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Articles 3091 - 3120 of 8389

Full-Text Articles in Microbiology

Microbial Degradability Of Terrigenous, Marsh-Exported, And Estuarine Colored Dissolved Organic Matter In Long Island Sound, John R. Supino Jan 2020

Microbial Degradability Of Terrigenous, Marsh-Exported, And Estuarine Colored Dissolved Organic Matter In Long Island Sound, John R. Supino

Dissertations and Theses

The Long Island Sound is one of the world's most urbanized estuaries, polluted from excess nutrients which impact the quality of water through increased biological productivity. Dissolved organic matter (DOM) is a sensitive indicator of anthropogenic pollution and nutrient enrichment in coastal waters as well as an important part of the carbon cycle and serves as a primary food source for aquatic food webs. Additionally, the colored portion of DOM (CDOM) impacts coastal optical properties, ocean color, and light attenuation. High levels of CDOM have been shown to inhibit the growth of phytoplankton and limit photosynthesis, damaging the food chain …

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Pertussis Resurgence In Europe: Incidence And Epidemiologic Cycles In Immunization Required And Non-Required Countries, Sheryl Ann Duquet Jan 2020

Pertussis Resurgence In Europe: Incidence And Epidemiologic Cycles In Immunization Required And Non-Required Countries, Sheryl Ann Duquet

Walden Dissertations and Doctoral Studies

Although pertussis vaccines have been available for over 7 decades, countries are experiencing a pertussis resurgence. This study sought to establish a relationship between the European pertussis immunization schedule designs (with and without the inclusion of adolescent boosters) and the immunization requirement (recommended or required), which potentially influences immunity waning, and thus the incidence rate and epidemiologic cycles of pertussis. The theoretical foundation for this study was the theory of herd immunity. A quantitative research method was used, supported by a secondary data source. The statistical analysis included the use of linear regression to evaluate the relationship between the requirement …

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Characterization Of The Putative Polysaccharide Synthase Cpsa And Its Effects On The Virulence Of The Human Pathogen Aspergillus Fumigatus, Binita Nepal Jan 2020

Characterization Of The Putative Polysaccharide Synthase Cpsa And Its Effects On The Virulence Of The Human Pathogen Aspergillus Fumigatus, Binita Nepal

Graduate Research Theses & Dissertations

The fungus Aspergillus fumigatus is a ubiquitous opportunistic human pathogen capable of causing a life-threatening disease called invasive aspergillosis, or IA, with an associated 40–90% mortality rate in immunocompromised patients. Of the approximately 250 species known in the genus Aspergillus, A. fumigatus is responsible for up to 90% of IA infections. This study focuses on examining the role of the putative polysaccharide synthase cpsA gene in A. fumigatus virulence. Additionally, we evaluated its role in cellular processes that influence invasion and colonization of host tissue. Importantly, our results support that cpsA is indispensable for virulence in A. fumigatus infection of …

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Bioinformatic Anlayses Of Identified But Uncultivated Microbial Dark Matter Organisms Using Archival Single Amplified Genomes (Sags), Daniel Adam Nuccio Jan 2020

Bioinformatic Anlayses Of Identified But Uncultivated Microbial Dark Matter Organisms Using Archival Single Amplified Genomes (Sags), Daniel Adam Nuccio

Graduate Research Theses & Dissertations

This project characterizes two independent, previously undescribed microbial dark matter organisms from the candidate phyla JL-ETNP-Z39 and NBK19. These characterizations are based on seven single amplified genomes (SAGs) for JL-ETNP-Z39 and six SAGs for NBK19. All SAGs used were provided by the Bigelow Laboratory for Ocean Sciences Single-Cell Genomics Center (scgc.bigelow.org). Bioinformatic analyses using a combination of publicly available software and custom scripting written in the computer programming languages Python and R were carried out to determine the basic genomic properties, evolutionary relatedness, representative environmental pangenomes, and metabolic properties of these organisms. Analyses indicated that the examined JL-ETNP-Z39 SAGs are …

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Acetaldehyde Production By Rothia Mucilaginosa Isolates From Patients With Oral Leukoplakia., Abdrazak Amer, Aine Whelan, Nezar N. Al-Hebshi, Claire M. Healy, Gary P. Moran Jan 2020

