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Different Types of Dietary Fibers Trigger Specific Alterations in Composition and Predicted Functions of Colonic Bacterial Communities in BALB/c MiceLuo, Yuheng, Zhang, Ling, Li, Hua, Smidt, Hauke, Wright, Andre-Denis G., Zhang, Keying, Ding, Xuemei, Zeng, Qiufeng, Bai, Shiping, Wang, Jianping, Li, Jian, Zheng, Ping, Tian, Gang, Cai, Jingyi, Chen, Daiwen 30 May 2017 (has links)
Soluble dietary fibers (SDF) are fermented more than insoluble dietary fibers (IDF), but their effect on colonic bacterial community structure and function remains unclear. Thus, bacterial community composition and function in the colon of BALB/c mice (n = 7) fed with a high level (approximately 20%) of typical SDF, oat-derived beta-glucan (G), microcrystalline cellulose (M) as IDF, or their mixture (GM), were compared. Mice in group G showed a lowest average feed intake (p < 0.05) but no change on the average body weight gain (p > 0.05) compared to other groups, which may be associated with the highest concentration of colonic propionate (p < 0.05) in these mice. The bacterial alpha-diversity of group G was significantly lower than other groups (p < 0.01). In group G, the relative abundance of bacteria belonging to the phylum Bacteroidetes was significantly increased, whereas bacteria from the phylum Firmicutes were significantly decreased (p < 0.01). The core bacteria for different treatments showed distinct differences. Bacteroides, Dehalobacterium, and Prevotella, including known acetogens and carbohydrate fermenting organisms, were significantly increased in relative abundance in group G. In contrast, Adlercreutzia, Odoribacter, and Coprococcus were significantly more abundant in group M, whereas Oscillospira, Desulfovibrio, and Ruminoccaceae, typical hydrogenotrophs equipped with multiple carbohydrate active enzymes, were remarkably enriched in group GM (p < 0.05). The relative abundance of bacteria from the three classes of Proteobacteria, Betaproteobacteria, Gammaproteobacteria (including Enterobacteriaceae) and Deltaproteobacteria, were significantly more abundant in group G, indicating a higher ratio of conditional pathogenic bacteria in mice fed dietary beta-glucan in current study. The predicted colonic microbial function showed an enrichment of "Energy metabolism" and "Carbohydrate metabolism" pathways in mice from group G and M, suggesting that the altered bacterial community in the colon of mice with the two dietary fibers probably resulted in a more efficient degradation of dietary polysaccharides. Our result suggests that the influence of dietary beta-glucan (SDF) on colonic bacterial community of mice was more extensively than MCC (IDF). Co-supplementation of the two fibers may help to increase the bacterial diversity and reduce the conditional pathogens in the colon of mice.
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Genetic Characterization of the Gut Microbiome of Hajj PilgrimsBeaudoin, Christopher 05 1900 (has links)
Hajj, the annual Islamic pilgrimage to Makkah, Saudi Arabia, is a unique mass gathering event that brings more than 2 million individuals from around the world. Several public health considerations, such as the spread of infectious diseases, must be taken into account with this large temporary influx of people. Gastrointestinal diseases, such as diarrhea, are common at Hajj, yet little is known about the etiology. The human gut microbiome, collection of organisms residing within the intestinal tract, has been under intense study recently, since next generation DNA sequencing technologies allow for extensive surveying of genetic material found in complex biological samples, such as those containing many different organisms. Thus, using 16S rRNA and metagenomic shotgun sequencing, we have characterized the gut microbiome of over 612 pilgrims with and without diarrhea. Several metadata factors, such as hospitalization and different comorbidities, were found to have significant effects on the overall gut microbiome composition. Metagenomic shotgun sequencing efforts revealed the presence of antimicrobial resistance genes originating from disparate regions from around the world. This study provides a snapshot of information concerning the health status of the gut microbiome of Hajj pilgrims and provides more context to the investigation of how to best prepare for mass gathering events.
