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1.
Food Chem ; 367: 130735, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34365247

RESUMO

Green and black teas are regarded to possess therapeutic potential for the treatment of obesity, however it is not clear which tea performs better in body weight control. In this study, aiming to eliminate cultivar variation, green tea phenolics (GTP) were oxidized by tyrosinase to obtain oxidized tea phenolics (OTP). Thereafter, their anti-obesity effect on high-fat diet induced obese mice were compared. The results showed that despite their distinctive phenolic profiles, GTP and OTP exerted similar anti-obesity properties after 12 weeks of dietary intervention. Furthermore, cecal microbiota profiling exhibited comparable modulatory effects of GTP and OTP on multiple bacterial taxa, including Parabacteroides distasonis, Bifidobacterium, Prevotella, and Akkermansia muciniphila, which were strongly associated with obesity related indexes. Putative bacterial function profiling implicated that both GTP and OTP might regulate the lipid metabolism similarly. Collectively, the oxidation of GTP did not influence the anti-obesity and gut microbiota modulatory effects to any large extent.


Assuntos
Microbioma Gastrointestinal , Chá , Animais , Bacteroidetes , Camundongos , Camundongos Obesos , Obesidade/tratamento farmacológico , Obesidade/etiologia
2.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34633922

RESUMO

A Gram-stain-negative, ovoid or rod-shaped, non-flagellated, motile-by-gliding and aerobic bacteria, designated S10-8T, was isolated from marine sediment of the Yellow Sea. Colonies of strain S10-8T had a pink-red pigmentation and its cells were approximately 0.5-0.8 µm×1.0-2.5 µm in size. Growth occurred at 10-45 °C (optimally at 33-37 °C), in the presence of 0-12.0 % NaCl (optimally at 2.0-5.0 %, w/v) and at pH 5.0-8.5 (optimally at pH 7.0-7.5). Phylogenetic analysis of the 16S rRNA gene indicated that strain S10-8T is a member of the genus Pontibacter within the family Hymenobacteraceae, and the 16S rRNA gene sequence similarity of strain S10-8T to its closest relative Pontibacter actiniarum KCTC 12367T was 96.9 %. Strain S10-8T contained MK-7 as the predominant menaquinone and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B) and iso-C15:0 as the major fatty acids. The major polar lipids were phosphatidylethanolamine, an unidentified aminophospholipid and an unidentified lipid. The size of the draft genome was 4 623 791 bp and the G+C content was 53.5 mol%. There were low DNA-DNA hybridization values (<48.3±5.2 %) and average nucleotide identity values (<86.5 %) between strain S10-8T and the most closely related recognized Pontibacter species. Therefore, we propose a novel species in the genus Pontibacter to accommodate the novel isolate: Pontibacter flavimaris sp. nov. (type strain S10-8T=KCTC 42769T=ACCC 19859T).


Assuntos
Ácidos Graxos , Sedimentos Geológicos , Técnicas de Tipagem Bacteriana , Bacteroidetes , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34623951

RESUMO

A Gram-stain-negative, non-motile, rod-shaped, aerobic bacterium (designated as LMIT005T) was isolated from shrimp ponds in Shantou, China. The new isolate was characterized taxonomically using a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain LMIT005T was found to be affiliated with the family Cyclobacteriaceae of the order Cytophagales while appearing as a distinct lineage. The 16S rRNA gene sequence similarity between strain LMIT005T and Algoriphagus yeomjeoni KCTC 12309T, the closest type strain in the family, was 91.3 %. Strain LMIT005T grew optimally at 25 °C, pH 7 and in the presence of 2.0 % (w/v) NaCl. The DNA G+C content (data from genome sequence) was 40.5 mol%. Compared with reference strain A. yeomjeoni KCTC 12309T, the average nucleotide identity (ANI) of LMIT005T was 70 %. The sole respiratory quinone of LMIT005T was menaquinone (MK-7), and the major fatty acids were summed feature 3 (C16 : 1 ω6c / C16 : 1 ω7c). The polar lipids of strain LMIT005T were mainly composed of phosphatidylethanolamine, phosphatidylcholine, two unidentified amino lipids, two unidentified lipids, one unidentified glycolipid and one unidentified phospholipid. The draft genome of strain LMIT005T comprised 3 089 781 bp (3.09 Mb) nucleotides and 2773 genes. Antimicrobial resistant-related genes (blal, mexA, and mexb) were annotated in the genome of strain LMIT005T, which indicated that it might be able to resist ß-lactam antibiotics. This was further verified by antimicrobial resistant test. Given its distinct genomic, morphological, and physiological differences from previously described type strains, strain LMIT005T is proposed as a representative of a novel genus of the family Cyclobacteriaceae, with the name Penaeicola halotolerans gen. nov., sp. nov. The type strain is LMIT005T (=KCTC 82616T=CICC 25047T).


