Eurasian Journal of Applied Biotechnology

The Bacteroides fragilis toxin (bft) Gene: Its Role in Virulence, Regulation, and Disease

2025-05-23T10:03:37+05:00

Bacteroides fragilis can be divided into two different groups of strains: an enterotoxigenic strain (ETBF) that has a pathogenicity island and the Bacteroides fragilis toxin gene (bft) and a non-toxigenic strain (NTBF) that does not have a pathogenicity island and the bft gene. Recent studies have shown that there is a correlation between the presence of the bft gene in enterotoxigenic Bacteroides fragilis (ETBF) strains and various gastrointestinal disorders, including colorectal cancer and inflammatory bowel disease. Due to its ability to disrupt the intestinal epithelial barrier, promote chronic inflammation, and affect carcinogenesis, the presence and expression of bft significantly contribute to the pathogenicity of ETBF. This review provides an analysis of the genetic structure, allelic variants, and regulatory mechanisms of bft. A membrane protein vital to cell adhesion, E-cadherin, is disrupted by Bacteroides fragilis toxin, resulting in disruption of epithelial integrity and facilitating bacterial entry. BFT also stimulates important intracellular signaling pathways, including mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light chain enhancer of activated B cells (NF-kB). These signaling pathways significantly influence both cellular transformation and inflammatory responses. This review also highlights advances in diagnostic methods and innovative therapeutic approaches, such as the development of allosteric inhibitors that can block BFT activity. Although much has been learned about the regulation and function of the bft gene, there are significant gaps in understanding the environmental factors that lead to gene upregulation and its molecular interactions. Future research should aim to elucidate these mechanisms to facilitate the development of targeted therapies.

EFFICIENCY OF USING BIOLOGICAL PREPARATIONS AND MINERAL FERTILIZERS IN CULTIVATION OF SUGAR SORGHUM IN THE SOUTHERN REGIONS OF KAZAKHSTAN

2026-05-28T10:51:27+05:00

This article presents the results of studies on the influence of biological preparations and mineral fertilizers on the productivity of sugar sorghum cultivated in the southern regions of Kazakhstan. During a five-year field experiment (2019–2023), the complex effect of biologically active substances (Celeste Top, Gumi 20, Potassium Humate) and doses of nitrogen-phosphorus fertilizers (N₃₀P₃₀, N₆₀P₆₀, N₉₀P₉₀) on field germination, photosynthetic activity and green mass yield of sugar sorghum of the Kazakhstanskoye 20 variety was studied. It was found that the greatest effect is achieved with the combined use of Potassium Humate and fertilizers at a dose of N₉₀P₉₀, which provides a yield increase of 5.4 t/ha compared to the control. Optimal doses and combinations of biopreparations with mineral fertilizers have been determined, providing the maximum economic effect in the cultivation of sugar sorghum in arid conditions.

Evaluation of the immunobiological properties of an oral briquette rabies vaccine in foxes

2026-03-17T13:43:59+05:00

Rabies remains one of the most dangerous zoonotic infections maintained in natural reservoirs among wild carnivorous animals. Despite the high efficacy of inactivated vaccines in domestic animals, rabies control in wildlife requires the use of oral vaccines capable of providing mass immunization of naturally susceptible species. The aim of the present study was to evaluate the immunogenicity, safety, and protective efficacy of an oral briquetted rabies vaccine tested in naturally susceptible carnivorous animals. Clinically healthy rabies-seronegative foxes were used in the experiment. To assess immunogenicity, animals received a single oral administration of a briquetted vaccine containing a fixed rabies virus strain. Vaccine safety was evaluated using an increased dose (10 baits per animal). The dynamics of the humoral immune response were assessed using the mouse neutralization test and ELISA. Protective efficacy was determined by challenge infection with the CVS test strain. The results demonstrated that the vaccine was readily consumed by the animals and did not cause clinical adverse reactions or deviations from physiological norms. Vaccinated animals developed a pronounced humoral immune response, with mean virus-neutralizing antibody titers exceeding the protective level of 0.5 IU/ml and reaching peak values on day 21 post-immunization. Following challenge infection, all vaccinated animals survived and showed no clinical signs of rabies, whereas control animals developed the paralytic form of the disease with a fatal outcome. Thus, the obtained data demonstrate the high immunogenicity, safety, and protective efficacy of the oral briquetted rabies vaccine and confirm its potential for use in oral immunization programs targeting carnivorous wildlife species and the control of natural rabies foci.

