Biology subjects

Prazdnova, E.

Publications and source records attributed to Prazdnova, E..

5 recordsLinked to original sources

bioRxiv2025

Systemic induced plant resistance genes expression in winter wheat under treatment with antagonistic bacteria of Fusarium sp.

IntroductionFusarium species are devastating wheat pathogens. Plant growth-promoting rhizobacteria (PGPR) offer an effective biocontrol alternative. This study investigated the capacity of a Bacillus and Paenibacillus consortium to induce systemic resistance in winter wheat. MethodsWinter wheat plants were treated with a ten-strain PGPR consortium, with or without Fusarium oxysporum and F. graminearum. Expression of five PR-gene families was quantified in roots and shoots at 7 and 14 days post-treatment via RT-qPCR. Morphometric parameters were tracked for 28 days. ResultsThe consortium elicited a potent defense response. In roots at 7 days, PR-1 and PR-6 expression surged 16-fold and 38-fold, respectively. Defense activation in shoots was delayed, peaking at 14 days. After 28 days, PGPR-treated plants exhibited an 8% increase in shoot length. DiscussionThe results confirm that the bacterial strains effectively prime the wheat immune system, modulating early defense pathways and enhancing plant growth.

molecular biology↗

bioRxiv2024

Gellan gum-based nutrient medium increases the diversity of cultivated groups of soil microorganisms

Soil microbial communities contain a huge proportion of microorganisms that cannot be cultured on standard microbiological media and are available for study only by molecular methods such as metagenomics. Among them may be found microorganisms-producers of biologically active substances useful for medicine, biotechnology and agricultural activities of humans. Development of approaches for cultivation of such groups may open the way to the creation of fundamentally new antibiotic, antitumor drugs, phyto- and immunostimulants. We have proposed a solid oligotrophic medium for cultivation of soil microorganisms containing gellan gum, which allows to obtain cultures of more rare microorganisms compared to known media. Representatives of phylum Chloroflexota, Deinococcota, Planctomycetota, Actinomycetota, which were absent on agar media, were found in the metagenome of the community grown on this medium

microbiology↗

bioRxiv2023

SOLUBILIZER OF BACTERIAL ORIGIN SURFACTIN INCREASES THE BIOLOGICAL ACTIVITY OF C60 FULLERENE

Currently, there exists conflicting data regarding the biological activity of unmodified fullerene C60. Various sources report its toxicity, geroprotective activity, and potential interaction with DNA. Contradictory findings regarding the toxicity of C60 may arise from the use of toxic solvents, as well as the influence of bioavailability and bioactivity on the preparation conditions of C60 suspensions. Furthermore, the microbiota of experimental animals can impact geroprotective activity results by releasing surfactants that facilitate substance penetration through the cell membrane. In this study, we selected conditions for solubilizing fullerene C60 in a solution of surfactin, a surfactant of bacterial origin, as well as in a 2% aqueous solution of TWEEN 80, employing ultrasound. Through bioluminescent analysis using lux biosensors in E. coli MG1655, we observed that C60 in surfactin reduced induced genotoxic and oxidative stress. Given that surfactin enhances membrane permeability to fullerene C60, suspensions of fullerene in designated concentrations of surfactin can be regarded as a DNA protector and antioxidant, warranting further investigation as a promising component of novel drugs.

genetics↗

bioRxiv2023

NRPS genes provide antifungal activity to new Bacillus and Paenibacillus strains and change their expression in the presence of phytopathogens in a strain-specific manner

Fusarium diseases pose a significant threat to agricultural crops. In agricultural practice, various chemical fungicides, typically triazole-based, are often used to control fusariosis. However, this practice contributes to the development of resistant strains among the pathogenic fungi. A potential alternative to chemical fungicide treatments involves utilizing biopreparations derived from natural antagonists of Fusarium. Bacillus and Paenibacillus bacteria, isolated from farmland soils have shown notable antagonistic activity against phytopathogenic Fusarium fungi. Genetic analysis via PCR has indicated the presence of nonribosomal peptide synthase genes in the isolated bacterial strains, with the absence of chitinase activity suggesting that the antifungal effect primarily stems from nonribosomal synthesized peptides. Furthermore, the expression of these genes is heightened in the presence of fungi during co-culturing, although the magnitude of this effect appears to be specific to each strain and dependent on the pathogen in question. Field trials have demonstrated the efficacy of a biocontrol preparation made from studied Bacillus and Paenibacillus strains. These results suggest promising prospects for the development of pathogen-targeted treatments.

genetics↗

bioRxiv2023

Probiotic bacteria Lacticaseibacillus rhamnosus L108 and Lacticaseibacillus delbrueckii R2 increase lifespan and influence the expression of Caenorhabditis elegans longevity genes

AnnotationNumerous studies have shown that probiotics hold great promise in slowing down the aging process and extending life expectancy. Bacteria of the genus Lacticaseibacillus have been found to possess antioxidant, antimutagenic and anti-inflammatory effects, as well as the ability to regulate the expression of genes that control signaling defense mechanisms in model objects. In this study, we used the nematode Caenorhabditis elegans as a model organism to investigate the impact of Lacticaseibacillus rhamnosus L108(L.rhamnosus L108) and Lacticaseibacillus delbrueckii R2 on nematode lifespan and the expression levels of genes associated with healthy aging. Our results demonstrate that the Lacticaseibacillus rhamnosus L108 strain exhibits antioxidant properties and increases the average lifespan of nematodes by 15%. Lacticaseibacillus delbrueckii R2 also has a positive effect, extending the lifespan of the worms by 21.4%. Furthermore, analysis of longevity gene expression reveals a correlation between increased lifespan and activation of the insulin/insulin-like factor-1 pathway. Moreover, we observed a significant increase in the expression of the skn-1 gene, which encodes antioxidant proteins and enhances the antioxidant response. Our findings suggest that the expression of the skn-1 gene and the transcription factor SKN-1 are associated with activation of the p38 MAPK signaling pathway. Therefore, it seems that probiotic bacteria Lacticaseibacillus rhamnosus L108 and Lactobacillus delbrueckii R2 have a positive effect on lifespan due to increased expression of genes that underlie the regulation of conserved signaling pathways related to host defense.

molecular biology↗