Applied Biochemistry and Microbiology最新文献

Cryopreservation results in a significant reduction in the fertilizing properties of sperm, but genetic variations among different animal species affect the survival of germ cells after cryopreservation. Searching for specific genetic markers can be an effective way to select bulls before semen collection for cryopreservation. A correlation analysis of the expression level of candidate genes, HSPA1A, HSBPA1, AFAF, AQP3, and AQP11, with sperm quality indicators in native and decryopreserved sperm of Holstein bulls was carried out. Highly reliable positive correlations of the studied gene transcripts with a number of indicators of sperm viability and negative ones with indicators characterizing the loss of their functionality were revealed. The results of this study can be used to develop transcriptional biomarkers of bull sperm quality, namely based on the parameters of cryoresistance and the fertilizing potential of sperm.

This work examines the mechanical properties of a transformable fibrous nitrocellulose matrix that can be used as a cell carrier in bioartificial cell systems. To measure the mechanical properties of fibrous matrices, a device was developed and constructed that can be used to conduct studies of a variety of matrices, which are the basis for populating cell cultures during the formation of artificial organs and tissues. The effect of reducing the mechanical stress and Young’s modulus of a wet nitrocellulose matrix compared to a dry one at the same relative deformation was discovered experimentally, which is due to the porosity of the matrix and fluid friction between the fibers. In the theoretical description of the mechanical properties, 2-, 3-, 5-, and 9-parametric Mooney–Rivlin hyperelastic models were used. Their parameters were calculated for both a dry and a wet nitrocellulose matrix based on the experimental data obtained, and a comparative analysis of the experimental data and theoretical dependences of mechanical stress and Young’s modulus were carried out. The results obtained can be used in the future for a detailed study of the cell-matrix interaction, which may make it possible to develop modern new generation biomaterials with physical properties close to living tissue for use in regenerative medicine.

The influence of mechanical and physical methods of cell disruption on the activity of beta-galactosidases produced by lactose-fermenting yeast and lactic acid bacteria after separate and co-cultivation in whey permeate was studied. It was found that ultrasound and heat treatment are the most effective methods that allow obtaining the enzyme with significantly higher activity than after quartz sand and glass bead mealing. The beta-galactosidases received as result of co-cultivation of some yeast strains and viscous strains of lactic acid bacteria had activity higher than beta-galactosidases from individual producers. The highest lactase activity (0.8–0.9 IU/ cm³) was obtained using heat treatment and the viscous strain of Lactobacillus acidophilus in combination with the yeasts Kluyveromyces marxianus Y-1338 and Kluyveromyces lactis Y-1333.

The proposed biotechnological approach is based on the use of aqueous dispersions or colloidal solutions of fullerene-containing compounds for seed material treatment, providing growth stimulation and helping to increase plant viability and productivity. The experiments showed the growth-stimulating effect on plants of winter wheat (Triticum aestivum L.) varieties “Zarya”, “Rubezhnaya”, and the trititrigia line (×Trititrigia) M116 of aqueous dispersions of C₆₀ fullerene and salts of amino acid derivatives of C₆₀ fullerene, used for presowing treatment (soaking) of seeds in a solution volume equivalent to their moisture capacity. Pre-sowing treatment (soaking) of winter wheat seeds of the “Rubezhnaya” variety in the presence of fullerene-containing aqueous dispersions in a field experiment demonstrated an increase in the yield and vitality of plants, and an increase in the weight and number of grains in an ear. The proposed biotechnological approach has prospects for effective use in agriculture for processing seed material, increasing plant viability and yield of important food crops.

The parameters of lyophilization of substances of organ-tissue and cultural origin containing a fixed rabies virus were determined. The objects of this research were the “Moscow 3253,” СVS, and “Saratov” strains of the rabies virus used in the production of commercial and experimental batches of rabies immunoglobulin from horse blood serum. For substances containing “Moscow 3253,” CVS, and “Saratov” strains, the effects of both freezing and eutectic temperatures were identical. The use of the developed lyophilization protocol allowed us to obtain samples as well-formed porous tablets. The infectivity of the freeze-dried Moscow 3253, CVS, and Saratov strains was 6.2, 7.1, and 6.8 logID₅₀/mL, respectively. Thus, the proposed freeze-drying regime is acceptable for obtaining samples of rabies virus strains used for the production of rabies immunoglobulin.

