Oral bacteria accelerate pancreatic cancer development in mice.

OBJECTIVE: Epidemiological studies highlight an association between pancreatic ductal adenocarcinoma (PDAC) and oral carriage of the anaerobic bacterium Porphyromonas gingivalis, a species highly linked to periodontal disease. We analysed the potential for P. gingivalis to promote pancreatic cancer development in an animal model and probed underlying mechanisms. DESIGN: We tracked P. gingivalis bacterial translocation from the oral cavity to the pancreas following administration to mice. To dissect the role of P. gingivalis in PDAC development, we administered bacteria to a genetically engineered mouse PDAC model consisting of inducible acinar cell expression of mutant Kras (Kras +/LSL-G12D; Ptf1a-CreER, iKC mice). These mice were used to study the cooperative effects of Kras mutation and P. gingivalis on the progression of pancreatic intraepithelial neoplasia (PanIN) to PDAC. The direct effects of P. gingivalis on acinar cells and PDAC cell lines were studied in vitro. RESULTS: P. gingivalis migrated from the oral cavity to the pancreas in mice and can be detected in human PanIN lesions. Repetitive P. gingivalis administration to wild-type mice induced pancreatic acinar-to-ductal metaplasia (ADM), and altered the composition of the intrapancreatic microbiome. In iKC mice, P. gingivalis accelerated PanIN to PDAC progression. In vitro, P. gingivalis infection induced acinar cell ADM markers SOX9 and CK19, and intracellular bacteria protected PDAC cells from reactive oxygen species-mediated cell death resulting from nutrient stress. CONCLUSION: Taken together, our findings demonstrate a causal role for P. gingivalis in pancreatic cancer development in mice.

Combined pH ratiometry and fluorescence lectin-binding analysis (pH-FLBA) for microscopy-based analyses of biofilm pH and matrix carbohydrates.

Bacterial biofilms have a complex and heterogeneous three-dimensional architecture that is characterized by chemically and structurally distinct microenvironments. Confocal microscopy-based pH ratiometry and fluorescence lectin-binding analysis (FLBA) are well-established methods to characterize pH developments and the carbohydrate matrix architecture of biofilms at the microscale. Here, we developed a combined analysis, pH-FLBA, to concomitantly map biofilm pH and the distribution of matrix carbohydrates in bacterial biofilms while preserving the biofilm microarchitecture. As a proof of principle, the relationship between pH and the presence of galactose- and fucose-containing matrix components was investigated in dental biofilms grown with and without sucrose. The pH response to a sucrose challenge was monitored in different areas at the biofilm base using the ratiometric pH-sensitive dye C-SNARF-4. Thereafter, the fucose- and galactose-specific fluorescently labeled lectins Aleuria aurantia lectin (AAL) and Morus nigra agglutinin G (MNA-G) were used to visualize carbohydrate matrix components in the same biofilm areas and their immediate surroundings. Sucrose during growth significantly decreased biofilm pH (P < 0.05) and increased the amounts of both MNA-G- and AAL-targeted matrix carbohydrates (P < 0.05). Moreover, it modulated the biofilm composition towards a less diverse community dominated by streptococci, as determined by 16S rRNA gene sequencing. Altogether, these results suggest that the production of galactose- and fucose-containing matrix carbohydrates is related to streptococcal metabolism and, thereby, pH profiles in dental biofilms. In conclusion, pH-FLBA using lectins with different carbohydrate specificities is a useful method to investigate the association between biofilm pH and the complex carbohydrate architecture of bacterial biofilms.IMPORTANCEBiofilm pH is a key regulating factor in several biological and biochemical processes in environmental, industrial, and medical biofilms. At the microscale, microbial biofilms are characterized by steep pH gradients and an extracellular matrix rich in carbohydrate components with diffusion-modifying properties that contribute to bacterial acid-base metabolism. Here, we propose a combined analysis of pH ratiometry and fluorescence lectin-binding analysis, pH-FLBA, to concomitantly investigate the matrix architecture and pH developments in microbial biofilms, using complex saliva-derived biofilms as an example. Spatiotemporal changes in biofilm pH are monitored non-invasively over time by pH ratiometry, while FLBA with lectins of different carbohydrate specificities allows mapping the distribution of multiple relevant matrix components in the same biofilm areas. As the biofilm structure is preserved, pH-FLBA can be used to investigate the in situ relationship between the biofilm matrix architecture and biofilm pH in complex multispecies biofilms.

