Anaerobic Bacteria Research Articles

Oral Microbiocenosis in Cases of Inflammatory Periodontal Diseases in Children with Tuberculosis

Objective — to examine the microbial spectrum of the oral cavity in cases of inflammatory periodontal diseases of children with tuberculosis. Materials and methods. A study of the microbial habitat of oral biotopes and gingival surfaces was conducted in 97 children aged 6 to 17 years with inflammatory periodontal diseases and tuberculosis (treatment group). The control group consisted of 20 practically healthy children of the same age. The periodontal diseases were diagnosed according to M.F. Danilevsky’s classification (2000). The study of oral microbiocenosis and gingival surfaces in the examined groups of children was performed in accordance with Order No. 234 of the Ministry of Health of Ukraine as of 2006. Results and discussion. Aerobic, facultative anaerobic, and anaerobic bacteria persisted in the oral fluid and on the gingival surfaces of children with tuberculosis and inflammatory periodontal diseases. The most frequent colonies of bacteria were Streptococcus, in particular S. mutans, S. salivarius, S. β-haemolyticus, Staphylococcus (S. aureus, S. epidermidis).The significant evidence of Neisseria (N. catarrhalis) and Corynebacterium (C. xerosis) was revealed in the oral cavity and gingival surfaces of the examined children. The microflora of children from the treatment group revealed mostly Lactobacillus genus. The microbial associations of the examined children consisted of Candida, E. coli fungi. Smear microscopy revealed viruses. S. aureus was higher in the children from the treatment group as compared to the healthy children. In addition, the concentration of microorganisms was higher on the gingival surface versus the oral fluid and was more evident in the children from the treatment group. Conclusions. The obtained spectrum of the oral microbial contamination in the children with tuberculosis and inflammatory periodontal diseases revealed the persisting associations of aerobic, facultative anaerobic, and anaerobic bacteria. The inflammatory periodontal diseases in tuberculosis-infected children were accompanied by the evident increase in the frequency and concentration of microorganisms increasing with the higher severity of the specific process.

Analysis of vaginal flora diversity and study on the role of Porphyromonas asaccharolytica in promoting IL-1β in regulating cervical cancer

Cervical cancer, a prevalent malignancy in the female reproductive tract, exhibits a high incidence. Existing evidence indicates a robust correlation between alterations in vaginal flora composition and the progression of cervical cancer. Nevertheless, there is a lack of clarity concerning the specific microorganisms within the vaginal microbiota that are linked to the onset and development of cervical cancer, as well as the mechanisms through which they exert carcinogenic effects. The 16 S ribosomal (rRNA) and metagenomic sequencing technology were used to analyze vaginal microorganisms, and screening for human papillomavirus (HPV) positive cervical cancer-associated microbial markers using fold change in mean bacterial abundance. Moreover, vaginal microenvironmental factors were detected, and the local vaginal inflammatory state in patients with cervical cancer was subjected to assay via qRT-PCR and ELISA. The hub inflammatory genes were screened by transcriptome sequencing after co-culture of bacteria and normal cervical epithelial cells, and an in vitro model was utilized to assess the impacts of inflammatory factors on cervical cancer. Both cervical cancer patients and HPV-positive patients showed significant changes in the composition of the vaginal flora, characterised by a decrease in the abundance of Lactobacillus and an increase in the abundance of a variety of anaerobic bacteria; The microbial sequencing identified Porphyromonas, Porphyromonas_asaccharolytica, and Porphyromonas_uenonis as microbial markers for HPV-associated cervical cancer. Vaginal inflammatory factors in patients with cervical cancer were overexpressed. After Porphyromonas_asaccharolytica intervention on cervical epithelial H8 cells, interleukin (IL)-1β, a hub differential gene, markedly promoted tumor-associated biological behaviors at the in vitro cytological level in cervical cancer. This study for the first demonstrated that Porphyromonas, Porphyromonas_asaccharolytica, and Porphyromonas_uenonis could serve as novel microbial markers for cervical cancer. Moreover, Porphyromonas_asaccharolytica was identified as having the ability to induce the overexpression of inflammatory genes in cervical epithelial cells to create a favorable microenvironment for the onset and development of cervical cancer. The effects of dysbacteriosis on cervical cancer were microbiologically elucidated.