Assuntos
Lagoas , Água do Mar , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500631

RESUMO

The 'core' metabolome of the Bacteroidetes genus Chitinophaga was recently discovered to consist of only seven metabolites. A structural relationship in terms of shared lipid moieties among four of them was postulated. Here, structure elucidation and characterization via ultra-high resolution mass spectrometry (UHR-MS) and nuclear magnetic resonance (NMR) spectroscopy of those four lipids (two lipoamino acids (LAAs), two lysophosphatidylethanolamines (LPEs)), as well as several other undescribed LAAs and N-acyl amino acids (NAAAs), identified during isolation were carried out. The LAAs represent closely related analogs of the literature-known LAAs, such as the glycine-serine dipeptide lipids 430 (2) and 654. Most of the here characterized LAAs (1, 5-11) are members of a so far undescribed glycine-serine-ornithine tripeptide lipid family. Moreover, this study reports three novel NAAAs (N-(5-methyl)hexanoyl tyrosine (14) and N-(7-methyl)octanoyl tyrosine (15) or phenylalanine (16)) from Olivibacter sp. FHG000416, another Bacteroidetes strain initially selected as best in-house producer for isolation of lipid 430. Antimicrobial profiling revealed most isolated LAAs (1-3) and the two LPE 'core' metabolites (12, 13) active against the Gram-negative pathogen M. catarrhalis ATCC 25238 and the Gram-positive bacterium M. luteus DSM 20030. For LAA 1, additional growth inhibition activity against B. subtilis DSM 10 was observed.


Assuntos
Aminoácidos/química , Aminoácidos/farmacologia , Bacteroidetes/metabolismo , Glicerofosfolipídeos/química , Glicerofosfolipídeos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas de Tipagem Bacteriana/métodos
5.
Appl Microbiol Biotechnol ; 105(19): 7475-7486, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34487206

RESUMO

The dietary supplementation of prebiotics is considered a promising strategy for the modulation of gut microbiota. Due to the wide variety of animal models and tremendous inter-individual variability from human investigations, the prebiotic effect of fibers is often difficult to compare between studies. Here, the effects of 11 dietary fibers on human fecal microbiota were studied using an in vitro human fecal fermentation model under well-controlled conditions. All fibers showed positive regulatory effects on short chain fatty acids (SCFAs) and several beneficial bacteria, including Parabacteroides distasonis and Bifidobacterium spp. Cultures supplemented with xylo-oligosaccharide and konjac flour showed the highest SCFAs. According to regulatory effects, fibers were divided into three groups, with 13 indicator OTUs (operational taxonomic units) identified. Fecal microbiota regulated by isomalto-oligosaccharide and chitosan-oligosaccharide were similar to fructo-oligosaccharide and inulin outputs. As a supplement to in vivo studies, our results comprehensively summarized the similarities and distinctiveness of fibers in regulating fecal microbiota structures. KEY POINTS: • Fibers were divided into three groups based on the regulatory effects in microbiota. • Thirteen indicator OTUs were identified using pairwise comparisons. • Fiber similarities and distinctive traits in regulating microbiota effect were identified.


