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Applied and Environmental Microbiology May 2017Iron artifacts are common among the findings of archaeological excavations. The corrosion layer formed on these objects requires stabilization after their recovery,...
Iron artifacts are common among the findings of archaeological excavations. The corrosion layer formed on these objects requires stabilization after their recovery, without which the destruction of the item due to physicochemical damage is likely. Current technologies for stabilizing the corrosion layer are lengthy and generate hazardous waste products. Therefore, there is a pressing need for an alternative method for stabilizing the corrosion layer on iron objects. The aim of this study was to evaluate an alternative conservation-restoration method using bacteria. For this, anaerobic iron reduction leading to the formation of stable iron minerals in the presence of chlorine was investigated for two strains of (strains TCE1 and LBE). Iron reduction was observed for soluble Fe(III) phases as well as for akaganeite, the most troublesome iron compound in the corrosion layer of archaeological iron objects. In terms of biogenic mineral production, differential efficiencies were observed in assays performed on corroded iron coupons. Strain TCE1 produced a homogeneous layer of vivianite covering 80% of the corroded surface, while on the coupons treated with strain LBE, only 10% of the surface was covered by the same mineral. Finally, an attempt to reduce iron on archaeological objects was performed with strain TCE1, which led to the formation of both biogenic vivianite and magnetite on the surface of the artifacts. These results demonstrate the potential of this biological treatment for stabilizing archaeological iron as a promising alternative to traditional conservation-restoration methods. Since the Iron Age, iron has been a fundamental material for the building of objects used in everyday life. However, due to its reactivity, iron can be easily corroded, and the physical stability of the object built is at risk. This is particularly true for archaeological objects on which a potentially unstable corrosion layer is formed during the time the object is buried. After excavation, changes in environmental conditions (e.g., higher oxygen concentration or lower humidity) alter the stability of the corrosion layer and can lead to the total destruction of the object. In this study, we demonstrate the feasibility of an innovative treatment based on bacterial iron reduction and biogenic mineral formation to stabilize the corrosion layer and protect these objects.
Topics: Archaeology; Corrosion; Desulfitobacterium; Ferric Compounds; Iron; Oxidation-Reduction
PubMed: 28283522
DOI: 10.1128/AEM.03478-16 -
Nutrients Nov 2022This study aims to analyze the relationship between gut microbiota composition and health parameters through specific biochemical markers and food consumption patterns...
This study aims to analyze the relationship between gut microbiota composition and health parameters through specific biochemical markers and food consumption patterns in the Spanish population. This research includes 60 Spanish adults aged 47.3 ± 11.2 years old. Biochemical and anthropometric measurements, and a self-referred dietary survey (food frequency questionnaire), were analyzed and compared with the participant´s gut microbiota composition analyzed by 16s rDNA sequencing. Several bacterial strains differed significantly with the biochemical markers analyzed, suggesting an involvement in the participant´s metabolic health. Lower levels of Lactobacillaceae and Oscillospiraceae and an increase in Pasteurellaceae, , and were observed in individuals with higher AST levels. Higher levels of the Christensenellaceae and a decrease in Peptococcaceae were associated with higher levels of HDL-c. High levels of and and low levels of were found in individuals with higher insulin levels. This study also identified associations between bacteria and specific food groups, such as an increase in lactic acid bacteria with the consumption of fermented dairy products or an increase in Verrucomicrobiaceae with the consumption of olive oil. In conclusion, this study reinforces the idea that specific food groups can favorably modulate gut microbiota composition and have an impact on host´s health.
Topics: Adult; Humans; Middle Aged; Gastrointestinal Microbiome; Diet; Verrucomicrobia; Cultured Milk Products; Lactobacillaceae
PubMed: 36500996
DOI: 10.3390/nu14234966 -
Frontiers in Cellular and Infection... 2017The oral microbiota plays a critical role in both local and systemic inflammation. Metabolic syndrome (MetS) is characterized by low-grade inflammation, and many studies...