Микробиологические риски как причина пороков внешнего вида сыра

Aerobic Bacillus bacteria, yeasts, and micrococci are pigment-forming microorganisms responsible for color defects in cheese production. The article describes their environment, industry-related characteristics, types of defects they cause, and various color violations in commercial cheeses. The research featured domestic cheeses with yellow and red surface spots that appeared during industrial ripening and storage. Pigment-forming microorganisms developed on cheese surface at a low ripening temperature, high concentration of table salt, and critically low oxygen. Pigment-forming microflora proved to enter cheese from milk, brine, or production environment, e.g., water, air, and processing equipment, dry and succulent feeds being the main source of milk contamination with spore-forming aerobic bacteria, yeast, mold fungi, etc. Contamination of raw milk, milking equipment, and air environment with micrococci was primarily associated with cows’ udder and skin. Cheese production presupposes low-temperature heat treatment of raw milk, which means possible residual microflora in pasteurized milk. As a result, the total count of mesophilic aerobic and optionally anaerobic microorganisms, i.e., the potential pigment formers, was to stay below 104 CFU/cm3. Yeast and spore-forming Bacillus microorganisms demonstrated the acceptable level of ≤102 CFU/cm3 in milk intended for cheesemaking. If their total count exceeded 103 CFU/cm3, it indicated high microbiological risks of cheese appearance defects. The microflora responsible for discoloration of cheese surface was represented by yeast, micrococci, aerobic spores, or their combinations.

A Widespread Radical-Mediated Glycolysis Pathway.

Glycyl radical enzymes (GREs) catalyze mechanistically diverse radical-mediated reactions, playing important roles in the metabolism of anaerobic bacteria. The model bacterium Escherichia coli MG1655 contains two GREs of unknown function, YbiW and PflD, which are widespread among human intestinal bacteria. Here, we report that YbiW and PflD catalyze ring-opening C-O cleavage of 1,5-anhydroglucitol-6-phosphate (AG6P) and 1,5-anhydromannitol-6-phosphate (AM6P), respectively. The product of both enzymes, 1-deoxy-fructose-6-phosphate (DF6P), is then cleaved by the aldolases FsaA or FsaB to form glyceraldehyde-3-phosphate (G3P) and hydroxyacetone (HA), which are then reduced by the NADH-dependent dehydrogenase GldA to form 1,2-propanediol (1,2-PDO). Crystal structures of YbiW and PflD in complex with their substrates provided insights into the mechanism of radical-mediated C-O cleavage. This "anhydroglycolysis" pathway enables anaerobic growth of E. coli on 1,5-anhydroglucitol (AG) and 1,5-anhydromannitol (AM), and we probe the feasibility of harnessing this pathway for the production of 1,2-PDO, a highly demanded chiral chemical feedstock, from inexpensive starch. Discovery of the anhydroglycolysis pathway expands the known catalytic repertoire of GREs, clarifies the hitherto unknown physiological functions of the well-studied enzymes FsaA, FsaB, and GldA, and demonstrates how enzyme discovery efforts can cast light on prevalent yet overlooked metabolites in the microbiome.

Prevalence of bacterial vaginosis and its associated factors among pregnant women attending antenatal care clinics at public hospitals in West Shoa Zone, Oromia, Ethiopia

Bacterial vaginosis is a polymicrobial syndrome characterized by the decrease of Lactobacilli and an overgrowth of facultative and anaerobic bacteria in vaginal fluid. Though it has received little attention, it has been associated with poor pregnancy outcomes, such as pre-term labor and delivery, premature rupture of membranes, low birth weight, spontaneous abortion, and postpartum infections. This study aimed to determine the prevalence of bacterial vaginosis and its associated factors among pregnant women attending antenatal care clinics from September 15 to December 14, 2021, at public hospitals in West Shoa Zone, Oromia, Ethiopia. An institutional-based cross-sectional study was conducted on 260 pregnant women, and systematic random sampling was employed to recruit the study participants. Data were collected through a structured questionnaire and the vaginal swab was collected using a sterile cotton swab. The gram staining result was interpreted using the Nugent scoring system. Data was entered into an Excel spreadsheet and exported to STATA-14 for analysis. Data were presented using tables and graphs. Binary and multivariable logistic regressions were performed. Variables with a P value ≤ 0.25 at the binary logistic regression were entered into the multivariable logistic regression. Finally, variables with a P value ≤ 0.05 were considered predictors of bacterial vaginosis and interpreted using adjusted Odds Ratios (AOR) with a 95% confidence interval (CI). A total of 260 pregnant women attending antenatal care were included in the study. The prevalence of bacterial vaginosis according to the Nugent scoring system was 22.3% (95% CI 17.4 to 27.9%). Pregnant women with other marital status were at reduced risk of bacterial vaginosis as compared with married pregnant women (AOR = 0.260, 95% CI 0.068 to 0.9995; P = 0.05). Rural residence (AOR = 2.1, 95% CI 1.05 to 4.24; P = 0.036), use of one pant per week (AOR = 2.7, 95% CI 1.04 to 7.2; P = 0.041), and use of two or more pants per week (AOR = 4.96, 95% CI 1.49 to 16.57; P = 0.009) were significantly associated with bacterial vaginosis. In the current study, a high magnitude of bacterial vaginosis was reported. Residence, marital status, and number of pants used per week were found significantly associated among pregnant women. Hence, screening for the disease should be integrated into the recommended basic laboratory investigations during antenatal visits.