Acetaldehyde Production By Rothia Mucilaginosa Isolates From Patients With Oral Leukoplakia., Abdrazak Amer, Aine Whelan, Nezar N. Al-Hebshi, Claire M. Healy, Gary P. Moran

Articles

Rothia mucilaginosa has been found at high abundance on oral leukoplakia (OLK). The ability of clinical isolates to produce acetaldehyde (ACH) from ethanol has not been investigated. The objective of the current study was to determine the capacity of R. mucilaginosa isolates recovered from OLK to generate ACH. Analysis of R. mucilaginosa genomes (n = 70) shows that this species does not normally encode acetaldehyde dehydrogenase (ALDH) required for detoxification of ACH. The predicted OLK metagenome also exhibited reduced ALDH coding capacity. We analysed ACH production in 8 isolates of R. mucilaginosa and showed that this species is capable of …

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The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd Jan 2020

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …

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Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust Jan 2020

Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ergot alkaloids are fungal tryptophan derived toxins which affect mammalian circulation and neurotransmission. These compounds are biosynthesized by a conserved genetic pathway, known as the ergot alkaloid synthesis (EAS) pathway by fungi belonging to the ascomycete families Trichocomaceae and Clavicipitaceae. Several Ipomoea species and related plants in the morning glory family harbor vertically transmitted symbiotic fungi in the genus Periglandula, also members of Clavicipitaceae, that produce ergot alkaloids. Metabolomic analysis of seeds identified a previously uncharacterized glycoside form of the pharmaceutically important ergot alkaloid, ergonovine. Several species belonging to the fungal genus Metarhizium have recently been shown to have the …

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Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels Jan 2020

Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels

Graduate Theses, Dissertations, and Problem Reports (ETD)

The demand for natural gas, and the need for efficient extraction, has led to the development of unconventional oil and natural gas (UOG) techniques. Due to the novelty of UOG, the potential impacts to freshwater ecosystems are not fully understood. We used a dual pronged approach to study the effects of UOG development on microbial biodiversity and function via a laboratory microcosm experiment and a survey study of streams with and without UOG development within their watersheds. The laboratory microcosm study simulated stream contamination with produced water, a byproduct of UOG operation, using sediment collected from one high water-quality stream …

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The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio Jan 2020

The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio

Graduate Theses, Dissertations, and Problem Reports (ETD)

The acquisition of microbial partners is a strategy used by a diverse group of arthropods to overcome ecological barriers that might normally make certain niches uninhabitable. The unique phylogenetic opportunities attainable from the natural experiment of the Sodalis-allied clade allow for better understanding of how molecular structures evolve through time. Here, we focus on the evolution of the flagellar synthesis pathway, due to its complexity and ability to diverge in response to ecological pressures. We used this molecular pathway and natural experiment to show that normal evolutionary outcomes associated with symbiosis (i.e., genome reduction) do not explain the predicted conservation …

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Genomic And Taxonomic Studies Of An Antarctic Psychrotolerant Quorum Quenching Bacterium, Planococcus Versutus L10.15t, See-Too Wah Seng Jan 2020

Genomic And Taxonomic Studies Of An Antarctic Psychrotolerant Quorum Quenching Bacterium, Planococcus Versutus L10.15t, See-Too Wah Seng

Student Works (2020-2029)

Quorum quenching (QQ) has been suggested as an alternative to antibiotic treatments for pathogenic infections as it does not affect the viability of the pathogen and imposes minimum selection pressure promoting drug resistance. During an ecological survey for quorum quenching (QQ) bacteria from soil collected in Lagoon Island (Ryder Bay, Adelaide Island, Antarctica), a bacterial strain was isolated and identified as Planococcus species, L10.15T, based on 16S rRNA gene analysis. The genomic, phylogenetic, chemotaxonomic and phenotypic data obtained showed that L10.15T represents a novel species for which the name Planococcus versutus sp. nov. is proposed. Previously, QQ activity of L10.15T …