Assuntos
Microbiota , Bacteroidetes , Fermentação , Humanos
6.
Water Res ; 204: 117601, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481286

RESUMO

The conversion of organic wastes/wastewater into medium chain fatty acids (MCFAs) such as caproate has attracted much attention, while the effects of toxic compounds on the process have rarely been studied. The present study investigated the effects of phenol (0-1.5 g/L), which is a toxicant and present in various organic wastes, on the caproate production in the chain elongation (CE) process with ethanol as electron donor via two-stage batch anaerobic fermentation of glucose. The results showed phenol ≤ 1 g/L did not affect short chain fatty acids (SCFAs) production, while 1 g/L phenol increased caproate production by 59.9% in the following CE process. The higher selectivity of caproate and higher consumption of ethanol contributed to the higher caproate production at 1 g/L phenol. It was also shown 1 g/L phenol had more positive effect on CE of butyrate than acetate. 1.5 g/L phenol inhibited both SCFAs production and CE processes. 16S rRNA genes analysis showed phenol had slight effect on the microbial communities for SCFAs production, while it obviously changed the dominant microbes in CE process. For CE process, metagenomic analysis was further conducted and phenol mainly affected fatty acid biosynthesis (FAB) pathway, but not reverse ß-oxidization (RBO) pathway. 1 g/L phenol increased the abundances of genes in FAB pathway, which could be related with the higher caproate production. Genome reconstruction identified the dominant microbial species in CE process, which were changed with different concentrations of phenol. Most of the dominant species were new microbial species potentially involved in CE. The syntrophic cooperation between Petrimonas mucosa FDU058 and Methanofollis sp. FDU007 might play important role in increased caproate production at 1 g/L phenol, and their adaption to phenol could be due to the presence of genes relating with active efflux system and refolding of proteins.


Assuntos
Etanol , Fenol , Anaerobiose , Bacteroidetes , Reatores Biológicos , Caproatos , Elétrons , Fermentação , Fenóis , RNA Ribossômico 16S/genética
7.
Nat Commun ; 12(1): 5308, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489463

RESUMO

Climate change is altering the frequency and severity of drought events. Recent evidence indicates that drought may produce legacy effects on soil microbial communities. However, it is unclear whether precedent drought events lead to ecological memory formation, i.e., the capacity of past events to influence current ecosystem response trajectories. Here, we utilize a long-term field experiment in a mountain grassland in central Austria with an experimental layout comparing 10 years of recurrent drought events to a single drought event and ambient conditions. We show that recurrent droughts increase the dissimilarity of microbial communities compared to control and single drought events, and enhance soil multifunctionality during drought (calculated via measurements of potential enzymatic activities, soil nutrients, microbial biomass stoichiometry and belowground net primary productivity). Our results indicate that soil microbial community composition changes in concert with its functioning, with consequences for soil processes. The formation of ecological memory in soil under recurrent drought may enhance the resilience of ecosystem functioning against future drought events.


Assuntos
Secas/estatística & dados numéricos , Microbiota/fisiologia , Microbiologia do Solo , Solo/química , Água/análise , Acidobacteria/classificação , Acidobacteria/genética , Acidobacteria/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Altitude , Áustria , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Biomassa , Carbono/análise , Chloroflexi/classificação , Chloroflexi/genética , Chloroflexi/isolamento & purificação , Pradaria , Humanos , Nitrogênio/análise , Fósforo/análise , Planctomycetales/classificação , Planctomycetales/genética , Planctomycetales/isolamento & purificação , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Enxofre/análise , Verrucomicrobia/classificação , Verrucomicrobia/genética , Verrucomicrobia/isolamento & purificação
8.
Artigo em Inglês | MEDLINE | ID: mdl-34382925

RESUMO

A novel Gram-stain-negative strain, WQ 117T, isolated from the faeces of Rhinopithecus bieti collected at Yunnan Snub-nosed Monkey National Park, Yunnan province, PR China, was subjected to a polyphasic taxonomic study. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate represented a member of the genus Faecalibacter, sharing 97.64 % sequence similarity with the type strain Faecalibacter macacae YIM 102668T. The G+C content of the genomic DNA of WQ117T was 30.5 mol%. The predominant isoprenoid quinone was MK-6. The major cellular fatty acids was iso-C15 : 0. The whole genome average nucleotide identity (gANI) values and the digital DNA-DNA hybridization values between WQ 117T and YIM 102668T were 79.66 % and 22.20 %, respectively. Growth occurred at 0-50 °C (optimally at 28-35 °C), pH 7.0-9.0 (optimally at pH 8.0) and with 0-2 % (w/v) NaCl (optimally without NaCl). On the basis of the taxonomic evidence, a novel species, Faecalibacter rhinopitheci sp. nov., is proposed. The type strain is WQ 117T (=KCTC 82394T=CCTCC AA 2020027T).


