with the streptomycete was recorded.

The experimental modeling on cultivating the algobacterial association with cyanobacteria predominating was performed on a clayey substratum (kaolin) consisting of kaolinite (95%) with dioctahedral hydromica, chlorite, and quartz. The x-ray study registered the disturbance in the kaolinite and hydromica lattices and , the transformation of chlorite to the mixed-lattice chlorite-smectite formation.