Mediation of Bacterial Interactions via a Novel Membrane-Based Segregator to Enhance Biological Nitrogen Removal.

The regulation of microbial subpopulations in wastewater treatment plants (WWTPs) with desired functions can guarantee nutrient removal. In nature, "good fences make good neighbors," which can be applied to engineering microbial consortia. Herein, a membrane-based segregator (MBSR) was proposed, where porous membranes not only promote the diffusion of metabolic products but also isolate incompatible microbes. The MBSR was integrated with an anoxic/aerobic membrane bioreactor (i.e., an experimental MBR). The long-term operation showed that the experimental MBR exhibited higher nitrogen removal (10.45 ± 2.73 mg/L total nitrogen) than the control MBR (21.68 ± 4.23 mg/L) in the effluent. The MBSR resulted in much lower oxygen reduction potential in the anoxic tank of the experimental MBR (-82.00 mV) compared to that of the control MBR (83.25 mV). The lower oxygen reduction potential can inevitably aid in the occurrence of denitrification. The 16S rRNA sequencing showed that the MBSR significantly enriched acidogenic consortia, which yielded considerable volatile fatty acids by fermenting the added carbon sources and allowed efficient transfer of these small molecules to the denitrifying community. Moreover, the sludge communities of the experimental MBR harbored a higher abundance of denitrifying bacteria than those of the control MBR. Metagenomic analysis further corroborated these sequencing results. The spatially structured microbial communities in the experimental MBR system demonstrate the practicability of the MBSR, achieving nitrogen removal efficiency superior to that of mixed populations. Our study provides an engineering method for modulating the assembly and metabolic division of labor of subpopulations in WWTPs. IMPORTANCE This study provides an innovative and applicable method for regulating subpopulations (activated sludge and acidogenic consortia), which contributes to the precise control of the metabolic division of labor in biological wastewater treatment processes.

Effects of Dietary Nonfibrous Carbohydrate/Neutral Detergent Fiber Ratio on Methanogenic Archaea and Cellulose-Degrading Bacteria in the Rumen of Karakul Sheep: a 16S rRNA Gene Sequencing Study.

The study was conducted to investigate the effects of dietary nonfibrous carbohydrate (NFC)/neutral detergent fiber (NDF) ratio on methanogenic archaea and cellulose-degrading bacteria in Karakul sheep by 16S rRNA gene sequencing. Twelve Karakul sheep were randomly divided into four groups, each group with three replicates, and they were fed with four dietary NFC/NDF ratios at 0.54, 0.96, 1.37, and 1.90 as groups 1, 2, 3, and 4, respectively. The experiment lasted for four periods: I (1 to 18 days), II (19 to 36 days), III (37 to 54 days), and IV (55 to 72 days); during each period, rumen contents were collected before morning feeding to investigate on methanogenic archaea and cellulose-degrading bacteria. The results showed that with an increase in dietary NFC/NDF ratio, the number of rumen archaea operational taxonomic units and the diversity of archaea decrease. The most dominant methanogens did not change with dietary NFC/NDF ratio and prolongation of experimental periods. Methanobrevibacter was the most dominant genus. At the species level, the relative abundance of Methanobrevibacter ruminantium first increased and then decreased when the NFC/NDF ratio increased. When the dietary NFC/NDF ratio was 0.96, the structure of archaea was largely changed, and the relative abundance of Fibrobacter sp. strain UWCM, Ruminococcus flavefaciens, and Ruminococcus albus were the highest. When the dietary NFC/NDF ratio was 1.37, the relative abundance of Butyrivibrio fibrisolvens was higher than for other groups. Based on all the data, we concluded that a dietary NFC/NDF ratio of ca. 0.96 to 1.37 was a suitable ratio to support optimal sheep production. IMPORTANCE CH4 produced by ruminants aggravates the greenhouse effect and cause wastage of feed energy, and CH4 emissions are related to methanogens. According to the current literature, there is a symbiotic relationship between methanogens and cellulolytic bacteria, so reducing methane will inevitably affect the degradation of fiber materials. This experiment used 16S rRNA gene high-throughput sequencing technology to explore the balance relationship between methanogens and cellulolytic bacteria for the first time through a long-term feeding period. The findings provide fundamental data, supporting for the diet structures with potential to reduce CH4 emission.