The oral microbiota plays a critical role in both local and systemic inflammation. Metabolic syndrome (MetS) is characterized by low-grade inflammation, and many studies have been conducted on the gut microbiota from stool specimens. However, the etiological role of the oral microbiota in the development of MetS is unclear. In this study, we analyzed the oral and gut microbiome from 228 subgingival plaque and fecal samples from a Korean twin-family cohort with and without MetS. Significant differences in microbial diversity and composition were observed in both anatomical niches. However, a host genetic effect on the oral microbiota was not observed. A co-occurrence network analysis showed distinct microbiota clusters that were dependent on the MetS status. A comprehensive analysis of the oral microbiome identified and as bacteria enriched in subjects with MetS and as bacteria abundant in healthy controls. Validation of the identified oral bacteria by quantitative PCR (qPCR) showed that healthy controls possessed significantly lower levels of . ( = 0.023) and a higher ratio of to ( < 0.05) than MetS subjects. Our results support that local oral microbiota can be associated with systemic disorders. The microbial biomarkers identified in this study would aid in determination of which individuals develop chronic diseases from their MetS and contribute to strategic disease management.
Topics: Adult; Aged; Biomarkers; Carnobacteriaceae; Dental Plaque; Feces; Female; Humans; Male; Metabolic Syndrome; Microbiota; Middle Aged; Mouth; Neisseria; Peptococcus; Real-Time Polymerase Chain Reaction
PubMed: 29326886
DOI: 10.3389/fcimb.2017.00516 -
Scientific Reports Jun 2017Due to their antimicrobial properties, silver nanoparticles (AgNPs) are being used in non-edible and edible consumer products. It is not clear though if exposure to...
Due to their antimicrobial properties, silver nanoparticles (AgNPs) are being used in non-edible and edible consumer products. It is not clear though if exposure to these chemicals can exert toxic effects on the host and gut microbiome. Conflicting studies have been reported on whether AgNPs result in gut dysbiosis and other changes within the host. We sought to examine whether exposure of Sprague-Dawley male rats for two weeks to different shapes of AgNPs, cube (AgNC) and sphere (AgNS) affects gut microbiota, select behaviors, and induces histopathological changes in the gastrointestinal system and brain. In the elevated plus maze (EPM), AgNS-exposed rats showed greater number of entries into closed arms and center compared to controls and those exposed to AgNC. AgNS and AgNC treated groups had select reductions in gut microbiota relative to controls. Clostridium spp., Bacteroides uniformis, Christensenellaceae, and Coprococcus eutactus were decreased in AgNC exposed group, whereas, Oscillospira spp., Dehalobacterium spp., Peptococcaeceae, Corynebacterium spp., Aggregatibacter pneumotropica were reduced in AgNS exposed group. Bacterial reductions correlated with select behavioral changes measured in the EPM. No significant histopathological changes were evident in the gastrointestinal system or brain. Findings suggest short-term exposure to AgNS or AgNC can lead to behavioral and gut microbiome changes.
Topics: Aggregatibacter; Animals; Bacteroides; Brain; Clostridium; Corynebacterium; Dysbiosis; Feces; Gastrointestinal Microbiome; Gastrointestinal Tract; Humans; Metal Nanoparticles; Peptococcus; Rats; Rats, Sprague-Dawley
PubMed: 28588204
DOI: 10.1038/s41598-017-02880-0 -
The ISME Journal Mar 2017Two novel chlorinated alkane-respiring Dehalobacter restrictus strains CF and DCA were isolated from the same enrichment culture, ACT-3, and characterized. The closed...
Two novel chlorinated alkane-respiring Dehalobacter restrictus strains CF and DCA were isolated from the same enrichment culture, ACT-3, and characterized. The closed genomes of these highly similar sister strains were previously assembled from metagenomic sequence data and annotated. The isolation of the strains enabled experimental verification of predicted annotations, particularly focusing on irregularities or predicted gaps in central metabolic pathways and cofactor biosynthesis. Similar to D. restrictus strain PER-K23, strains CF and DCA require arginine, histidine and threonine for growth, although the corresponding biosynthesis pathways are predicted to be functional. Using strain CF to experimentally verify annotations, we determined that the predicted defective serine biosynthesis pathway can be rescued with a promiscuous serine hydroxymethyltransferase. Strain CF grew without added thiamine although the thiamine biosynthesis pathway is predicted to be absent; intracellular thiamine diphosphate, the cofactor of carboxylases in central metabolism, was not detected in cell extracts. Thus, strain CF may use amino acids to replenish central metabolites, portending entangled metabolite exchanges in ACT-3. Consistent with annotation, strain CF possesses a functional corrinoid biosynthesis pathway, demonstrated by increasing corrinoid content during growth and guided cobalamin biosynthesis in corrinoid-free medium. Chloroform toxicity to corrinoid-producing methanogens and acetogens may drive the conservation of corrinoid autotrophy in Dehalobacter strains. Heme detection in strain CF cell extracts suggests the 'archaeal' heme biosynthesis pathway also functions in anaerobic Firmicutes. This study reinforces the importance of incorporating enzyme promiscuity and cofactor availability in genome-scale functional predictions and identifies essential nutrient interdependencies in anaerobic dechlorinating microbial communities.
