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BackgroundIt is known that the gut microbiome of a healthy person affects the process of COVID-19 after getting infected with SARS-CoV-2 virus. It is also believed that colchicine can alleviate the severity of COVID-19.ObjectiveCurrent investigations aimed to evaluate the associations between the baseline gut microbiota composition of healthy and Familial Mediterranean fever (FMF) - carrier Armenian men populations, and the severity of the COVID-19 disease after their infection with the SARS-CoV-2. The study has a purpose of answering three core questions: i. Do the characteristics of gut microbiome of Armenians affect the course of COVID-19 severity? ii. How does the COVID-19 disease course on go for FMF patients who have been taking colchicine as a medication over the years after getting infected with SARS-CoV-2? iii. Is there an initial gut micribiota structure pattern for non-FMF and FMF patients in the cases when COVID-19 appears in mild form?MethodsThe gut microbiota composition in non-FMF and FMF patients before the first infection (mild and moderate course of COVID-19) was considered. COVID-19 was diagnosed by SARS-CoV-2 nucleic acid RT-PCR in nasopharyngeal swab and/or sputum.ResultsThe number of patients with male FMF with mild COVID-19 was approximately two times higher than that of non-FMF male subjects with COVID-19. In addition, an association of COVID-19 disease severity with the baseline gut Prevotella, Clostridium hiranonis, Eubacterium biforme, Veillonellaceae, Coprococcus, and Blautia diversities in the non-FMF and FMF populations were revealed by us, which can be used as risk/prognostic factor for the severity of COVID-19.

Antibiotic resistance and infection recurrence are critical issues in treating bacterial vaginosis, the most common vaginal disorder in women of reproductive age. Novel alternatives to traditional antibiotics, such as peptidomimetics, have the potential to address this challenge. Previously, two series of cationic amphiphiles (CAms) were developed with both hydrophilic head groups and non-polar domains, giving them the ability to self-assemble into supramolecular nanostructures with membrane-lytic properties. Those CAms were shown to be effective against biofilms of Gardnerella vaginalis while preserving the commensal microbiota. Two new series of CAms were designed with varying levels of flexibility between the hydrophilic head groups and the hydrophobic domains. Activities against the vaginal pathogen G. vaginalis ranged from 1.3 to 18.5 µM, while the tested vaginal lactobacilli were significantly more tolerant of CAms, with minimal inhibitory concentration values as high as 208 µM. Minimal biofilm bactericidal concentrations of the tested CAms ranged from 21.47 to

Small-molecule cationic amphiphiles (CAms) were designed to combat the rapid rise in drug-resistant bacteria. CAms were designed to target and compromise the structural integrity of bacteria membranes, leading to cell rupture and death. Discrete structural features of CAms were varied, and structure-activity relationship studies were performed to guide the rational design of potent antimicrobials with desirable selectivity and cytocompatibility profiles. In particular, the effects of cationic conformational flexibility, hydrophobic domain flexibility, and hydrophobic domain architecture were evaluated. Their influence on antimicrobial efficacy in Gram-positive and Gram-negative bacteria was determined, and their safety profiles were established by assessing their impact on mammalian cells. All CAms have a potent activity against bacteria, and hydrophobic domain rigidity and branched architecture contribute to specificity. The insights gained from this project will aid in the optimization of CAm structures.

The stability of RNA is a critical factor in determining its functionality and degradation in the cell. In recent years, it has been shown that the stability of RNA depends on a complex interaction of external and internal factors. External conditions, such as temperature fluctuations, the level of acidity of the environment, the presence of various substances and ions, as well as the effects of oxidative stress, can change the structure of RNA and affect its stability. Internal factors, including the specific structural features of RNA and its interactions with protein molecules, also have a significant impact on the regulation of the stability of these molecules. In this article, we review the main factors influencing RNA stability, since understanding the factors influencing this extremely complex process is important not only for understanding the regulation of expression at the RNA level but also for developing new methods for isolating and stabilizing RNA in preparation for creating biobanks of genetic material. We reviewed a modern solution to this problem and formulated basic recommendations for RNA storage aimed at minimizing degradation and damage to the molecule. [ABSTRACT FROM AUTHOR]