Tween-80 enhanced biodegradation of naphthalene by Klebsiella quasipneumoniae.

Accidental spillage of petroleum products and industrial activities result in various hydrocarbons in the environment. While the n-hydrocarbons are readily degraded, the polycyclic aromatic hydrocarbons (PAHs) are recalcitrant to natural degradation, toxic to aquatic life and are responsible for diverse health challenges in terrestrial animals; suggesting the need for faster and more eco-friendly ways of removing PAHs from the environment. In this study, the surfactant tween-80 was used to enhance a bacterium's intrinsic naphthalene biodegradation activity. Eight bacteria isolated from oil-contaminated soils were characterised using morphological and biochemical methods. The most effective strain was identified as Klebsiella quasipneumoniae using 16S rRNA gene analysis. High-Performance Liquid Chromatography (HPLC) analyses showed that the detectable concentration of naphthalene was decreased from 500 to 157.18 µg/mL (67.4%) after 7 d in the absence of tween-80, while 99.4% removal was achieved in 3 d in the presence of tween-80 at 60 µg/mL concentration. The peaks observed in the Fourier Transform Infra-Red Spectroscopy (FTIR) spectrum of control (naphthalene), which were absent in that of the metabolites, further established naphthalene degradation. Furthermore, Gas Chromatography-Mass Spectrometer (GCMS) revealed metabolites of single aromatic ring, such as 3,4-dihydroxybenzoic acid 4-hydroxylmethylphenol, which confirmed that the removal of naphthalene is by biodegradation. Tyrosinase induction and laccase activities suggested the involvement of these enzymes in naphthalene biodegradation by the bacterium. Conclusively, a strain of K. quasipneumoniae that can effectively remove naphthalene from contaminated environments has been isolated, and its biodegradation rate was doubled in the presence of non-ionic surfactant, tween-80.

Combined exposure to polyvinyl chloride and polystyrene microplastics induces liver injury and perturbs gut microbial and serum metabolic homeostasis in mice.

A variety of microplastics (MPs) have become ubiquitous environmental pollutants, leading to inevitable human contact and health impacts. Most previous research has explored the toxic effects of a single type of MPs exposure. However, the effects of co-exposure to both common types of MPs, polyvinyl chloride (PVC) and polystyrene (PS) MPs on mammals have not been explored. Here, adult mice were exposed to PS-PVC (1.0 µm PS and 2.0 µm PVC both at the concentration of 0.5 mg/day) for 60 days. The results showed that PS-PVC co-exposure-induced hepatotoxicity was evidenced by liver histopathological changes, the release of inflammatory cytokines, and the activation of oxidative stress. Moreover, the intestinal mucosal barrier was damaged after PS-PVC treatment. The results of 16S rRNA gene sequencing reported there was a marked shift in the gut microbial structure accompanied by decreased relative abundances of probiotics, such as Clostridium, Lachnospiraceae_UCG-006, Desulfovibrio, Clostridiales_unclassified and Ruminococcaceae_unclassified and increased the conditional pathogen abundances, such as Erysipelatoclostridium. Furthermore, the triglyceride (TG) and total cholesterol (TCH) expression levels in the serum and liver were increased after PS-PVC co-exposure. Serum metabolomics analysis showed that there were 717 differential expression metabolites found in the positive- and negative-ion modes, including 476 up-regulated and 241 down-regulated, mainly enriched in butyrate metabolism, thiamine metabolism, and phenylacetate metabolism. In addition, remarked changes in the gut microbiota and serum metabolic profiles were closely related to hepatic and intestinal injuries after PS-PVC co-exposure. These results have provided new insights into the toxic effects of PS and PVC MPs co-exposure through the gut-liver axis and the health risks of PS and PVC MPs should be paid more attention to humans.