Advanced N removal from low C/N sewage via a plug-flow anaerobic/oxic/anoxic (AOA) process: Intensification through partial nitrification, endogenous denitrification, partial denitrification, and anammox (PNEnD/A)

Achieving low-cost advanced nitrogen (N) removal from municipal wastewater treatment plants (WWTPs) remains a challenge. A plug-flow anaerobic/oxic/anoxic (AOA) system with a mixtures bypass (MBP) integrating partial nitrification (PN), endogenous carbon denitrification (EnD), partial denitrification (PD), and anaerobic ammonium oxidation (Anammox), was constructed to treat actual sewage with a low C/N ratio. The effluent concentrations and removal efficiency of total inorganic nitrogen (TIN) during stable operation were 2.9 ± 0.9 mg/L and 93.1 ± 2.0 %, respectively. EnD was enhanced by the MBP through the efficient utilization of polyhydroxyalkanoates generated in the anaerobic zone. PD was promoted by the addition of carries and sodium acetate to the anoxic tank and the subsequent implantation of the Anammox biofilm successfully coupled PD/A. Stable PN was obtained with a satisfactory nitrite accumulation ratio of 92.6 %, facilitated by carriers and the introduction of hydroxylamine in the oxic zone. Mass balance analysis revealed that EnD and Anammox contributed 40.8 % and 48.2 % of TIN removal, respectively. The enrichment and synergistic effects of ammonia-oxidizing bacteria, denitrifying bacteria, glycogen-accumulating organisms, and anaerobic ammonia-oxidizing bacteria formed a diverses bacterial basis for the establishment of PN, EnD, PD, and Anammox (PNEnD/A) in the AOA system. The successful integration of PNEnD/A into the AOA process provides an innovative approach for low-cost advanced N removal in WWTPs.

A Metagenomics Pipeline to Characterize Self-Collected Vaginal Microbiome Samples.

Vaginitis is a widespread issue for women worldwide, yet current diagnostic tools are lacking. Bacterial vaginosis (BV) is the most prevalent type of vaginitis, found in 10-50% of reproductive-aged women. Current diagnostic methods for BV rely on clinical criteria, microscopy, or the detection of a few microbes by qPCR. However, many vaginal infections lack a single etiological agent and are characterized by changes in the vaginal microbiome community structure (e.g., BV is defined as a loss of protective lactobacilli resulting in an overgrowth of anaerobic bacteria). Shotgun metagenomic sequencing provides a comprehensive view of all the organisms present in the vaginal microbiome (VMB), allowing for a better understanding of all potential etiologies. Here, we describe a robust VMB metagenomics sequencing test with a sensitivity of 93.1%, a specificity of 90%, a negative predictive value of 93.4%, and a positive predictive value of 89.6% certified by Clinical Laboratory Improvement Amendments (CLIA), the College of American Pathologist (CAP), and the Clinical Laboratory Evaluation Program (CLEP). We sequenced over 7000 human vaginal samples with this pipeline and described general findings and comparisons to US census data.

Water quality index of selected borehole locations in Jos North LGA of Plateau State, Nigeria

Prevalence of water borne diseases is a public health concern. The study assessed the quality of selected borehole waters in Jos North for their potability. The physicochemical parameters were assessed in addition to chlorides, phosphates, nitrates, and sulphates, total solids, total dissolved solids, total suspended solids, total hardness, using standard methods. Atomic absorption spectrophotometry used for elemental analysis of samples for manganese, lead, cadmium, copper and zinc. microbial analysis was carried out to test for presence of anaerobic bacteria, coliforms, Escherichia coli, Salmonella typhi, yeast and mould, Staphylococcus aureus using the plate count method. Water Quality Index by Weighted Arithmetic Index Method. Results ranged from 22.19-56.22 mg/L (chlorides), 0.00-0.07 mg/L (phosphates), 0.11-0.19 mS/cm (conductivity), 141.40-169.40 mg/L (alkalinity) and 86.70-160 mg/L (TSS). Kyan Primary school had Mn 0.632 mg/L against 0.500mg/L recommended by WHO. Microbial analysis revealed that Kyan primary school had 1 cfu per 100 mL water for E. coli, Salmonella typhi, yeast and mould. This indicated faecal contamination. The WQI revealed Village hostel, Kyan Village, Gadabiu had values of 6.54, 19.41, 10.97 are potable, Government College, Angwan Jarawa, Kyan Primary school had 28.90, 61.50, 93.60 are potable, poor, very poor, not potable.

