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Identificação bacteriana por derivação de ácidos graxos extraídos de células íntegras / Bacterial identification by fatty acid derivation extracted from whole cellsFábio Luiz Camacho Pacheco 16 June 2009 (has links)
As salas limpas são amplamente empregadas em indústrias farmacêuticas destinadas a fabricar medicamentos e dispositivos estéreis. Nós empregamos coloração de Gram e cromatografia gasosa de ésteres metílicos de ácidos graxos extraídos de células íntegras de microrganismos ambientais para caracterizar e identificar bactérias isoladas em 50 salas limpas diferentes projetadas para a fabricação de medicamentos estéreis e para fornecer um perfil de ácidos graxos das espécies mais comuns de bactérias isoladas. Uma análise estatística nos permitiu corroborar estudos anteriores e confirmar que cocos Gram positivos é o grupo mais relevante de microrganismos presentes nas salas limpas avaliadas. A espécie predominante é Micrococcus luteus, isolada de salas classe B e de pessoal, seguida de Staphylococcus cohnii em classe C, Bacillus subtilis em classe A e Staphylococcus hominis em classe D. Os perfis de ácidos graxos destas bactérias são, na maioria, consistentes com as bibliotecas padrão. Nós também tentamos estabelecer uma correlação entre a estação do ano e o nível de contaminação, embora a análise de variância tenha mostrado que não há diferença significativa entre o nível de contaminação no decorrer das estações. Além do mais, análises repetidas com um aumento gradual de massa celular nos permitiram concluir que a quantidade ótima de material celular necessário para extração de ácidos graxos varia com a espécie de bactéria. Finalmente, um estudo comparativo de algumas bactérias incubadas em diferentes temperaturas confirmou que o perfil de ácidos graxos é altamente influenciado pela temperatura. Portanto, nós acreditamos que este trabalho possa contribuir para identificar e compreender a comunidade bacteriana de algumas salas limpas farmacêuticas. / Clean rooms are largely employed in pharmaceutical companies whose purpose is to produce sterile drugs and devices. We employed Gram staining and gas chromatography of fatty acid methyl esters extracted from whole cells of environmental isolates to characterize and identify bacteria isolated in each of 50 different clean rooms designed for the manufacturing of sterile medicinal products and to provide a fatty acid profile of the most common species of isolated bacteria. Statistical analysis allowed us to corroborate previous studies and confirm that Gram-positive cocci are the most relevant group of microorganisms inside the studied clean rooms. The predominant species is Micrococcus luteus, isolated from Grade B zones and from personnel, followed by Staphylococcus cohnii in Grade C, Bacillus subtilis in Grade A and S. hominis in Grade D. Fatty acid profiles of these bacteria are, to a great extent, consistent with standard libraries. We also attempted to establish a correlation between season and level of contamination, although variance analysis showed that there is no significant difference on the level of contamination throughout seasons. Furthermore, repeated analysis with a gradual increase in cell mass allowed us to conclude that the optimal amount of cell material depends on the species of the bacteria studied. Finally, a comparative study with some bacteria incubated in different temperatures confirmed that fatty acid profile is highly influenced by temperature. Therefore, we believe that this work can contribute to identify and understand the bacterial community of some pharmaceutical clean rooms.