Participants in the Trans-Antarctic Winter Traverse Expedition Showed Increased Bacterial Load and Diversity in Saliva but Maintained Individual Differences within Stool Microbiota and Across Metabolite Fingerprints.

Understanding the impact of long-term physiological and environmental stress on the human microbiota and metabolome may be important for the success of space flight. This work is logistically difficult and has a limited number of available participants. Terrestrial analogies present important opportunities to understand changes in the microbiota and metabolome and how this may impact participant health and fitness. Here, we present work from one such analogy: the Transarctic Winter Traverse expedition, which we believe is the first assessment of the microbiota and metabolome from different bodily locations during prolonged environmental and physiological stress. Bacterial load and diversity were significantly higher during the expedition when compared with baseline levels (p < 0.001) in saliva but not stool, and only a single operational taxonomic unit assigned to the Ruminococcaceae family shows significantly altered levels in stool (p < 0.001). Metabolite fingerprints show the maintenance of individual differences across saliva, stool, and plasma samples when analysed using flow infusion electrospray mass spectrometry and Fourier transform infrared spectroscopy. Significant activity-associated changes in terms of both bacterial diversity and load are seen in saliva but not in stool, and participant differences in metabolite fingerprints persist across all three sample types.

Evaluation of the Oral Bacterial Genome and Metabolites in Patients with Wolfram Syndrome.

In Wolfram syndrome (WFS), due to the loss of wolframin function, there is increased ER stress and, as a result, progressive neurodegenerative disorders, accompanied by insulin-dependent diabetes. The aim of the study was to evaluate the oral microbiome and metabolome in WFS patients compared with patients with type 1 diabetes mellitus (T1DM) and controls. The buccal and gingival samples were collected from 12 WFS patients, 29 HbA1c-matched T1DM patients (p = 0.23), and 17 healthy individuals matched by age (p = 0.09) and gender (p = 0.91). The abundance of oral microbiota components was obtained by Illumina sequencing the 16S rRNA gene, and metabolite levels were measured by gas chromatography-mass spectrometry. Streptococcus (22.2%), Veillonella (12.1%), and Haemophilus (10.8%) were the most common bacteria in the WFS patients, while comparisons between groups showed significantly higher abundance of Olsenella, Dialister, Staphylococcus, Campylobacter, and Actinomyces in the WFS group (p < 0.001). An ROC curve (AUC = 0.861) was constructed for the three metabolites that best discriminated WFS from T1DM and controls (acetic acid, benzoic acid, and lactic acid). Selected oral microorganisms and metabolites that distinguish WFS patients from T1DM patients and healthy individuals may suggest their possible role in modulating neurodegeneration and serve as potential biomarkers and indicators of future therapeutic strategies.

Micrococcus luteus strain CGK112 isolated from cow dung demonstrated efficient biofilm-forming ability and degradation potential toward high-density polyethylene (HDPE).

Biodegradation is the most promising environmentally sustainable method that offers a significant opportunity with minimal negative environmental consequences while searching for solutions to this global problem of plastic pollution that has now spread to almost everywhere in the entire world. In the present work, HDPE-degrading bacterial strain CGK112 was isolated from the fecal matter of a cow. The bacterial strain was identified as Micrococcus luteus CGK112 by 16S rRNA sequence coding analysis. Significant weight loss, i.e., 3.85% was recorded in the HDPE film treated with strain CGK112 for 90 days. The surface micromorphology was examined using FE-SEM, which revealed spectacular bacterial colonization as well as structural deformation. Furthermore, the EDX study indicated a significant decrease in the atomic percentage of carbon content, whereas FTIR analysis confirmed functional groups alternation as well as an increase in the carbonyl index which can be attributed to the metabolic activity of biofilm. Our findings provide insight into the capacity of our strain CGK112 to colonize and utilize HDPE as a single carbon source, thus promoting its degradation.

Investigation of microplastic accumulation in Rastrelliger kanagurta fish gut and microplastic degradation behaviour of existing gut bacteria Pseudomonas sp.

