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Phytohormones play a crucial role in regulating growth, productivity, and development while also aiding in the response to diverse environmental changes, encompassing both biotic and abiotic factors. Phytohormone levels in soil and plant tissues are influenced by specific soil bacteria, leading to direct effects on plant growth, development, and stress tolerance. Specific plant growth-promoting bacteria can either synthesize or degrade specific plant phytohormones. Moreover, a wide range of volatile organic compounds synthesized by plant growth-promoting bacteria have been found to influence the expression of phytohormones. Bacteria–plant interactions become more significant under conditions of abiotic stress such as saline soils, drought, and heavy metal pollution. Phytohormones function in a synergistic or antagonistic manner rather than in isolation. The study of plant growth-promoting bacteria involves a range of approaches, such as identifying singular substances or hormones, comparing mutant and non-mutant bacterial strains, screening for individual gene presence, and utilizing omics approaches for analysis. Each approach uncovers the concealed aspects concerning the effects of plant growth-promoting bacteria on plants. Publications that prioritize the comprehensive examination of the private aspects of PGPB and cultivated plant interactions are of utmost significance and crucial for advancing the practical application of microbial biofertilizers. This review explores the potential of PGPB–plant interactions in promoting sustainable agriculture. We summarize the interactions, focusing on the mechanisms through which plant growth-promoting bacteria have a beneficial effect on plant growth and development via phytohormones, with particular emphasis on detecting the synthesis of phytohormones by plant growth-promoting bacteria. [ABSTRACT FROM AUTHOR]

Objective: Milk composition varies considerably and depends on paratypical, genetic, and epigenetic factors. MiRNAs belong to the class of small non-coding RNAs; they are one of the key tools of epigenetic control because of their ability to regulate gene expression at the post-transcriptional level. We compared the relative expression levels of miR-106b, miR-191, and miR-30d in milk to demonstrate the relationship between the content of these miRNAs with protein and fat components of milk in Holstein and Ayrshire cattle. Methods: Milk fat, protein, and casein contents were determined in the obtained samples, as well as the content of the main fatty acids (g/100 g milk), including: saturated acids, such as myristic (C14:0), palmitic (C16:0), and stearic (C18:0) acids; monounsaturated acids, including oleic (C18:1) acid; as well as long-, medium- and short-chain, polyunsaturated, and trans fatty acids. Real-time stem-loop one-tube reverse transcription polymerase chain reaction with TaqMan probes was used to measure the miRNA expression levels. Results: The miRNA expression levels in milk samples were found to be decreased in the first two months in Holstein breed, and in the first four months in Ayrshire breed. Correlation analysis did not reveal any dependence between changes in the expression level of miRNA and milk fat content, but showed a multidirectional relationship with individual milk fatty acids. Positive associations between the expression levels of miR-106b and miR-30d and protein and casein content were found in the Ayrshire breed. Receiver operating characteristic curve analysis showed that miR-106b and miR-30d expression levels can cause changes in fatty acid and protein composition of milk in Ayrshire cows, whereas miR-106b expression level determines the fatty acid composition in Holsteins. Conclusion: The data obtained in this study showed that miR-106b, miR-191, and miR-30d expression levels in milk samples have peculiarities associated with breed affiliation and the lactation period. [ABSTRACT FROM AUTHOR]

Antibodies are protein molecules whose primary function is to recognize antigens. However, recent studies have demonstrated their ability to hydrolyze specific substrates, such as proteins, oligopeptides, and nucleic acids. In 2023, two separate teams of researchers demonstrated the proteolytic activity of natural plasma antibodies from COVID-19 convalescents. These antibodies were found to hydrolyze the S-protein and corresponding oligopeptides. Our study shows that for antibodies with affinity to recombinant structural proteins of the SARS-CoV-2: S-protein, its fragment RBD and N-protein can only hydrolyze the corresponding protein substrates and are not cross-reactive. By using strict criteria, we have confirmed that this proteolytic activity is an intrinsic property of antibodies and is not caused by impurities co-eluting with them. This discovery suggests that natural proteolytic antibodies that hydrolyze proteins of the SARS-CoV-2 virus may have a positive impact on disease pathogenesis. It is also possible for these antibodies to work in combination with other antibodies that bind specific epitopes to enhance the process of virus neutralization. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID-19), caused by the SARS-CoV-2 coronavirus, leads to various manifestations of the post-COVID syndrome, including diabetes, heart and kidney disease, thrombosis, neurological and autoimmune diseases and, therefore, remains, so far, a significant public health problem. In addition, SARS-CoV-2 infection can lead to the hyperproduction of reactive oxygen species (ROS), causing adverse effects on oxygen transfer efficiency, iron homeostasis, and erythrocytes deformation, contributing to thrombus formation. In this work, the relative catalase activity of the serum IgGs of patients recovered from COVID-19, healthy volunteers vaccinated with Sputnik V, vaccinated with Sputnik V after recovering from COVID-19, and conditionally healthy donors were analyzed for the first time. Previous reports show that along with canonical antioxidant enzymes, the antibodies of mammals with superoxide dismutase, peroxidase, and catalase activities are involved in controlling reactive oxygen species levels. We here show that the IgGs from patients who recovered from COVID-19 had the highest catalase activity, and this was statistically significantly higher each compared to the healthy donors (1.9-fold), healthy volunteers vaccinated with Sputnik V (1.4-fold), and patients vaccinated after recovering from COVID-19 (2.1-fold). These data indicate that COVID-19 infection may stimulate the production of antibodies that degrade hydrogen peroxide, which is harmful at elevated concentrations. [ABSTRACT FROM AUTHOR]