Genetic polymorphism of a collection of accessions of the genus Lupinus was studied using SSR marking technology. The average level of intraspecies DNA polymorphism for L. albus, L. angustifolius, and L. luteus was found to be 25.8, 21.6, and 34.7%, respectively. The informative markers for genotyping and identification of Russian lupine varieties and breeding samples were determined. As a result of assessment of the genetic distance, genetically divergent accessions were identified that can serve as promising material for use in breeding programs for white (L. albus) and yellow (L. luteus) lupine, namely, SN 8-12, SN 96-15 DT1, KCI-22 d-15, KCI 22 d-17, 19-PIO-18-3, and SN 12-11-02-2-4-1. Based on the data obtained, molecular formulas of the studied samples were developed and reference genetic passports were compiled for the lupine varieties Belorozovyi 144, Nadyezhnyi, Antei, and Kurshavel. The practical results of this research and new knowledge on the structure of the genomes of Russian lupine varieties can be used in variety testing, seed production, and as a system of information support for the processes of selection and preservation of the national gene pool of lupine, a valuable agricultural crop.

Qualitative and quantitative characteristics of the aqueous phase obtained as a result of hydrothermal liquefaction of biomass of excessive activated sludge from municipal and domestic sewage treatment plants in Kaliningrad have been investigated experimentally. The content of organic compounds averaged 11 592 ± 571 mg O/dm³, and the biochemical index was 0.57. Aromatic compounds, carboxylic acids, and heterocyclic nitrogen-containing compounds were found in the composition of the aqueous phase. From activated sludge of treatment facilities of PJSC Nizhnekamskneftekhim, Republic of Tatarstan, 11 isolates–destructors of components of the aqueous phase were isolated. Their cultural and morphological characteristics were evaluated, and the necessary dilution of the aqueous phase for their cultivation was determined. It was noted that, in the process of cultivation of isolates, S2, S7, and S11 are able to neutralize components of the aqueous phase effectively in comparison with other isolated cultures: the efficiency of degradation by COD was 69, 73, and 75%, respectively. Based on 16S rRNA gene sequencing, isolate S2 had the highest similarity to Pseudomonas glycinae MS586 (99.52%), S7 with Paenarthhobacter nicotinovorans DSM 420 (99.8%), and isolate S11 with Comamonas testosteroni KS 0043 (99.6%). The most active isolates can be used for the treatment of highly concentrated wastewater before preliminary discharge into the sewerage network and natural water bodies.

The yeast microflora of brined Ossetia cheeses made from raw milk by small farms in various regions of North and South Ossetia has been studied for the first time. A total of 17 yeast species belonging to ten genera were identified. It is shown that the composition of the yeast microflora of Ossetia cheeses depends on the place of production, the microflora of the raw milk and starter culture, and the type of milk. Most of the Ossetian cheeses studied were dominated by lactose-utilizing yeasts Kluyveromyces lactis and Debaryomyces hansenii, as well as by lactose-negative yeasts Saccharomyces cerevisiae, Pichia kudriavzevii, and P. fermentans. The composition of the microflora of artisanal Ossetia cheeses is more diverse than that of commercial cheeses produced from pasteurized milk.

Traditional two-dimensional (2D) cell cultures have limited capabilities for modeling complex interactions between viruses and host cells, which reduces the efficiency of the studies when trying to transfer data obtained to in vivo models. Three-dimensional (3D) cell cultures are the most physiologically relevant models, without the limitations inherent to 2D cultures. The use of 3D models opens up new possibilities when studying viral infections and developing new antiviral drugs and preventive measures. We constructed a biological model based on 3D spheroids from the human embryonic lung cell line (HELC-3) and tested it on the example of the analysis of replicative activity of herpes simplex virus type 1, strain L₂ (HSV-1/L₂). The spheroids were obtained when cultivating the cells in hydrogel microwells. The replicative activity of HSV-1 in 3D culture of HELC-3 cells was estimated by a cytopathic effect of the culture liquid of virus-infected spheroids on a monolayer culture of the same cells (2D format). It was demonstrated that HSV-1 replicates efficiently in spheroids. Thus, the model based on 3D spheroids from HELC-3 cells can be considered as a promising tool for studying the HSV-1 replication cycle in vitro, molecular mechanisms of its pathogenesis and persistence, as well as the analysis of potential antiviral drugs and vaccines.

The aim of this study was to create biodegradable scaffolds based on natural silk fabrics for regenerative medicine. Fabrics with different densities gas-chiffon (15 g/m²) and double-sided satin (155 g/m²) were used as matrices. The samples were preliminarily treated with a water–alcohol solution of calcium chloride for different periods of time to obtain the samples with different degrees of degradation. Morphological studies using light microscopy confirmed structural changes in the tissues after this treatment. Degradation of the obtained scaffolds was studied in vitro using Fenton’s reagent with different duration of incubation (15, 30, and 45 days). The rate of scaffold destruction depended on the type of fabric and time of preliminarily treatment with calcium chloride. The highest degradation rate was observed for gas-chiffon, while satin demonstrated slower destruction. The results obtained can be used when optimizing the properties of silk fabrics for their use in regenerative medicine and development of efficient methods to control their biodegradation.