Selenium Vs. Sulfur: Investigating The Substrate Specificity Of A Selenocysteine Lyase,
2019
University of Central Florida
Selenium Vs. Sulfur: Investigating The Substrate Specificity Of A Selenocysteine Lyase, Michael Johnstone
Electronic Theses and Dissertations
Selenium is a vital micronutrient in many organisms. While traces are required for survival, excess amounts are toxic; thus, selenium can be regarded as a biological "double-edged sword". Selenium is chemically similar to the essential element sulfur, but curiously, evolution has selected the former over the latter for a subset of oxidoreductases. Enzymes involved in sulfur metabolism are less discriminate in terms of preventing selenium incorporation; however, its specific incorporation into selenoproteins reveals a highly discriminate process that is not completely understood. In this work, we add knowledge to the mechanism for selenium-over-sulfur specificity in hopes of further understanding the …
Prevention Of Harmful Algal Blooms By The Mitigation Of Phosphorus Nutrient Loading Via Filtration By Steel Wool And Activated Carbon,
2019
The University of Akron
Prevention Of Harmful Algal Blooms By The Mitigation Of Phosphorus Nutrient Loading Via Filtration By Steel Wool And Activated Carbon, Ronald Simpson, Sara Kidd, Samantha Zidd
Williams Honors College, Honors Research Projects
Harmful Algal Blooms (HABs) are a devastating ecological and economic consequence of the abundance of nutrient-rich agricultural runoff entering aquatic ecosystems (Baker et al. 2014). Bio-available phosphorus from synthetic fertilizers is one of the major nutrients contributing to this global issue. Previous studies indicated that dissolved phosphorus can be removed from an aqueous environment when passed through a composite mixture of granular steel wool particles and activated carbon (Erickson, Gulliver, and Weiss, 2007). In this project, we conducted experiments using higher quality concentration measurements to determine what grades of steel wool (SW-0000, SW-000, SW-00) and types of activated carbon (granulated …
Student Understanding Of Dna Structure–Function Relationships Improves From Using 3d Learning Modules With Dynamic 3d Printed Models,
2019
University of Nebraska-Lincoln
Student Understanding Of Dna Structure–Function Relationships Improves From Using 3d Learning Modules With Dynamic 3d Printed Models, Michelle E. Howell, Christine S. Booth, Sharmin M. Sikich, Tomáš Helikar, Rebecca Roston, Brain A. Couch, Karin Van Dijk
Department of Biochemistry: Faculty Publications
Understanding the relationship between molecular structure and function represents an important goal of undergraduate life sciences. Although evidence suggests that handling physical models supports gains in student understanding of structure–function relationships, such models have not been widely implemented in biochemistry classrooms. Three-dimensional (3D) printing represents an emerging cost-effective means of producing molecular models to help students investigate structure–function concepts. We developed three interactive learning modules with dynamic 3D printed models to help biochemistry students visualize biomolecular structures and address particular misconceptions. These modules targeted specific learning objectives related to DNA and RNA structure, transcription factor-DNA interactions, and DNA supercoiling dynamics. …
Acyltransferases And Methods Of
Using,
2019
Lincoln, NE
Acyltransferases And Methods Of Using, Edgar Cahoon, Umidjon Iskandarov, Hae Jin Kim, Jillian Collins-Silva
Department of Biochemistry: Faculty Publications
Provided herein are novel acyltransferases and methods of using such novel acyltransferases in making medium - chain fatty acids.