Exosomes are nanovesicles with a 40–150 nm diameter and are essential for communication between cells. Literature data suggest that exosomes obtained from different sources (cell cultures, blood plasma, urea, saliva, tears, spinal fluid, milk) using a series of centrifugations and ultracentrifugations contain hundreds and thousands of different protein and nucleic acid molecules. However, most of these proteins are not an intrinsic part of exosomes; instead, they co-isolate with exosomes. Using consecutive ultracentrifugation, gel filtration, and affinity chromatography on anti-CD9- and anti-CD63-Sepharoses, we isolated highly purified vesicle preparations from 18 horse milk samples. Gel filtration of the initial preparations allowed us to remove co-isolating proteins and their complexes and to obtain highly purified vesicles morphologically corresponding to exosomes. Using affinity chromatography on anti-CD9- and anti-CD63-Sepharoses, we obtained extra-purified CD9+ and CD63+ exosomes, which simultaneously contain these two tetraspanins, while the CD81 tetraspanin was presented in a minor quantity. SDS-PAGE and MALDI analysis detected several major proteins with molecular masses over 10 kDa: CD9, CD63, CD81, lactadherin, actin, butyrophilin, lactoferrin, and xanthine dehydrogenase. Analysis of extracts by trifluoroacetic acid revealed dozens of peptides with molecular masses in the range of 0.8 to 8.5 kDa. Data on the uneven distribution of tetraspanins on the surface of horse milk exosomes and the presence of peptides open new questions about the biogenesis of these extracellular vesicles. [ABSTRACT FROM AUTHOR]

Till yet there is no data concerning mechanisms of autoimmune diseases development. Experimental autoimmune encephalomyelitis (EAE) prone C57BL/6 (T- and B-lymphocyte response), non-autoimmune CBA, and Th mice with T cell response were immunized with myelin oligodendrocyte glycoprotein (MOG35-55) to compare di erent characteristics of autoimmune reaction development. Bone marrow di erentiation profiles of hematopoietic stem cells (HSCs), lymphocyte proliferation in various organs associated with the production of antibodies against DNA, myelin basic protein (MBP), and MOG, as well as abzymes hydrolyzing these antigens, were analyzed before and after immunization. Profiles of HSC di erentiation [BFU-E (erythroid burst-forming unit (early erythroid colonies), CFU-E (erythroid burst-forming unit (late erythroid colonies), CFU-GM (granulocytic-macrophagic colony-forming unit), and CFU-GEMM granulocytic-erythroid-megakaryocytic-macrophagic colony-forming unit] and patterns of lymphocyte proliferation in di erent organs (brain, spleen, thymus, and lymph nodes) were very di erent for C57BL/6, CBA, and Th mice. We conclude that only C57BL/6 mice were predisposed to spontaneous and MOG-induced acceleration of EAE development. CBA mice are not prone to the development of autoimmune reactions. After immunization, Th mice demonstrate changes in several parameters similar to C57BL/6 and other to CBA mice; Th mice are more prone to developing autoimmune reactions than CBA mice. Our data may be important for understanding the combined presence in mice lymphocytes with T and B cell responses for spontaneous and induced autoimmune diseases. [ABSTRACT FROM AUTHOR]