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Vliv komerčních probiotických preparátů na složení střevního mikrobiomu člověka / Influence of commercial probiotic preparations on human intestinal microbiome compositionBalatka, Štěpán January 2021 (has links)
The intestinal microflora is an extensive ecosystem of microorganisms that consists of symbiotic and pathogenic species. The microflora is responsible for many important functions in the human body. An unquestionable function is that it affects the health state of the host. The higher the biodiversity, the greater the benefit for the host. However, it is necessary to point out that this should not include a high diversity of pathogenic bacterial species. There are many "beneficial" species, especially from the Bifidobacterium and Lactobacillus families. In recent decades, the popularity of supplementing these "beneficial" species with various supplementary diets (e.g. probiotics) has been growing a lot. The presented diploma thesis deals with pilot studies of liquid commercial probiotic preparations from American companies Ascended Health (not available on the Czech market) and their effects on the human microbiome. The study involved 9 volunteers who provided 70 fecal samples before, during, and after use of the studied products. Two methods were used to determine the biodiversity of intestinal bacterial species. Both are based on the identification by bacterial DNA that encodes gene 16S rRNA. The first method uses PCR-DGGE technique and then identification by Sanger sequencing. The second method...
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Klasifikace bakterií pomocí markerových genů / Bacteria Classification Based on Marker GenesPelantová, Lucie January 2020 (has links)
The aim of this work is proposal of new method for bacteria classification based on sequences of marker genes. For this purpose was chosen 10 marker genes. Resulting MultiGene classifier processes data set by dividing it in several groups and choosing gene for each group which can distinguish this group with best results. This work describes implementation of MultiGene classifier and its results in comparison with other bacteria classifiers and with classification based entirely on gene 16S rRNA.
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Izolace DNA ze sýrů pro použití v polymerázové řetězové reakci / DNA extraction from cheeses for polymerase chain reaction analysisMohelský, Tomáš January 2013 (has links)
This work was focused on DNA isolation from cheeses for the use in polymerase chain reaction. First, there was optimised the procedure of homogenisation of different types of cheeses from commercial sources, cell lysis and DNA isolation. DNA was isolated using magnetic microspheres and phenol extraction. It was shown that the DNA was amplified in PCR for domain Bacteria after dilution. Next, there was optimised the procedure of DNA isolation from fresh cheeses and from contaminated fresh cheeses and their pickles. DNA from all samples was amplified in PCR. The presence of DNA of domain Bacteria and yeast DNA was demonstrated. In the last part of the work, there were optimised the preparation of PCR mixtures and bacterial DNA amplification in PCR with primers with clamp (F357-GC and R518). Synthetized PCR products were analysed using DGGE. It was shown that amplicons of DNA isolated from cheeses and pickles differ in positions and numbers. Larger number of bands of different intensities was detected after amplification of DNA isolated from contaminated pickles.
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Genetická a morfologická variabilita evropského rodu Cochlodina (Mollusca: Gastropoda: Clausiliidae) se zaměřením na druh C. laminata (Montagu, 1803) / Genetic and Morphological Variability of the European Genus Cochlodina (Mollusca: Gastropoda: Clausiliidae) with Focus on Species C. laminata (Montagu, 1803)Szalontayová, Veronika January 2013 (has links)
This thesis focuses on the genetical and morphological diversity of plaited door snail (Cochlodina laminata). While small distribution ranges are typical for most species belonging to genus Cochlodina, the distribution range of C. laminata covers most of the European continent, except for its coolest and warmest parts. It has been previously suggested that this species might in fact be a complex of several species and large genetical as well as morphological diversity has been mentioned - however, yet undescribed - in previous studies. Sequences of two mitochondrial genes were used (16S rDNA, COI) and thirteen morphological characteritics have been assessed to investigate this diversity. I discovered that the current concept of C. laminata as a species is not in accordance with the discovered genetical nor morphological variability. The original species C. laminata/C. dubiosa form a common species complex and also interpretation of C. fimbriata will need to be assessed in more detail in the future. Other Central European species are valid species.
