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Scientific Reports Jun 2023The aim of this study was to evaluate the effect of Lactobacillus delbrueckii subsp. lactis (L.del) on vaginal microbiota (VM) dysbiosis and vaginal radiation injury in... (Randomized Controlled Trial)
Randomized Controlled Trial
The aim of this study was to evaluate the effect of Lactobacillus delbrueckii subsp. lactis (L.del) on vaginal microbiota (VM) dysbiosis and vaginal radiation injury in gynecologic cancer patients. The inhibitory effects of L.del on cervical cancer cells were also studied in vitro. Gynecologic cancer patients receiving radiotherapy were randomized into control and L.del intervention groups. The control group received radiotherapy, while the intervention group received radiotherapy and L.del intervention (1 capsule/day placed into the deep vagina from the first day of radiotherapy until the end of treatment). Vaginal swab samples were collected on the first day pre-treatment and the last day post-treatment. DNA from 54 patients was extracted and assessed by the 16S rRNA sequencing method. Radiotherapy resulted in vaginal microbiome dysbiosis characterized by increased phylogenetic diversity and increased abundance of Brevundimonas, Streptococcus and Prevotella, but a decreased abundance of Lactobacillus. Level 2 vaginal radiation injury was positively associated with the abundance of Brevundimonas and gram-negative non-fermenting bacteria. Administration of L.del attenuated the reduction of Lactobacillus while also inhibiting the abundance of Streptococcus and Prevotella, thereby ameliorating radiotherapy-related vaginal microbiota dysbiosis. CLD inhibited the in vitro proliferation of SiHa cells by altering the expression of BCL2, HPV16-E6, HPV16-E7, IL6, MAP7, BAX, Caspase-3, Caspase-9 and LTF. In conclusion, L. del application can alleviate radiation-induced vaginal dysbiosis and restore Lactobacillus dominance of the vaginal microbiome. Moreover, CLD was found to inhibit cell growth and promote the apoptosis of SiHa cells in vitro. The registration number for this clinical trial is ChiCTR1900021784.
Topics: Female; Humans; Dysbiosis; RNA, Ribosomal, 16S; Phylogeny; Vagina; Lactobacillus; Streptococcus; Neoplasms
PubMed: 37344615
DOI: 10.1038/s41598-023-37241-7 -
Microbiology Spectrum Jun 2023To increase knowledge on pathogens, we conducted in-depth genomic and phenotypic characterization of a strain isolated from the cerebrospinal fluid of a patient...
To increase knowledge on pathogens, we conducted in-depth genomic and phenotypic characterization of a strain isolated from the cerebrospinal fluid of a patient admitted in a neonatal intensive care unit. The strain was identified as a member of the genus based on Vitek 2 system results and 16S rRNA gene sequencing and presented a multidrug resistance profile (MDR). Several molecular and biochemical tests were used to characterize and identify the species for in-depth results. The draft genome assembly of the isolate has a total length of 3,261,074 bp and a G+C of 66.86%, similar to other species of the genus. Multilocus sequence analysis, Type (Strain) Genome Server, digital DNA-DNA hybridization, and average nucleotide identity confirmed that the sp. studied represents a distinct species, for which we propose the name sp. nov. analysis detected antimicrobial resistance genes (AMRGs) mediating resistance to β-lactams (, , and ) and aminoglycosides [, , , and ]. We also found AMRGs encoding the AcrAB efflux pump that confers resistance to a broad spectrum of antibiotics. Colistin and quinolone resistance can be attributed to mutation in and/or and GyrA/GyrB, respectively. The sp. nov. genome contained copies of type IV secretion system (T4SS)-type integrative and conjugative elements (ICEs); integrative mobilizable elements (IME); and Tn-type and IS, IS, IS, and IS families, suggesting an important role in the development and dissemination of antibiotic resistance. The isolate presented a range of virulence-associated genes related to biofilm formation, adhesion, and invasion that can be relevant for its pathogenicity. Our findings provide a wealth of data to hinder the transmission of MDR and highlight the need for monitoring and identifying new bacterial species in hospital environments. species is considered an opportunistic human pathogen that can cause multiple types of invasive and severe infections in patients with underlying pathologies. Treatment of these pathogens has become a major challenge because many isolates are resistant to most antibiotics used in clinical practice. Furthermore, there are no consistent therapeutic results demonstrating the efficacy of antibacterial agents. Although considered a rare pathogen, recent studies have provided evidence of the emergence of in clinical settings. Hence, we identified a novel pathogenic bacterium, sp. nov., that presented a multidrug resistance (MDR) profile and carried diverse genes related to drug resistance, virulence, and mobile genetic elements. Such data can serve as a baseline for understanding the genomic diversity, adaptation, evolution, and pathogenicity of MDR
Topics: Infant, Newborn; Humans; RNA, Ribosomal, 16S; Brazil; Anti-Bacterial Agents; Colistin; DNA
PubMed: 37067439
DOI: 10.1128/spectrum.04415-22 -
International Journal of Molecular... Nov 2023Drought stress is a significant threat to agricultural productivity and poses challenges to plant survival and growth. Research into microbial plant biostimulants faces...