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Wading In A Glycan Sea: Investigations Of, And Developing Bioinformatic Tools For, Carbohydrate Active Enzymes And Gene Clusters In Prokaryotes, Catherine Ann Ausland Jan 2020

Wading In A Glycan Sea: Investigations Of, And Developing Bioinformatic Tools For, Carbohydrate Active Enzymes And Gene Clusters In Prokaryotes, Catherine Ann Ausland

Graduate Research Theses & Dissertations

Carbohydrates are immensely important biomolecule found in all organisms on earth, serving roles in structure, energy storage, protection and/or cell signaling. Carbohydrates are composed of an immense diversity of linkages, monosaccharide moieties and substitutions making them likely the most diverse biomolecule on earth, as well as the most abundant, being synthesized by plants and algae. Carbohydrates are synthesized and degraded by all organisms on earth through the expression of carbohydrate active enzymes, or ‘CAZymes’. In bacteria, CAZymes have been characterized to cluster in with transporters, regulators and/or other genes in so-called ‘polysaccharide utilization loci’, or PULs, to degrade carbohydrate substrates …

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Neurodegenerative Modeling: Tau Protein, Degradative Pathways, And Gene Expression Profiling Of Human Ipsc-Derived Neural Precursors And Differentiated 3-D Neural Sphere Versus 2-D Monolayer Cultures, Kyle H. Anthoney Jan 2020

Neurodegenerative Modeling: Tau Protein, Degradative Pathways, And Gene Expression Profiling Of Human Ipsc-Derived Neural Precursors And Differentiated 3-D Neural Sphere Versus 2-D Monolayer Cultures, Kyle H. Anthoney

Cal Poly Humboldt theses and projects

Human induced pluripotent stem cells offer a model for human brain development and disease by differentiation into brain organoids; however, current neural culture systems lack the microenvironment, neuronal circuits and connectivity, vascular circulation, and immune system that exist in vivo. After differentiation and development of neuronal and non-neuronal cell types within two formats of cell cultures, we can visualize and recapitulate in vivo protein accumulation, gene expression, and degradative processes such as autophagy. Using RNA extraction, purification methods and reverse transcription I compared traditional monolayer cultures and novel 3-D neural sphere cultures via gene expression analysis. This analysis indicated …

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Microcystins And Liver Disease Mortality, Insights From An Ecological Study, Rajesh Tirpaul Melaram Jan 2020

Microcystins And Liver Disease Mortality, Insights From An Ecological Study, Rajesh Tirpaul Melaram

Walden Dissertations and Doctoral Studies

Microcystins (MCs) are toxic secondary metabolites produced by freshwater cyanobacteria. Algal bloom subsidence can stimulate MC release, which can impair liver function if orally exposed to in large doses. The purpose of this retrospective, U.S. ecological study was to determine if MC exposure represented an environmental risk factor for liver disease mortality using a socioecological approach. A longitudinal ecological substudy investigated the association between average total MCs in Lake Washington and Lake Manatee and age-adjusted chronic liver disease (CLD)/cirrhosis death rates in Brevard County and Manatee County, Florida (FL). A prediction model of total MCs was deduced by quantifying levels …

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Novel Hiv Adaptation Strategy Against Host Cd8 T Cell Immunity, Kai Qin Jan 2020

Novel Hiv Adaptation Strategy Against Host Cd8 T Cell Immunity, Kai Qin

All ETDs from UAB

Since the 1980s, HIV infection has caused millions of death and tremendous economic losses worldwide. Despite great scientific advances, the only effective therapy to date, antiretroviral therapy (ART), merely delays disease progression yet cannot eradicate viral infection. Therefore, an effective HIV vaccine that can prevent the acquisition of infection would be a desirable alternative. The critical role of CD8 T-cell immunity in HIV infection has been well documented and therefore not surprisingly a great deal of effort has been focused on developing an effective CD8 T-cell based HIV vaccine. However, by far, such CD8 T-cell based HIV vaccine trials have …

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Elucidating The Targets And Function Of The Mlr Compass-Like Complex During Development, David Joseph Ford Jan 2020

Elucidating The Targets And Function Of The Mlr Compass-Like Complex During Development, David Joseph Ford