The potential probiotic properties of three Bacillus strains were studied. A probiotic supplement for the African catfish Clarias gariepinus was produced via the solid-state fermentation protocol and incorporated into the fish feed for a period of seven weeks. Since the 36th day of the experiment, all experimental groups had a statistically significant increase in their weight gain than the control group. The maximum weight gain observed in fish fed the probiotic-supplemented feed was 29.16% higher than that of the control group, and the maximum feed conversion rate improvement was 24%. Cell-free extracts from these strains showed antioxidant (11.55–27.40%) and DNA-protective (45.33–61.83%) activity in a series of in vitro biosensor tests. Further investigation into the antimutagenic activity of the strains revealed that two of them reduced the level of induced mutagenesis in an Escherichia coli model (by 33.58% and 54.35%, respectively). We also assessed the impact of probiotic strains on the expression of several key genes in the host (C. gariepinus), including hsp70, cxc, tnfα, il1β, and lysC. More than a 10-fold increase in expression rates was observed for hsp70 in gonads and liver; for cxc in muscles and gonads; for tnfα in brain, gills, and liver; for il1β in the brain, gills, gonads, and liver; and for lysC in gills, gonads, liver, and muscles. This study provides evidence that probiotics exhibiting antioxidant and antimutagenic properties can provide significant benefits in vivo within aquaculture systems. The molecular effects of these probiotics appear to be complex and tissue-specific, with both upregulation and downregulation of immune system genes observed. Nevertheless, at the organismal level, the impact was unequivocally positive in terms of aquaculture objectives, manifested as enhanced body weight gain in the fish. Consequently, these Bacillus strains warrant serious consideration as potential probiotics for this species. [ABSTRACT FROM AUTHOR]

The article is a brief literature review. This article provides an overview of the Quorum Sensing system in bacterial communities, highlighting the peculiarities of the system for gram-positive and gramnegative microorganisms. Basic information about the three existing Quorum Sensing systems is presented. Information is also given about different types of autoinducers, which are signaling molecules that trigger a cascade of behavioral reactions. The importance of the Quorum Sensing system as one of the fundamental mechanisms in the formation and regulation of bacterial biofilms is described, emphasizing the significance of biofilm microorganisms for modern clinical medicine and their impact on aggravating the issue of antibiotic resistance. The main mechanisms of inhibiting bacterial quorum, including by other microorganisms, are presented. The work discusses enzymatic and non-enzymatic methods of inhibiting the Quorum Sensing system, points of application and mechanisms of action. Some microorganisms with confirmed enzymatic activity by Quorum Quenching are indicated. Also presented are registered cases of suppression of other bacteria by microorganisms through the Quorum Sensing inhibitors system.

Intestinal microorganisms play a crucial role in health and disease. The disruption of host-microbiota homeostasis has been reported to occur not only during disease development but also as a result of medication. Familial Mediterranean fever (FMF) is an inflammatory genetic disease characterized by elevated systemic reactivity against the commensal gut microbiota and high levels of Candida albicans in the gut. This study's major objective was to investigate the effects of commercial probiotic Narine on the relative abundance of gut bacteria (specifically, enterobacteria, lactobacilli, Staphylococcus aureus, and enterococci) of C. albicans carrier and non-carrier FMF patients in remission. Our main finding indicates that the probiotic reduces numbers of C. albicans and abundance of enterobacteria in male and female patients of C. albicans carriers and non-carriers. It has pivotal effect on Enterococcus faecalis: increase in male non-carriers and decrease in female ones regardless of C. albicans status. No effect was seen for Lactobacillus and S. aureus. Our data suggest that M694V/V726A pyrin inflammasome mutations leading to FMF disease may contribute to gender-specific differences in microbial community structure in FMF patients. The study's secondary objective was to elucidate the gender-specific differences in the gut's microbial community of FMF patients. The tendency was detected for higher counts of enterobacteria in female FMF subjects. However, the small number of patients of these groups preclude from conclusive statements, pointing at the need for additional investigations with appropriate for statistical analysis groups of subjects involved in the study.