Topics: Autotrophic Processes; Biosynthetic Pathways; Biotin; Chloroform; Corrinoids; Heme; Peptococcaceae; Water Microbiology
PubMed: 27898054
DOI: 10.1038/ismej.2016.158 -
Microbiology Spectrum Jan 2022Bacillus amyloliquefaciens is a nonpathogenic microorganism whose highly active amylase is widely isolated from soil and plants. TL106 is an isolate of Bacillus...
Bacillus amyloliquefaciens is a nonpathogenic microorganism whose highly active amylase is widely isolated from soil and plants. TL106 is an isolate of Bacillus amyloliquefaciens isolated from cold- and disease-resistant Tibetan pigs in Linzhi, Tibet. Here, we report that TL106 not only could survive in acidic environments, high bile salt concentrations, and high-temperature conditions but also was resistant to antibiotics. It significantly improved the growth performance of weaned piglets, especially in the prevention of diarrhea. The crude fiber and crude ash digestibility in weaned piglets after TL106 administration was considerably higher than that in other groups. The results of 16S rRNA sequencing conveyed that TL106 stabilized gut microbiota that was disturbed by the weaning process with an increased level of , , , and . Hence, this study proved that Bacillus amyloliquefaciens TL106 might be a candidate for antibiotics in Duroc×Landrace×Yorkshire weaned piglets. Antibiotics are often used to promote animal growth and prevent diarrhea in weanling piglets. Nevertheless, intestinal pathogenic bacterial resistance and drug residues caused by antibiotic overuse are worthy of concern and demand an urgent solution. Bacillus amyloliquefaciens TL106 has been isolated from cold- and disease-resistant Tibetan pigs in Linzhi, Tibet. It significantly improved the growth performance, decreased diarrhea, increased the absorption of crude substances, and regulated the gut flora homeostasis in Duroc×Landrace×Yorkshire weaned piglets. As an antibiotic candidate, TL106 perfectly displayed its probiotic potential and pollution-free properties.
PubMed: 35080439
DOI: 10.1128/spectrum.01205-21 -
Current Microbiology May 2021Degradation of acetone and higher ketones has been described in detail for aerobic and nitrate-reducing bacteria. Among sulfate-reducing bacteria, degradation of acetone...
Degradation of acetone and higher ketones has been described in detail for aerobic and nitrate-reducing bacteria. Among sulfate-reducing bacteria, degradation of acetone and other ketones is still an uncommon ability and has not been understood completely yet. In the present work, we show that Desulfotomaculum arcticum and Desulfotomaculum geothermicum are able to degrade acetone and butanone. Total proteomics of cell-free extracts of both organisms indicated an involvement of a thiamine diphosphate-dependent enzyme, a B-dependent mutase, and a specific dehydrogenase during acetone degradation. Similar enzymes were recently described to be involved in acetone degradation by Desulfococcus biacutus. As there are so far only two described sulfate reducers able to degrade acetone, D. arcticum and D. geothermicum represent two further species with this capacity. All these bacteria appear to degrade acetone via the same set of enzymes and therefore via the same pathway.
Topics: Acetone; Deltaproteobacteria; Desulfotomaculum; Ketones; Peptococcaceae
PubMed: 33751185
DOI: 10.1007/s00284-021-02441-9 -
Journal of Microbiology and... May 2016Tylosin has been used as a livestock feed additive and antibiotic growth promoter for many years. However, the mode of action by which tylosin enhances animal growth is...
