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The chronosequence of soils buried under constructions of different ages at the large (3.5 m in height and 74 m in diameter) Shumny Kurgan in the Krasnodar region has been studied. The kurgan was built sequentially by the people of Catacomb (28th–22nd centuries BC) and Srubnaya (15th–10th centuries BC) cultures and includes five constructions made of the material of local soils and anthropogenic admixtures. Each of the subsequent constructions overlapped the previous one and went beyond it, covering some additional space. This allows us to study a consecutive series of soils buried under the constructions. During the kurgan building (28th–10th centuries BC), the morphological and physicochemical properties of the soils changed: the content of organic matter and magnetic susceptibility increased, whereas the mixing up of the upper horizons by burrowing animals, the content of carbonates, and the exchangeable sodium percentage decreased. The direction of these changes in the properties of the materials of kurgan constructions over time agree with changes in the properties of corresponding buried soils. For the uneven-aged constructions of the kurgan, local soils were used, which had different properties at the stages of the construction. These soils occupied a significantly larger area than the kurgan, which increases the reliability of the study. Evolutionary changes in the properties of buried soils and earth materials of kurgan structures are indicative of the climatic trend during the long-term kurgan construction—an increase in atmospheric moistening and a decrease in the mean annual temperature from the Early Catacomb to Srubnaya cultures. An independent palynological analysis of buried paleosols confirms this conclusion about the tendency of climate changes. According to micromorphological data, the Early Catacomb time can be additionally characterized as an arid epoch, which manifested itself in soil cracking and accumulation of carbonates in the upper part of soil profiles. Based on the structure and properties of the kurgan, it is possible to identify technologies of the construction, which included tamping down of earthy material in dry and wet states; its mixing; and adding of river silt, charcoal, and bones. [ABSTRACT FROM AUTHOR]

Soils buried under archaeological monuments of the Bronze Age were studied on three test plots in Orenburg oblast, Stavropol krai, and Krasnodar krai. Kurgan 1 of burial mound (BM) Boldyrevo IV was built in two stages from the second quarter to the middle of the 4th millennium BC by the population of the Yamnaya culture of the early Bronze Age and included four earthen structures. Kurgan Essentukskii 1 was built in the second quarter of the 4th millennium BC (the early Maikop culture) and included four earthen structures. According to archaeological data, the mounds were built during several ten-year periods. In kurgan 1 of BM Beisuzhek 9, three constructions of different periods were identified: the first and second ones of the middle of the 2nd millennium BC (the Novotitorovskaya culture) and the third one of the beginning of the 2nd millennium BC (the Catacomb culture). Buried soils were studied under each kurgan structure, and pits of modern soils were laid outside each kurgan under similar topolithological conditions. A comparative analysis of the morphological and physicochemical properties of buried and modern soils of the chronoseries, as well as analysis of the palynological spectra from the upper horizons of these soils, were conducted. The processes of dehumification, carbonate accumulation, salinization, and alkalization of the studied soils became more intensive from the beginning to the end of the construction periods of all the mounds. The thickness of the humus horizon decreased, and the depth of occurrence of carbonates became closer to the day surface. The percentage of herbaceous plants in the plant association increased noticeably, and species typical for steppes appeared by the end of the construction period of the mounds. The analysis of paleosoil and palynological data shows that the regions studied were characterized by climatic changes—an increase in the mean annual temperatures and a decrease in the precipitation—in the Atlantic period of the Holocene (in the interval of 5500–5300 years ago) and in the Subboreal period of the Holocene (in the interval of 4500–3800 years ago). [ABSTRACT FROM AUTHOR]

As a result of whole genome sequencing of Bacillus subtilis BIM B-454D bacteria, it was shown that the genome is represented by a circular chromosome, 4 204 088 bp in size and three plasmids of 6990 bp, 6587 bp, and 6117 bp, respectively. The bacterial chromosome contains 4209 predicted genes. The taxonomic position of the bacteria was refined based on a comparison of the whole genome nucleotide sequence with a reference database. The strain B. subtilis BIM B-454D was reidentified as B. velezensis BIM B-454 D. Whole genome sequences were annotated and deposited in the public GenBank database under the numbers CP082262.1, CP082263.1, CP082264.1, and CP082265.1. The strain B. velezensis BIM B-454 D has a large number of genetic determinants that are responsible for economically valuable traits (antibacterial, antifungal, etc.). In the chromosome of the strain, 14 loci were identified that presumably encode genes for the synthesis of substances with antagonistic activities of various chemical natures: lipopeptides (surfactin and fengycin), polyketides (bacilen, difficidin, and macrolactin), bacillibactin siderophore, bacillisin dipeptide, the azole-containing peptide plantazolin. etc. The complete nucleotide sequence of the genome can serve as the basis for a detailed functional analysis of the practically significant properties of the microorganisms of the genus Bacillus. [ABSTRACT FROM AUTHOR]

