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Frontiers in Microbiology 2021Four strains belonging to the family of were isolated from different locations on the International Space Station (ISS) across two consecutive flights. Of these, three...
Four strains belonging to the family of were isolated from different locations on the International Space Station (ISS) across two consecutive flights. Of these, three were identified as Gram-negative, rod-shaped, catalase-positive, oxidase-positive, motile bacteria, designated as IF7SW-B2, IIF1SW-B5, and IIF4SW-B5, whereas the fourth was identified as . The sequence similarity of these three ISS strains, designated as IF7SW-B2, IIF1SW-B5, and IIF4SW-B5, was <99.4% for 16S rRNA genes and <97.3% for gene, with the closest being SE2.11. Furthermore, the multi-locus sequence analysis placed these three ISS strains in the same clade of The average nucleotide identity (ANI) values of these three ISS strains were <93% and digital DNA-DNA hybridization (dDDH) values were <46.4% with any described species. Based on the ANI and dDDH analyses, these three ISS strains were considered as novel species belonging to the genus The three ISS strains showed 100% ANI similarity and dDDH values with each other, indicating that these three ISS strains, isolated during various flights and from different locations, belong to the same species. These three ISS strains were found to grow optimally at temperatures from 25 to 30°C, pH 6.0 to 8.0, and NaCl 0 to 1%. Phenotypically, these three ISS strains resemble and since they assimilate similar sugars as sole carbon substrate when compared to other species. Fatty acid analysis showed that the major fatty acid produced by the ISS strains are C -ω7 and C -ω6. The predominant quinone was ubiquinone 10, and the major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and an unidentified lipid. Therefore, based on genomic, phylogenetic, biochemical, and fatty acid analyses, strains IF7SW-B2, IIF1SW-B5, and IIF4SW-B5, are assigned to a novel species within the genus , and the name sp. nov. is proposed. The type strain is IF7SW-B2 (NRRL B-65601 and LMG 32165).
PubMed: 33790880
DOI: 10.3389/fmicb.2021.639396 -
Microbial Biotechnology Nov 2020Solar panel surfaces can be colonized by microorganisms adapted to desiccation, temperature fluctuations and solar radiation. Although the taxonomic and functional...
Solar panel surfaces can be colonized by microorganisms adapted to desiccation, temperature fluctuations and solar radiation. Although the taxonomic and functional composition of these communities has been studied, the microbial colonization process remains unclear. In the present work, we have monitored this microbial colonization process during 24 months by performing weekly measurements of the photovoltaic efficiency, carrying out 16S rRNA gene high-throughput sequencing, and studying the effect of antimicrobial compounds on the composition of the microbial biocenosis. This is the first time a long-term study of the colonization process of solar panels has been performed, and our results reveal that species richness and biodiversity exhibit seasonal fluctuations and that there is a trend towards an increase or decrease of specialist (solar panel-adapted) and generalist taxa, respectively. On the former, extremophilic bacterial genera Deinococcus, Hymenobacter and Roseomonas and fungal Neocatenulostroma, Symmetrospora and Sporobolomyces tended to dominate the biocenosis; whereas Lactobacillus sp or Stemphyllium exhibited a decreasing trend. This profile was deeply altered by washing the panels with chemical agents (Virkon), but this did not lead to an increase of the solar panels efficiency. Our results show that solar panels are extreme environments that force the selection of a particular microbial community.
Topics: Bacteria; Biodiversity; Extremophiles; Microbiota; Phylogeny; RNA, Ribosomal, 16S
PubMed: 32613706
DOI: 10.1111/1751-7915.13620 -
BMC Microbiology Jan 2022Urogenital microbiota may be associated with the recurrence of bladder cancer, but the underlying mechanism remains unclear. The notion that microbiota can upregulate...
BACKGROUND
Urogenital microbiota may be associated with the recurrence of bladder cancer, but the underlying mechanism remains unclear. The notion that microbiota can upregulate PD-L1 expression in certain epithelial tumors to promote immune escape has been demonstrated. Thus, we hypothesized that the urogenital microbiota may be involved in the recurrence and progression of non-muscle invasive bladder cancer (NMIBC) by upregulating the PD-L1 expression. To test this hypothesis, we investigated the relationship between urogenital microbial community and PD-L1 expression in male patients with NMIBC.