Assuntos
Bacteroidetes/classificação , Filogenia , Presbytini , Animais , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Presbytini/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-34427552

RESUMO

A Gram-stain-negative, non-motile bacterial strain, designated SW124T, was isolated from a deep-sea sediment sample collected from the Indian Ocean. SW124T was aerobic and catalase-positive. The strain grew at 4-40 °C (optimum, 30 °C), at pH 5.0-8.6 (optimum, pH 7.0) and in the presence of 0.5-9.5 % (w/v) NaCl (optimum, 3.0%). The results of comparative analyses of the 16S rRNA gene sequence indicated that SW124T was grouped in the vicinity of the genus Rhodonellum in the family Cyclobacteriaceae. The quinone system contained menaquinone MK-7. The predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). SW124T contained phosphatidylethanolamine (PE) as the major polar lipid. The genomic DNA G+C content of SW124T was 41.7 mol%. On the basis of its phenotypic characteristics and phylogenetic data, we propose that strain SW124T (=CGMCC 1.16171T=KCTC 82235T) represents a novel species of a novel genus, with the name Pararhodonellum marinum gen. nov., sp. nov.


Assuntos
Bacteroidetes/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Índico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA
10.
Syst Appl Microbiol ; 44(5): 126245, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34392063

RESUMO

A novel anaerobic bacterium (strain M08_MBT) was isolated from a terrestrial mud volcano (Taman Peninsula, Russia). Gram-stain-negative cells were straight and slender rods with gliding motility, occasionally forming long filaments. The isolate was mesophilic, slightly halo- and alkaliphilic chemoorganoheterotroph, growing on carbohydrates (starch, dextrin, pectin, glucose, fructose, mannose, maltose, trehalose, lactose, sucrose) and proteinaceous compounds (peptone, tryptone, gelatin, casein and albumin). Strain M08_MBT tolerated 3% oxygen in the gas phase while catalase negative. The dominant cellular fatty acids of strain M08_MBT were C15:0, C15:1 and C13:0 acids. 16S rRNA gene sequence analysis revealed that strain M08_MBT belongs to the order Bacteroidales and only distantly related to other cultivated members of this order (85.12-90.01% 16S rRNA gene similarity). The genome of strain M08_MBT had a size of 4.37 Mb with a DNA G + C content of 43.5 mol% (WGS). The genes involved in gliding motility, proteolysis, central carbon metabolism, and oxygen tolerance were listed in genome annotation. Based on the phenotypic and genotypic characteristics, strain M08_MBT represents a novel species of a novel genus within family Tenuifilaceae, with proposed name Perlabentimonas gracilis gen. nov., sp. nov. The type strain is M08_ MBT (=DSM 110720 T = VKM B-3471 T). This is the first representative of Bacteroidales isolated in pure culture from a mud volcano.


Assuntos
Bacteroidetes/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Erupções Vulcânicas
11.
Braz J Biol ; 83: e242818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378656