The Structure Of Pila From Acinetobacter Baumannii Ab5075 Suggests A Mechanism For Functional Specialization In
Acinetobacter Type Iv Pili,
2019
University of Nebraska-Lincoln
The Structure Of Pila From Acinetobacter Baumannii Ab5075 Suggests A Mechanism For Functional Specialization In Acinetobacter Type Iv Pili, Leslie A. Ronish, Erik Lillehoj, James K. Fields, Eric J. Sundberg, Kurt Piepenbrink
Department of Biochemistry: Faculty Publications
Type IV pili (T4P) are bacterial appendages composed of protein subunits, called pilins, noncovalently assembled into helical fibers. T4P are essential, in many bacterial species, for processes as diverse as twitching motility, natural competence, biofilm or microcolony formation, and host cell adhesion. The genes encoding type IV pili are found universally in the Gram-negative, aerobic, nonflagellated, and pathogenic coccobacillus Acinetobacter baumannii, but there is considerable variation in PilA, the major protein subunit, both in amino acid sequence and in glycosylation patterns. Here we report the X-ray crystal structure of PilA from AB5075, a recently characterized, highly virulent isolate, at …
Preconditioning Of The Tumor Microenvironment By Means Of Low Dose Chemotherapies For An Effective Immunotherapy Of Breast Cancer,
2019
Virginia Commonwealth University
Preconditioning Of The Tumor Microenvironment By Means Of Low Dose Chemotherapies For An Effective Immunotherapy Of Breast Cancer, Hussein F. Aqbi
Theses and Dissertations
Breast cancer mortality is mainly due to distant recurrence of the disease arising from dormant tumor cells established by cancer therapies. Patients who initially respond to cancer therapies often succumb to distant recurrence of the disease. It is not clear why people with the same type of breast cancer respond to treatments differently; some escape from dormancy and relapse earlier than others. In addition, some tumor clones respond to immunotherapy while others do not. We investigated how autophagy plays a role in accelerating or delaying recurrence of neu overexpressing mouse mammary carcinoma (MMC) following adriamycin (ADR) treatment, and in affecting …
First Record Of White Stork In A Birdstrike In South Africa Above 3,300 M Agl,
2019
National Zoological Garden South Africa National Biodiversity Institute
First Record Of White Stork In A Birdstrike In South Africa Above 3,300 M Agl, Desire Dalton, Marli De Bruyn, Monica Mwale, Kim Labuschagne, Melissa Hofmann, Albert Froneman, Hanneline A. Smit-Robinson, Antoinette Kotze
Human–Wildlife Interactions
Birdstrikes to aircrafts are increasing on an annual basis and pose significant aviation safety risks. Identification of the birds involved is key to developing mitigation strategies. Often the only information available to make identifications are feather and/or tissue samples. Relying on feathers alone to identify the bird species requires special expertise and access to museum collections for specimen comparisons. In 2017, feathers and tissue samples were recovered from the engine cowling of an airplane that had just landed at the Oliver Reginald (O. R.) Tambo international airport in South Africa after striking a bird at 3,353 m. To confirm the …
Field Evaluation Of Tobacco Engineered For High Leaf-Oil Accumulation,
2019
University of Kentucky
Field Evaluation Of Tobacco Engineered For High Leaf-Oil Accumulation, James Perry
Theses and Dissertations--Plant and Soil Sciences
The biofuel market is dominated by ethanol and biodiesel derived from cellulosic and lipid-based biomass crops. This is largely due to the relatively low costs and reliability of production. At present, production of non-food plant-derived oils for biofuel production in the U.S. is minimal. A research team from the Commonwealth Scientific and Industrial Research Organization (CSIRO), an independent Australian federal government research institution, has developed an efficient transgenic system to engineer oil production in tobacco leaves. This novel system is comprised of multiple transgenes that direct the endogenous metabolic flux of oil precursors towards triacylglycerol (TAG) production. Additional genes were …
Nanomaterials For Double-Stranded Rna Delivery,
2019
University of Kentucky
Nanomaterials For Double-Stranded Rna Delivery, Stuart Lichtenberg
Theses and Dissertations--Plant and Soil Sciences
RNA interference has enormous potential as a potent, specific, and environmentally friendly alternative to small molecule pesticides for crop protection. The use of exogenous double-stranded RNA offers flexibility in targeting and use in crops in which transgenic manipulation is not an option. The combination of RNAi with nanotechnology offers further advantages that are not available with dsRNA alone. In this work, I have evaluated several different combinations of nanomaterials and polymers for use in RNAi-based pest control systems. First, I have characterized the use of chitosan/dsRNA polyplex nanoparticles for gene knockdown using the model nematode Caenorhabditis elegans. Though chitosan/dsRNA …
Mechanisms Of Microglia Mediated Apolipoprotien E Neurotoxicity,
2019
CUNY City College
Mechanisms Of Microglia Mediated Apolipoprotien E Neurotoxicity, Pardeep Singh
Dissertations and Theses
No abstract provided.