Drought stress is a significant threat to agricultural productivity and poses challenges to plant survival and growth. Research into microbial plant biostimulants faces difficulties in understanding complicated ecological dynamics, molecular mechanisms, and specificity; to address these knowledge gaps, collaborative efforts and innovative strategies are needed. In the present study, we investigated the potential role of (S1T13) as a microbial plant biostimulant to enhance drought tolerance in . We assessed the impact of S1T13 on Col-0 wild-type (WT) and mutant plants under drought conditions. Our results revealed that the inoculation of S1T13 significantly contributed to plant vigor, with notable improvements observed in both genotypes. To elucidate the underlying mechanisms, we studied the role of ROS and their regulation by antioxidant genes and enzymes in plants inoculated with S1T13. Interestingly, the inoculation of S1T13 enhanced the activities of GSH, SOD, POD, and PPO by 33, 35, 41, and 44% in WT and 24, 22, 26, and 33% in , respectively. In addition, S1T13 upregulated the expression of antioxidant genes. This enhanced antioxidant machinery played a crucial role in neutralizing ROS and protecting plant cells from oxidative damage during drought stress. Furthermore, we investigated the impact of S1T13 on ABA and drought-stress-responsive genes. Similarly, S1T13 modulated the production of ABA and expression of , , , and by 31, 42, 37, 41, and 42% in WT and 20, 29, 27, 38, and 29% in . The improvement in plant vigor, coupled with the induction of the antioxidant system and modulation of ABA, indicates the pivotal role of S1T13 in enhancing the drought stress tolerance of the plants. Conclusively, the current study provides valuable insights for the application of multitrait S1T13 as a novel strain to improve drought stress tolerance in plants and could be added to the consortium of biofertilizers.
Topics: Arabidopsis; Antioxidants; Droughts; Reactive Oxygen Species; Stress, Physiological; Arabidopsis Proteins; Plants, Genetically Modified; Gene Expression Regulation, Plant; Abscisic Acid; Plant Proteins
PubMed: 38068913
DOI: 10.3390/ijms242316590 -
Viruses Apr 2024Previous studies have identified diverse bacteriophages that infect strain CB15 ranging from small RNA phages to four genera of jumbo phages. In this study, we focus on...
Previous studies have identified diverse bacteriophages that infect strain CB15 ranging from small RNA phages to four genera of jumbo phages. In this study, we focus on 20 bacteriophages whose genomes range from 40 to 60 kb in length. Genome comparisons indicated that these diverse phages represent six phage genera and one additional genus that includes both and phages. Within species, comparisons revealed that both single base changes and inserted or deleted genetic material cause the genomes of closely related phages to diverge. Among genera, the basic gene order and the orientation of key genes were retained with most of the observed variation occurring at ends of the genomes. We hypothesize that the nucleotide sequences of the ends of these phage genomes are less important than the need to maintain the size of the genome and the stability of the corresponding mRNAs.