Antibiotic resistance and recurrence of bacterial vaginosis (BV), a polymicrobial infection, justify the need for novel antimicrobials to counteract microbial resistance to conventional antibiotics. Previously, two series of cationic amphiphiles (CAms) which self-assemble into supramolecular nanostructures with membrane-lytic properties were designed with hydrophilic head groups and nonpolar domains. The combination of CAms and commonly prescribed antibiotics is suggested as a promising strategy for targeting microorganisms that are resistant to conventional antibiotics. Activities of the CAms against Gardnerella vaginalis ATCC 14018, a representative BV pathogen, ranged from 1.1 to 24.4 μM. Interestingly, the tested healthy Lactobacillus species, especially Lactobacillus plantarum ATCC 39268, were significantly more tolerant of CAms than the selected pathogens. In addition, CAms prevented biofilm formation at concentrations which did not influence the normal growth ability of G. vaginalis ATCC 14018. Furthermore, the biofilm minimum bactericidal concentration (MBC-Bs) of CAms against G. vaginalis ATCC 14018 ranged from 58.8 to 425.6 μM, while much higher concentrations (≥850 μM) were required to produce ≥3-log reductions in the number of biofilm-associated lactobacilli. The conventional antibiotic metronidazole synergized strongly with all tested CAms against planktonic cells and biofilms of G. vaginalis ATCC 14018. The synergism between CAms and the tested conventional antibiotic may be considered a new, effective, and beneficial method of controlling biofilm-associated bacterial vaginosis.

Inspired by high promise using naturally occurring antimicrobial peptides (AMPs) to treat infections caused by antimicrobial-resistant bacteria, cationic amphiphiles (CAms) were strategically designed as synthetic mimics to overcome associated limitations, including high manufacture cost and low metabolic stability. CAms with facially amphiphilic conformation were expected to demonstrate membrane-lytic properties and thus reduce tendency of resistance development. By systematically tuning the hydrophobicity, CAms with optimized compositions exhibited potent broad-spectrum antimicrobial activity (with minimum inhibitory concentrations in low μg/mL range) as well as negligible hemolytic activity. Electron microscope images revealed the morphological and ultrastructure changes of bacterial membranes induced by CAm treatment and validated their membrane-disrupting mechanism. Additionally, an all-atom molecular dynamics simulation was employed to understand the CAm-membrane interaction on molecular level. This study shows that these CAms can serve as viable scaffolds for designing next generation of AMP mimics as antimicrobial alternatives to combat drug-resistant pathogens.

Simple Summary: Plant-derived compounds, also known as phytogenics, are gaining popularity in the poultry industry as an effective replacement for antibiotic growth promoters, whose wide and irrational use damages the ecosystem and health of animals and humans. Phytogenics are known for improving poultry's health and production performance. These effects are closely related to the cecal microbiota of chickens, which highlights the importance of studying the effects of any feed additive related to gut microbial communities. In this study, we assessed the effects of a phytogenic blend with and without casein in high amounts on cecal microbiota composition and diversity using an artificial gastrointestinal system (CALIMERO-2) that mimics the physiology of a chicken's cecum. The phytogenic blend promoted the abundance of bacteria associated with energy metabolism and production performance in poultry and decreased the presence of opportunistic pathogens. This study showed promising feed additives that can be used as growth promoters for poultry; however, testing in living broiler chickens to prove these data is needed, as artificial GI systems cannot fully reproduce the intestinal physiology of animals. Phytogenic blends (PBs) consist of various bioactive plant-derived compounds that are used as growth promoters for farm animals. Feed additives based on PBs have beneficial effects on farm animals' production performance, health, and overall well-being, as well as positive modulating effects on gut microbiota. In this study, we used a validated in vitro cecal chicken alimentary tract model (CALIMERO-2) to evaluate the effects of a PB (a mix of components found in rosemary, cinnamon, curcuma, oregano oil, and red pepper), alone or in combination with casein (control), on poultry cecal microbiota. Supplementation with the PB significantly increased the abundance of bacteria associated with energy metabolism (Monoglobus) and growth performance in poultry (Lachnospiraceae UCG-010). The PB also decreased the abundance of opportunistic pathogens (Escherichia-Shigella) and, most importantly, did not promote other opportunistic pathogens, which indicates the safety of this blend for poultry. In conclusion, the results of this study show promising perspectives on using PBs as feed additives for poultry, although further in vivo studies need to prove these data. [ABSTRACT FROM AUTHOR]