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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Aptamer-Based Assay For Detection Of Ochratoxin A, Amanda Nicole Bartley Nov 2018

Aptamer-Based Assay For Detection Of Ochratoxin A, Amanda Nicole Bartley

FIU Electronic Theses and Dissertations

Ochratoxin A (OTA) is a potent mycotoxin found in a wide range of agricultural products that has been linked to mitochondrial damage and renal disease. The standard methods for OTA analysis currently rely on the use of high-performance liquid chromatography (HPLC) coupled to fluorescence detection or mass spectrometry. Toward a highthroughput analysis of OTA, a single-stranded DNA aptamer, modified with a fluorophore, coupled to a complementary sequence, modified with a FRET-based quencher that dissociates in the presence of the target toxin, is proposed. In order to integrate “target trapping,” aptamer immobilization methods were explored to mediate interference issues. Assays were ...


Investigating The Role Of The Proximal Cysteine Hydrogen Bonding Network And Distal Pocket In Chloroperoxidase, Elwood Kwong Lam Nov 2018

Investigating The Role Of The Proximal Cysteine Hydrogen Bonding Network And Distal Pocket In Chloroperoxidase, Elwood Kwong Lam

FIU Electronic Theses and Dissertations

Chloroperoxidase (CPO) is one of the most versatile heme enzyme isolated from the marine fungus, Caldariomyces fumago. Functionally, CPO can catalyze four types of reactions: peroxidation (peroxidase-like), dismutation (catalase-like), halogenation (halogenase-like), and peroxygenation (P450-like). Structurally, CPO has a distal and proximal pockets that can be best described as a hybrid of classical peroxidase and P450s. As a heme-thiolate protein, CPO contains the conserved proximal Pro28-Cys29-Pro30 stretch found in other members of the family. However, the structural and functional roles of these proline residues remain poorly understood. Site-directed mutagenesis was undertaken to generates three CPO mutants, P28A-, P30A-, P28A/P30A-CPO. The ...


Folding Analysis Of Reduced Bovine Pancreatic Trypsin Inhibitor (Bpti) With Aromatic Thiols And Disulfides In Vitro, Na Zhang Nov 2018

Folding Analysis Of Reduced Bovine Pancreatic Trypsin Inhibitor (Bpti) With Aromatic Thiols And Disulfides In Vitro, Na Zhang

FIU Electronic Theses and Dissertations

Almost all therapeutic proteins contain disulfide bonds to stabilize their native structure. Recombinant DNA technology enables many therapeutic proteins to be produced in bacteria, but the expression of native proteins is not always efficient due to the limited ability of bacteria to form disulfide bonds in vivo. It is often necessary to employ in vitro oxidative folding process to form the native disulfide bonds to obtain the native structure of disulfide-containing proteins. Aromatic disulfides are small molecules designed to match some of the physical properties of the active site of protein disulfide isomerase (PDI), which catalyzes the folding process of ...


Mycobacterium Tuberculosis Inhibitors: Action And Resistance, Pamela K. Garcia-Moreno Nov 2018

Mycobacterium Tuberculosis Inhibitors: Action And Resistance, Pamela K. Garcia-Moreno

FIU Electronic Theses and Dissertations

Tuberculosis, an infectious disease caused by Mycobacterium tuberculosis, has been a global health problem for years. The emergence of drug resistance in this organism generates the necessity of exploring novel targets and developing new drugs. Topoisomerases are enzymes found in all kingdoms of life responsible for overcoming the topological barriers encountered during essential cellular processes. The genomes of mycobacteria encode only one type IA topoisomerase (MtopI), which has been validated as a novel TB drug target. The goal of this study is to obtain new information on the mechanism and resistance of endogenous and synthetic inhibitors of MtopI.

Rv1495 is ...


Structure-Function Relationships In Hexacoordinate Heme Proteins: Mechanism Of Cytoglobin Interactions With Exogenous Ligands, Antonija Tangar Jun 2018

Structure-Function Relationships In Hexacoordinate Heme Proteins: Mechanism Of Cytoglobin Interactions With Exogenous Ligands, Antonija Tangar

FIU Electronic Theses and Dissertations

Cytoglobin (Cygb) and neuroglobin (Ngb) are among the newest members of vertebrate globin family characterized by a classical 3-over-3 α-helical fold and a heme prosthetic group capable of reversibly binding small ligands such as O2, CO and NO. The physiological functions of Cygb and Ngb remain to be determined; however, current data suggest that both proteins have a significant role in cytoprotection in hypoxic and genotoxic conditions. Cytoglobin and Ngb are distinct from their better-known counterparts, hemoglobin (Hb) and myoglobin (Mb), in several structural features. First, in the absence of an external ligand, the sixth coordination site of the ...