Akkermansia muciniphila as a Potential Guardian against Oral Health Diseases: A Narrative Review.

The oral microbiome is a diverse ecosystem containing a community of symbiotic, commensal, and pathogenic microorganisms. One key microorganism linked to periodontal disease (PD) is Porphyromonas gingivalis (P. gingivalis), a Gram-negative anaerobic bacterium known to have several virulence factors that trigger inflammation and immune evasion. On the other hand, Akkermansia muciniphila (A. muciniphila), a symbiotic bacterium, has been recently shown to play an important role in mitigating inflammation and reducing periodontal damage. In vivo and in vitro studies have shown that A. muciniphila decreases inflammatory mediators and improves immune responses, suggesting its role in mitigating PD and related inflammatory systemic conditions such as diabetes, hypertension, and obesity. This review discusses the anti-inflammatory effects of A. muciniphila, its impact on periodontal health, and its potential role in managing systemic diseases. The overall aim is to elucidate how this bacterium might help reduce inflammation, improve oral health, and influence broader health outcomes.

Anaerobic bacteria dominate the cholesteatoma tissue of chronic suppurative otitis media patients

The aim of this study was to investigate both the microbial composition and absolute abundance of clinically relevant bacteria in tissue specimens from patients with chronic suppurative otitis media with cholesteatoma (CSOM with cholesteatoma). Mastoid mucosa and cholesteatoma tissue from eleven subjects with CSOM with cholesteatoma, and mastoid mucosa from ten controls were examined using standard hospital culture swabs, Gram staining, bacterial 16S rRNA gene sequencing, Droplet Digital PCR (ddPCR), and multiplex PCR. Positive results from culture swabs were reported in half the CSOM with cholesteatoma samples and 1 control sample. In contrast, ddPCR detected bacterial genes copies in all 11 mucosa and cholesteatoma of CSOM subjects and 3 control samples. The average bacterial gene copies in tissue samples with CSOM with cholesteaotoma (1.6 ± 0.7 log10) was significantly higher compared to healthy controls (0.3 ± 1.6). These results were corroborated with Gram-staining that identified the large presence of Gram-positive cocci cells in the cholesteatoma tissue of CSOM subjects which were not seen in the mucosa of controls. The most abundant genus detected by sequencing in the mucosa and cholesteatoma of CSOM samples was Anaerococcus (93.5% of all reads), and genus Meiothermus (0.9%) in the control sample. The 3 samples with the highest sequencing reads (>300) were further analysed using multiplex PCR to identify the dominant Anaerococcus species. Anaerococcus hydrogenalis was the dominant species identified in these samples. In contract, commonly named ear pathogens, genera Staphylococcus and Pseudomonas, were detected in low numbers (<0.001% of all sequencing reads) and low prevalence (2/16 samples) in the tissue samples of this study.The results show that culture severely underestimated the bacterial diversity in CSOM samples and investigating tissue rather than standard culture swabs might be advantageous to understanding the disease process. The high abundance of bacteria and the large presence of Gram-positive cells detected in the cholesteatoma tissue of CSOM compared to mucosa of CSOM or controls could be members from the genus Anaerococcus. Anaerococcus may well be a pathogen in CSOM with cholesteatoma, but their role in this condition requires further investigation.

Insights into the individual and combined effects of Cu(Ⅱ) and Ni(Ⅱ) on anammox: Nitrogen removal performance, enzyme activity and microbial community