Microplastic is a minute particle of chemical pollutant in marine environment and classified as less than 5 mm size. The microplastics could not degrade for long years and they are ingested, incorporated, and accumulated in tissues of living organisms, particularly can cause various ecotoxicological effects for their behavioural change, cytotoxicity, neuro-toxicity effects, liver stress, etc. This preliminary study was investigated the abundance and accumulation of microplastic in marine fish of Indian mackerel (Rastrelliger kanagurta) gut region. Further, we identified the microplastic through stereomicroscope in Indian mackerel fish size up to 0.02 mm. In FT-IR analysis were identified the chemical group which were represents as nylon. In GC-MS analysis were identified that hexa decanoic acid and methyl ester plastic compounds as well as identify and screened the microplastic degrading bacteria from fish gut through partial 16S rRNA gene sequencing analysis it was shows that the isolate reveals a Pseudomonas sp. As a result, it is possible that gut bacteria have a probiotic role in fish gut to may degrade microplastics.

Biological cellulose saccharification using a coculture of Clostridium thermocellum and Thermobrachium celere strain A9.

An anaerobic thermophilic bacterial strain, A9 (NITE P-03545), that secretes ß-glucosidase was newly isolated from wastewater sediments by screening using esculin. The 16S rRNA gene sequence of strain A9 had 100% identity with that of Thermobrachium celere type strain JW/YL-NZ35. The complete genome sequence of strain A9 showed 98.4% average nucleotide identity with strain JW/YL-NZ35. However, strain A9 had different physiological properties from strain JW/YL-NZ35, which cannot secrete ß-glucosidases or grow on cellobiose as the sole carbon source. The key ß-glucosidase gene (TcBG1) of strain A9, which belongs to glycoside hydrolase family 1, was characterized. Recombinant ß-glucosidase (rTcBG1) hydrolyzed cellooligosaccharides to glucose effectively. Furthermore, rTcBG1 showed high thermostability (at 60°C for 2 days) and high glucose tolerance (IC50 = 0.75 M glucose), suggesting that rTcBG1 could be used for biological cellulose saccharification in cocultures with Clostridium thermocellum. High cellulose degradation was observed when strain A9 was cocultured with C. thermocellum in a medium containing 50 g/l crystalline cellulose, and glucose accumulation in the culture supernatant reached 35.2 g/l. In contrast, neither a monoculture of C. thermocellum nor coculture of C. thermocellum with strain JW/YL-NZ35 realized efficient cellulose degradation or high glucose accumulation. These results show that the ß-glucosidase secreted by strain A9 degrades cellulose effectively in combination with C. thermocellum cellulosomes and has the potential to be used in a new biological cellulose saccharification process that does not require supplementation with ß-glucosidases. KEY POINTS: • Strain A9 can secrete a thermostable ß-glucosidase that has high glucose tolerance • A coculture of strain A9 and C. thermocellum showed high cellulose degradation • Strain A9 achieves biological saccharification without addition of ß-glucosidase.

Lysobacter chinensis sp. nov., a cellulose-degrading strain isolated from cow dung compost.

A novel bacterial strain, TLK-CK17T, was isolated from cow dung compost sample. The strain was Gram-staining negative, non-gliding rods, aerobic, and displayed growth at 15-40 °C (optimally, 35 °C), with 0-5.0% (w/v) NaCl (optimally, 0.5) and at pH 6.5-8.5 (optimally, 7.0-7.5). The assembled genome of strain TLK-CK17T has a total length of 4.3 Mb with a G + C content of 68.2%. According to the genome analysis, strain TLK-CK17T encodes quite a few glycoside hydrolases that may play a role in the degradation of accumulated plant biomass in compost. On the basis 16S rRNA gene sequence analysis, strain TLK-CK17T showed the highest sequence similarity (98.9%) with L. penaei GDMCC 1.1817 T, followed by L. maris KCTC 42381 T (98.3%). Cells contained iso-C16:0, iso-C15:0, and summed feature 9 (comprising C17:1 ω9c and/or 10-methyl C16:0), as its major cellular fatty acids (> 10.0%) and ubiquinone-8 as the exclusively respiratory quinone. Diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol prevailed among phospholipids. Based on the phenotypic, genomic and phylogenetic data, strain TLK-CK17T represents a novel species of the genus Lysobacter, for which the name Lysobacter chinensis sp. nov. is proposed, and the type strain is TLK-CK17T (= CCTCC AB2021257T = KCTC 92122 T).

