Doklady Biological Sciences最新文献

The cranial and mandibular fragments of the medium-sized canid from the Early Pleistocene locality of Taurida cave (about 1.8-1.5 Ma) in Crimea are described and included in the hypodigm of the species Canis etruscus Forsyth Major, 1877, a common member of the Late Villafranchian fauna of the Circum-Mediterranean region. This species is reported for the first time from the Northern Black Sea region. The discovered evidence reinforce previous published idea regarding the periodically use of the Taurida cave by canids and other large predators as a den and shelter.

Significant changes in lactobacillus-derived extracellular membrane vesicles, which transfer lipids, polysaccharides, proteins, and nucleic acids, were for the first time observed to accompany the development of resistance to antibiotics (amoxicillin and clarithromycin) in vitro in the probiotic strain Lactiplantibacillus plantarum 8p-a3. The changes occur together with large-scale genome rearrangements, changes in the profile of phenotypic sensitivity to antimicrobials of various groups, and evolution of virulence. Changes in vesicles affected their structure, composition, and activity against biofilms of opportunistic bacteria. The data provide for a better understanding of the molecular mechanisms of microbial survival under selective pressure of antimicrobials, the functional potential of probiotic vesicles, and probiotic safety assessments.

The work contains a comparative analysis of methods for storing pure cultures of macrofungi. The study used 20 species of macrofungi from various taxonomic and ecological-trophic groups. Storage was carried out using five methods: serial subculturing, storage under a layer of distilled water and three cryopreservation protocols: a protocol using blocks of agar medium, a "perlite protocol," and a "grain protocol." For the selected cryostorage methods, various cryoprotective compounds (glycerol, trehalose) were used. Radial growth rate was used as a criterion for the state of crops. The values of the radial growth rate obtained immediately after isolation of the pure culture were chosen as the control. It has been shown that the most favorable for preserving the physiological activity of cultures are the storage method under a layer of distilled water, "perlite" and "grain" cryopreservation protocols.

We tested whether one of the consequences predicted for alien plant invasion by the mutualism disruption hypothesis was true in the case of the ash-leaved maple Acer negundo L. The study aimed to determine whether the occurrences of mycorrhizal and nonmycorrhizal herbs varied similarly or differently in communities with varying degrees of A. negundo dominance. The analysis included the results of 78 vegetation descriptions carried out in Belarusian Polesia, the Middle Volga region, and the Middle Urals. Communities with or without A. negundo dominance were described in each region. The mycorrhizal status of plant species was determined using the FungalRoot Database. Species that are more likely to form arbuscular mycorrhiza were found to occur less frequently in A. negundo thickets. On the contrary, a higher probability of the nonmycorrhizal status was associated with a lower frequency of detection in A. negundo thickets. Therefore, the occurrence of arbuscular mycorrhizal herbs was found to selectively decrease in communities dominated by A. negundo.

The PCID2 protein is a component of the eukaryotic TREX-2 complex, which is responsible for mRNA export from the nucleus into the cytoplasm. We have previously shown that Drosophila melanogaster PCID2 is involved in specific mRNA recognition and identified the key amino acids responsible for its interaction with the ras2 RNA. In this work, point mutations of the amino acids were shown to disrupt the PCID2 interaction with cell RNAs and to distort the export of polyA-containing mRNAs from the nucleus into the cytoplasm in Drosophila cells.

The Tip-Tugai Cave (52°59'28.6″ N, 57°00'22.3″ E) is described as a new site with cave hyena Crocuta spelaea fossils. The bone-bearing layer was dated to marine isotope stage (MIS) 3 based on the species composition of the fauna of large and small mammals. Finds of abundant remains of cave hyenas of different ages and bones of large herbivores with hyena gnaw marks indicated that the Tip-Tugai Cave was used as a hyena den in the Late Pleistocene. This is the first cave hyena den described in the Urals.

A new genus and species of fossil swallows, Miochelidon eschata gen. et sp. nov., are described from the Lower Miocene of the Baikal region. This is the only Miocene representative of Hirundinidae and the oldest fossil record of the group. The coracoid of Miochelidon combines generalized and specialized features, suggesting a basal position in the family for the genus. The ulna has a more advanced morphology, like in modern swallows. The find indicates a widespread distribution of basal swallows in the Early Miocene.

The wild soybean Glycine soja Sieb. et Zucc. is an ancestor of the cultivated soybean Glycine max (L.) Merr. and a source of many valuable genes missing in the G. max genome, including genes that determine stress resistance to adverse environmental factors. Biochemical parameters (protein, oil, ascorbic acid, carotene, higher fatty acids, and specific activities and multiple forms of enzymes of the oxidoreductase and hydrolase classes) were studied in five G. soja accessions from the collection of the All-Russian Institute of Soybean (КА-1413, КА-342, КBl-29, КBl-24, and Kеl-72). The accessions provide unique natural gene banks. Wild seeds were collected in three districts (Arkharinskii, Blagoveshchensk, and Belogorskii) of Amur Oblast. Based on superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), ribonuclease (RNase), acid phosphatase, esterase, and amylase (AML) activities and biochemical parameters of seeds, the G. soja accession KA-1413 was found to have higher contents of protein, oleic acid, and linolenic acid; a lower polyphenol oxidase specific activity; and higher activities of SODs, esterases, and RNases. The accession KA-1413 was therefore recommended to use as a source of dominant genes in breeding to increase the adaptive potential of new soybean varieties. A higher heterogeneity of multiple forms was observed for SOD, AML, RNase, and esterase, which can provide markers of adaptation to environmental conditions.

A mandible fragment of Acinonyx pardinensis (Croizet et Jobert, 1828) is described from the Early Pleistocene locality in the Taurida cave (Crimea, Late Villafranchian, about 1.8-1.5 Ma). This is the first discovery of the genus Acinonyx in the Pleistocene of Crimea. Along with other felids, such as Homotherium, Megantereon, Panthera, Lynx, and Puma, cheetahs were typical representatives of the Late Villafranchian faunas of Eurasia. In the Taurida locality, Acinonyx pardinensis is co-occurred with Homotherium crenatidens, Megantereon adroveri, and Lynx issiodorensis.