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Microbial Community Richness Distinguishes Shark Species Microbiomes in South FloridaKarns, Rachael Cassandra 28 July 2017 (has links)
The microbiome (microbial community) of individuals is crucial when characterizing and understanding processes that are required for organism function and survival. Microbial organisms, which make up an individual’s microbiome, can be linked to disease or function of the host organism. In humans, individuals differ substantially in their microbiome compositions in various areas of the body. The cause of much of the composition diversity is yet unexplained, however, it is speculated that habitat, diet, and early exposure to microbes could be altering the microbiomes of individuals (Human Microbiome Project Consortium, 2012b, 2012a). To date, only one study has reported on microbiome characterization in a shark (Doane et al., 2017; skin microbiome of the common thresher shark). A comparative characterization of microbiomes sampled from different shark species and anatomical locations will allow an understanding of the differences in microbiomes that may be explained by variance in shark habitat and diet. Florida leads as shark bite capitol of the world, with 778 unprovoked bites recorded since 1837, or 4-5 average bites per year. With only a few bites a year, there is not a lot of opportunities to study these bites. What can be studied, however, is how the microbial environment in shark’s teeth is composed. To understand overall microbiome composition, and if microbiomes are distinct from the environment, or specific by species or anatomical location (henceforth location), we characterized microbiomes from the teeth, gill, skin, and cloacal microbiomes of 8 shark species in south Florida (nurse, lemon, sandbar, Caribbean reef, Atlantic sharpnose, blacktip, bull, and tiger) using high throughput DNA sequencing of the 16S rRNA gene V4 region. There was a significant difference in microbial community richness among species, sample location, but not the interaction between species and location. Microbial diversity by location was significantly different for both the Shannon index and Inverse Simpson index. Samples examined by species had no significant difference in microbial community diversity overall for both Shannon and Inverse Simpson indexes. Microbial community diversity of samples by location and species combined significantly differed when submitted to an analysis of variance with the Shannon index, but not the Inverse Simpson index. Teeth microbial communities showed the most diversity based on both Shannon and Inverse Simpson indices. Teeth microbiomes are distinct but also share taxa with the water they inhabit, including potentially pathogenic genera such as Streptococcus (8.0% ± 9.0%) and Haemophilus (2.9% ± 3.3%) in the Caribbean reef shark. The lemon shark teeth hosted Vibrio (10.8% ± 26.0%) and the Corynebacterium genus (1.6%±5.1%). The Vibrio genus (2.8% ± 6.34%), Salmonella enterica (2.6% ± 6.4%), and the genus Kordia (3.1% ± 6.0%) are found in the nurse shark teeth microbial community. Strikingly, the Vibrio genus was represented in the sandbar shark (54.0% ± 46.0%) and tiger shark (5.8% ±12.3%) teeth microbiomes. One OTU related to traditionally non-pathogenic family Phyllobacteriaceae appear to be driving up to 32% of variance in teeth microbiome diversity. We conclude that south Florida sharks host distinct microbiomes from the surrounding environment and vary among species due to differences in microbial community richness. Future work should focus on bacteria found in shark teeth to determine if those present are pathogenic and could provide insights to bite treatment.
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Investigating the Driving Mechanisms Behind Differences in Bleaching and Disease Susceptibility Between Two Scleractinian Corals, Pseudodiploria Strigosa and Diploria LabyrinthiformisPratte, Zoe A 15 June 2015 (has links)
Disease and bleaching are two conditions which commonly lead to coral death. Among coral species, susceptibility to disease and bleaching is variable, and Pseudodiploria strigosa tends to be diseased more than Diploria labyrinthiformis, while D. labyrinthiformis bleaches more readily. The focus of this dissertation was to investigate and compare multiple components of these two coral species, and identify how they may relate to disease and bleaching resistance. Compenetnts examined included the surface mucopolysacharide layer (SML) thickness, gene expression, microbial associates, and a white plague aquarium study. The SML thickness decresased with increasing temperature regardless of coral species, indicating that SML thickness does not likely play a role in differences between susceptablities of these two coral species. However, Diploria labyrinthiformis had a lower mortality rate at 31°C, had fewer differentially expressed genes assossiated with stress, and upregulated genes associated with innate immunity in the summer, all of which may contribute to its relative disease resistance. The bacterial associates of each coral species were also monitored. Differences between the two coral species were primarily caused by Clostridia, Gammaproteobacteria, and rare species which may contribute to the relatively higher disease susceptibility of P. strigosa. Lastly, an aquarium study suggested that a potential pathogen of the Roseobacter clade infects both D. labyrinthiformis and P. strigosa, and might be transmitted by the Cryptochiridae gall crab, indicating that potential disease vectors associated with these two coral species may also play a role in disease resistance and resilience.