RESUMO

The study was aimed to assess impact of high fat diet (HFD) and synthetic human gut microbiota (GM) combined with HFD and chow diet (CD) in inducing type-2 diabetes (T2D) using mice model. To our knowledge, this is the first study using selected human GM transplantation via culture based method coupled dietary modulation in mice for in vivo establishment of inflammation leading to T2D and gut dysbiosis. Twenty bacteria (T2D1-T2D20) from stool samples of confirmed T2D subjects were found to be morphologically different and subjected to purification on different media both aerobically and anerobically, which revealed seven bacteria more common among 20 isolates on the basis of biochemical characterization. On the basis of 16S rRNA gene sequencing, these seven isolates were identified as Bacteroides stercoris (MT152636), Lactobacillus acidophilus (MT152637), Lactobacillus salivarius (MT152638), Ruminococcus bromii (MT152639), Klebsiella aerogenes (MT152640), Bacteroides fragilis (MT152909), Clostridium botulinum (MT152910). The seven isolates were subsequently used as synthetic gut microbiome (GM) for their role in inducing T2D in mice. Inbred strains of albino mice were divided into four groups and were fed with CD, HFD, GM+HFD and GM+CD. Mice receiving HFD and GM+modified diet (CD/HFD) showed highly significant (P<0.05) increase in weight and blood glucose concentration as well as elevated level of inflammatory cytokines (TNF-α, IL-6, and MCP-1) compared to mice receiving CD only. The 16S rRNA gene sequencing of 11 fecal bacteria obtained from three randomly selected animals from each group revealed gut dysbiosis in animals receiving GM. Bacterial strains including Bacteroides gallinarum (MT152630), Ruminococcus bromii (MT152631), Lactobacillus acidophilus (MT152632), Parabacteroides gordonii (MT152633), Prevotella copri (MT152634) and Lactobacillus gasseri (MT152635) were isolated from mice treated with GM+modified diet (HFD/CD) compared to strains Akkermansia muciniphila (MT152625), Bacteriodes sp. (MT152626), Bacteroides faecis (MT152627), Bacteroides vulgatus (MT152628), Lactobacillus plantarum (MT152629) which were isolated from mice receiving CD/HFD. In conclusion, these findings suggest that constitution of GM and diet plays significant role in inflammation leading to onset or/and possibly progression of T2D. .


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Animais , Bacteroides , Bacteroidetes , Dieta Hiperlipídica/efeitos adversos , Disbiose , Humanos , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Prevotella , RNA Ribossômico 16S/genética , Ruminococcus
12.
Mol Biol Evol ; 38(9): 3820-3831, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34426845

RESUMO

Intracellular endosymbionts have reduced genomes that progressively lose genes at a timescale of tens of million years. We previously reported that gene loss rate is linked to mutation rate in Blattabacterium, however, the mechanisms causing gene loss are not yet fully understood. Here, we carried out comparative genomic analyses on the complete genome sequences of a representative set of 67 Blattabacterium strains, with sizes ranging between 511 and 645 kb. We found that 200 of the 566 analyzed protein-coding genes were lost in at least one lineage of Blattabacterium, with the most extreme case being one gene that was lost independently in 24 lineages. We found evidence for three mechanisms influencing gene loss in Blattabacterium. First, gene loss rates were found to increase exponentially with the accumulation of substitutions. Second, genes involved in vitamin and amino acid metabolism experienced relaxed selection in Cryptocercus and Mastotermes, possibly triggered by their vertically inherited gut symbionts. Third, we found evidence of epistatic interactions among genes leading to a "domino effect" of gene loss within pathways. Our results highlight the complexity of the process of genome erosion in an endosymbiont.


Assuntos
Bacteroidetes/genética , Baratas/microbiologia , Genoma Bacteriano , Taxa de Mutação , Simbiose/genética , Animais , Seleção Genética
13.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443642

RESUMO

Among industrially important pyridoxal-5'-phosphate (PLP)-dependent transaminases of fold type IV D-amino acid transaminases are the least studied. However, the development of cascade enzymatic processes, including the synthesis of D-amino acids, renewed interest in their study. Here, we describe the identification, biochemical and structural characterization of a new D-amino acid transaminase from Haliscomenobacter hydrossis (Halhy). The new enzyme is strictly specific towards D-amino acids and their keto analogs; it demonstrates one of the highest rates of transamination between D-glutamate and pyruvate. We obtained the crystal structure of the Halhy in the holo form with the protonated Schiff base formed by the K143 and the PLP. Structural analysis revealed a novel set of the active site residues that differ from the key residues forming the active sites of the previously studied D-amino acids transaminases. The active site of Halhy includes three arginine residues, one of which is unique among studied transaminases. We identified critical residues for the Halhy catalytic activity and suggested functions of the arginine residues based on the comparative structural analysis, mutagenesis, and molecular modeling simulations. We suggested a strong positive charge in the O-pocket and the unshaped P-pocket as a structural code for the D-amino acid specificity among transaminases of PLP fold type IV. Characteristics of Halhy complement our knowledge of the structural basis of substrate specificity of D-amino acid transaminases and the sequence-structure-function relationships in these enzymes.