Determining Differential Effects Of Interleukin-2 On Innate And Adaptive Immune Cells In Lymphoid Organs And The Gastrointestinal Tract,
2019
University of Central Florida
Determining Differential Effects Of Interleukin-2 On Innate And Adaptive Immune Cells In Lymphoid Organs And The Gastrointestinal Tract, Ayushi Singh
Electronic Theses and Dissertations
Interleukin-2 (IL-2) is a pleiotropic cytokine demonstrated to be effective in treating cancer. However, the clinical use of IL-2 can be associated with severe side effects including gastrointestinal toxicity (GT). Similar GT symptoms are observed in inflammatory diseases such as CD (CD). Interestingly mounting evidence indicates a role for IL-2 in CD, but the underlying mechanisms are unknown. Indeed, studies on the in-vivo activities of IL-2 have mostly focused on secondary lymphoid organs and immune cells associated with them. Very few studies have addressed how IL-2 signals impact populations of immune cells in the gut. Here, we aim to identify …
Atp Induced Molecular Disassembly Of Cytolethal Distending Toxin's B/C Heterodimer,
2019
University of Central Florida
Atp Induced Molecular Disassembly Of Cytolethal Distending Toxin's B/C Heterodimer, George Huhn
Electronic Theses and Dissertations
Cytolethal distending toxin (CDT) is a virulence factor produced by many Gram-negative bacteria, including Haemophilus ducreyi. This fastidious pathogen is the causative agent of genital cancroid. CDT is a heterotrimeric toxin with an AB2 structure consisting of a cell-binding "B" domain (CdtA + CdtC) and a catalytic "A" domain (CdtB) that has DNase activity. This toxin assembles in the bacterial periplasm that lacks ATP and is secreted into the extracellular environment. After cell binding, CDT is internalized by endocytosis and travels through the endosomes and Golgi before arriving in the endoplasmic reticulum (ER). CdtA is lost from the holotoxin before …
Biochemical Characterization Of Rv2633c From Mycobacterium Tuberculosis And The Effects Of Mutagenesis On Iron Binding,
2019
University of Central Florida
Biochemical Characterization Of Rv2633c From Mycobacterium Tuberculosis And The Effects Of Mutagenesis On Iron Binding, Kyle Strickland
Electronic Theses and Dissertations
Mycobacterium tuberculosis (Mtb) is a pathogenic bacterium that is the causative agent of the disease Tuberculosis (TB). TB kills an estimated 1.8 million people annually and roughly one third of the world's population carries Mtb in a dormant state. Drug resistant Mtb strains are on the rise, thus a new method of combating this disease is paramount. Mtb survival inside of macrophages requires overcoming various stressors such as; iron restriction, reactive oxygen species, and hypoxic conditions. Mtb employs the use of catalases, nitric oxide reductase, superoxide dismutase, and siderophores to aid in survival. These functions have also been found in …
Antioxidant And Antibacterial Agents From Parmotrema Dilatatum (Vainio) Hale, Knema Angustifolia (Roxb.) Warb. And Persicaria Odorata Lour,
2019
Faculty of Science
Antioxidant And Antibacterial Agents From Parmotrema Dilatatum (Vainio) Hale, Knema Angustifolia (Roxb.) Warb. And Persicaria Odorata Lour, Asshaima Paramita Devi