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Isolation and characterization of bacterial endophytes for growth promotion of Phaseolus vulgaris under salinity stressThompson, Biosha January 2020 (has links)
>Magister Scientiae - MSc / As the global human population grows, so does the demand for faster food production rates. Owing to this, agricultural practices have had to expand and move into semi-arid and arid regions, too, where frequent irrigation is essential. However, irrigated ground water contains many salt ions (mainly Na+ and Cl-) which contribute to soil salinization on croplands. Soil salinity negatively impacts crop growth and yield and thus, strategies for the alleviation of salt stress on crop plants have had to be developed. This study assessed the use of plant growth promoting bacteria (PGPB). The aim of this study was to isolate, identify and characterize bacterial endophytes isolated from the halophyte, Arctotheca calendula. Endophytes were identified using 16S rDNA and were screened for plant growth promoting properties including nitrogen fixation, phosphate and zinc solubilization, siderophore, ammonia and indole-3-acetic acid (IAA) when exposed to 0 mM, 300 mM and 600 mM NaCl. The endophytes had been identified as Erwinia persicina NBRC 102418T, Bacillus marisflavi JCM 11544T, Ochrobactrum rhizosphaerae PR17T, Microbacterium gubbeenense DSM 15944T and Bacillus zhangzhouensis DW5-4T and all of which had demonstrated some plant growth promoting characteristics. Thereafter, we aimed to demonstrate plant growth promotion of P. vulgaris cv. Star 2000 inoculated with PGPB under salinity stress. P. vulgaris cv. Star 2000 seeds were inoculated with the PGPB and exposed to 0 mM and 100 mM NaCl. Post-harvest, plants were assessed for their dry mass, cell death, superoxide concentration and nutrient content. It was discovered that salinity negatively impacted P. vulgaris cv. Star 2000’s dry mass, NaCl-induced cell death, and differentially influenced superoxide concentration, nutrient uptake and content of the leaf and root material in the inoculated and control treatments. However, the isolated PGPB had been able to mitigate the negative effects of soil salinity on P. vulgaris cv. Star 2000.
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Towards spatial host-microbiome profilingLötstedt, Britta January 2021 (has links)
Sequencing technologies and applications have pushed the limits and enabled novel studies of biological mechanisms, evolutionary relationships and communication networks between cells. The technical developments leading to single cell RNA-sequencing have enabled detection of rare cell populations while spatial resolution added insights into larger biological environments, like tissues and organs. Massively parallel sequencing has paved the way for integrated high-throughput analyses including that of studying gene expression, protein expression and mapping of microbial communities. This thesis starts with an introduction describing the technical and biological advancements made in recent years with focus on spatially resolved approaches. Then, a summary of recent accomplishments is presented, which enabled ongoing work in a novel field of spatial hostmicrobiome profiling. Lastly, the concluding remarks include both a future perspective and a short reflection on the current developments in the spatial multi-omics field. 16S sequencing is often used for taxonomic classification of bacteria. In Paper I, this sequencing technique was used to study the aerodigestive microbiome in pediatric lung transplant recipients. Many of these patients regretfully reject the organ after transplant, but the underlying cause is, in many cases, unknown. In this paper, multiple factors influencing rejection were examined including that of the aerodigestive microbiome. Pediatric lung transplant recipients often suffer from gastrointestinal dysmotility and the focus of this study was also to analyze changes in the microbiome in relation to irregular gastric muscle movements. The results showed that lung transplant recipients had, in general, lower microbial diversity in the gastric fluid and throat and also that the microbial overlap between lung and gastric sampling sites was significantly less in transplant recipients compared