BRYOPHYTE FLORA OF THE KARKARALY REGION (KARAGANDY REGION, KAZAKHSTAN): SPECIES COMPOSITION AND HABITAT DISTRIBUTION

2026-04-28T12:06:40+05:00

Bryophytes represent an important yet insufficiently studied component of terrestrial biodiversity in Central Kazakhstan. This study investigates the species composition and phylogenetic relationships of mosses in Karkaraly National Park (Karaganda Region), a forest–steppe enclave within the arid landscapes of the Kazakh Uplands. A total of 29 moss samples were collected and analyzed using an integrative approach combining microscopic morphological examination and molecular identification based on nuclear ribosomal ITS1 and ITS2 markers. Nine species belonging to seven families and four orders were identified, including Ceratodon purpureus, Syntrichia ruralis, Dicranum muehlenbeckii, Dicranum schljakovii, Polytrichum juniperinum, Polytrichum piliferum, Sanionia uncinata, Pylaisia polyantha and Abietinella abietina. Phylogenetic analysis using the Maximum Likelihood method confirmed species-level identification and revealed consistent clustering of samples within their respective genera. The detected assemblage reflects the ecological heterogeneity of the Karkaraly Mountains, where microclimatic variation supports both xerophytic and mesophilous moss species. This study represents one of the first integrative analyses combining morphological and molecular (ITS1 and ITS2) approaches to identify mosses in Central Kazakhstan. The results provide novel baseline data on species composition and phylogenetic relationships of bryophytes in the Karkaraly region and highlight its role as a refugium for both xerophytic and mesophilous taxa within a semi-arid landscape.

Isolation of Bacillus spp. Strains from soil biocenoses and their screening for phytase activity

2026-05-21T09:03:29+05:00

Phosphorus is a component of phosphates, nucleic acids, necessary for the synthesis of proteins, phospholipids, metabolic enzymes, and intracellular buffers. Therefore, all feeds must contain phosphorus in digestible form. In plant-based feeds, about 60-90% of phosphorus is found in the form of phytinic acid and its salts - phytates, which have anti-nutritive properties, which affects the maintenance of animals with a simple stomach: poultry, pigs, fish. Phytate, which is a phosphorus-containing waste from poultry farms, pig farms, and pond farms, negatively impacts the environmental situation. Fitases, which are myo-inositol phosphohydrolases, catalyze the hydrolysis of phytin acid to monophosphate and intermediate myo-inositol phosphate, which allows for the simultaneous solution of three problems: eliminating the need for feed phosphorus, reducing the anti-nutritional value of feed, and improving the ecological situation near poultry farms, farms, and pond facilities. From soil samples collected from the territories of the Akmola, Turkestan, Kyzylorda, and Zhambyl regions, 10 isolates of microorganisms belonging to the species Cytobacter oceaanisediminis, Peribacillus simplex, Bacillus mojavensis, Bacillus cereus, Bacillus pumilus, Bacillus thuringiensis, Bacillus megaterium, Bacillus subtilis, Bacillus paralicheniformis were isolated. Screening showed that 9 of these strains are capable of hydrolyzing phytinic acid, indicating their phytase activity. Of these, Bacillus mojavensis SH1 and Bacillus megaterium 1POL strains were selected as the most active strains for research. The study of biochemical properties showed that the phytase from B. mojavensis SH1 is active in the temperature range of 30-37°C and pH 8.0, while the phytase from B. megaterium 1POL is active at 60°C and pH 4.0-7.0. Phytase activity was 0.34 U/ml for the B. mojavensis SH1 and B. megaterium 1POL strains. The obtained results indicate the prospects of using B. mojavensis SH1 and B. megaterium 1POL strains as bacterial phytase producers.

Influence of Treg-cell subpopulations on HLA-E expression by chronic myeloid leukemia and Burkitt's B-cell lymphoma cells

2026-05-22T11:01:39+05:00

Modern research in the field of cancer immunology traditionally identifies T regulatory (Treg) cells as key suppressors of the antitumor immune response due to their direct inhibitory effects on effector populations, such as natural killer (NK) cells and cytotoxic T lymphocytes. However, the direct influence of Treg cells on the biological and immunosuppressive properties of the tumor cells themselves remains insufficiently understood. Hematologic malignancies, including chronic myeloid leukemia and Burkitt’s lymphoma, are hematopoietic neoplasms associated with a highly unfavorable prognosis during progression, largely driven by the tumor's ability to establish an immune-privileged microenvironment. In this study, we investigated the effect of natural (nTreg) and induced (iTreg) regulatory T cells on the expression of immunosuppressive molecules by chronic myeloid leukemia (K562) and Burkitt's B-cell lymphoma (Raji) cell lines in vitro. K562 and Raji cells were cultured either in direct contact with Treg cell subpopulations or in their culture supernatants, followed by flow cytometric analysis of immunosuppressive marker expression. We demonstrated that direct cell-to-cell contact with both nTreg and iTreg cells leads to a statistically significant upregulation of HLA-E expression on the surface of both investigated cell lines. These findings indicate that regulatory T cells are capable of modifying the tumor immunophenotype, thereby enhancing the capacity for immune evasion. Consequently, the results of this study expand current understanding of the role of Treg cells in the progression of hematologic malignancies and emphasize the necessity of considering their direct impact on tumor cells when developing novel immunotherapeutic strategies.