Regulation Of Juvenile Hormone Synthesis By 20-Hydroxyecdysone In The Yellow-Fever Mosquito, Aedes Aegypti, Maria Areiza May 2018

Regulation Of Juvenile Hormone Synthesis By 20-Hydroxyecdysone In The Yellow-Fever Mosquito, Aedes Aegypti, Maria Areiza

FIU Electronic Theses and Dissertations

In Aedes aegypti, development and reproduction are regulated by juvenile hormone III (JH). This master regulatory hormone is synthesized by the corpora allata (CA), a pair of endocrine glands with neural connections to the brain. JH titers are largely determined by the rate of biosynthetic activity of the CA and are regulated by inhibitory and stimulatory factors. Like JH, the ecdysteroid 20-hydroxyecdysone (20E) is a key hormonal regulator and has been proposed as an allatoregulator in other insects. However, its part in the regulation of JH biosynthesis of mosquitoes was unknown. The specific aims of this dissertation were to (1 ...


Structure And Mechanism Of Mycobacterial Topoisomerase I, Nan Cao May 2018

Structure And Mechanism Of Mycobacterial Topoisomerase I, Nan Cao

FIU Electronic Theses and Dissertations

The enzyme DNA topoisomerase I is an essential enzyme that plays an important role in eukaryotic and prokaryotic cellular processes such as DNA replication, transcription, recombination and repair. Mycobacterium tuberculosistopoisomerase I (MtTOP1) is a validated drug target for antituberculosis treatment. Mycobacterial topoisomerase I regulates the topological constraints in chromosomes and helps in maintaining the growth of mycobacteria. The N- terminal domain (NTD) of mycobacterial topoisomerase I contains conserved catalytic domains that along with the active site Tyrosine are involved in cleaving and rejoining a single strand of DNA. Magnesium is required in DNA cleavage activity of type IA topoisomerases ...


Trinucleotide Repeat Instability Modulated By Dna Repair Enzymes And Cofactors, Yaou Ren May 2018

Trinucleotide Repeat Instability Modulated By Dna Repair Enzymes And Cofactors, Yaou Ren

FIU Electronic Theses and Dissertations

Trinucleotide repeat (TNR) instability including repeat expansions and repeat deletions is the cause of more than 40 inherited incurable neurodegenerative diseases and cancer. TNR instability is associated with DNA damage and base excision repair (BER). In this dissertation research, we explored the mechanisms of BER-mediated TNR instability via biochemical analysis of the BER protein activities, DNA structures, protein-protein interaction, and protein-DNA interaction by reconstructing BER in vitro using synthesized oligonucleotide TNR substrates and purified human proteins. First, we evaluated a germline DNA polymerase β (pol β) polymorphic variant, pol βR137Q, in leading TNR instability-mediated cancers or neurodegenerative diseases. We find ...


The Cyclodextrin-Perfluorinated Surfactant Host-Guest Complex: Fundamental Studies For Potential Environmental Remediation And Therapeutic Applications, Mary J. Errico May 2018

The Cyclodextrin-Perfluorinated Surfactant Host-Guest Complex: Fundamental Studies For Potential Environmental Remediation And Therapeutic Applications, Mary J. Errico

FIU Electronic Theses and Dissertations

Perfluoroalkyl substances (PFASs) are contaminants of emerging concern, and have been detected in drinking water, wildlife, humans, and the environment. Cyclodextrins (CDs), cyclic sugars composed of glucose monomers, are proposed as a potential remediation strategy. CDs can form host-guest complexes with hydrophobic molecules; this complexation could be capitalized on for PFAS removal and sequestration. These dissertation projects aim to study the fundamental host-guest interactions between a variety of PFASs and CDs for eventual applications in environmental and biological remediation. 1D and 2D Nuclear magnetic resonance (NMR) spectroscopic methods were employed to determine the strength, dynamics, and structure of the CD ...


Conformational Dynamics Of Biomolecules By Trapped Ion Mobility Spectrometry Dynamics, Juan Camilo Molano-Arévalo Apr 2018

Conformational Dynamics Of Biomolecules By Trapped Ion Mobility Spectrometry Dynamics, Juan Camilo Molano-Arévalo

FIU Electronic Theses and Dissertations

One of the main goals in structural biology is to understand the folding mechanisms and three-dimensional structure of biomolecules. Many biomolecular systems adopt multiple structures as a function of their microenvironment, which makes them difficult to be characterized by traditional structural biology tools (e.g., NMR, X-ray crystallography). As an alternative, complementary tools that can capture and sample multiple conformations needed to be developed. In the present work, we pioneered the application of a new variant of ion mobility spectrometry, trapped ion mobility spectrometry (TIMS), which provides high mobility resolving power and the possibility to study kinetically trapped intermediates as ...