Shotgun Metagenomics Study Suggests Alteration in Sulfur Metabolism and Oxidative Stress in Children with Autism and Improvement after Microbiota Transfer Therapy.

Links between gut microbiota and autism spectrum disorder (ASD) have been explored in many studies using 16S rRNA gene amplicon and shotgun sequencing. Based on these links, microbiome therapies have been proposed to improve gastrointestinal (GI) and ASD symptoms in ASD individuals. Previously, our open-label microbiota transfer therapy (MTT) study provided insight into the changes in the gut microbial community of children with ASD after MTT and showed significant and long-term improvement in ASD and GI symptoms. Using samples from the same study, the objective of this work was to perform a deeper taxonomic and functional analysis applying shotgun metagenomic sequencing. Taxonomic analyses revealed that ASD Baseline had many bacteria at lower relative abundances, and their abundance increased after MTT. The relative abundance of fiber consuming and beneficial microbes including Prevotella (P. dentalis, P. enoeca, P. oris, P. meloninogenica), Bifidobacterium bifidum, and a sulfur reducer Desulfovibrio piger increased after MTT-10wks in children with ASD compared to Baseline (consistent at genus level with the previous 16S rRNA gene study). Metabolic pathway analysis at Baseline compared to typically developing (TD) children found an altered abundance of many functional genes but, after MTT, they became similar to TD or donors. Important functional genes that changed included: genes encoding enzymes involved in folate biosynthesis, sulfur metabolism and oxidative stress. These results show that MTT treatment not only changed the relative abundance of important genes involved in metabolic pathways, but also seemed to bring them to a similar level to the TD controls. However, at a two-year follow-up, the microbiota and microbial genes shifted into a new state, distinct from their levels at Baseline and distinct from the TD group. Our current findings suggest that microbes from MTT lead to initial improvement in the metabolic profile of children with ASD, and major additional changes at two years post-treatment. In the future, larger cohort studies, mechanistic in vitro experiments and metatranscriptomics studies are recommended to better understand the role of these specific microbes, functional gene expression, and metabolites relevant to ASD.

Effect and Mechanism of Pharmaceutical Excipients on Berberine to Alleviate Ulcerative Colitis via Regulating Gut Microbiota.

BACKGROUND: Various potential effect of drugs on alleviating diseases by regulating intestinal microbiome as well as the pharmaceutical excipients on gut microbiota has been revealed. However, the interaction between them is rarely investigated. METHODS: Histological analysis, immunohistochemistry analysis, enzyme-linked immunosorbent assay (ELISA) analysis, RT-qPCR, and 16S rRNA analysis were utilized to explore the effect mechanism of the five excipients including hydroxypropyl methylcellulose (HPMC) F4M, Eudragit (EU) S100, chitosan (CT), pectin (PT), and rheum officinale polysaccharide (DHP) on berberine (BBR) to cure UC. RESULTS: The combined BBR with PT and DHP group exhibited better therapeutic efficacy of UC with significantly increased colon length, and decreased hematoxylin-eosin (H&E) scores than other groups. Furthermore, the expression of tight junction ZO-1 and occludin in colon tissue were upregulated, and claudin-2 was downregulated. Ultimately, the serum content of tumor necrosis (TNF)-α, interleukin (IL)-1ß, and IL-6 was decreased. Moreover, the combined BBR with PT significantly promoted the restoration of gut microbiota. The relative abundance of Firmicutes and Lactobacillus was significantly increased by the supplement of PT and DHP, and the relative abundance of Proteobacteria was downregulated. CONCLUSIONS: Our study may provide a new perspective that the selection of pharmaceutical excipients could be a crucial factor affecting the drugs' therapeutic efficiency outcome.

Growth of sedimentary Bathyarchaeota on lignin as an energy source.