Anaerobic ammonium oxidation (anammox) is an efficient and economical nitrogen removal process for treating ammonium-rich industrial wastewaters. However, Cu(Ⅱ) and Ni(Ⅱ) present in industrial wastewaters are toxic to anaerobic ammonium-oxidizing bacteria (AnAOB). Unfortunately, the effects of Cu(Ⅱ) and Ni(Ⅱ) on anammox have not been thoroughly investigated, especially when Cu(Ⅱ) and Ni(Ⅱ) coexist. This work comprehensively investigated the individual and combined effects of Cu(Ⅱ) and Ni(Ⅱ) on anammox and revealed the inhibitory mechanisms. With the influent NH4+-N and NO2−-N concentration of 230 and 250 mg L−1, the inhibition thresholds on anammox are 2.00 mg L−1 Cu(Ⅱ), 1.00 mg L−1 Ni(Ⅱ) and 1.00 mg L−1 Cu(Ⅱ) + 1.00 mg L−1 Ni(Ⅱ), and higher Cu(Ⅱ) or Ni(Ⅱ) concentrations resulted in sharp deteriorations of nitrogen removal performance. The inhibition of Ni(Ⅱ) on anammox was mainly attributed to the adverse effect on NiR activity, while the inhibition mechanism of Cu(Ⅱ) seemed to be unrelated to the four functional enzymes, but associated with disruption of cellular and organellar membranes. The behavior of extracellular polymeric substances (EPS) contributed to the antagonistic effect between Cu(Ⅱ) and Ni(Ⅱ) on anammox. In addition, the niche of Candidatus Brocadia and Candidatus Jettenia shifted under the Cu(II) and Ni(II) stress, and Candidatus Jettenia displayed greater tolerance to Cu(II) and Ni(II) stress. In conclusion, this research clarified the combined effect and the inhibitory mechanism of multiple heavy metals on anammox, and provide the guidances for anammox process application in treating high-ammonium industrial wastewaters containing heavy metals.

Veillonella parvula as an anaerobic lactate-fermenting bacterium for inhibition of tumor growth and metastasis through tumor-specific colonization and decrease of tumor’s lactate level

High tumor’s lactate level directly associates with high tumor growth, metastasis, and patients’ poor prognosis. Therefore, many studies have focused on the decrease of tumor’s lactate as a novel cancer treatment. In the present study for the first time, a strictly anaerobic lactate-fermenting bacterium, Veillonella parvula, was employed for the decrease of tumor’s lactate level. At first, 4T1 breast tumor-bearing BALB/c mice were administered with 106V. parvula bacteria intravenously, orally, intraperitoneally, and intratumorally. Then, the bacteria biodistribution was evaluated. The best administration route according to tumor colonization was selected and its safety was assessed. Then, the therapeutic effect of V. parvula administration through the best route was investigated according to 4T1 murine breast tumor’s growth and metastasis in vivo. In addition, histopathological and immunohistochemistry evaluations were done to estimate microscopic changes at the inner of the tumor and tumor’s lactate level was measured after V. parvula administration. V. parvula exhibited considerable tumor-targeting and colonization efficacy, 24 h after intravenous administration. Normal organs were free of the bacteria after 72 h and no side effect was observed. Tumor colonization by V. parvula significantly decreased the tumors’ lactate level for about 46% in comparison with control tumors which caused 44.3% and 51.6% decline (P < 0.05) in the mean tumors’ volume and liver metastasis of the treatment group in comparison with the control group, respectively. The treatment group exhibited 35% inhibition in the cancer cell proliferation in comparison with the control according to the Ki-67 immunohistochemistry staining. Therefore, intravenous administration of V. parvula is a tumor-specific and safe treatment which can significantly inhibit tumors’ growth and metastasis by decreasing the tumor lactate level.

Identification of a chlorosalicylic acid decarboxylase (CsaD) involved in decarboxylation of 3,6-DCSA from an anaerobic dicamba-degrading sludge.

3,6-Dichlorosalicylic acid (3,6-DCSA) is the demethylation metabolite of herbicide 3,6-dichloro-2-methoxy benzoic acid (dicamba). Previous studies have shown that anaerobic sludge further transformed 3,6-DCSA through decarboxylation and dechlorination. However, the anaerobe, enzyme, and gene involved in the anaerobic degradation of 3,6-DCSA are still unknown. In this study, an anaerobic sludge that efficiently degraded dicamba was enriched, and a 3,6-DCSA decarboxylase, designated chlorosalicylic acid decarboxylase (CsaD), was partially purified and identified from the anaerobic sludge. Metagenomic analysis showed that the csaD gene was located in a gene cluster of metagenome-assembled genome 8 (MAG8). MAG8 belonged to an uncultured order, OPB41, in the class Coriobacteriia of the phylum Actinobacteria, and its abundance increased approximately once during the enrichment process. CsaD was a non-oxidative decarboxylase in the amidohydrolase 2 family catalyzing the decarboxylation of 3,6-DCSA and 6-chlorosalicylic acid (6-CSA). Its affinity and catalytic efficiency for 3,6-DCSA were significantly higher than those for 6-CSA. This study provides new insights into the anaerobic catabolism of herbicide dicamba.IMPORTANCEDicamba, an important hormone herbicide, easily migrates to anoxic habitats such as sediment, ground water, and deep soil. Thus, the anaerobic catabolism of dicamba is of importance. Anaerobic bacteria or sludge demethylated dicamba to 3,6-DCSA, and in a previous study, based on metabolite identification, it was proposed that 3,6-DCSA be further degraded via two pathways: decarboxylation to 2,5-dichlorophenol, then dechlorination to 3-chlorophenol (3-CP); or dechlorination to 6-CSA, then decarboxylation to 3-CP. However, there was no physiological and genetic validation for the pathway. In this study, CsaD catalyzed the decarboxylation of both 3,6-DCSA and 6-CSA, providing enzyme-level evidence for the anaerobic catabolism of 3,6-DCSA through the two pathways. CsaD was located in MAG8, which belonged to an uncultured anaerobic actinomycetes order, OPB41, indicating that anaerobic actinomycetes in OPB41 was involved in the decarboxylation of 3,6-DCSA. This study provides a basis for understanding the anaerobic catabolism of dicamba and the demethylation product, 3,6-DCSA.