Understanding The Functional Group-Dependent Self-Assembly And Cellular Entry Of Cationic Conjugated Polymer Nanoparticles, Prakash Manandhar Mar 2018

Understanding The Functional Group-Dependent Self-Assembly And Cellular Entry Of Cationic Conjugated Polymer Nanoparticles, Prakash Manandhar

FIU Electronic Theses and Dissertations

Highly fluorescent conjugated polymers (CPs) are an important class of biomaterials used for various biological applications including labelling, sensing, and delivery of biological substances. Synthetic versatility and tunable emission make CPs a superior class of biomaterials. Understanding the structure-function relationship of CPs plays a vital role in designing high performing biomaterials. The cationic CPs are self-assembled to conjugated polymer nanoparticles (CPNs) in an aqueous environment due to their amphiphilicity. The physical and biophysical properties of CPNs are highly dependent on the chemical functionality and backbone structure of CPs. Modulation of the surface property and backbone structure of CPNs play an ...


The Study Of Tissue-Specific Dna Methylation As A Method For The Epigenetic Discrimination Of Forensic Samples, Joana Ap Antunes Nov 2017

The Study Of Tissue-Specific Dna Methylation As A Method For The Epigenetic Discrimination Of Forensic Samples, Joana Ap Antunes

FIU Electronic Theses and Dissertations

In forensic sciences, the serological methods used to determine which body fluid was collected from the crime scene are merely presumptive or labor intensive since they rely on protein detection or on microscopic identification of cells. Given that certain forensic cases may need the precise identification of a body fluid to determine criminal contact, such is the example of a suspected sexual assault of a minor; certainty in the body fluid of origin may depict a precise picture of the events. The identification of loci that show differences in methylation according to the tissue of origin can aid forensic analysts ...


Drug Candidate Discovery: Targeting Bacterial Topoisomerase I Enzymes For Novel Antibiotic Leads, Shayna Sandhaus Nov 2017

Drug Candidate Discovery: Targeting Bacterial Topoisomerase I Enzymes For Novel Antibiotic Leads, Shayna Sandhaus

FIU Electronic Theses and Dissertations

Multi-drug resistance in bacterial pathogens has become a global health crisis. Each year, millions of people worldwide are infected with bacterial strains that are resistant to currently available antibiotics. Diseases such as tuberculosis, pneumonia, and gonorrhea have become increasingly more difficult to treat. It is essential that novel drugs and cellular targets be identified in order to treat this resistance. Bacterial topoisomerase IA is a novel drug target that is essential for cellular growth. As it has never been targeted by existing antibiotics, it is an attractive target. Topoisomerase IA is responsible for relieving torsional strain on DNA by relaxing ...


Epigenetic Instability Induced By Dna Base Lesion Via Dna Base Excision Repair, Zhongliang Jiang Sep 2017

Epigenetic Instability Induced By Dna Base Lesion Via Dna Base Excision Repair, Zhongliang Jiang

FIU Electronic Theses and Dissertations

DNA damage can cause genome instability, which may lead to human cancer. The most common form of DNA damage is DNA base damage, which is efficiently repaired by DNA base excision repair (BER). Thus BER is the major DNA repair pathway that maintains the stability of the genome. On the other hand, BER mediates DNA demethylation that can occur on the promoter region of important tumor suppressor genes such as Breast Cancer 1 (BRCA1) gene that is also involved in prevention and development of cancer. In this study, employing cell-based and in vitro biochemical approaches along with bisulfite DNA sequencing ...


The Effect Of Target-Specific Biomolecules In Breast Cancer, Mohannad Garoub Jun 2017

The Effect Of Target-Specific Biomolecules In Breast Cancer, Mohannad Garoub

FIU Electronic Theses and Dissertations

Cancer is the second leading cause of mortality in the United States and the World, therefore, early effective prevention, diagnosis, and therapy is needed. Estrogens play a major role in the initiation and progression of breast cancer. Elevated lifetime exposure to estrogens is associated with an increased risk of developing breast cancer. Estrogens through influencing mitochondria contribute to estrogen induced breast carcinogenesis; however, the exact mitochondrial mechanisms underlying the estrogen carcinogenic effect in breast tissue are not clearly understood. For this dissertation, the mitotoxic and cytotoxic effects of triphenylphosphonium cation (TPP) and Origanum majorana organic extract (OME) as well as ...


Protein-Protein Interactions Of Bacterial Topoisomerase I, Srikanth Banda Jun 2017

Protein-Protein Interactions Of Bacterial Topoisomerase I, Srikanth Banda

FIU Electronic Theses and Dissertations

Protein-protein interactions (PPIs) are essential features of cellular processes including DNA replication, transcription, translation, recombination, and repair. In my study, the protein interactions of bacterial DNA topoisomerase I, an essential enzyme, were investigated. The topoisomerase I in bacteria relaxes excess negative supercoiling on DNA and maintains genomic stability. Investigating the PPI network of DNA topoisomerase I can further our understanding of the various functional roles of this enzyme. My study is focused on topoisomerase I of Escherichia coli and Mycobacterium smegmatis. Firstly, we have explored the biochemical mechanisms for an interaction between RNA Polymerase, and topoisomerase I in E. coli ...