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Biogeographical Patterns of Soil Microbial Communities: Ecological, Structural, and Functional Diversity and their Application to Soil ProvenanceDamaso, Natalie 28 October 2016 (has links)
The current ecological hypothesis states that the soil type (e.g., chemical and physical properties) determines which microbes occupy a particular soil and provides the foundation for soil provenance studies. As human profiles are used to determine a match between evidence from a crime scene and a suspect, a soil microbial profile can be used to determine a match between soil found on the suspect’s shoes or clothing to the soil at a crime scene. However, for a robust tool to be applied in forensic application, an understanding of the uncertainty associated with any comparisons and the parameters that can significantly influence variability in profiles needs to be determined. This study attempted to address some of the most obvious uncertainties of soil provenance applications such as spatial variability, temporal variability, and marker selection (i.e., taxa discrimination). Pattern analysis was used to validate the ecological theories driving the soil microbial biogeography. Elucidating soil microbial communities’ spatial and temporal variability is critical to improve our understanding of the factors regulating their structure and function. Microbial profiling and bioinformatics analyses of the soil community provided a rapid method for soil provenance that can be informative, easier to perform, and more cost effective than approaches using traditional physico-chemical data. This study also showed that stable profiles may allow comparison between evidence and a possible crime scene despite the time lapse (4 years) between sample collections, however, this is dependent on the analysis method, site, vegetation, and level of disturbance. Marker selection was also an important consideration for profiling. Even though Fungi look promising for single taxon soil discrimination, the additional markers can help discriminate between a wide variety of soil types. As in human identification, the more DNA markers queried the greater the discrimination power. Lastly, this study illustrated a novel method to query the iron relating genes and ability to design a novel marker that can easily be used to profile the functional diversity of a soil community to enhance soil classification. Overall this research demonstrated the potential and effectiveness of using microbial DNA from soil, not just for comparison, but also for intelligence gathering to pinpoint the geographic origin of the soil.
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Comparison of Synthetic Versus Organic Herbicides/Insecticides on Arbuscular Mycorrhizal Fungi in Abelmoschus esculentusFreidenreich, Ariel 14 June 2016 (has links)
Arbuscular mycorrhizal fungi (AMF) play a crucial role in improving the growth of a vast majority of plants. Past researchers have discovered that agricultural practices have a significant negative effect on the diversity of AMF. Arbuscular mycorrhizal fungi are reported to enhance plant nutrient uptake, stress tolerance, and soil aggregate formation which are key aspects of productive low-input farming. The objective of this study was to investigate the effects of four pesticides on the ability of AMF to colonize the roots of okra plants (Abelmoschus esculentus). The pesticides being tested include two synthetic chemicals (glyphosate and carbaryl) and two organic chemicals (neem oil and citrus oil). The tested parameters included crop yield, plant biomass, leaf matter CNP, and the percentage of mycorrhizal colonization in roots. The results of this study show that the organic chemicals had no significant effect on AMF colonization while the synthetic chemicals did have somewhat of a negative effect on colonization.
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Acclimatization of the Tropical Reef Coral Acropora millepora to Hyperthermal StressBellantuono, Anthony John 05 September 2013 (has links)
The demise of reef-building corals potentially lies on the horizon, given ongoing climate change amid other anthropogenic environmental stressors. If corals cannot acclimatize or adapt to changing conditions, dramatic declines in the extent and health of the living reefs are expected within the next half century. The primary and proximal global threat to corals is climate change. Reef-building corals are dependent upon a nutritional symbiosis with photosynthetic dinoflagellates belonging to the group Symbiodinium. The symbiosis between the cnidarian host and algal partner is a stress-sensitive relationship; temperatures just 1°C above normal thermal maxima can result in the breakdown of the symbiosis, resulting in coral bleaching (the loss of Symbiodinium and/or associated photopigments) and ultimately, colony death. As ocean temperatures continue to rise, corals will either acclimatize or adapt to changing conditions, or will perish. By experimentally preconditioning the coral Acropora millepora via sublethal heat treatment, the coral acquired thermal tolerance, resisting bleaching during subsequent hyperthermal stress. The complex nature of the coral holobiont translates to multiple possible explanations for acclimatization: acquired thermal tolerance could potentially originate from the host itself, the Symbiodinium, or from the bacterial community associated with the coral. By examining the type of in hospite Symbiodinium and the bacterial community prior acclimation and after thermal challenge, it is shown that short-term acclimatization is not due to a distinct change in the dinoflagellate or prokaryote community. Though the microbial partnerships remain without considerable flux in preconditioned corals, the host transcriptome is dynamic. One dominant pattern was the apparent tuning of gene expression observed between preconditioned and non-preconditioned treatments, showing a modulated transcriptomic response to stress. Additionally several genes were upregulated in association with thermal tolerance, including antiapoptotic genes, lectins, and oxidative stress response genes. Upstream of two of these thermal tolerance genes, inhibitor of NFκB and mannose-binding lectin, DNA polymorphisms were identified which vary significantly between the northern and southern Great Barrier Reef. The impact of these mutations in putative promoter regions remains to be seen, but variation across thermally-disparate geography serves to generate hypotheses regarding the role of regulatory element evolution in a coral adaptation context.