Assuntos
Aminoácidos/metabolismo , Proteínas de Bactérias/metabolismo , Bacteroidetes/metabolismo , Domínio Catalítico/fisiologia , Transaminases/metabolismo , Cristalografia por Raios X/métodos , Modelos Moleculares , Fosfato de Piridoxal/metabolismo , Especificidade por Substrato/fisiologia
14.
Nutrients ; 13(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34444674

RESUMO

Changes in the composition and proportions of the gut microbiota may be associated with numerous diseases, including cognitive impairment. Over the recent years, the growing interest in this relation is observed, but there are still many unknowns, especially in the elderly. To the best of our knowledge, this is the first work that synthesizes and critically evaluates existing evidence on the possible association between human gut microbiota and cognitive function in the elderly. For this purpose, comprehensive literature searches were conducted using the electronic databases PubMed, Google Scholar, and ScienceDirect. The gut microbiota of cognitively healthy and impaired elderly people may differ in the diversity and abundance of individual taxes, but specific taxes cannot be identified. However, some tendencies to changing the Firmicutes/Bacteroidetes ratio can be identified. Currently, clinical trials involving probiotics, prebiotics, and synbiotics supplementation have shown that there are premises for the claim that these factors can improve cognitive functions, however there is no single intervention beneficial to the elderly population. More reliable evidence from large-scale, long-period RCT is needed. Despite proposing several potential mechanisms of the gut microbiota's influence on the cognitive function impairment, prospective research on this topic is extremely difficult to conduct due to numerous confounding factors that may affect the gut microbiota. Heterogeneity of research outcomes impairs insight into these relations.


Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Microbioma Gastrointestinal/fisiologia , Probióticos/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Bacteroidetes/fisiologia , Disfunção Cognitiva/microbiologia , Dieta , Firmicutes/fisiologia , Humanos , Prebióticos/administração & dosagem
15.
Antonie Van Leeuwenhoek ; 114(10): 1647-1655, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34342780

RESUMO

Two novel Gram-negative bacterial strains BT190T and BT191 were isolated from soil collected in Uijeongbu city (37°44'55″N, 127°02'20″E), Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains BT190T and BT191 belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia). The level of 16S rRNA gene sequence similarity between the strains BT190T and BT190 was 99.5%. The strains BT190T and BT191 were closely related to Hymenobacter swuensis DY53T (97.0% 16S rRNA gene similarity), Hymenobacter metallilatus 9PBR-2 T (96.8%), Hymenobacter tibetensis XTM003T (96.8%) and Hymenobacter yonginensis HMD1010T (96.6%). The genome size of strain BT190T was 4,859,864 bp. The DNA G+C content of strain BT190T was 55.3 mol%. Bacterial growth was observed at 4-30 °C (optimum 25 °C) and pH 6.0-9.0 (optimum, pH 6.0-7.0) on R2A agar. Colonies of strains BT190T and BT191 were raised, smooth, circular and red-pink colored. The sole respiratory quinone of strain BT190T was MK-7 and the predominant cellular fatty acids were iso-C15:0, C16:1 ω5c, summed feature 3 (C16:1 ω6c / C16:1 ω7c) and summed feature 4 (iso-C17:1 I / anteiso-C17:1 B). The major polar lipids of strain BT190T were aminophospholipid (APL) and phosphatidylethanolamine (PE). Based on the chemotaxonomic, biochemical, and phylogenetic analysis, strains BT190T and BT191 can be suggested as a novel bacterial species within the genus Hymenobacter, for which the name Hymenobacter puniceus sp. nov is proposed. The type strain of Hymenobacter puniceus is BT190T (= KCTC 72342 T = NBRC 114860 T).


Assuntos
Cytophagaceae , Solo , Bacteroidetes/genética , Cytophagaceae/genética , DNA Bacteriano/genética , Ácidos Graxos , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Microbiologia do Solo
16.
Biomolecules ; 11(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34439821

RESUMO

Irritable bowel syndrome is not a life-threatening disease, yet it significantly affects the quality of life and contributes to economic loss. It is estimated that even up to 45% of the world's population can suffer from the disease. The first attempts to diagnose irritable bowel syndrome were made at the end of the 19th century; however, establishing appropriate diagnostic criteria and treatment methods is still ongoing. To date, little is known about the etiology of irritable bowel syndrome; however, growing attention is drawn to the intestinal microbiota as a factor in the disease development. For this reason, researchers have conducted many studies on therapies that modulate the microbiota, among which probiotics, prebiotics, and synbiotics are widely studied. To date, most studies have examined probiotics; however, there are also several studies demonstrating the efficacy of prebiotics and synbiotics. The aim of this review was to summarize findings on the usefulness of probiotics, prebiotics, and synbiotics in the treatment of irritable bowel syndrome.