Members of the archaeal phylum Bathyarchaeota are among the most abundant microorganisms on Earth. Although versatile metabolic capabilities such as acetogenesis, methanogenesis, and fermentation have been suggested for bathyarchaeotal members, no direct confirmation of these metabolic functions has been achieved through growth of Bathyarchaeota in the laboratory. Here we demonstrate, on the basis of gene-copy numbers and probing of archaeal lipids, the growth of Bathyarchaeota subgroup Bathy-8 in enrichments of estuarine sediments with the biopolymer lignin. Other organic substrates (casein, oleic acid, cellulose, and phenol) did not significantly stimulate growth of Bathyarchaeota Meanwhile, putative bathyarchaeotal tetraether lipids incorporated 13C from 13C-bicarbonate only when added in concert with lignin. Our results are consistent with organoautotrophic growth of a bathyarchaeotal group with lignin as an energy source and bicarbonate as a carbon source and shed light into the cycling of one of Earth's most abundant biopolymers in anoxic marine sediment.

Exploring the Maternal and Infant Oral Microbiomes: A Pilot Study.

Setting the stage for good oral health early in life is critical to long-term oral and overall health. This exploratory study aimed to characterize and compare maternal and newborn oral microbiota among mother-infant pairs. Oral samples were collected from 34 pregnant African American women and their infants at 1 to 3 months of age. Extracted 16SrRNA genes were matched to the Human Oral Microbiome Database. Alpha and beta diversity differed significantly between overall maternal and infant microbiomes. Maternal or infant alpha diversity, however, was not differentiated by maternal gingival status. Several demographic and behavioral variables were associated with, but not predictive of, maternal oral microbiome alpha diversity. There was no association, however, among birth mode, feeding mode, and the infant oral microbiome. Megasphaera micronuciformis was the only periodontal pathogen detected among the infants. Notably, maternal gingival status was not associated with the presence/absence of most periodontal pathogens. This study provides an initial description of the maternal and infant oral microbiomes, laying the groundwork for future studies. The perinatal period presents an important opportunity where perinatal nurses and providers can provide oral assessment, education, and referral to quality dental care.

Comparative Analyses of Subgingival Microbiome in Chronic Periodontitis Patients with and Without IgA Nephropathy by High Throughput 16S rRNA Sequencing.

BACKGROUND/AIMS: Periodontitis is a prevalent chronic inflammatory disease caused by enhanced inflammation induced by dysbiotic microbes forming on subgingival tooth sites, which may disturb the balance of the microbial composition in the biofilm and finally result in the progressive destruction of the periodontal ligament and alveolar bone with periodontal pocket formation and/or gingival recession. METHODS: To elucidate the correlation between subgingival microbiome and IgAN incidence in CP (chronic periodontitis at severe levels) patients, subgingival plaque samples were collected from CP patients without IgAN (Control) and CP patients with IgAN (Disease). 16S rRNA sequencing and comparative analyses of plaque bacterial microbiome between Control and Disease were performed. RESULTS: Subgingival microbial diversity in Disease was a little higher than that in Control. Besides, significant differences were found in subgingival microbiome between Disease and Control. Compared with that in Control, at phylum level, the abundances of Proteobacteria and Actinobacteria were significantly higher while the abundances of Bacteroidetes, Fusobacteria, Spirochaetae, Synergistetes, and Saccharibacteria were significantly lower in Disease; at class level, the abundances of Betaproteobacteria, Bacilli, Actinobacteria, Flavobacteriia, and Gammaproteobacteria were significantly higher while the abundances of Bacteroidia, Fusobacteriia, Negativicutes, Clostridia, and Spirochaetes were significantly lower in Disease; at genus level, the abundances of Bergeyella, Capnocytophaga, Actinomyces, Corynebacterium, Comamonas, Lautropia, and Streptococcus were significantly higher while the abundances of Treponema and Prevotella were significantly lower in Disease. CONCLUSIONS: Our data indicated a correlation between the changes in subgingival microbial structure and IgAN incidence in CP patients, which might be used to predict IgAN incidence in CP patients.

Anaerobic digestion of spent mushroom substrate under thermophilic conditions: performance and microbial community analysis.