Topics: Genome, Viral; Bacteriophages; Caulobacter; Phylogeny; Evolution, Molecular; Gene Order
PubMed: 38675982
DOI: 10.3390/v16040641 -
AMB Express Jul 2023A novel red-pigmented bacterium was isolated from a water sample collected at Osun River, Ede. Morphological and 16 S rRNA gene sequencing revealed that the bacterium...
A novel red-pigmented bacterium was isolated from a water sample collected at Osun River, Ede. Morphological and 16 S rRNA gene sequencing revealed that the bacterium is a strain of Brevundimonas olei, while its red pigment was identified using UV-visible, FTIR and GCMS as a derivative of propylprodigiosin. The maximum absorbance of 534 nm, the FTIR's 1344 cm peak of prodigiosin's methoxyl C-O interaction, and the molecular ions from GCMS confirmed the pigment's identity. The pigments production was temperature-sensitive (25 °C), lost at > 28 °C, and in the presence of urea and humus. In addition, the pigment turned pink in the presence of hydrocarbons, while its red colour was retained with KCN and FeSO and enhanced by methylparaben. Furthermore, the pigment is stable in high temperature, salt, and acidic conditions, but changed to yellow in alkaline solution. The pigment, identified as propylprodigiosin (m/z 297), demonstrated broad-spectrum antibacterial activities against clinically important strains of Staphylococcus aureus (ATCC25923), Pseudomonas aeruginosa (ATCC9077), Bacillus cereus (ATCC10876), Salmonella typhi (ATCC13311), and Escherichia coli (DSM10974). The ethanol extract has the highest zones of inhibition of 29 ± 3.0, 26 ± 1.2, 22 ± 3.0, 22 ± 1.5, and 20 ± 2.0 mm, respectively. Furthermore, the acetone pigments interacted with cellulose and glucose such that increasing glucose concentrations showed linearity at 425 nm. Finally, the fastness of the pigments to fabrics was excellent, with percentage fadedness of 0 and - 43% light and washing tests, respectively, in the presence of FeSO as the mordant. The antibacterial nature of prodigiosin solutions and their good textile fastness to fabrics could be essential in manufacturing antiseptic materials such as bandages, hospital clothing and agricultural applications such as tubers preservation.Key points.
PubMed: 37422847
DOI: 10.1186/s13568-023-01579-y -
Scientific Reports Feb 2024Extensive research has provided a wealth of data on prokaryotes in caves and their role in biogeochemical cycles. Ice caves in carbonate rocks, however, remain enigmatic...
Extensive research has provided a wealth of data on prokaryotes in caves and their role in biogeochemical cycles. Ice caves in carbonate rocks, however, remain enigmatic environments with limited knowledge of their microbial taxonomic composition. In this study, bacterial and archaeal communities of the Obstans Ice Cave (Carnic Alps, Southern Austria) were analyzed by next-generation amplicon sequencing and by cultivation of bacterial strains at 10 °C and studying their metabolism. The most abundant bacterial taxa were uncultured Burkholderiaceae and Brevundimonas spp. in the drip water, Flavobacterium, Alkanindiges and Polaromonas spp. in the ice, Pseudonocardia, Blastocatella spp., uncultured Pyrinomonadaceae and Sphingomonadaceae in carbonate precipitates, and uncultured Gemmatimonadaceae and Longimicrobiaceae in clastic cave sediments. These taxa are psychrotolerant/psychrophilic and chemoorganotrophic bacteria. On a medium with Mg/Ca = 1 at 21 °C and 10 °C, 65% and 35% of the cultivated strains precipitated carbonates, respectively. The first ~ 200 µm-size crystals appeared 2 and 6 weeks after the start of the cultivation experiments at 21 °C and 10 °C, respectively. The crystal structure of these microbially induced carbonate precipitates and their Mg-content are strongly influenced by the Mg/Ca ratio of the culture medium. These results suggest that the high diversity of prokaryotic communities detected in cryogenic subsurface environments actively contributes to carbonate precipitation, despite living at the physical limit of the presence of liquid water.