Assuntos
Disbiose/dietoterapia , Microbioma Gastrointestinal/efeitos dos fármacos , Síndrome do Intestino Irritável/dietoterapia , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Simbióticos/administração & dosagem , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/isolamento & purificação , Antibacterianos/efeitos adversos , Bacteroidetes/genética , Bacteroidetes/crescimento & desenvolvimento , Bacteroidetes/isolamento & purificação , Ensaios Clínicos como Assunto , Disbiose/etiologia , Disbiose/microbiologia , Disbiose/patologia , Firmicutes/genética , Firmicutes/crescimento & desenvolvimento , Firmicutes/isolamento & purificação , Fusobactérias/genética , Fusobactérias/crescimento & desenvolvimento , Fusobactérias/isolamento & purificação , Microbioma Gastrointestinal/genética , Humanos , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/patologia , Proteobactérias/genética , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/isolamento & purificação , Qualidade de Vida
17.
J Biotechnol ; 339: 81-92, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34364925

RESUMO

Pigments are compounds with highly diverse structures and wide uses, which production is increasing worldwide. An eco-friendly method of bioproduction is to use the ability of some microorganisms to ferment on renewable carbon sources. Wheat bran (WB) is a cheap and abundant lignocellulosic co-product of low recalcitrance to biological conversion. Microbial candidates with theoretical ability to degrade WB were first preselected using specific databases. The microorganisms were Ashbya gossypii (producing riboflavin), Chitinophaga pinensis (producing flexirubin), Chromobacterium vaccinii (violacein) and Gordonia alkanivorans (carotenoids). Growth was shown for each on minimal salt medium supplemented with WB at 5 g.L-1. Activities of the main enzymes consuming WB were measured, showing leucine amino-peptidase (up to 8.45 IU. mL-1) and ß-glucosidase activities (none to 6.44 IU. mL-1). This was coupled to a FTIR (Fourier Transform Infra-Red) study of the WB residues that showed main degradation of the WB protein fraction for C. pinensis, C. vaccinii and G. alkanivorans. Production of the pigments on WB was assessed for all the strains except Ashbya, with values of production reaching up to 1.47 mg.L-1. The polyphasic approach used in this study led to a proof of concept of pigment production from WB as a cheap carbon source.


Assuntos
Actinobacteria , Fibras na Dieta , Bacteroidetes , Chromobacterium
18.
Artigo em Inglês | MEDLINE | ID: mdl-34319223

RESUMO

Two Gram-stain-negative, non-motile, rod-shaped bacterial strains were isolated from the surfaces of rice roots. They were designated as strains 1303T and 1310. Their colonies were circular, entire, opaque, convex and yellow. They were chitinase- and catalase-positive, reduced nitrate and grew at 16-37 °C (optimum, 30 °C), pH 5.0-10.0 (optimum, pH 7.0) and 0-2.0% NaCl (optimum, 1.0 %). Based on the 16S rRNA gene sequence analysis, they were classified as members of the genus Chitinophaga. Results of phylogenetic and phylogenomic analyses indicated that they formed a cluster with Chitinophaga eiseniae YC6729T, Chitinophaga qingshengii JN246T, Chitinophaga varians 10-7 W-9003T and Chitinophaga fulva G-6-1-13T. When the genomic sequences of strains 1303T and 1310 were compared with their close relatives, the average nucleotide identity and digital DNA-DNA hybridization values were below the cut-off levels. Phosphatidylethanolamine was the major polar lipid. MK-7 was the major respiratory quinone. iso-C15 : 0, C16 : 1 ω5c, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c) were the predominant fatty acids. Differential characteristics between both strains and their close relatives were also observed. Based on the distinctions in genotypic, phenotypic and chemotypic features, strains 1303T and 1310 represent members of a novel species of the genus Chitinophaga, for which the name Chitinophaga oryzae sp. nov. is proposed. The type strain is 1303T (=KACC 22075T=TBRC 12926T).