to controls. In addition, gastrointestinal dysmotility was shown to influence the gastric microbiome in lung transplant recipients, but, given the small sample size available in this study, the correlation to patient outcome could not be examined. Integrated analysis of the transcriptome and the antibody-based proteome in the same tissue section was enabled using the method developed in Paper II. Spatial Multi- Omics (SM-Omics) uses a barcoded glass array to capture mRNA and antibody-based expression of selected proteins in the same section. The antibody-based profiling of the tissue section was enabled by either immunofluorescence or DNA-barcoded antibodies that were then decoded by sequencing. The protocol was scaled-up using an automated liquidhandling system. Using this method, simultaneous profiling of the transcriptome and multiplexed protein values was determined in both the mouse brain cortex and mouse spleen. Results showed a high correlation in spatial pattern between gene expression and antibody measurements, independently of the antibody labelling technique. SM-Omics generates a high-plex multi-omics characterization of the tissue in a high throughput manner while exhibiting low technical variation. / Tekniker och applikationer som använder sekvensering har flyttat fram gränsernaoch tillåtit nya undersökningar av biologiska mekanismer, evolutionära släktskap ochkommunikationsnätverk mellan celler. De tekniska utvecklingarna som har lett fram tillRNA-sekvensering av enskilda celler har möjliggjort upptäckten av sällsynta cellpopulationer medan den rumsliga upplösningen har inneburit en ökad förståelse av störrebiologiska miljöer, såsom vävnader och organ. Massively parallel sequencing har banat vägför integrerade analyser med hög kapacitet, vilket inkluderar analys av genuttryck,proteinuttryck och kartläggning av bakteriella samhällen. Den här avhandlingen börjar meden introduktion som beskriver tekniska och biologiska framsteg som gjorts de senaste åren,med fokus på den rumsliga upplösningen. Sedan följer en summering av de senasteprestationerna som har möjliggjort det pågående arbetet i ett nytt fält som avhandlarrumslig profilering av bakterien och dess värd. Slutligen innehåller slutordet både ettframtida perspektiv samt en kort reflektion av den nuvarande utvecklingen inom fälten förrumslig mång-omik. 16S-sekvensering används ofta för att taxonomiskt klassificera bakterier. Dennasekvenseringsteknik användes i artikel I för att studera mikrobiomet i luft- ochmatspjälkningskanalen hos barn med transplanterad lunga. Dessvärre är det vanligt medavstötning av lungan efter transplantationen hos många av dessa patienter, men denunderliggande orsaken till avstötningen är, i många fall, okänd. I denna studie undersöktesflertalet faktorer, inklusive mikrobiomet i luft- och matspjälkningskanalen, som kan tänkaspåverka bortstötningen. Barn med transplanterad lunga lider ofta av störningar i magtarmkanalens rörelser och artikelns fokus var därmed även att analysera förändringar imikrobiomet i relation till dessa avvikande rörelser i mag-tarmkanalen. Resultatet visade attpatienter med transplanterad lunga generellt hade lägre bakteriell mångfald i magsaft ochhals, samt att det bakteriella överlappet mellan lunga och magsaft var signifikant mindre ipatienter med transplanterad lunga jämfört med kontrollerna. För övrigt visade det sig attstörningar i mag-tarmkanalens rörelser påverkade magsaftens mikrobiom hos patientermed transplanterad lunga, men på grund av studiens storlek på urvalet, kunde det inteundersökas hur detta korrelerade till utfallet hos patienterna. Integrerad analys av transkriptomet och antikroppsbaserad analys av proteomet isamma vävnadssnitt har möjliggjorts genom metoden som utvecklats i artikel II. SpatialMulti-Omics (SM-Omics) använder ett avkodningsbart mönster av korta DNA-segment påen glasyta för att fånga mRNA och antikroppsbaserat uttryck av utvalda proteiner frånsamma vävnadssnitt. Den antikroppsbaserade profileringen av vävnadssnittet uppnåddesgenom antingen immunofluorescens eller antikroppar märkta med DNA-segment somkunde avkodas genom sekvensering. Protokollet skalades upp genom ett automatiseratsystem för att behandla vätskor. Genom användning av denna metod kunde simultanprofilering av transkriptomet och flertalet proteiner uppnås i både hjärnbarken och mjältenhos en mus. Resultaten visade en hög korrelation i det rumsliga mönstret mellangenuttrycket och de antikroppsbaserade mätningarna, oberoende av hur antikropparnahade märkts. SM-Omics genererar en storskalig karaktärisering av vävnaden av flera omikermed hög kapacitet samtidigt som den har låg teknisk variation. / <p>QC 2021-02-02</p>
