Vol 59, No 4 (2023)

With the growing number of cancers, new assistive tools are required to obtain extensive molecular profiles of patients to help identify the disease. Early diagnosis of cancer is based on the analysis of relevant biomarkers, which can be used to monitor the population in order to identify the disease until it can be determined using standard methods and is not clinically manifest. One of the potential markers of cancer is heat shock proteins that act as molecular chaperones. Changes in heat shock proteins expression can serve as an important diagnostic marker of the cell’s response to damage. The paper presents a brief overview of the prevalence of oncological diseases in the world, the need of early oncological diagnostics development, as well as the prospects for the use of heat shock proteins in making an oncological diagnosis.

Potentially corrosive active microorganisms isolated from structural materials with signs of biofouling on the coast of Kislaya Bay (Barents Sea, Russia) were studied: sulfate-reducing, iron-oxidizing and sulfur-oxidizing bacteria. Cultures of sulfate-reducing bacteria (Desulfovibrio sp., Halodesulfovibrio sp.), sulfur-oxidizing bacteria (Dietzia sp.), and iron-oxidizing bacteria (Pseudomonas fluorescens, Bacillus sp.) were identified on the basic of the determining the nucleotide sequences of the 16S rRNA gene. The methods of scanning electron microscopy, energy dispersive microanalysis of the chemical composition and X-ray phase analysis revealed significant changes in the structure and chemical composition of the surface layer of steel reinforcement samples exposed for 28 days in the presence of isolated microorganisms that demonstrated their active participation in corrosion processes. It has been shown that the formation of mineral analogues in corrosion products depends on the strains of studied bacteria and peculiarities of their metabolism. Sulfate-reducing bacteria isolated from the littoral zone of the Barents Sea showed the highest activity in the development of corrosion processes.

We have explored the effect of a new strain of the mushroom Inonotus obliquus (Ach.:Pers.) Pilat (Basidiomycota) F-1375 on melanin production in a glucose-tryptone medium, adding the preparation of betulin, chemically pure tyrosine, under electric lighting and under dark conditions. The betulin preparation in the examined concentrations had practically no effect on the production of melanin, while high concentrations of tyrosine stimulated the production of melanin both under illumination and in the dark. All studied samples of mushroom melanin are non-toxic: both isolated from natural (TC₅₀ = 96 ± 8 μg/mL) and cultured in a liquid medium with the addition of betulin and tyrosine (TC₅₀ from 164 to 400 μg/mL); active against HIV-1 in MT-4 cell culture (IC₅₀ 1 to 4.3 μg/mL, SI 17 to 192). The selectivity indices of the learned preparations of melanin of cultivated Inonotus obliquus F-1375 against the human immunodeficiency virus subtype A were at the level of 33-192, which makes it possible to recommend them for the development of antiviral agents. Melanin from mushroom Inonotus obliquus F-1375 cultured in the electrical light with the addition of 10 and 20 mM tyrosine has the highest selectivity index for retrovirus HIV-1 (SI 192).

Amplification of long fragments from complex templates, such as eukaryotic genomic DNA, is considered a difficult task for most DNA polymerases. In this research, 6 variants of DNA polymerases were used to amplify full-length sequences from the genomic DNA of Solanum tuberosum genes encoding translation initiation factors of the eIF4E family, as well as for the synthesis of fragments of the potato Y virus genome from cDNA of potato plants infected by this virus. It was found that the efficiency of amplification by various DNA polymerases generally decreased with increasing length of the amplicons. LongAmp and Platinum SuperFi II polymerases demonstrated the highest efficiency in the synthesis of long fragments, which made it possible to synthesize PCR products with a length of more than 10,000 base pairs with high efficiency. The lowest efficiency was demonstrated by Encyclo polymerase. None of the DNA polymerases provided efficient amplification of all the studied DNA fragments. At the same time, any of the studied DNA fragments could be effectively amplified using at least one DNA polymerase variant. Thus, the choice of DNA polymerase was of key importance for the efficiency of the synthesis of a desired PCR product.

Using a naïve human scFv phage library, affinity selection of miniantibodies specific to heat shock proteins isolated from MH22a hepatoma cells and Sp2/0-Ag14 plasmacytoma cells was carried out. Using the obtained phage antibodies by dot-immunoassay and enzyme-linked immunosorbent assay, the dynamics of the concentration of heat shock proteins in the blood serum of mice with implanted tumor cells of the MH22a line was studied. Starting from the 14th day after xenotransplantation, there was a gradual increase in the level of heat shock proteins in the blood serum. It was found that after implantation of tumor cells, tumor growth was accompanied by a significant increase in the accumulation of heat shock proteins in the blood serum. It has been shown that miniantibodies specific to heat shock proteins are an effective tool for determining and monitoring the accumulation of heat shock proteins in the blood serum of animals.