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Microbial Functional Diversity and the Associated Biogeochemical Interactions Across Miami-Dade County, Florida SoilsKushwaha, Priyanka 02 November 2016 (has links)
Decomposition of soil organic matter by microbial processes results in carbon sequestration within soils and/or carbon loss via atmospheric emission of carbon dioxide and methane. Natural as well as anthropogenic factors have been documented to impact soil microbial diversity and the associated biogeochemical functions. The soil microbial communities co-inhabiting Miami-Dade County soils, Florida are under threat because of the ongoing restoration efforts in the adjoining Florida Everglades Parks, predicted climatic changes such as sea-level rise and high rainfall, as well as urbanization. Therefore, an improved understanding of the current microbial functional communities is essential to better assess the impact of soil communities when anthropogenic or climatic disturbances occur. The objectives of the current study were to characterize the biodiversity and distribution of: a) cellulose degrading microbial community, and b) methanogenic guilds responsible for producing the gas methane, across four different Miami-Dade County, Florida soil types using the high throughput technique of GeoChip 5.0 functional microarray. In addition, the influence of vegetation cover, organic content, soil moisture content, pH, and soil texture in shaping the soil functional microbial community was also investigated. The function of cellulose degradation was distributed across wide range of taxonomic lineages with the majority belonging to the bacterial groups of Actinobacteria, Firmicutes, Alphaproteobacteria, and Gammaproteobacteria, whereas Ascomycota and Basidiomycota were the only detected fungal phyla. The cellulolytic bacterial community correlated more with the vegetation cover while fungal groups showed influence of moisture and organic content as well as percent silt. Six out of the seven methanogenic orders, with the greatest numbers found in the Methanomicrobiales, Methanosarcinales, and Methanomassiliicoccales, were identified across all four soil types of Miami-Dade. The abundance of the mcrA gene sequences was significantly greater with respect to soil moisture content. Additionally, the recently classified order Methanomassiliicoccales was identified across all four soils, including soils with lower moisture content not thought to provide ideal redox conditions to support methanogens. The greater number of correlation network interactions amongst the methanogenic guilds in the Florida Everglades wetlands versus the urbanized Miami-Dade County soils depicted the impact of the historical drainage of the Florida Everglades on the methanogenic community. Overall, the current study characterized the biodiversity of cellulolytic and methanogenic organisms across dry and saturated soils of Miami-Dade County and demonstrated that microbial guilds were functionally redundant and were influenced to some extent by the soil abiotic factors. Also, results from network analyses provide a platform to assess the future impacts of disturbances on the microbial community.
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Bacteriostatic Effects of Sucralose on Environmental BacteriaOmran, Arthur Phillip, Jr. 01 January 2013 (has links)
Sucralose is a zero calorie sweetener developed and manufactured by Tate and Lyle Sweetener Company in the 1980’s. They sell the sweetener compounded with maltodextrin and dextrose under the brand name Splenda®. Sucralose was developed as a low cost artificial sweetener that is non-metabolizable in humans and can withstand changes in pH and temperature. It is not degraded by the waste water treatment process. Since the molecule can withstand heat, acidification and microbial degradation it is accumulating in the environment, and has been found in waste water, estuaries, rivers and the Gulf Stream. The highest concentration of environmental sucralose detected to date is 300 ng/L (Torres et al., 2009). Our lab has isolated six bacterial species from areas that may have been exposed to sucralose, given that sucralose has been detected throughout the aquatic environment (Mead et al., 2009). These isolates were cultured in the presence of sucralose looking for potential sucralose metabolism or growth acceleration. Sucralose was found to be nonnutritive, and we found bacteriostatic effects on all six isolates. This inhibition was directly proportional to the concentration of sucralose exposure. The amount of the growth inhibition appears to be species specific. The bacteriostatic effect may be due to a decrease in sucrose uptake by bacteria exposed to sucralose. We have determined that sucralose inhibits invertase and sucrose permease. These enzymes cannot catalyze hydrolysis or be effective in transmembrane transport of the sugar substitute. As sucralose builds up in the environment we must consider it a contaminant due to its bacteriostatic effect. Sucralose may also destabilize or shift the compositions of the bacterial communities in microenvironments such as the mammalian gut.