Associations between gut microbiota and osteoporosis or osteopenia in a cohort of Chinese Han youth

Osteoporosis (OP) is a common metabolic bone disease characterized by low bone mass and microstructural deterioration of bone. Changes in the composition and structure of gut microbiota (GM) are related to changes of bone mass and bone microstructure. However, the relationship between GM and bone mineral density (BMD) is complex, and data are especially scarce for Chinese Han youth. Therefore, 62 Chinese Han youth participants were recruited. Furthermore, according to the T–score evaluation criteria of the World Health Organization (WHO), we divided the BMD levels of participants into three groups: osteoporosis\\BDL, osteopenia\\BDM, normal bone density\\BDH, and the associations between GM community and BMD groups were conducted. According to alpha and beta diversity analysis, significant differences were found in the microbial richness and composition between groups. The dominant phyla of GM in a cohort of Chinese Han youth were Bacteroidota (50.6%) and Firmicutes (41.6%). Anaerobic microorganisms, such as g_Faecalibacterium and g_Megamonas, account for the largest proportion in the gut, which were mainly Firmicutes phylum. The dominant genera and species in the three BMD groups were g_Prevotella, g_Bacteroides, g_Faecalibacterium, g_Megamonas, s_Prevotella copri, s_unclassified_g_Faecalibacterium, s_unclassified_g_Prevotella, s_unclassified_g_Bacteroides and s_Bacteroides plebeius. g_Faecalibacterium, g_Bacteroides and g_Ruminococcus differed between the BDH and BDL groups as well as between the BDH and BDM groups. LEfSe showed three genus communities and eight species communities were enriched in the three BMD groups, respectively. The associations between microbial relative abundance and T–score was not statistically significant by Spearman and regression analysis. In conclusion, the alpha diversity indexes in the BDH group were higher than in the BDL group, and several taxa were identified that may be the targets for diagnosis and therapy of OP.

Dynamic response of the intestinal microbiome to Eimeria maxima-induced coccidiosis in chickens.

We have observed for the first time the dynamic response of the intestinal microbiota to Eimeria maxima infection, synchronized with its life cycle. Minimal changes occur in both the ileal and cecal microbiota during early infection, while significant alterations coincide with acute infection and disruption of the intestinal mucosal lining. As animals recover from coccidiosis, the intestinal microbiota largely returns to normal. E. maxima-induced intestinal inflammation likely creates an environment conducive to the growth of aerotolerant anaerobes such as Lactobacillus, as well as facultative anaerobes such as Escherichia, Enterococcus, and Staphylococcus, while suppressing the growth of obligate anaerobes such as short-chain fatty acid-producing bacteria. These findings expand our understanding of the temporal dynamics of the microbiota structure during Eimeria infection and offer insights into the pathogenesis of coccidiosis, supporting the rationale for microbiome-based strategies in the control and prevention of this condition.

Unveiling wheat growth promotion potential of phosphate solubilizing Pantoea agglomerans PS1 and PS2 through genomic, physiological, and metagenomic characterizations.