Dissertations

MLR COMPASS-like complexes are highly-conserved epigenetic regulators required for enhancer establishment and subsequent reprogramming during differentiation and development. Mutation of MLR complex subunits in humans is associated with cancer and developmental disorder, yet much remains to be determined concerning both the healthy and disease-altered functions of these complexes. Using the developmental model Drosophila melanogaster, I further elucidate the functions of the MLR complex during in vivo organ development as well as stress response. I characterize the miRNa bantam as a regulatory target of the complex, required for proper tissue patterning during wing and compound eye formation. in the same systems …

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Elucidating The Impact And Mechanism Of Hepatitis C Virus Cell-To-Cell Spread, Karina Durso-Cain Jan 2020

Elucidating The Impact And Mechanism Of Hepatitis C Virus Cell-To-Cell Spread, Karina Durso-Cain

Dissertations

Virus cell-to-cell spread has been implicated in the establishment of persistent infection and has been shown to be involved in the transmission of antiviral resistant mutants. However, relatively little is known about how virus cell-to-cell spread impacts infection or the specific mechanisms by which cell-to-cell spread occurs. as such, this dissertation focused on investigating HCV cell-to-cell spread not only to learn more about this medically important virus, but also to determine the broader impact cell-to-cell spread has on viral infection dynamics, identify the cellular factors involved, and perhaps ultimately provide insight into antiviral strategies that might enhance the barrier to …

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Distinct Roles For Carbohydrate And Protein Receptors In Coronavirus Infection, Enya Qing Jan 2020

Distinct Roles For Carbohydrate And Protein Receptors In Coronavirus Infection, Enya Qing

Dissertations

Coronaviruses (CoVs) are common human and animal pathogens. in humans, four endemic CoV species together account for one third of mild respiratory infections worldwide. More severe and frequently fatal respiratory pathologies are caused by recent CoV outbreaks that resulted from occasional zoonotic spillover from animal CoV reservoirs, namely, SARS-CoV in 2002, MERS-CoV in 2012, and SARS-CoV-2 in 2019. Because CoVs threaten global health, any chance of relieving CoV's threat on human populations would rely heavily on our understanding of the mechanistic requirements for CoV tropism, whose major determinant is at the level of viral entry. CoVs have evolved to use …

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Zika Virus Inactivates Polyamine Catabolism Via Alternative Splicing To Enhance Infection, Marion Lea Graham Jan 2020

Zika Virus Inactivates Polyamine Catabolism Via Alternative Splicing To Enhance Infection, Marion Lea Graham

Master's Theses

During viral infection, the virus and host must compete for resources inside the cell. One of these resources is polyamines. Polyamines are small, positively charged molecules that are found in all eukaryotic cells. They play a key role in several cellular functions including growth and proliferation, transcription and translation, and membrane stability. Viruses also rely polyamines for productive replication, utilizing them during DNA/RNa polymerization, nucleic acid packaging, and protein synthesis. in response to a virus infecting a host cell, the host cell will begin to regulate polyamine levels as a way to combat the infection. Polyamine levels are regulated by …

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Investigating The Role Of Hypusine In Viral Translation And Infection, Jeremy Joseph Esin Jan 2020

Investigating The Role Of Hypusine In Viral Translation And Infection, Jeremy Joseph Esin

Master's Theses

Polyamines are small, positively charged, molecules found in eukaryotic cells with roles in cellular function and viral infection. in previous work we have shown RNa viruses, including bunyaviruses, to be sensitive to polyamine depletion, but exact mechanisms are unknown. Bunyaviruses are emerging pathogens that cause encephalitis, hemorrhagic fevers, and meningitis. Rift Valley Fever Virus is a bunyavirus that infects both humans and livestock with severe mortality and morbidity. in previous work done with Rift Valley Fever Virus polyamine depleted results in noninfectious interfering particles without affecting the shape or size of the particles. Here, I investigate a specific metabolic pathway …

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A Susceptibility Study Of Urinary Isolates To Methenamine Hippurate And Its Metabolites, Nancy Sloan Jan 2020

A Susceptibility Study Of Urinary Isolates To Methenamine Hippurate And Its Metabolites, Nancy Sloan