RESULTS
16S rRNA gene sequencing was performed to analyse the composition of urogenital microbiota, and the expression of PD-L1 in cancerous tissues was detected by immunohistochemistry. The subjects (aged 43-79 years) were divided into PD-L1-positive group (Group P, n = 9) and PD-L1-negative group (Group N, n = 19) respectively based on their PD-L1 immunohistochemical results. No statistically significant differences were found in the demographic characteristics between group P and N. We observed that group P exhibited higher species richness (based on Observed species and Ace index, both P < 0.05). Furthermore, subgroup analysis showed that the increase in number of PD-L1 positive cells was accompanied by increased richness of urogenital microbiota. Significantly different composition of urogenital microbiota was found between group P and group N (based on weighted Unifrac and unweighted Unifrac distances metric, both P < 0.05). Enrichment of some bacterial genera (e.g., Leptotrichia, Roseomonas, and Propionibacterium) and decrease of some bacterial genera (e.g., Prevotella and Massilia) were observed in group P as compared with group N. These findings indicated that these genera may affect the expression of PD-L1 through some mechanisms to be studied.
CONCLUSION
Our study provided for the first time an overview of the association between urogenital microbiota and PD-L1 expression in male patients with NMIBC, indicating that urogenital microbiota was an important determinant of PD-L1 expression in male NMIBC patients.
Topics: Adult; Aged; B7-H1 Antigen; Bacteria; Disease Progression; Humans; Male; Microbiota; Middle Aged; Recurrence; Urinary Bladder Neoplasms; Urogenital System
PubMed: 34983384
DOI: 10.1186/s12866-021-02407-8 -
Journal of Ophthalmic Inflammation and... Dec 2017Endogenous bacterial endophthalmitis is an infrequently reported entity. Although Roseomonas mucosa has been reported to cause systemic infections in immunosuppressed...
BACKGROUND
Endogenous bacterial endophthalmitis is an infrequently reported entity. Although Roseomonas mucosa has been reported to cause systemic infections in immunosuppressed individuals, ocular infection due to Roseomonas has been rarely reported in literature previously.
FINDINGS
A 74-year-old diabetic was diagnosed to have Klebsiella urinary tract infection and septicemia following which he developed ocular pain and redness. Further investigation revealed endophthalmitis with subretinal abscess and retinal detachment. The patient underwent pars plana vitrectomy with drainage of the abscess and silicone oil tamponade. The subretinal aspirate was found to contain R. mucosa confirmed on culture and PCR.
CONCLUSION
Microbiological evaluation of the subretinal purulent material revealed pink-colored colonies. Nested PCR was positive for detection of the eubacterial genome as well as for detection of the Mycobacterium tuberculosis genome (Ref)-targeting MPB64 gene. PCR examination of the subretinal pus sample ruled out M. tuberculosis and confirmed R. mucosa. The occurrence of Roseomonas endogenous endophthalmitis presenting as a subretinal abscess has not yet been reported in English literature so far to the best of our knowledge.
PubMed: 28130734
DOI: 10.1186/s12348-017-0123-6 -
FEMS Microbiology Letters Jan 2023Methylobacterium species are abundant colonizers of the phyllosphere due to the availability of methanol, a waste product of pectin metabolism during plant cell...
Methylobacterium species are abundant colonizers of the phyllosphere due to the availability of methanol, a waste product of pectin metabolism during plant cell division. The phyllosphere is an extreme environment, with a landscape that is heterogeneous and continuously changing as the plant grows and is exposed to high levels of ultraviolet irradiation. Geographically, New Zealand (NZ) has been isolated for over a million years, has a biologically diverse flora, and is considered a biodiversity hotspot, with most native plants being endemic. We therefore hypothesize that the phyllosphere of NZ native plants harbor diverse groups of Methylobacterium species. Leaf imprinting using methanol-supplemented agar medium was used to isolate bacteria, and diversity was determined using ARDRA and 16S rRNA gene sequencing. Methylobacterium species were successfully isolated from the phyllosphere of 18 of the 20 native NZ plant species in this study, and six different species were identified: M. marchantiae, M. mesophilicum, M. adhaesivum, M. komagatae, M. extorquens, and M. phyllosphaerae. Other α, β, and γ-Proteobacteria, Actinomycetes, Bacteroidetes, and Firmicutes were also isolated, highlighting the presence of other potentially novel methanol utilizers within this ecosystem. This study identified that Methylobacterium are abundant members of the NZ phyllosphere, with species diversity and composition dependent on plant species.