Phosphorus is an abundant element in the earth's crust and is generally found as complex insoluble conjugates. Plants cannot assimilate insoluble phosphorus and require external supplementation as chemical fertilizers to achieve a good yield. Continuous use of fertilizers has impacted soil ecology, and a sustainable solution is needed to meet plant elemental requirements. Phosphate solubilizing microbes could enhance phosphorus bioavailability for better crop production and can be employed to attain sustainable agriculture practices. The current study unveils the biofertilizer potential of wheat rhizospheric bacteria through physiological, taxonomic, genomic, and microbiomics experimentations. Culture-dependent exploration identified phosphate-solubilizing PS1 and PS2 strains from the wheat rhizosphere. These isolates were rod-shaped, gram-negative, facultative anaerobic bacteria, having optimum growth at 37°C and pH 7. Phylogenetic and phylogenomic characterization revealed their taxonomic affiliation as Pantoea agglomerans subspecies PS1 & PS2. Both isolates exhibited good tolerance against saline (>10% NaCl (w/v), >11.0% KCl (w/v), and >6.0% LiCl (w/v)), oxidizing (>5.9% H2O2 (v/v)) conditions. PS1 and PS2 genomes harbor gene clusters for biofertilization features, root colonization, and stress tolerance. PS1 and PS2 showed nitrate reduction, phosphate solubilization, auxin production, and carbohydrate utilization properties. Treatment of seeds with PS1 and PS2 significantly enhanced seed germination percentage (p = 0.028 and p = 0.008, respectively), number of tillers (p = 0.0018), number of leaves (p = 0.0001), number of spikes (p = 0.0001) and grain production (p = 0.0001). Wheat rhizosphere microbiota characterizations indicated stable colonization of PS1 and PS2 strains in treated seeds at different feek stages. Pretreatment of seeds with both strains engineered the wheat rhizosphere microbiota by recruiting plant growth-promoting microbial groups. In vitro, In vivo, and microbiota characterization studies indicated the biofertilizer potential of Pantoea sp. PS1 & PS2 to enhance wheat crop production. The employment of these strains could fulfill plant nutrient requirements and be a substitute for chemical fertilizers for sustainable agriculture.

Full-length structure and heme binding in the transcriptional regulator HcpR.

HcpR is a CRP-family transcriptional regulator found in many Gram-negative anaerobic bacteria. In the perio-pathogen Porphyromonas gingivalis, HcpR is crucial for the response to reactive nitrogen species such as nitric oxide (NO). Binding of NO to the heme group of HcpR leads to transcription of the redox enzyme Hcp. However, the molecular mechanisms of heme binding to HcpR remain unknown. In this study we present the 2.3Å structure of the P. gingivalis HcpR. Interdomain interactions present in the structure help to form a hydrophobic pocket in the N-terminal sensing domain. A comparison analysis with other CRP-family members reveals that the molecular mechanisms of HcpR-mediated regulation may be distinct from other family members. Using docking studies, we identify a putative heme binding site in the sensing domain. In vitro complementation and mutagenesis studies verify Met68 as an important residue in activation of HcpR. Finally, heme binding studies with purified forms of recombinant HcpR support Met68 and His149 residues as important for proper heme coordination in HcpR.

A Case of Raoultella Ornithinolytica Cholangitis in A Liver Transplant Recipient.

We present the first documented case of Raoultella ornithinolytica bacteraemia in a patient with liver transplantation. R. ornithinolytica is a Gram-negative anaerobic bacterium found in aquatic environments in fish and birds, and is source of nosocomial infection causing pneumonia, enteritis, cholangitis or urinary infections, associated with surgical interventions in a hospital setting. A 44-year-old female presented with a 2-day history of fever, rigors, and headache. Her past medical history was significant for having received three orthotopic liver transplants due to Wilson's disease over a 20-year period. Her physical examination was unremarkable besides stigmata of prior liver transplantation. Blood tests revealed mild elevations in liver function markers and raised inflammatory markers. R. ornithinolytica was eventually isolated from blood cultures. Subsequent magnetic resonance cholangiopancreatography (MRCP) demonstrated new left intrahepatic ductal dilation with heterogeneous peripheral enhancement. The proximal location of the cholangitis explained the lack of abdominal pain or tenderness. The patient was treated with appropriate antibiotic therapy and cultures were negative on day 2. The patient recovered without further intervention. Seldom encountered R. ornithinolytica is uncommonly pathogenic but should be considered in patients receiving immunosuppressants and those with complex surgical anatomy. This is the first case of Raoultella cholangitis in a liver transplant recipient described in the literature.Atypical clinical presentation and atypical infections are common in this patient group.Cholangitis should be suspected in all liver transplant recipients due to immunosuppression.