Master's Theses

Urinary Tract Infection (UTI) is one of the most common bacterial infections in adult women. Treatment is one of the most common reasons for antibiotic prescription. the rise of antibiotic-resistant infections coupled with the shortage of new antibiotics creates an urgent need for alternative non-antibiotic treatments. One alternative is methenamine hippurate (MH), which is a non-antibiotic prophylaxis. It is reported to be active against some common uropathogens including Escherichia coli and Enterococcus species, but its effects on the newly discovered bladder microbiota (urobiome) are undocumented. Given this knowledge gap, this study aimed to evaluate the drug's spectrum of susceptibility on …

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Determining Interactions Between Bacteriophage And Urinary Microbiome Lysogens, Michael Bochert Jan 2020

Determining Interactions Between Bacteriophage And Urinary Microbiome Lysogens, Michael Bochert

Master's Theses

Bacteriophages (phages) are viruses that infect bacteria. They are the most abundant life forms on earth. It is estimated that there are approximately 10³⁰ phages on the planet (Chibani-Chennoufi et al. 2004). They outnumber their bacterial hosts approximately 10 to 1. Bacteria inhabit most niches on the planet including the human body, where they play critical roles in health and disease. Since phages shape bacterial populations the same way that viruses, such as smallpox and measles, shaped human populations, it is important to understand how they interact with their bacterial hosts. The majority of the phages that we know of …

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Molecular And Functional Analyses Of Serine Protease Genes In Halophilic Cyanobacterium Halothece Sp. Pcc 7418, Tanutcha Patipong Jan 2020

Molecular And Functional Analyses Of Serine Protease Genes In Halophilic Cyanobacterium Halothece Sp. Pcc 7418, Tanutcha Patipong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Serine proteases are a class of important proteolytic enzymes that contain a common serine residue, which functions as a nucleophile in the catalytic triad at the active site. They are ubiquitous and abundant proteins found in all living organisms with a wide array of molecular, cellular and physiological functions. In cyanobacteria, the information on serine protease functions is very limited, especially in halotolerant species. This study focuses on comparative analyses of serine proteases in a halotolerant cyanobacterium Halothece sp. PCC 7418 (Halothece 7418) and the model freshwater cyanobacterium Synechococcus elongatus PCC 7942, regulation under salt-stress condition and functional characterization of …

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การคัดกรองยีสต์โอลีจินัสและการผลิตน้ำมันจากทะลายปาล์มน้ำมันเปล่าเพื่อการผลิตไบโอดีเซล, ตฤณเศรษฐ์ วีระพันธุ์ Jan 2020

การคัดกรองยีสต์โอลีจินัสและการผลิตน้ำมันจากทะลายปาล์มน้ำมันเปล่าเพื่อการผลิตไบโอดีเซล, ตฤณเศรษฐ์ วีระพันธุ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