Assuntos
Bacteroidetes/classificação , Oryza/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tailândia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-34292144

RESUMO

Two Gram-stain-negative, catalase-positive, oxidase-negative, rod-shaped, non-flagellated, non-spore-forming and non-motile strains (YJ13CT and H41T) were isolated from a mariculture fishpond in PR China. Comparisons based on 16S rRNA gene sequences indicated that YJ13CT and H41T shared 16S rRNA gene sequences similarities between 92.6 and 99.2 % with species of the genus Algoriphagus. YJ13CT only shared 93.8 % 16S rRNA gene sequence similarity with H41T. The reconstructed phylogenetic and phylogenomic trees indicated that YJ13CT and H41T clustered closely with species of the genus Algoriphagus. The calculated pairwise orthologous average nucleotide identity with usearch (OrthoANIu) values between strains YJ13CT and H41T and other related strains were all less than 79.5 %. The OrthoANIu value between YJ13CT and H41T was only 69.9 %. MK-7 was the predominant respiratory quinone of YJ13CT and H41T and their major cellular fatty acids contained iso-C15 : 0, C16 : 1 ω7c and C17 : 1 ω9c. The polar lipids profiles of YJ13CT and H41T consisted of phosphatidylethanolamine and several kinds of unidentified lipids. Combining the above descriptions, strains YJ13CT and H41T represent two distinct novel species of the genus Algoriphagus, for which the names Algoriphagus pacificus sp. nov. (type strain YJ13CT=GDMCC 1.2178T=KCTC 82450T) and Algoriphagus oliviformis sp. nov. (type strain H41T=GDMCC 1.2179T=KCTC 82451T) are proposed.


Assuntos
Aquicultura , Bacteroidetes/classificação , Filogenia , Lagoas/microbiologia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Curr Microbiol ; 78(8): 3334-3341, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34259886

RESUMO

Two novel Gram-stain-negative, non-motile, aerobic, rod-shaped, circular, convex, red-colored and UV-tolerant strains BT594T and BT646T were isolated from soil collected in Guri city (37° 36' 0″ N, 127° 9' 0″ E) and Gwangju city (37° 22' 0″ N, 127° 17' 0″ E), respectively, South Korea. 16S rDNA sequence analysis indicated that strains BT594T and BT646T belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes, kingdom Bacteria). The 16S rDNA gene sequence similarity between the two strains BT594T and BT646T was 96.2%. The strain BT594T was closely related to Hymenobacter psychrotolerans Tibet-IIU11T (97.0% 16S rDNA gene similarity) and Hymenobacter tibetensis XTM003T (96.3%). The strain BT646T was closely related to Hymenobacter psychrotolerans Tibet-IIU11T (98.6%), Hymenobacter kanuolensis T-3 T (96.8%) and Hymenobacter perfusus LMG 26000 T (96.7%). The two strains were found to have the same quinone system, with MK-7 as the major respiratory quinone. The major polar lipids of strains BT594T and BT646T were phosphatidylethanolamine (PE) and aminophospholipids (APL). The major cellular fatty acids of strain BT594T were anteiso-C15:0 (17.9%), iso-C15:0 (16.1%) and summed feature 3 (C16:1 ω6c / C16:1 ω7c) (10.0%). The major cellular fatty acids of strain BT646T were summed feature 3 (C16:1 ω6c / C16:1 ω7c) (18.3%), C16:0 (17.2%) and summed feature 4 (iso-C17:1 I / anteiso-C17:1 B) (14.5%). Based on the polyphasic analysis, strains BT594T and BT646T can be suggested as two novel bacterial species within the genus Hymenobacter and the proposed names are Hymenobacter guriensis and Hymenobacter duratus, respectively. The type strain of Hymenobacter guriensis is BT594T (= KCTC 21863 T = NBRC 114853 T) and the type strain of Hymenobacter duratus is BT646T (= KCTC 21915 T = NBRC 114854 T).


Assuntos
Cytophagaceae , Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes , Composição de Bases , Cytophagaceae/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Microbiologia do Solo , Tibet
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