Topics: Methylobacterium; Ecosystem; RNA, Ribosomal, 16S; Methanol; New Zealand; Plants; Plant Leaves
PubMed: 37985695
DOI: 10.1093/femsle/fnad124 -
Access Microbiology Mar 2021Both bacterial and aseptic meningitis can complicate neurosurgery, but they are often difficult to distinguish clinically or by cerebrospinal fluid (CSF) analysis. We...
Both bacterial and aseptic meningitis can complicate neurosurgery, but they are often difficult to distinguish clinically or by cerebrospinal fluid (CSF) analysis. We present an adolescent with subacute meningitis after neurosurgery, eventually diagnosed with meningitis caused by via 16S rRNA gene sequencing after two negative CSF cultures. He was treated successfully with intravenous meropenem with full recovery. This case shows that distinguishing bacterial from aseptic meningitis is important to allow directed antibiotic therapy. We recommend considering bacterial meningitis in the differential diagnosis of aseptic meningitis complicating neurosurgery, and to perform molecular diagnostics such as bacterial sequencing if the suspicion of bacterial meningitis is high.
PubMed: 34151165
DOI: 10.1099/acmi.0.000213 -
The ISME Journal Nov 2018Microbes frequently rely on metabolites excreted by other bacterial species, but little is known about how this cross-feeding influences the effect of antibiotics. We...
Microbes frequently rely on metabolites excreted by other bacterial species, but little is known about how this cross-feeding influences the effect of antibiotics. We hypothesized that when species rely on each other for essential metabolites, the minimum inhibitory concentration (MIC) for all species will drop to that of the "weakest link"-the species least resistant in monoculture. We tested this hypothesis in an obligate cross-feeding system that was engineered between Escherichia coli, Salmonella enterica, and Methylobacterium extorquens. The effect of tetracycline and ampicillin were tested on both liquid and solid media. In all cases, resistant species were inhibited at significantly lower antibiotic concentrations in the cross-feeding community than in monoculture or a competitive community. However, deviation from the "weakest link" hypothesis was also observed in cross-feeding communities apparently as result of changes in the timing of growth and cross-protection. Comparable results were also observed in a clinically relevant system involving facultative cross-feeding between Pseudomonas aeruginosa and an anaerobic consortium found in the lungs of cystic fibrosis patients. P. aeruginosa was inhibited by lower concentrations of ampicillin when cross-feeding than when grown in isolation. These results suggest that cross-feeding significantly alters tolerance to antibiotics in a variety of systems.
Topics: Ampicillin; Anti-Bacterial Agents; Cystic Fibrosis; Drug Resistance, Bacterial; Escherichia coli; Humans; Methylobacterium extorquens; Pseudomonas aeruginosa; Salmonella enterica; Tetracycline
PubMed: 29991761
DOI: 10.1038/s41396-018-0212-z -
Current Research in Translational... 2023Fetal growth restriction (FGR) is a complex obstetric complication with various causes and of great harm. However, the specific pathogenesis of FGR is unclear, which...
BACKGROUND
Fetal growth restriction (FGR) is a complex obstetric complication with various causes and of great harm. However, the specific pathogenesis of FGR is unclear, which limits its effective treatment. Gut microbiota dysbiosis was found to be important in pathogenesis of various diseases. However, its role in FGR development remains unclear and needs to be clarified.
METHODS
In our case-control study, we recruited eight FGR and eight control female participants and collected their fecal samples in third trimester before delivery. We performed metagenomic sequencing and bioinformatic analysis to compare the gut microbiota composition and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways between the two groups.