คัดกรองยีสต์โอลีจินัส Naganishia cerealis สายพันธุ์ IN1S2.5 ซึ่งมีน้ำมันสะสมในเซลล์ 24.79% (กรัม/กรัมเซลล์แห้ง) เมื่อเพาะเลี้ยงในอาหารเลี้ยงเชื้อสังเคราะห์ที่มีอัตราส่วนคาร์บอนต่อไนโตรเจนสูง ได้จากยีสต์ 39 ไอโซเลตซึ่งคัดแยกจากตัวอย่างที่เก็บจากอุทยานแห่งชาติดอยอินทนนท์ จังหวัดเชียงใหม่ ผลการประเมินศักยภาพของทะลายปาล์มน้ำมันเปล่าในการเป็นวัตถุดิบสำหรับผลิตน้ำมันยีสต์ N. cerealis IN1S2.5 และการนำน้ำมันยีสต์ที่ผลิตได้ไปใช้ประโยชน์ พบว่าทะลายปาล์มน้ำมันเปล่าให้น้ำตาลกลูโคสสูงสุด 16.67 กรัม/ลิตร เมื่อถูกปรับสภาพโดยการแช่ในโซเดียมไฮดรอกไซด์เข้มข้น 2 โมลาร์ (16 ชั่วโมง) จากนั้นระเบิดด้วยไอน้ำขณะแขวนลอยในโซเดียมไฮดรอกไซด์เข้มข้น 2.4% (น้ำหนัก/ปริมาตร) ที่ 200°ซ ความดัน 200 psi เป็นเวลา 5 นาที แล้วย่อยด้วยเซลลูเลส (6 ชั่วโมง) N. cerealis IN1S2.5 ที่เพาะเลี้ยงในไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่า ซึ่งเติมกลูโคส 75 กรัม/ลิตร โพแทสเซียมไดไฮโดรเจนฟอสเฟต 4 กรัม/ลิตร แคลเซียมคลอไรด์ไดไฮเดรต 0.05 กรัม/ลิตร และซิงค์ซัลเฟตเฮพตะไฮเดรต 0.02 กรัม/ลิตร พีเอช 4.0 ให้ผลผลิตน้ำมันสูงสุด 2.46 กรัม/ลิตร จากการทำนายคุณสมบัติของไบโอดีเซลที่ผลิตได้ แสดงให้เห็นว่าน้ำมันยีสต์ N. cerealis IN1S2.5 มีศักยภาพที่จะเป็นวัตถุดิบสำหรับผลิตไบโอดีเซล นอกจากนี้ได้ประเมินศักยภาพของไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่าในการเป็นวัตถุดิบสำหรับผลิตกรดปาล์มิโตเลอิกโดยใช้ยีสต์โอลีจินัส Cyberlindnera subsufficiens สายพันธุ์ NG8.2 การเพาะเลี้ยง Cy. subsufficiens NG8.2 ในไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่าที่ผสมกับไฮโดรไลเสตแป้งมันสำปะหลัง เพื่อทำให้ความเข้มข้นของน้ำตาลในไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่าสูงขึ้น ทำให้ได้น้ำมันที่มีกรดปาล์มิโตเลอิกสูงกว่า การเพาะเลี้ยงในไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่าซึ่งทำให้ความเข้มข้นของน้ำตาลสูงขึ้นโดยการนำเอาสารละลายกลูโคสมาผสม การเติมโพแทสเซียมไดไฮโดรเจนฟอสเฟต 1 กรัม/ลิตร แมกนีเซียมซัลเฟตเฮพตะไฮเดรต 0.5 กรัม/ลิตร และแคลเซียมคลอไรด์ไดไฮเดรต 0.1 กรัม/ลิตร ลงในสารละลายผสมระหว่างไฮโดรไลเสตทะลายปาล์มน้ำมันเปล่ากับไฮโดรไลเสตแป้งมันสำปะหลัง ที่พีเอช 5.0 ทำให้ผลผลิตน้ำมันเพิ่มขึ้นเป็น 1.96 กรัม/ลิตร การลดอุณหภูมิการบ่มจาก 30°ซ เป็น 25°ซ ทำให้กรดปาล์มิโตเลอิกในน้ำมันเพิ่มขึ้นจาก …

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การคัดกรองยีสต์ผลิตน้ำมันและการหาภาวะเหมาะที่สุดของการผลิตน้ำมันจากไฮโดรไลเสตของใบอ้อย, พัชราภรณ์ หุ่นดี Jan 2020

การคัดกรองยีสต์ผลิตน้ำมันและการหาภาวะเหมาะที่สุดของการผลิตน้ำมันจากไฮโดรไลเสตของใบอ้อย, พัชราภรณ์ หุ่นดี

Chulalongkorn University Theses and Dissertations (Chula ETD)

