Development of Resistance to Clarithromycin and Amoxicillin-Clavulanic Acid in Lactiplantibacillus plantarum In Vitro Is Followed by Genomic Rearrangements and Evolution of Virulence.

Ensuring the safety of the use of probiotics is a top priority. Obviously, in addition to studying the beneficial properties of lactic acid bacteria, considerable attention should be directed to assessing the virulence of microorganisms as well as investigating the possibility of its evolution under conditions of selective pressure. To assess the virulence of probiotics, it is now recommended to analyze the genomes of bacteria in relation to the profiles of the virulome, resistome, and mobilome as well as the analysis of phenotypic resistance and virulence in vitro. However, the corresponding procedure has not yet been standardized, and virulence analysis of strains in vivo using model organisms has not been performed. Our study is devoted to testing the assumption that the development of antibiotic resistance in probiotic bacteria under conditions of selective pressure of antimicrobial drugs may be accompanied by the evolution of virulence. In this regard, special attention is required for the widespread in nature commensals and probiotic bacteria actively used in pharmacology and the food industry. As a result of step-by-step selection from the Lactiplantibacillus plantarum 8p-a3 strain isolated from the "Lactobacterin" probiotic (Biomed, Russia), the L. plantarum 8p-a3-Clr-Amx strain was obtained, showing increased resistance simultaneously to amoxicillin-clavulanic acid and clarithromycin (antibiotics, the combined use of which is widely used for Helicobacter pylori eradication) compared to the parent strain (MIC8p-a3-Clr-Amx of 20 µg/mL and 10 µg/mL, and MIC8p-a3 of 0.5 µg/mL and 0.05 µg/mL, respectively). The results of a comparative analysis of antibiotic-resistant and parental strains indicate that the development of resistance to the corresponding antimicrobial drugs in L. plantarum in vitro is accompanied by the following: (i) significant changes in the genomic profile (point mutations as well as deletions, insertions, duplications, and displacement of DNA sequences) associated in part with the resistome and mobilome; (ii) changes in phenotypic sensitivity to a number of antimicrobial drugs; and (iii) an increase in the level of virulence against Drosophila melanogaster, a model organism for which L. plantarum is considered to be a symbiont. The data obtained by us indicate that the mechanisms of adaptation to antimicrobial drugs in L. plantarum are not limited to those described earlier and determine the need for comprehensive studies of antibiotic resistance scenarios as well as the trajectories of virulence evolution in probiotic bacteria in vivo and in vitro to develop a standardized system for detecting virulent strains of the corresponding microorganisms. IMPORTANCE Ensuring the safety of the use of probiotics is a top priority. We found that increased resistance to popular antimicrobial drugs in Lactiplantibacillus plantarum is accompanied by significant changes in the genomic profile and phenotypic sensitivity to a number of antimicrobial drugs as well as in the level of virulence of this bacterium against Drosophila. The data obtained in our work indicate that the mechanisms of antibiotic resistance in this bacterium are not limited to those described earlier and determine the need for comprehensive studies of the potential for the evolution of virulence in lactic acid bacteria in vivo and in vitro and to develop a reliable control system to detect virulent strains among probiotics.

Oral medical dissolution of gallstones in patients with gallstone disease

Being the main treatment for cholelithiasis, laparoscopic cholecystectomy does not always solve the problem. It often entails postcholecystectomy syndrome (PCS). Oral medication to dissolve gallstones with bile acids is alternative therapy for some patients. However, lack of efficacy and limited medical indications make it necessary to apply combination treatment tactics. This study was conducted to investigate the dissolution of gallstones during the combined effects of ursodeoxycholic acid (UDCA) and rosuvastatin as well as to assess the results of eradication therapy in the presence of H. pylory as a measure to prevent cholelithiasis in the course of treatment.

Mycoplasmas and Novel HO-1 Inducers: Recent Advances.

Inflammation and the ways for its regulation: The development of an effective system for the treatment of inflammatory diseases requires comprehensive studies of the cellular signaling molecular networks comprising responses to various stressors, including pathogenic and non-pathogenic microorganisms. Significant attention on fundamental and applied research has recently focused on inducers of hemе oxygenase-1 (HO-1) and inhibitors of the expression of this enzyme, which regulates expression of this and other cytoprotective molecules and modulation of inflammation. Recent studies indicate that mycoplasmas (a major group of human pathogens of the Mollicutes) are capable of modulating inflammatory responses through the activation of the Nrf2 and the expression of HO-1. In vitro experiments demonstrate that the membrane lipoproteins (LAMPs), along with lipoprotein derivatives (lipopeptide MALP-2) in mycoplasmas cause a "cross-talk" between the pro- and antiinflammatory signaling pathways. Importantly, lipopeptide/lipoprotein - induced expression of HO-1 tends to suppress inflammation. Conclusion: The study of the molecular network that causes the corresponding outcome can facilitate the development of new approaches for the treatment of inflammatory processes. The derivatives of LAMPs and MALP-2 and of their analogues may prove promising for the treatment of diseases associated with chronic inflammation.

Efficient fructose production from plant extracts by immobilized inulinases from Kluyveromyces marxianus and Helianthus tuberosus.

The enzymatic hydrolysis of poly- and oligosaccharides from plants seems like an advantageous approach for sugars production. Two inulinases producing fructose from plant oligosaccharides were isolated from yeast Kluyveromyces marxianus and plant Helianthus tuberosus. Both enzymes were immobilized on polymeric carriers by using the static adsorption approach. We could save 80.4% of the initial catalytic activity of plant inulinase immobilized on KU-2 cation-exchange resin and 75.5% of yeast enzyme activity adsorbed on AV-17-2P anion-exchange resin. After immobilization, the Km values increased 1.5 and 6 times for enzymes from K. marxianus and H. tuberosus, respectively. The optimal temperatures for catalysis of both enzymes were increased from 48-50 °C up to 70 °C. The activities of both immobilized enzymes remained unchanged after the 10 cycles of 20-min hydrolysis reaction at 70 °C model batch reactor. Sorbents, native and immobilized enzymes did not exhibit any mutagenic or cytotoxic activity.

[Effect of red and infrared radiation on the growth of Escherichia coli cells and production of recombinant barstar protein]. / Vliianie krasnogo i infrakrasnogo izlucheniia na rost kletok Escherichia coli i produktsiiu rekombinantnogo belka barstara.

Incoherent red and infrared low-intensity light enhanced the growth of the auxotrophic strain Escherichia coli AD494(DE3)pLysS and the production of the recombinant polypeptide barstar. Illumination also stimulated the growth of nonrecombinant E. coli cells.