Tylosin has been used as a livestock feed additive and antibiotic growth promoter for many years. However, the mode of action by which tylosin enhances animal growth is unclear. We used high-throughput sequencing of 16S rRNA genes to investigate the effects of tylosin as a feed additive on swine gut microbiota. No significant difference in the rate of weight increase was observed between control and tylosin-treated pigs during a 10-week feeding trial. However, tylosin-treated pigs showed rapid increases in the relative abundance of the phylum Firmicutes. Increases in Firmicutes species are associated with (so-called) obese-type gut microbiota. The abundance of species of four families of the phylum Firmicutes (Streptococcaceae, Peptococcaceae, Peptostreptococcaceae, and Clostridiaceae) correlated positively with host weight gain. The abundance of Streptococcaceae family bacteria was least affected by tylosin treatment. Distribution analysis of operational taxonomic units (OTUs) showed that both control and tylosin-treated pigs exhibited similar OTU alterations during growth. However, the tylosin-treated group showed distinctive alterations in gut microbiota when the host weighed approximately 60 kg, whereas similar alterations occurred at around 80 kg in the control group. Our results suggest that use of tylosin accelerates maturation of swine gut microbiota rather than altering its composition.
Topics: Animal Feed; Animals; Anti-Bacterial Agents; Bacteria; DNA, Bacterial; Gastrointestinal Microbiome; Gram-Positive Bacteria; Growth Substances; Metagenome; Models, Animal; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Swine; Tylosin; Weight Gain
PubMed: 26869601
DOI: 10.4014/jmb.1512.12004 -
Frontiers in Pharmacology 2022oil is rich in unsaturated fatty acids such as inoleic acid (47.11%) and oleic acid (23.81%). Our research demonstrates that it exerts a protective effect on rat models...
oil is rich in unsaturated fatty acids such as inoleic acid (47.11%) and oleic acid (23.81%). Our research demonstrates that it exerts a protective effect on rat models of pulmonary fibrosis, however, little is known regarding the underlying mechanism of action. This study aimed to characterize the therapeutic mechanism of action of oil on bleomycin-induced pulmonary fibrosis in rats. oil appears to regulate the levels of potential key serum biomarkers which include tetrahydrobiopterin, L-serine, citrulline and estradiol to participate in folate biosynthesis, glycine, serine and threonine metabolism, arginine biosynthesis and steroid hormone biosynthesis. And it also enriched intestinal microbial abundance, homogeneity and modulated the abundance of , Peptococcaceae, , , Lachnospiraceae to exert a protective effect against pulmonary fibrosis. oil appears to confer protective effects against pulmonary fibrosis by affecting the level of pulmonary fibrosis metabolites and the abundance of related intestinal flora through multiple targets, as evidenced by our untargeted LC-MS/MS metabonomics evaluation and 16S rDNA sequencing technology.
PubMed: 36386194
DOI: 10.3389/fphar.2022.1037563 -
Microorganisms Jul 2020The aim was to assess the gut microbiota of long-livers from Moscow. This study included two groups of patients who signed their consent to participate. The group of...
The aim was to assess the gut microbiota of long-livers from Moscow. This study included two groups of patients who signed their consent to participate. The group of long-livers (LL) included 20 participants aged 97-100 years (4 men and 16 women). The second group included 22 participants aged 60-76 years (6 men) without clinical manifestations of chronic diseases (healthy elderly). Gut microbiota was studied by 16S rRNA sequencing. Long-livers underwent a complex geriatric assessment as well as expanded blood biochemistry. Gut microbiota composition in the cohorts was also compared with microbiome in long-livers from Japan and Italy. Russian long-livers' microbiome contained more beneficial bacteria than healthy elderly including families. Conditional pathogens like were more abundant in the healthy elderly. Compared with Italian and Japanese microbiome LL, the Russian LL appeared to be more similar to the Italian cohort. and balances were associated with femoral and carotid intima-media thickness, respectively. balance was assessed with the folic acid level and the with Mini Nutritional Assessment score. Long-livers' microbiome appeared to be unexpectedly balanced. The high representation of beneficial bacteria in long-livers may prevent them from low-grade inflammation and thus protect them from the development of atherosclerosis and other aging-associated conditions.
PubMed: 32751673
DOI: 10.3390/microorganisms8081162