Spent mushroom substrate (SMS) is the residue of edible mushroom production occurring in huge amounts. The SMS residue can be digested for biogas production in the mesophilic anaerobic digestion. In the present study, performance of batch thermophilic anaerobic digestion (TAD) of SMS was investigated as well as the interconnected microbial population structure changes. The analyzed batch TAD process lasted for 12 days with the cumulative methane yields of 177.69 mL/g volatile solid (VS). Hydrolytic activities of soluble sugar, crude protein, and crude fat in SMS were conducted mainly in the initial phase, accompanied by the excessive accumulation of volatile fatty acids and low methane yield. Biogas production increased dramatically from days 4 to 6. The degradation rates of cellulose and hemicellulose were 47.53 and 55.08%, respectively. The high-throughput sequencing of 16S rRNA gene amplicons revealed that Proteobacteria (56.7%-62.8%) was the dominant phylum in different fermentative stages, which was highly specific compared with other anaerobic processes of lignocellulosic materials reported in the literature. Crenarchaeota was abundant in the archaea. The most dominant genera of archaea were retrieved as Methanothermobacter and Methanobacterium, but the latter decreased sharply with time. This study shows that TAD is a feasible method to handle the waste SMS.

Elizabethkingia miricola as an opportunistic oral pathogen associated with superinfectious complications in humoral immunodeficiency: a case report.

BACKGROUND: Elizabethkingia miricola is a rare Gram-negative bacterium found in water and clinical specimens. Typical culturing methods often misidentify Elizabethkingia spp. as Flavobacterium or Chryseobacterium. Although diagnosis is based on culturing samples taken from sterile sites, such as blood, a proper identification of this bacterium requires an expertise that goes beyond the capabilities of a typical clinical laboratory. CASE PRESENTATION: A 35-year-old woman diagnosed with common variable immunodeficiency was admitted to our center. Previous treatment with antibiotics (amoxicillin plus clavulanate, first and third generation of cephalosporins, macrolides) and systemic corticosteroids (up to 120 mg/day of prednisolone) failed to arrest the spread of inflammation. Gingival recession was observed in her oral cavity, resulting in an apparent lengthening of her teeth. In addition to typical commensal bacteria, including streptococci and neisseriae, strains of Rothia mucilaginosa and Elizabethkingia miricola were identified upon a detailed microbiological examination using a MALDI-TOF MS Biotyper system. The presence of the latter strain correlated with severe periodontitis, lack of IgA in her saliva and serum, a very low IgG concentration (< 50 mg/dl), IgM-paraproteinemia, decreases in C3a and C5a and microvascular abnormality. High-dose immunoglobulin (to maintain IgG > 500 mg/dl) and targeted levofloxacin treatment resulted in immune system reconstitution, oral healing, and eradication of the Elizabethkingia infection. CONCLUSIONS: E. miricola rarely causes disease in healthy individuals. However, the overgrowth of commensal bacteria, lack of IgG/IgA, microvasculopathy and complement cascade activation in patients with humoral immunodeficiency may facilitate Elizabethkingia invasion. Overuse of antibiotics, particularly beta-lactams, may cause mucosal colonization by E. miricola, followed by its multiplication combined with periodontitis that prompts bacterial translocation. MALDI-TOF Biotyper analysis may become a method of choice for identification of Elizabethkingia infections.

Impact of aluminum chloride on process performance and microbial community structure of granular sludge in an upflow anaerobic sludge blanket reactor for natural rubber processing wastewater treatment.

In this study, granular sludge formation was carried out using an aluminum chloride supplement in an upflow anaerobic sludge blanket (UASB) reactor treating natural rubber processing wastewater. Results show that during the first 75 days after the start-up of the UASB reactor with an organic loading rate (OLR) of 2.65 kg-COD·m(-3)·day(-1), it performed stably with a removal of 90% of the total chemical oxygen demand (COD) and sludge still remained in small dispersed flocs. However, after aluminum chloride was added at a concentration of 300 mg·L(-1) and the OLR range was increased up to 5.32 kg-COD·m(-3)·day(-1), the total COD removal efficiency rose to 96.5 ± 2.6%, with a methane recovery rate of 84.9 ± 13.4%, and the flocs began to form granules. Massively parallel 16S rRNA gene sequencing of the sludge retained in the UASB reactor showed that total sequence reads of Methanosaeta sp. and Methanosarcina sp., reported to be the key organisms for granulation, increased after 311 days of operation. This indicates that the microbial community structure of the retained sludge in the UASB reactor at the end of the experiment gave a good account of itself in not only COD removal, but also granule formation.