ยีสต์ 223 ไอโซเลต ที่คัดแยกได้จาก 223 ตัวอย่าง ที่เก็บจากแหล่งธรรมชาติ 9 แห่งในประเทศไทย ถูกนำมาคัดกรองยีสต์ที่สะสมน้ำมันในเซลล์สูง การคัดกรองเบื้องต้นโดยการย้อมเซลล์ด้วยสีไนล์เรด พบว่ามียีสต์ 16 สายพันธุ์ที่มีขนาดหยดน้ำมันภายในเซลล์ใหญ่กว่าครึ่งหนึ่งของขนาดเซลล์ ผลการวิเคราะห์ปริมาณน้ำมันสะสมภายในเซลล์ยีสต์เหล่านี้โดยเลี้ยงในอาหารผลิตน้ำมันที่ทราบองค์ประกอบทางเคมี ซึ่งมีกลูโคส 50 กรัม/ลิตร เป็นแหล่งคาร์บอน และบ่มที่อุณหภูมิ 30 องศาเซลเซียส เขย่า 200 รอบต่อนาที เป็นเวลา 6 วัน พบว่า Papiliotrema laurentii N-16.2, Rhodotorula (Rh.) sphaerocarpa 11-14.4, Saitozyma (Sait.) podzolica 11-11.3.1 และ Sait. podzolica N-8.4 เป็นยีสต์อุดมน้ำมัน การศึกษาการผลิตน้ำมันจากไฮโดรไลเสตใบอ้อย (sugarcane leaves hydrolysate, SLH) ของยีสต์อุดมน้ำมันที่คัดกรองได้ พบว่าทุกสายพันธุ์สามารถผลิตน้ำมันในไฮโดรไลเสตใบอ้อย โดย Rh. sphaerocarpa 11-14.4 ให้ผลผลิตน้ำมันสูงที่สุด (0.98 กรัม/ลิตร) การหาภาวะเหมาะที่สุดต่อการผลิตน้ำมันของ Rh. sphaerocarpa 11-14.4 ในไฮโดรไลเสตใบอ้อย พบว่าเมื่อใช้กล้าเชื้อที่เลี้ยงใน SLH ที่ผ่านการปรับด่างเกิน (overliming) (6% -DSLH) ที่เติมสารสกัดจากเซลล์ยีสต์ 3 กรัม/ลิตร และเพปโทน 3 กรัม/ลิตร และผลิตน้ำมันใน 12%-SLH (อัตราส่วนคาร์บอน/ไนโตรเจน เท่ากับ 24) ที่เติมโพแทสเซียมไดไฮโดรเจนฟอสเฟต (KH2PO4) 5 กรัม/ลิตร พีเอช 4.5 บ่มที่อุณหภูมิ 30 องศาเซลเซียส เขย่า 200 รอบต่อนาที เป็นเวลา 4 วัน ที่ภาวะดังกล่าวนี้ Rh. sphaerocarpa 11-14.4 …

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Dna Analysis And The Postmortem Submersion Interval From The Microbiome Of Waterlogged Sus Scrofa Skeletal Remains, Claire Cartozzo Jan 2020

Dna Analysis And The Postmortem Submersion Interval From The Microbiome Of Waterlogged Sus Scrofa Skeletal Remains, Claire Cartozzo

Theses and Dissertations

Following water-related deaths, soft tissue on victims’ remains may be entirely absent after a temperature dependent period of time. Due to their physical and chemical components, which protect them from environmental deterioration and biological attack, bones preserve DNA for longer periods of time. Therefore, the ability to both identify an individual and estimate the postmortem submersion interval (PMSI) may depend on DNA obtained from skeletal remains. The goals of the dissertation were to examine differences in both the degradation of skeletal DNA and the microbiome inhabiting bone in freshwater aquatic environments (e.g., Henley Lake and the James River). At each …

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The Pseudomonas Aeruginosa Interactome: Insights Into Srna-Mediated Regulatory Networks, Christine M. Van Duyn Jan 2020

The Pseudomonas Aeruginosa Interactome: Insights Into Srna-Mediated Regulatory Networks, Christine M. Van Duyn

Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacterium found in various environmental niches including soil, water, hospital environments, and within a broad range of hosts. It is well known for its metabolic versatility and intrinsic and acquired resistance to a variety of antimicrobial agents. Moreover, this bacterium has a remarkable ability to adapt and survive in suboptimal environments by altering its transcriptional profile in response to nutrient deprivation, changes in temperature and pH, osmotic stress, the presence of reactive oxygen species (ROS), and exposure to antibiotics and host defenses. P. aeruginosa colonizes individuals with compromised immune systems and severe burn injuries and …

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Development Of A Screening Assay For Type Iii Secretion System Inhibitors And High Throughput Screening Campaign Of Inhibitors Of Prp Of Staphylococcus Aureus, Heather A. Pendergrass Jan 2020