The chronosequence of paleosols buried under structures of different ages in kurgan 1 of the Boldyrevo IV burial site in Orenburg oblast of Russia has been studied. The kurgan was built by representatives of the early (Repino) stage of the Yamnaya culture (about 5500 years ago) and included four successively made structures. According to archaeological data, the kurgan was built during decades, and 300-year-long interval was determined by radiocarbon dating. During that period, the morphological and physicochemical properties of buried soils changed: the lower boundary of the humus horizon became more tonguing; the degree of zooturbation of the profiles by burrowing animals increased; the organic carbon content dropped; and the contents of carbonate carbon, gypsum, and exchangeable sodium in the composition of exchangeable bases and magnetic susceptibility increased. The trend of changes in morphological properties, in the content of organic carbon and carbonates, and in magnetic susceptibility in the materials from the early to late kurgan structures correlated with that for the soils buried under them. Our study enables us to suggest that the climate during the analyzed period (the early stage of the Yamnaya culture) was more arid than the modern climate. The technological approaches used by the ancient builders for kurgan construction were revealed on the basis of data on the micromorphology and physicochemical properties of the materials of kurgan structures. [ABSTRACT FROM AUTHOR]

On the basis of the conducted paleosol, updated data on the direction of climate changes in the second half of the Holocene in the territory of the Kuban–Azov Lowland were obtained. The Atlantic optimum of the Holocene was replaced at the beginning of the third millennium BC by a short period of aridization. The 27/26th–22/21st centuries BC were the period of climate humidization followed by a warm and dry period in the 22/21st–16th centuries BC. In the Early Iron Age, from the second half of the 2nd century BC to the beginning of the 2nd century AD, a sharp aridization of the climate was reconstructed, the peak of which occurred at the turn of the millennium. Paleosols of the second half of the third millennium BC are characterized by the high humus content, leaching of carbonates from the upper horizons, impregnation with carbonate pseudomycelium of the profile, the presence of calcareous veins, disintegration or absence of calcareous nodules, and zooturbation of the profile. These features attest to humid climatic conditions. At the turn of the era, with the increasing aridity of the climate, the chernozems acquired features of more southern subtypes, but there was no change in soil types and subtypes during this period. [ABSTRACT FROM AUTHOR]

A short-term chronosequence of paleosols buried under different structures in the big Essentuksky 1 kurgan (North Caucasus) was studied. The kurgan was constructed in the second quarter of the 4th millennium BC (the Maikop culture). According to archaeological data, the kurgan construction continued for several decades. During this time, the morphological pattern and physicochemical properties of soils changed: the thickness of the humus profile and the content of organic carbon decreased, the contents of gypsum and carbonates increased, the zone of their accumulation shifted upwards the soil profile, and the transformation of carbonate pedofeatures took place. The most "arid" properties were found in the soil buried last in the studied chronosequence: the humus horizon of this soil is the lightest in color and has the lowest organic carbon content; the soil profile is most enriched in carbonates, which is manifested both at the macro- and microlevels of observation; the highest content of exchangeable sodium and magnesium is noted in the composition of exchangeable bases; a decrease in the magnetic susceptibility and a maximum in the gypsum content are observed in the second meter of the soil profile. During the construction of the kurgan, Calcic Chernozems (Loamic, Pachic) evolved into Haplic Calcisols (Loamic). A palynological analysis revealed a decrease in the area of forest vegetation and an increase in the share of herbaceous vegetation in the spectrum, including the appearance of steppe species and xerophytes in the region over the studied time. The climate of the studied time interval (the early stage of the Maikop culture in the North Caucasus) was arid and warmer than that at present. [ABSTRACT FROM AUTHOR]

Whole-genome sequencing of bacteria Bacillus velezensis BIM B-439D has revealed that its genome is represented by a single circular chromosome 3 978 954 bp in size and contains 3969 predicted genes. Chromosome has 10 conserved loci that determine the production of antimicrobial compounds of varying chemical nature, namely lipopeptides (surfactin, bacillomycin, fengycin), polyketides (bacillaene, difficidin/oxydifficidin, macrolactin), bacillibactin siderophore, dipeptide bacilysin, a protein/polyketide of uncertain composition, and amylocyclicin bacteriocin. Mutants with impaired surfactin synthesis have been obtained by direct mutagenesis; they were characterized by an increased production of bacillomycin and fengycin. The obtained mutants demonstrated high antimicrobial activity towards a number of bacterial and fungal pathogens (Penicillium expansum, Alternaria tenuis, Botrytis cinerea,Bipolaris sorokiniana), but they inhibited the growth of the Fusarium genus fungi to a lesser degree. [ABSTRACT FROM AUTHOR]

The published data and our own data on the mechanisms of the influence of microbial probiotics, prebiotics, and their combinations on the processes of symbiotic digestion have been considered and generalized. It is shown that the effects on an organism are associated with the enhanced metabolic activity of intestinal bacteria: stimulation of bacterial fermentation of carbohydrates and formation of short-chained fatty acids, an increase in the blotting capacity of the intestines due to elongation of villi and deepening of crypts, and a decrease in secretion of toxic proteolytic products (ammonia, phenols, thiols, indoles, etc.). It has been shown that a combination of probiotics and prebiotics enhances the biological efficiency of a complex preparation, which contributes to activation of carbohydrate, protein, and mineral metabolism. [ABSTRACT FROM AUTHOR]