RESULTS
Our results showed that totally 20 gut microbes were significantly different between two groups (p<0•05), and the correlation analysis found that g__Roseomonas and g__unclassified_f__Propionibacteriaceae were significantly positive correlated with both maternal body mass index (BMI) before delivery, placental weight, and neonatal birth weight (BW) percentile (all p<0•05), while g__Marinisporobacter and g__Sphingomonas were significantly negative correlated with both neonatal BMI and neonatal BW percentile (all p<0•05). Through KEGG pathway analysis, we found that the abundance of the Nitrogen metabolism pathway decreased significantly (p<0•05) whereas the abundance of the Amoebiasis pathway increased significantly in the FGR group (p<0•05).
CONCLUSION
In this study, we demonstrated that the occurrence of FGR is associated with the change of gut microbiota of pregnant women.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Fetal Growth Retardation; Placenta; Case-Control Studies; Microbiota; Gastrointestinal Microbiome
PubMed: 36434943
DOI: 10.1016/j.retram.2022.103354 -
Science Translational Medicine Sep 2020Dysbiosis of the skin microbiota is increasingly implicated as a contributor to the pathogenesis of atopic dermatitis (AD). We previously reported first-in-human safety... (Randomized Controlled Trial)
Randomized Controlled Trial
Dysbiosis of the skin microbiota is increasingly implicated as a contributor to the pathogenesis of atopic dermatitis (AD). We previously reported first-in-human safety and clinical activity results from topical application of the commensal skin bacterium for the treatment of AD in 10 adults and 5 children older than 9 years of age. Here, we examined the potential mechanism of action of treatment and its impact on children with AD less than 7 years of age, the most common age group for children with AD. In 15 children with AD, treatment was associated with amelioration of disease severity, improvement in epithelial barrier function, reduced burden on the skin, and a reduction in topical steroid requirements without severe adverse events. Our observed response rates to treatment were greater than those seen in historical placebo control groups in prior AD studies. Skin improvements and colonization by persisted for up to 8 months after cessation of treatment. Analyses of cellular scratch assays and the MC903 mouse model of AD suggested that production of sphingolipids by , cholinergic signaling, and flagellin expression may have contributed to therapeutic impact through induction of a TNFR2-mediated epithelial-to-mesenchymal transition. These results suggest that a randomized, placebo-controlled trial of treatment in individuals with AD is warranted and implicate commensals in the maintenance of the skin epithelial barrier.
Topics: Adult; Child; Dermatitis, Atopic; Eczema; Humans; Lipids; Methylobacteriaceae; Skin
PubMed: 32908007
DOI: 10.1126/scitranslmed.aaz8631 -
Frontiers in Oral Health 2022Biofilm formation in dental unit waterlines and the resulting microbial contamination of the water in the system has become a significant problem. Contaminated water in...
Biofilm formation in dental unit waterlines and the resulting microbial contamination of the water in the system has become a significant problem. Contaminated water in the dental units is a major concern in dental clinics due to potential risk of causing infections particularly in elderly and immunocompromised patients. The aim of this study was at first to determine microbial contamination of the dental unit waterlines and then to study the efficacy of a comprehensive disinfection protocol on decreasing the microbial load. Water samples were collected before and after disinfection procedure from handpieces and water storage bottles from the dental units, a small 1-cm tubing was cut from each unit and subjected to microbiological culture on different growth media. Identification of the predominant species was achieved by 16S rRNA gene sequencing. Microbial growth was observed in samples collected from all dental units. Upon disinfection procedure, microbial contamination in the water samples and in the tubing surfaces was significantly reduced ( > 0.05). 16S rRNA gene sequencing revealed the presence of several species belonging to the genera , and , some of which are implicated in human infections. Aggravation of the biofilm growth on the tubing surfaces and the microbial contamination in the water can be effectively controlled by implementing appropriate and routine disinfection protocols. This may help protect the dental unit staff and the patients being exposed to the risk of infections.
PubMed: 36698450
DOI: 10.3389/froh.2022.1071018