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Metabolic Modeling of Cystic Fibrosis Airway Microbiota from Patient SamplesVyas, Arsh 20 October 2021 (has links)
Cystic Fibrosis (CF) is a genetic disorder, found with higher prevalence in the Caucasian population, affecting > 30,000 individuals in the United States and > 70,000 worldwide. Due to the astoundingly high rate of mortality among CF patients being attributed to respiratory failure brought on by chronic bacterial infections and subsequent airway inflammation, there has been a lot of focus on systematically analyzing CF lung airway communities. While it is observed traditionally that Pseudomonas aeruginosa is the most threatening and persistent CF colonizer due to high antibiotic resistance, recent studies have elicited the roles of other pathogens and it has been widely accepted the CF lung airway consists of a complex codependent community of bacteria, viruses, and fungi.
To elucidate the interplay among the members of this community, within the constraint of lung uptake regime, I developed a community metabolic network model comprising of >380 metabolites obtained after modeling 39 most abundant bacterial genera across 279 sputum specimens collected from 79 individuals over 10 years from a study by LiPuma et. al. by 16S rRNA gene sequencing, accounting for >89% of reads across samples. The community metabolic model was contrasted with the 16S relative abundance data through standard data mining techniques employed for the analysis of multidimensional data. I further attempted to quantitatively analyze and elucidate the correlations among patient lung function, disease progression, community diversity, microbial compositions, and metabolic capabilities by standard classical hypothesis testing methods.
Comparison through linear dimensionality reduction (PCA) of the 16S data and the model data revealed slightly higher variance explained by the model, indicating presence of relatively smaller number of metabolite-based than the 16S-based polymicrobial communities. A deeper analysis elucidated both the phenomena, consolidation of compositionally different communities due to metabolic closeness, as well as splitting of other communities into metabolically distinct clusters due to minor changes in composition and increase in diversity. Clustering of 16S-based relative abundance data and the model data revealed that the rare Burkholderia infections are metabolically distinct from other CF communities, and are heavily dominated by this genus. It was also reiterated that Achromobacter infections are highly resilient to treatment. Linear regression analysis between lung function and microbiota diversity revealed no strong correlation across the population, however, diversity was found to first increase and then subsequently decrease drastically with disease severity.
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An Assessment of Potential False Positive E.coli Pyroprints in the CPLOP DatabaseGordon, Skyler A 01 February 2017 (has links)
The genetic information found in each species of organism is unique, and can be used as a tool to differentiate at the molecular level. This has caused rapid genotyping methods to become the cornerstone of a new area of research dependent on reading the genome as a form of identification. One of these specific identification methods, known as pyroprinting, relies on the small variation of DNA sequences within the same species to develop a unique, reproducible fingerprint. By simultaneously pyrosequencing multiple polymorphic loci within the ribosomal operons known as the intergenic transcribed spacers, a reproducible output is obtained, known as a pyroprint, which can be used like a fingerprint to identify that organism. This section of the genome not only differs between species but also between isolated bacteria within that species, allowing for the differentiation of species subtypes, referred to as strains. While this is a viable method for generating reproducible fingerprints from individual strains it may be possible to obtain identical fingerprints from non-identical organisms. The following report uses direct sequence comparison and in silico pyrosequencing of E. coli isolates housed in the Center for Applications in Biotechnology at California Polytechnic State University, San Luis Obispo that have matching pyroprints to show that it is possible to receive near identical pyroprints from non-identical sequences of intergenic transcribed spacers. Although the exact likelihood and cause of this false positive result remains undetermined due to limitations in the sequencing method, its existence questions the accuracy of using pyroprints of the ITS regions as a method of strain classification.
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