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the search of antioxidant and antibacterial agents, the extracts and isolated compounds from lichen Parmotrema dilatatum, Knema angustifolia full name, Persicaria odorata and Mansonia gagei. were examined. Nine compounds were isolated from lichen P. dilatatum including (E)-2,4-dihydroxy-6-methyl-3-(3-oxobut-1-en-1-yl)benzoate (PD.1), hopane-16ß,22-diol (PD.2), methyl orsellinate (PD.3), methyl haemmatomate (PD.4), methyl ß-orcinolcarboxylate (PD.5), 2-hydroxy-4-methoxy-3,6-dimethylbenzoic acid (PD.6), atranol (PD.7), atranorin (PD.8) and lecanorin (PD.9). The dichloromethane and acetone fractions, and atranol (PD.7) gave excellent activities as antioxidants. While in tyrosinase activity the dichloromethane fraction and atranorin (PD.8) showed the highest inhibition. For α-glucosidase inhibition activity, the methanol fraction and methyl haemmatommate (PD.4) revealed the …
Enhancement Of Biofuel Production In Microalgae By Genetic And Physiological Modification,
2019
Faculty of Science
Enhancement Of Biofuel Production In Microalgae By Genetic And Physiological Modification, Napisa Pattharaprachayakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Microalgae are photosynthetic microorganisms, which could be used as potential microbial cell factories by directly converting CO2 into valuable bioproducts and biofuels. This study aims to improve the target biofuel feedstocks from the isolated green alga Chlorella sp. and the engineered cyanobacterium Synechococcus elongatus PCC 7942 in terms of the improvement on lipids (as precursors of FAMEs) and terpene (α-farnesene), respectively. The first part is concerned with the enhancement of lipids and the determination of FAMEs and biodiesel properties in Chlorella sp. under the phosphorus (P) limitation (0-50%) alone or in combination with heavy metals (Fe, Co, Pb) supplementation. The …
Binding Kinetics Of Monoclonal Antibodies And Fluoroquinolone Derivatives,
2019
Faculty of Science
Binding Kinetics Of Monoclonal Antibodies And Fluoroquinolone Derivatives, Patamalai Boonserm
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fluoroquinolones (FQs) are a group of antibiotics which have been extensively used against both Gram-negative and Gram-positive bacteria. Some of FQs antibiotics commonly used in livestock and fishery include norfloxacin, enrofloxacin, ciprofloxacin, and ofloxacin. However, misuse of these antibiotics may cause drug residues in food products. Therefore, to prevent consumers from getting residual antibiotics in food and the drug resistance of pathogens in humans. As a result, surveillance detection program of these drug residues must be in practice to ensure safety of the consumers in many countries. In general, detections based on immunological method include enzyme-linked immunosorbent assay (ELISA) has …
Screening And Identification Of Probiotic Lactic Acid Bacteria From Plant Samplesd,
2019
Faculty of Science
Screening And Identification Of Probiotic Lactic Acid Bacteria From Plant Samplesd, Ratthanatda Nuhwa
Chulalongkorn University Theses and Dissertations (Chula ETD)
Seventy lactic acid bacteria (LAB) were isolated from flowers (17 strains), 3 tree barks (7 strains), one fruit (2 strains), ten fermented tea leaves (31 strains) and two silage (13 strains). They were identified as Lactobacillus pentosus (12 strains), L. plantarum subsp. plantarum (9 strains), L. paracasei subsp. tolerans (5 strains), L. brevis (1 strain), L. silagincola (1 strain), L. kunkeei (1 strain), and L. formosensis (1 strain), Enterococcus durans (3 strains), E. lactis (2 strains), E. faecalis (1 strain), E. faecium (1 strain), E. gallinarum (1 strain) and E. gilvus (1 strain), Pediococcus acidilactici (1 strain) and P. pentosaceus …
Development Of Oxidase Enzyme And Non-Enzyme Based Biosensors For Lactate And Creatinine Detection,
2019
Faculty of Science