Development Of A Screening Assay For Type Iii Secretion System Inhibitors And High Throughput Screening Campaign Of Inhibitors Of Prp Of Staphylococcus Aureus, Heather A. Pendergrass

Theses and Dissertations

Antibiotics inhibit the growth or survival of bacteria by targeting their essential functions.1 Due to weaknesses in traditional antibiotics and the increasing prevalence of antibiotic resistance genes, virulence factors are being targeted for therapeutic treatment of bacterial infection.2 We have developed an assay to quantify and observe type III secretion system (T3SS) activity. The type III secretion system (T3SS) is a virulence factor present in some Gram-negative pathogens including enteropathogenic and enterohemorrhagic E. coli (EPEC and EHEC, respectively),3 and others.4–9 The T3SS between EPEC and EHEC are highly conserved and share over 90% sequence identity with …

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In Vivo Activity Of Copper(Ii), Manganese(Ii), And Silver(I) 1,10-Phenanthroline Chelates, Rafael M. Ghandra, Pauraic Mccarron, Livia Viganor, Mariana Farias Fernandes, Kevin Kavanagh, Malachy Mccann, Marta H. Branquinha, André L.S. Santos, Orla L. Howe, Michael Devereux Jan 2020

In Vivo Activity Of Copper(Ii), Manganese(Ii), And Silver(I) 1,10-Phenanthroline Chelates, Rafael M. Ghandra, Pauraic Mccarron, Livia Viganor, Mariana Farias Fernandes, Kevin Kavanagh, Malachy Mccann, Marta H. Branquinha, André L.S. Santos, Orla L. Howe, Michael Devereux

Articles

Candida haemulonii is an emerging opportunistic pathogen resistant to most antifungal drugs currently used in clinical arena. Metal complexes containing 1,10-phenanthroline (phen) chelating ligands have well-established anti-Candida activity against different medically relevant species. This study utilized larvae of Galleria mellonella, a widely used model of in vivo infection, to examine C. haemulonii infection characteristics in response to different copper(II), manganese(II), and silver(I) chelates containing phen, which had demonstrated potent anti-C. haemulonii activity in a previous study. The results showed that C. haemulonii virulence was influenced by inoculum size and incubation temperature, and the host G. mellonella immune …

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Helicobacter Pylori Gene Regulation By Virulence Region Located Srnas, Veronica Janette Albrecht Jan 2020

Helicobacter Pylori Gene Regulation By Virulence Region Located Srnas, Veronica Janette Albrecht

EWU Masters Thesis Collection

Approximately 50% of the human population is infected with Helicobacter pylori, which can lead to gastrointestinal diseases such as ulcers and gastric adenocarcinoma. Helicobacter pylori strains are genetically variable, and some contain a DNA region called the cytotoxin associated gene pathogenicity island (cagPAI) that encodes virulence factors. Gastrointestinal disease associated with H. pylori are more likely to occur in infections with cagPAI positive strains. Helicobacter pylori has few known transcriptional regulators, but still must regulate expression to survive a constantly changing environment. A mechanism to facilitate this regulation was revealed in a transcriptome analysis conducted by Sharma et al. (2010) …

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Impact Of Chytrid Fungus Pathogen On The Skin Microbiome Of Frogs In Northern Idaho And Turnbull National Wildlife Refuge, Washington, Philip M. Campos Jan 2020

Impact Of Chytrid Fungus Pathogen On The Skin Microbiome Of Frogs In Northern Idaho And Turnbull National Wildlife Refuge, Washington, Philip M. Campos

EWU Masters Thesis Collection

Amphibians worldwide are under threat from the infectious disease chytridiomycosis, which is caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd). Bd is associated with the population declines of an estimated 501 species, 90 of which are presumed or confirmed extinct, making this the greatest documented loss of biodiversity attributed to a disease. Researching the amphibian skin microbiome may provide solutions to conservation of amphibians. Two main relationships have been observed between Bd and the microbiome: 1) bacteria producing antifungal metabolites can inhibit Bd and improve survival against the disease and 2) infection by Bd is believed to affect the composition …

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