Topics: Archaea; Bacteria; Calcium Carbonate; Ice; Phylogeny; Extremophiles
PubMed: 38302670
DOI: 10.1038/s41598-024-53131-y -
Cell Reports. Medicine Dec 2023Allergen-specific immunotherapy (AIT) has shown beneficial effects against atopic dermatitis (AD); however, the mechanisms and parameters underlying the efficacy of AIT...
Allergen-specific immunotherapy (AIT) has shown beneficial effects against atopic dermatitis (AD); however, the mechanisms and parameters underlying the efficacy of AIT remain unclear. Here, we report that the community structure and function of the oral and gut microbiota are changed in patients with AD undergoing AIT. Transplantation of fecal microbiota from patients who respond well to AIT improves AD-like dermatitis in mice. The abundance of Brevundimonas vesicularis in the gut of AD patients has been found to be positively correlated with disease severity and is decreased following AIT. Furthermore, we find that B. vesicularis from the oral cavity might ectopically colonize the gut of AD patients. In AD model mice, meanwhile, B. vesicularis promotes the skewing of the Treg/Th17 balance toward Th17 polarization and attenuates the efficacy of ovalbumin-specific immunotherapy. Our findings provide potential strategies for the optimization of AIT for AD via the modulation of the gut microbiota.
Topics: Humans; Mice; Animals; Dermatitis, Atopic; Desensitization, Immunologic; Allergens; Intestines
PubMed: 38118418
DOI: 10.1016/j.xcrm.2023.101340 -
Frontiers in Microbiology 2023In order to develop environment friendly microbial inhibitor that can also control disease and promote oat () growth, the growth rate method and response surface...
In order to develop environment friendly microbial inhibitor that can also control disease and promote oat () growth, the growth rate method and response surface methodology were used to screen wetting agents, preservatives and protective agents at optimal concentrations in this study. Antagonistic activity of the tested bacterium and cell-free fermentation liquid against pathogenic fungi was evaluated on potato dextrose agar (PDA) substratum plates by dual culture technique. Oxford cup method was used to measure antagonistic reaction between screened bacteria. According to each screened bacteria with 50 mL were mixed and cultured in Luria-bertani (LB) substratum. Additives of Wetting agents, UV-protectors, and preservatives were screened by single factor test on the growth concentration of screened mixed bacteria. Afterwards, the optimal additives and concentrations were screened by Box-Behnken method. The microbial inhibitor was detected according to national standards GB20287-2006 and tested on oat in a pot experiment. The results showed that: (1) Functional bacteria which including and had control effects of 50.00% to 83.29% on three pathogenic fungi, and their cell free-fermentation liquid could inhibit the growth of pathogenic fungi from 23.51% to 39.90%; (2) Tween-80 was most suitable as wetting agents for Mix biocontrol bacteria (MBB) with 1.00% mass fraction; Sorbitol was selected as UV protective agents for MBB with 0.50% mass fraction. And methyl paraben was used as a preservative for MBB, with 0.50% mass fraction; (3) The most effective adjuvant contained 14.96 mL/L Tween-80, 5.12 g/L methylparaben and 5.6 g/L sorbitol; and (4) The microbial inhibitor controlled 45.57% of oat root rot and increased plant height, root length and seedling biomass. This study provides a suitable environment for the protection of mixed biocontrol bacteria, and lays a foundation for the prevention and control of oat diseases, the promotion of growth and the improvement of quality.
PubMed: 37547695
DOI: 10.3389/fmicb.2023.1208591 -
BMC Microbiology Dec 2023Orthokeratology (OK) lens wear increases the risk of bacterial infection, but little is known about the microbiota of the conjunctival sac in myopic children wearing OK...
BACKGROUND
Orthokeratology (OK) lens wear increases the risk of bacterial infection, but little is known about the microbiota of the conjunctival sac in myopic children wearing OK lenses. This study aimed to investigate the changes of conjunctival microbiota in children after treatment with OK lenses using 16 S rDNA sequencing.
