Changes in the Composition and Physiological and Biochemical Properties of Fungi during Passage through the Digestive Tract of Earthworms.

It was established that the biomass of fungal mycelium decreased by 30-50% during passage through the in- testine of the Aporrectodea caliginosa and Lumbricus terrestris earthworms, while its content in empty intes- tines was 40-60% less than in the soil. It was found that the amount of mycelium increases again in three-day-old coprolites due to the rapid growth of the species. It was demonstrated that the physiological activity of fungi (estimated according to the time of the appearance of colonies on the medium and probability of propagation) is lower in the intestine content, digestive tract, and fresh excrement of the worms than in the soil.

[Sorption of humic acids by bacteria].

Capacity for sorption of humic acid (HA) from water solutions was shown for 38 bacterial strains. Isotherms of HA sorption were determined for the cells of 10 strains. The bonding strength between the cells and HA (k) and the terminal adsorption (Q(max)) determined from the Langmuir equation for gram-positive and gram-negative bacteria were reliably different.

[Earthworms as modifiers of the structure and biological activity of humic acids].

Passage of humic acids (HAs) through the digestive tract of the earthworm, Eiseniafetida andrei, resulted in a decrease in molecular masses of the HAs. The effect of earthworm-modified HAs on individual bacteria and on bacterial communities as a whole is different from the effect of native HAs. Modified HA probably induces and regulates microbial successions in soils and composts in a different manner than the native HA, suppressing or stimulating different groups of microorganisms.

Effect of the earthworms Lumbricus terrestris and Aporrectodea caliginosa on bacterial diversity in soil.

Earthworms ingest large amounts of soil and have the potential to radically alter the biomass, activity, and structure of the soil microbial community. In this study, the diversity of eight bacterial groups from fresh soil, gut, and casts of the earthworms Lumbricus terrestris and Aporrectodea caliginosa were studied by single-strand conformation polymorphism (SSCP) analysis using both newly designed 16S rRNA gene-specific primer sets targeting Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Bacteroidetes, Verrucomicrobia, Planctomycetes, and Firmicutes and a conventional universal primer set for SSCP, with RNA and DNA as templates. In parallel, the study of the relative abundance of these taxonomic groups in the same samples was performed using fluorescence in situ hybridization.

[Response of bacteria to earthworm surface excreta].

Response of bacteria to the surface excreta of the Aporrectodea caliginosa earthworm was studied. The excreta were obtained by a 1 h incubation of the earthworms in petri dishes with subsequent collection of the slime. Both inhibition and stimulation of growth were revealed, as well as suppression of the respiratory activity of some bacterial species treated with A.

[Reaction of microorganisms to the digestive fluid of the earthworms].

The reaction of soil bacteria and fungi to the digestive fluid of the earthworm Aporrectodea caliginosa was studied. The fluid was obtained by centrifugation of the native enzymes of the digestive tract. The inhibition of growth of certain bacteria, spores, and fungal hyphae under the effect of extracts from the anterior and middle sections of the digestive tract of A.

[Interrelationships between yeast fungi and collembolans in soil].

The possibility of feeding on green and newly fallen leaves of the small-leaved lime Tilia cordata was studied for the collembolans Protaphorura armata and Vertagopus pseudocinereus. Young leaves grown under sterile conditions and almost free of yeast fungi were established to be toxic to the collembolan V. pseudocinereus: feeding on them led to the death of the animals.

[Morphometric analysis of bacteria associated with soil Myriapoda].

Scanning electron microscopy revealed that the average cell size of bacteria associated with the digestive tract of soil Myriapoda was 0.65 microm in diameter, 1.36 microm in length, and 0.

[Regulation of the biomass and activity of soil microorganisms by microfauna].

Microcosm experiments showed that the microbial biomass and the respiration activity in soil were regulated by nematodes. Depending on nematode number and plant residue composition, the trophic activity of nematodes can either stimulate or inhibit microbial growth and respiration as compared to soil containing no nematodes. The stimulating effect was observed when nitrogen-free (starch) or low-nitrogen (wheat straw, C:N = 87) organic substrates were applied.

[External instrumental fixation of the spine in the treatment of spinal diseases and injuries].

The authors analyze the results of treatment of 358 patients with specific and nonspecific spondylitis and with aftereffects of unstable fractures of the vertebrae proper, who have been operated on the spine destruction or instability area with the extrafocal fixation of the operated on segments by means of the Byzov apparatus. This method has yielded good clinical and functional results, effected the stability of the anterior and posterior portions of the operated on sites; it permits early (starting from the 5th-10th day postoperation) exercise of the patients, helps normal functioning of the body organs and systems, and activates the repair processes in the operated on sites. The incidence rate of the postoperative complications drops drastically, the patients rapidly recover their working abilities, and the invalidism is more rare.

[Structure of a primed microbial community as an integral method of evaluating the microbiologic state of soil].

The paper describes a laboratory method of initiated microbial cenosis which makes it possible to evaluate the microbiological state of soil and to predict its change under the action of various anthropogenic factors. To this end, the structure and characteristics of a microbial cenosis initiated by a substrate are studied using a scanning electron microscope in combination with classical techniques of microbiology: the actual predominance and proportions of individual microbial groups (bacteria, actinomycetes, fungi, algae, protozoa and microscopic invertebrates); the interaction and interrelation between individual microbial populations in the cenosis; the biological properties of predominating microorganisms; the ratio between active and resting forms; the rate and character of growth of individual microbial populations in the cenosis and their succession. All these indices taken together may serve as a criterion for integral evaluation of the effect produced by various physico-chemical factors on the microbiological state of soil.