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Molecular and Morphological Evolution of the Amphipod Radiation of Lake BaikalMacdonald, Kenneth S., Yampolsky, Lev, Duffy, J. Emmett 01 January 2005 (has links)
Lake Baikal, in Siberia, Russia, contains the highest biodiversity of any extant lake, including an impressive radiation of gammaroidean amphipods that are often cited as a classic case of adaptive radiation. However, relationships among Baikal's amphipods remain poorly understood. The phylogenetic history of 32 Lake Baikal amphipod species, representing most major lineages of the endemic fauna, was examined using three genes (COI, 16S rRNA, and 18S rRNA), and 152 morphological characters. Results support monophyly of the largest and most diverse of the Baikalian families, the Acanthogammaridae. Analyses suggest that a second Baikalian family, the fossorial Micruropodidae, is paraphyletic and composed of two divergent clades, one of which includes Macrohectopus branickii, a morphologically specialized pelagic planktivore traditionally assigned its own family. The extreme morphological and ecological divergence of Macrohectopus from its close genetic relatives, and conversely, the large genetic distances among other morphologically similar micruropodids, suggest that morphological and molecular evolution have often been uncoupled during the radiation of Baikal's amphipods. This study suggests that the amphipod fauna of Lake Baikal is polyphyletic; originating from two independent invasions of the lake.
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Utveckling och validering av en qPCR metod för detektion av DNA från tarmbakterier i blod/plasmaJohansson, Kajsa January 2020 (has links)
Enligt "Leaky gut”-hypotesen är ökad translokation av gramnegativa bakterier genom tarmslemhinnan förknippad med neuroimmuna störningar. Denna ökning av permeabiliteten i tarmslemhinnan kan orsakas av störning i tarmfloran efter antibiotikabruk eller sjukdom, vilket kan leda till inflammatoriska processer. Inflammation har sedan tidigare blivit förknippad med allvarlig depressiv störning och självmordsbeteende. Studiens syfte var att utveckla och validera en qPCR-baserad metod för att kunna detektera DNA från tarmbakterier i blod/plasma, som ett tecken på translokering av bakterier. Två primerpar för amplifiering av 16S rDNA utreddes genom observation av PCR-reaktioner med humant och bakteriellt DNA. Det mest optimala primerparets PCR effektiviteten och linjäriteten testades. Metodens funktion kontrollerades sedan med helblod och plasma med tillsats av exogent DNA från E.coli. Den utvecklade qPCR metoden detekterar bakterie DNA i prov med 10 kopior/µl, vilket gör den tillräckligt känslig för detektion av tarmbakterier i blod. / According to the "Leaky gut" hypothesis, increased translocation of gram-negative bacteria through the intestinal mucosa is associated with neuroimmune disorders. The increase of permeability of the intestinal mucosa may be caused by disturbance of the intestinal flora after antibiotic use or disease, which can lead to inflammatory processes. Inflammation has previously been associated with major depressive disorder and suicidal behavior. The purpose of the study was to develop and validate a qPCR-based method for detecting DNA from intestinal bacteria in blod/plasma, as a sign of decreased mucosal integrity. Two different primer pairs, targeting 16S rDNA, were investigated by observing their PCR reactivity with human and bacterial DNA. PCR efficiency and linearity were tested on the most optimal primer pair. The function of the method was then verified with whole blood and plasma with the addition of exogenous DNA from E.coli. The developed qPCR method detects bacterial DNA in samples at 10 copies/µl, making it sufficiently sensitive for detection of intestinal bacterial DNA in blood.
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