Development Of Oxidase Enzyme And Non-Enzyme Based Biosensors For Lactate And Creatinine Detection, Siraprapa Boobphahom
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation focused on the development of electrochemical sensors based on metal oxides and graphene modified electrodes for clinical applications, which is divided into two parts. The first part is development of a biosensor based on lactate oxidase (LOx) immobilized on titanium dioxide sol (TiO2 sol)/graphene nanocomposite modified nickel (Ni) foam electrode for enzymatic electrochemical detection of lactate via hydrogen peroxide (H2O2) detection. A TiO2/graphene nanocomposite was simply synthesized by hydrolysis and coated on Ni foam electrode to develop a novel electrode in biosensor. The results showed that the well intercalation of TiO2 sol within graphene film covered on the …
Role Of Enzymes In Glyoxylate Cycle In Transgenic 'Kdml 105' Rice Oryza Sativa L. Overexpressing Oscam1-1 Under Salt Stress,
2019
Faculty of Science
Role Of Enzymes In Glyoxylate Cycle In Transgenic 'Kdml 105' Rice Oryza Sativa L. Overexpressing Oscam1-1 Under Salt Stress, Tanaporn Ausaha
Chulalongkorn University Theses and Dissertations (Chula ETD)
The previous study reported that the transcriptome profiling of the KDML 105 rice overexpressing OsCam1-1 widely affected the expression of genes involved in several cellular processes including the genes associated with the glyoxylate cycle, which exhibited up-regulation in KDML 105 overexpressing OsCam1-1 under salt stress. In this study, we focused on the role of the glyoxylate cycle in transgenic KDML 105 rice under salt stress. The phenotypes as follows: fresh weight and dry weight of shoot & root, SPAD value, activities of isocitrate lyase, and malate synthase; sugar, and starch contents, and total lipid content were investigated at 0, 2, …
การตรวจสอบเอนไซม์ลิงค์อิมมูโนซอร์เบนต์แอสเสย์สำหรับการตรวจวัดสารตกค้างกลุ่มแรคโตพามีนและการประยุกต์,
2019
คณะวิทยาศาสตร์
การตรวจสอบเอนไซม์ลิงค์อิมมูโนซอร์เบนต์แอสเสย์สำหรับการตรวจวัดสารตกค้างกลุ่มแรคโตพามีนและการประยุกต์, พลอยขวัญ พรหมพิทยายุทธ
Chulalongkorn University Theses and Dissertations (Chula ETD)
แรคโตพามีน (Ractopamine) เป็นสารในกลุ่มเบต้าอะโกนิสต์ (Beta-Agonist) ที่ถูกห้ามใช้ในประเทศไทย ดังนั้นงานวิจัยนี้จึงต้องการที่จะพัฒนาและทดสอบความใช้ได้ของวิธี Enzyme linked immunosorbent assay (ELISA) สำหรับตรวจวัดแรคโตพามีนตกค้างในเนื้อสัตว์ เครื่องในสัตว์และอาหารสัตว์ โดยได้เริ่มจากการพัฒนา ELISA 2 รูปแบบคือ indirect competitive ELISA และ direct competitive ELISA จากการทดสอบได้เลือก ELISA รูปแบบ direct competitive ELISA เนื่องจากมีค่าความไวที่สูงกว่าอีกรูปแบบ ค่า IC50 LOQ และ LOD เท่ากับ 0.57, 0.06 และ 0.02 นาโนกรัมต่อมิลลิลิตรตามลำดับ ทำการทดสอบความใช้ได้ของ direct competitive ELISA สำหรับนำไปตรวจวัดปริมาณแรคโตพามีนตกค้างในตัวอย่างกลุ่มเนื้อสัตว์ (เนื้อหมูและเนื้อโค) กลุ่มเครื่องในสัตว์ (ตับหมู ตับโคและไตหมู) และกลุ่มอาหารสัตว์ (อาหารหมูและอาหารโค) ทดสอบความไวของวิธี ELISA ในสารสกัดตัวอย่างต่างๆ พบว่า LOQ ของตัวอย่างอยู่ในช่วง 0.56-1.90 นาโนกรัมต่อกรัม และค่า LOD ของตัวอย่างอยู่ในช่วง 0.32-0.97 นาโนกรัมต่อกรัม ช่วงของการการตรวจวัดแรคโตพามีนในเนื้อหมูและไตหมูอยู่ที่ 0.4-6.25 นาโนกรัมต่อกรัม ในขณะที่ตัวอย่างอื่น ๆ มีช่วงของการตรวจวัดอยู่ที่ 0.8-12.5 นาโนกรัมต่อกรัม นอกจากนี้ได้ทดสอบการเกิดปฏิกิริยาข้ามพบว่าไม่เกิดปฏิกิริยาข้ามกับสารในกลุ่มเบต้าอะโกนิสต์ ความถูกต้อง (% recovery) และความแม่นยำ (%CV) มีค่าอยู่ในช่วง 64.06-109.80 % และ 6.26-28.87 % ตามลำดับ ค่าความสามารถในการตรวจวัด (CCβ) มีค่าอยู่ที่ 2 นาโนกรัมต่อกรัมสำหรับเนื้อหมูและไตหมู และ 3 นาโนกรัมต่อกรัมในตัวอย่างอื่นๆ โดยมีค่าความผิดพลาดผิดพลาดจากการตรวจวัดน้อยกว่าหรือเท่ากับ 5 % จากผลการทดสอบดังกล่าวพบว่าวิธี direct …