Lemierre’s Syndrome – Case Report of a 20-Year-Old Male with Post-Anginal Sepsis

&lt;b&gt;Introduction:&lt;/b&gt; Lemierre’s syndrome, first described by André Lemierre in 1936, is a rare but life-threatening condition. It is characterized by a triad of symptoms: pharyngeal infection, internal jugular vein thrombosis, and sepsis with distant abscesses, usually in the lungs. The primary pathogen is the anaerobic Gram-negative bacterium &lt;i&gt;Fusobacterium necrophorum&lt;/i&gt; (&lt;i&gt;F. necrophorum&lt;/i&gt;). In recent years, there has been an increase in the incidence of Lemierre’s syndrome.&lt;b&gt;Case report:&lt;/b&gt; A 20-year-old male was admitted to the Emergency Department (ED) with jaundice, dyspnea, sore throat, fever up to 39C, neck pain, and left lower limb weakness. Examination revealed enlarged palatine tonsils with purulent exudates and a right-sided peritonsillar abscess. Laboratory tests showed elevated inflammatory markers, thrombocytopenia, and leukocytosis. Computed topography (CT) confirmed internal jugular vein thrombosis, abscesses in the right sternocleidomastoid muscle, and bilateral pleural effusions. The patient received oxygen therapy, antibiotics, anticoagulation, and pleural drainage. After 26 days of hospitalization, he was discharged with a recommendation to continue antibiotic therapy and low-molecular-weight heparin, as well as planned removal of the palatine tonsils (tonsillectomy).&lt;b&gt;Discussion:&lt;/b&gt; Lemierre’s syndrome is a severe complication of upper respiratory tract infections, mainly affecting young individuals. Symptoms include pharyngeal infection, sepsis, and internal jugular vein thrombosis. Early diagnosis and appropriate treatment, including prolonged antibiotics and sometimes anticoagulation, are crucial. The rise in incidence may be linked to the irrational use of antibiotics. Educating clinicians is vital to improve outcomes and reduce complications.&lt;b&gt;Conclusions:&lt;/b&gt; Initial symptoms of Lemierre’s syndrome are nonspecific, complicating early diagnosis. Neck imaging and/or positive blood cultures are key for diagnosis. The incidence is 1–2.5 cases per million annually, making it rare but potentially fatal. Mortality before antibiotics was around 90%; currently, it is 5–18%, but higher without proper diagnosis. Early imaging significantly improves prognosis.

Vaginal microbiota, menopause, and the use of menopausal hormone therapy: a cross-sectional, pilot study in Chinese women.

To compare the vaginal microbiota of premenopausal and postmenopausal women and postmenopausal women undergoing menopausal hormone therapy (MHT) and examine the association between vaginal microbiota and genitourinary syndrome of menopause (GSM). This cross-sectional study classified 94 women aged 40 to 60 years into three groups: premenopausal (Pre, n = 32), postmenopausal (Post, n = 30), and postmenopausal women who received MHT orally (Post + MHT, n = 32). Neither the Pre nor the Post group received hormone therapy within the past 6 months. Postmenopausal women who received vaginal MHT were not included. Vaginal swabs were obtained, and microbial composition was characterized by 16S rRNA gene sequencing targeting the V3 to V4 region. Clinical data were collected and serum sex hormones were measured. The most bothersome symptom approach and vaginal health index were used to evaluate GSM. Mann-Whitney U or Kruskal-Wallis ANOVA followed by multiple comparison tests were performed for comparison between or across groups. The correlations between GSM symptom scores and vaginal microbiota were determined using Spearman's correlation analysis. The vaginal community of postmenopausal women was characterized by a decreased abundance of Lactobacillus (Post 18% vs Pre 69%); an increased abundance of several anaerobic bacteria, including Prevotella, Escherichia-Shigella, and Bifidobacterium; and a higher microbial diversity (P < 0.001 for Shannon and Simpson indexes) than those of premenopausal women. The vaginal community of postmenopausal women who received MHT had an increased abundance of Lactobacillus (54%) and lower microbial diversity (P < 0.001 for Shannon and Simpson indexes) than the postmenopausal women. The vaginal microbial community composition of the Pre group shared more similarity with that of the Post + MHT group (Adonis P = 0.051) than with that of the Post group (Adonis P < 0.001). A decreased abundance of Lactobacillus and high diversity in the vaginal community were found in women with moderate to severe GSM symptoms. Among Chinese postmenopausal women, those receiving MHT had higher Lactobacillus abundance but lower abundance of diverse anaerobes and diversity of the vaginal microbial community compared to non-MHT women. MHT in postmenopausal women may potentially contribute to reestablishing vaginal microbiota homeostasis. Findings in this pilot study, however, need to be examined in larger, prospective studies.