METHODS
Twenty-eight myopic children who had been continuously wearing OK lenses for 12 to 13 months were enrolled in this prospective study. Twenty-two gender- and age-matched myopic children who had not worn OK lenses or discontinued OK lens wear at least 1 year ago were recruited as controls. Conjunctival swabs from each participant were collected for exploration of the microbiota profiles, targeting the V3-V4 regions of the 16 S rRNA gene by MiSeq sequencing. The differences in the microbial community structure and diversity were also compared between groups.
RESULTS
The bacterial alpha diversity indices in the OK lens group were not different from those in the non-wearer group (P > 0.05, Wilcoxon test), while beta diversity examined using principle coordinate analysis of unweighted UniFrac divided the two groups into different clusters. Proteobacteria, Bacteroidetes, and Firmicutes were the abundant phyla in the conjunctival sac microbiota in both groups (P < 0.05, Mann-Whitney U test). Among children in the OK lens group, the Linear discriminant analysis Effect Size identified the compositional changes in OK lens-associated bacteria. Key functional genera such as Blautia, Parasutterella, and Muribaculum were enriched, whereas Brevundimonas, Acinetobacter, Proteus, and Agathobacter decreased significantly (P < 0.05, Mann-Whitney U test). Phylogenetic investigation of communities by reconstruction of unobserved states also showed altered bacterial metabolic pathways in OK lens-associated microbiota. Moreover, using receiver operating characteristic curves, Brevundimonas, Acinetobacter, Proteus, and Agathobacter alone (the area under the curve was all > 0.7500) or in combination (the area under the curve was 0.9058) were revealed to discriminate OK lens wearers from controls.
CONCLUSIONS
The relative abundance of the microbial community in the conjunctival sac of myopic children can alter after OK lens wear. Brevundimonas, Acinetobacter, Proteus, and Agathobacter may be candidate biomarkers to distinguish between OK lens wearers and non-wearers.
Topics: Child; Humans; Prospective Studies; Phylogeny; Contact Lenses; Myopia; Bacteria; Microbiota
PubMed: 38087200
DOI: 10.1186/s12866-023-03042-1 -
PloS One 2023As a strategy for minimizing microbial infections in fish hatcheries, we have investigated how putatively probiotic bacterial populations influence biofilm formation....
As a strategy for minimizing microbial infections in fish hatcheries, we have investigated how putatively probiotic bacterial populations influence biofilm formation. All surfaces that are exposed to the aquatic milieu develop a microbial community through the selective assembly of microbial populations into a surface-adhering biofilm. In the investigations reported herein, we describe laboratory experiments designed to determine how initial colonization of a surface by nonpathogenic isolates from sturgeon eggs influence the subsequent assembly of populations from a pelagic river community, into the existing biofilm. All eight of the tested strains altered the assembly of river biofilm in a strain-specific manner. Previously formed isolate biofilm was challenged with natural river populations and after 24 hours, two strains and two-isolate combinations proved highly resistant to invasion, comprising at least 80% of the biofilm community, four isolates were intermediate in resistance, accounting for at least 45% of the biofilm community and two isolates were reduced to 4% of the biofilm community. Founding biofilms of Serratia sp, and combinations of Brevundimonas sp.-Hydrogenophaga sp. and Brevundimonas sp.-Acidovorax sp. specifically blocked populations of Aeromonas and Flavobacterium, potential fish pathogens, from colonizing the biofilm. In addition, all isolate biofilms were effective at blocking invading populations of Arcobacter. Several strains, notably Deinococcus sp., recruited specific low-abundance river populations into the top 25 most abundant populations within biofilm. The experiments suggest that relatively simple measures can be used to control the assembly of biofilm on the eggs surface and perhaps offer protection from pathogens. In addition, the methodology provides a relatively rapid way to detect potentially strong ecological interactions between bacterial populations in the formation of biofilms.
Topics: Animals; Rivers; Biofilms; Flavobacterium; Bacteria, Aerobic; Fishes
PubMed: 37956125
DOI: 10.1371/journal.pone.0288040