BIOTECHNOLOGICAL APPROACHES TO PRODUCING OF A COMBINED FERMENTED MILK DRINK

2026-04-14T09:46:33+05:00

The article presents the results of research on the development of a fermented milk product with vegetable filler based on goat milk. The research was conducted at the Department of Food Biotechnology of Almaty Technological University, as well as in the laboratory of biotechnology of specialised products and biologically active additives of the Kazakh Academy of Nutrition. In the preparation of fermented milk products, a starter culture consisting of pure cultures of Lactobacillus bulgaricus B6, Streptococcus thermophilus TA 45 and Lactobacillus acidophilus in a ratio of 1:5:1 was used. The starter culture was added with the mixer running, and stirring was carried out for 15 minutes. The milk was fermented until a milk-protein clot was formed with an acidity of (78±2)°T, pH=(4.70±0.02), and the fermentation time was 5 to 6 hours. The resulting clot was cooled to a temperature of 20-25 °C for 30 minutes, then stirred for 3-5 minutes. The starter culture used in the work consists of probiotics, which helps to extend the shelf life and prevents yeast and mould from growing in the final product. Lactobacillus bulgaricus synthesises a specific enzyme, peptidoglycan hydrolase, which is responsible for the hydrolysis of peptidoglycan. Streptococcus thermophilus has a high degree of viscosity, which contributes to the formation of a good clot and consistency. Acidophilic bacillus restores healthy intestinal microflora by suppressing the growth of harmful bacteria through the release of antibiotics. The addition of pumpkin to fermented milk products will help improve overall health and immunity, as well as normalise bowel function. The biologically active substances in pumpkin can improve the growth and development of lactic acid microorganisms in combined dairy products. The addition of vegetable filler not only does not impair the microscopic appearance of the product, but also improves its consistency.

Functional analysis of amino acid residues Y61, F72 and H180 in uracil-DNA glycosylase from Staphylococcus aureus

2026-04-27T13:15:19+05:00

In this study, bioinformatic and in silico structural analysis of uracil-DNA glycosylase from Staphylococcus aureus (SaUDG) was performed, leading to identification the amino acid residues Y61, F72 and H180 as potentially important for the catalytic activity of the enzyme. Based on the obtained data, SaUDG Y61S, F72N and H180Q mutant variants were constructed. The results of the enzymatic analysis revealed the absence of detectable catalytic activity in SaUDG F72N and H180Q mutants, whereas the Y61S substitution led to a significant reduction in activity.

These data indicate the key role of the F72 and H180 amino acid residues in the catalytic mechanism of SaUDG and highlight the functional importance of the Y61 residue for maintaining enzymatic activity. Overall, these results provide further insight into the structure and mechanism of action of SaUDG and are consistent with previous data on the conserved organization of the active site in first-family UDG enzymes.

ASSESSMENT OF GENETIC DIVERSITY AND POPULATION STRUCTURE OF IRIS KOLPAKOWSKIANA REGEL FROM KAZAKHSTAN USING MICROSATELLITE MARKERS

2026-07-03T18:27:19+05:00

Iris kolpakowskiana Regel is a rare wild iris species distributed in southeastern and southern Kazakhstan. To assess its genetic diversity and population structure, 168 individuals from 9 natural populations in the Almaty, Zhambyl, and Turkestan regions were analyzed using expressed sequence tag – simple sequence repeat (EST-SSR) markers. Of the nine primer pairs tested, 6 polymorphic loci were selected for further analysis. The mean number of alleles per locus was 3.1, with an average effective number of alleles of 2.4. Polymorphic information content (PIC = 0.688) indicated moderately high genetic variation and high marker informativeness. The highest genetic diversity was observed in populations from the Zhambyl region. AMOVA revealed that 55% of genetic variation occurred within populations and 45% among populations. High genetic differentiation was detected (F_ST = 0.481, p < 0.001), accompanied by limited gene flow (N_m= 0.654). Principal Coordinate Analysis, Neighbor-Joining clustering, and STRUCTURE analysis consistently identified two major genetic groups corresponding to southeastern Kazakhstan (Almaty region) and southern Kazakhstan (Zhambyl and Turkestan regions). The Mantel test showed no significant correlation between genetic and geographic distances (R² = 0.0008, p > 0.05). These results revealed geographic structuring and restricted genetic exchange among populations, providing the first genetic assessment of Iris kolpakowskiana and valuable information for its further conservation and management.