Cobalt is a transition metal and an essential trace element that is required for vitamin B12 biosynthesis, enzyme activation, and so on but is toxic in high concentrations. It was shown that the content of different elements in the plasma of 2-month-old BALB/c mice (control group) decreased in the following order: Ca > Mg > Si > Fe > Zn > Cu ≥ Al ≥ B. The treatment of mice with CoCl2 did not appreciably change the relative content of Ca, Cu, and Zn, but a significant increase in the content of B (2.3-fold), Mg (1.5-fold), Al and Fe (2.1-fold), and Si (3.4-fold) was found. The treatment of mice led to a 2.2-fold decrease in the concentration of the total blood protein and a 1.7 ± 0.2-fold decrease of total immunoglobulin Gs (IgGs). Deoxyribonuclease IgGs corresponding to mice treated (t-IgGs) and non-treated (nt-IgGs) with CoCl2 contained intrinsically bound metal ions; these IgGs hydrolyzed DNA with very low activity but were not active in the presence of ethylenediaminetetraacetic acid or after Ab dialysis against ethylenediaminetetraacetic acid. The average RAs of deoxyribonuclease nt-IgGs increased after addition of external metal ions in the following order: Zn2+ < Ca2+ < Cu2+ < Fe2+ < Mn2+ < Mg2+ < Co2+ < Ni2+. Interestingly, t-IgGs demonstrated lower activities than those for nt-IgGs either in the absence of external metal ions (2.7-fold) or in the presence of Cu2+ (9.5-fold) > Co2+ (5.6-fold) > Zn2+ (5.1-fold) > Mg2+ (4.1-fold) > Ca2+ (3.0-fold) > Fe2+ (1.3-fold). However, the RAs of t-IgGs were remarkably more active than nt-IgGs in the presence of best activators of t-IgGs Ni2+ (1.4-fold) and especially Mn2+ (2.2-fold). The data may be useful for an understanding of Co toxicity, its effect on the concentration of other metal ions, and a change of metal-dependent specificity of Abzs. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Human immunodeficiency virus (HIV) infection is associated with pronounced oxidative stress, leading to the development of various virus-associated pathologies. A wealth of evidence suggests that, along with canonical enzymes of reactive oxygen species regulation, human blood contains antibodies with peroxidase, superoxide dismutase, and catalase activities. Here we show that the catalase activity of IgGs and their κκ-IgG, λλ-IgG, and κλ-IgG subfractions of HIV-infected individuals is significantly different compared to the healthy donors., Methods: Protein G-Sepharose sorbent was used to resolve IgG from blood of healthy donors and HIV-infected patients by affinity chromatography. Subfractions of κκ-IgG, λλ-IgG, and κλ-IgG were separated from IgGs samples of each group by affinity chromatography on sorbents containing immobilized antibodies to κ or λ light human chains. The IgG catalase activity level was measured spectrophotometrically by evaluating the decrease in optical density (A240) due to hydrogen peroxide decomposition., Results: The relative catalase activity of antibodies from HIV-infected patients ( kcat = (1.41 ± 0.92) × 103 min-1, 95% CI: [1.01-1.81]) was statistically significant, 1.6 times higher ( p = 0.014) compared to apparently healthy donors ((0.86 ± 0.49) × 103, 95% CI: [0.69-1.03]). The activity level of κκ-IgG HIV-infected patients ((0.44 ± 0.04) × 103 min-1) was 1.4 times higher than that of λλ-IgGs ((0.31 ± 0.025) × 103 min-1); the opposite was observed for κκ-IgGs from apparently healthy donors, which activity ((0.17 ± 0.015) × 103 min-1) was 3.1 times lower compared to λλ-IgGs ((0.53 ± 0.045) × 103 min-1)., Conclusions: Thus, the data obtained may indicate that IgG with increased catalase activity may prevent harmful processes arising from oxidative stress in HIV-infected patients, acting as an additional natural molecular mechanism of regulation of hydrogen peroxide level., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Published by IMR Press.)

Cobalt is a transition metal and an essential trace element that is required for vitamin B₁₂ biosynthesis, enzyme activation, and so on but is toxic in high concentrations. It was shown that the content of different elements in the plasma of 2-month-old BALB/c mice (control group) decreased in the following order: Ca > Mg > Si > Fe > Zn > Cu ≥ Al ≥ B. The treatment of mice with CoCl₂ did not appreciably change the relative content of Ca, Cu, and Zn, but a significant increase in the content of B (2.3-fold), Mg (1.5-fold), Al and Fe (2.1-fold), and Si (3.4-fold) was found. The treatment of mice led to a 2.2-fold decrease in the concentration of the total blood protein and a 1.7 ± 0.2-fold decrease of total immunoglobulin Gs (IgGs). Deoxyribonuclease IgGs corresponding to mice treated (t-IgGs) and non-treated (nt-IgGs) with CoCl₂ contained intrinsically bound metal ions; these IgGs hydrolyzed DNA with very low activity but were not active in the presence of ethylenediaminetetraacetic acid or after Ab dialysis against ethylenediaminetetraacetic acid. The average RAs of deoxyribonuclease nt-IgGs increased after addition of external metal ions in the following order: Zn²⁺< Ca²⁺ < Cu²⁺ < Fe²⁺ < Mn²⁺ < Mg²⁺ < Co²⁺ < Ni²⁺. Interestingly, t-IgGs demonstrated lower activities than those for nt-IgGs either in the absence of external metal ions (2.7-fold) or in the presence of Cu²⁺ (9.5-fold) > Co²⁺ (5.6-fold) > Zn²⁺ (5.1-fold) > Mg²⁺ (4.1-fold) > Ca²⁺ (3.0-fold) > Fe²⁺ (1.3-fold). However, the RAs of t-IgGs were remarkably more active than nt-IgGs in the presence of best activators of t-IgGs Ni²⁺ (1.4-fold) and especially Mn²⁺ (2.2-fold). The data may be useful for an understanding of Co toxicity, its effect on the concentration of other metal ions, and a change of metal-dependent specificity of Abzs., (Copyright © 2012 John Wiley & Sons, Ltd.)