Studies Of Nε-Lysine Acetylation Modification On Escherichia Coli Topoisomerase I, Qingxuan Zhou Jun 2017

Studies Of Nε-Lysine Acetylation Modification On Escherichia Coli Topoisomerase I, Qingxuan Zhou

FIU Electronic Theses and Dissertations

Escherichia coli topoisomerase I (TopA), a regulator of global and local DNA supercoiling, is modified by Nε-Lysine acetylation. The sirtuin protein deacetylase CobB can reverse both enzymatic and non-enzymatic lysine acetylation modifications. Here, we explored the effect of lysine acetylation on E. coli topoisomerase I through analysis of TopA relaxation activity and protein expression in cell extract of wild-type and a ΔcobB mutant strains. We showed that the absence of deacetylase CobB in a ΔcobB mutant reduced intracellular TopA relaxation activity while elevating TopA expression and topA gene transcripts levels. Acetyl phosphate mediated lysine acetylation decreased the activity ...


Biochemical Characterization Of Arsi: A Novel C-As Lyase For Degradation Of Environmental Organoarsenicals, Shashank Suryakant Pawitwar Jun 2017

Biochemical Characterization Of Arsi: A Novel C-As Lyase For Degradation Of Environmental Organoarsenicals, Shashank Suryakant Pawitwar

FIU Electronic Theses and Dissertations

Organoarsenicals such as methylarsenical methylarsenate (MAs(V)) and aromatic arsenicals including roxarsone (4-hydroxy-3-nitrophenylarsenate or Rox(V)) have been extensively used as an herbicide and growth enhancers in animal husbandry, respectively. They undergo environmental degradation to more toxic inorganic arsenite (As(III)) that contaminates crops and drinking water. We previously identified a bacterial gene (arsI) responsible for aerobic MAs(III) demethylation. The gene product, ArsI, is a Fe(II)-dependent extradiol dioxygenase that cleaves the carbon-arsenic (C-As) bond in MAs(III) and trivalent aromatic arsenicals. The objective of this study was to elucidate the ArsI mechanism. Using isothermal titration calorimetry, we ...


Thermally-Assisted Acoustofluidic Separation For Bioanalytical Applications, Ata Dolatmoradi Jun 2017

Thermally-Assisted Acoustofluidic Separation For Bioanalytical Applications, Ata Dolatmoradi

FIU Electronic Theses and Dissertations

Changes in the biomechanical properties of cells accompanying the development of various pathological conditions have been increasingly reported as biomarkers for various diseases and as a predictor of disease progression stages. For instance, cancer cells have been found to be less stiff compared to their healthy counterparts due to the proteomic and lipidomic dysregulations conferred by the underlying pathology. The separation and selective recovery of cells or extracellular vesicles secreted from such cells that have undergone these changes have been suggested to be of diagnostic and prognostic value.

This dissertation first describes the implementation of a stiffness-based separation of phosphatidylcholine-based ...


Laurel Wilt Disease: Early Detection Through Canine Olfaction And "Omics" Insights Into Disease Progression, Julian L. Mendel Jun 2017

Laurel Wilt Disease: Early Detection Through Canine Olfaction And "Omics" Insights Into Disease Progression, Julian L. Mendel

FIU Electronic Theses and Dissertations

Laurel wilt disease is a vascular wilt affecting the xylem and water conductivity in trees belonging to the family Lauraceae. The disease was introduced by an invasive species of ambrosia beetle, Xyleborus glabratus. The beetle, together with its newly described fungal symbiont Raffaelea lauricola (pathogenic to host trees), has lead to the devastation and destruction of over 300 million wild redbay trees in southeastern forests. Ambrosia beetles make up a very unique clade of beetle and share a co-evolved obligatory mutualistic relationship with their partner fungi. Rather than consuming host tree material, the beetles excavate galleries or canals within them ...


Transcriptomic And Epigenetic Responses To Environmental Stress In Marine Bivalves With A Focus On Harmful Algal Blooms, Maria Victoria Suarez Ulloa Jun 2017

Transcriptomic And Epigenetic Responses To Environmental Stress In Marine Bivalves With A Focus On Harmful Algal Blooms, Maria Victoria Suarez Ulloa

FIU Electronic Theses and Dissertations

Global change poses new threats for life in the oceans forcing marine organisms to respond through molecular acclimatory and adaptive strategies. Although bivalve molluscs are particularly tolerant and resilient to environmental stress, they must now face the challenge of more frequent and severe Harmful Algal Blooms (HABs) episodes. These massive outbreaks of microalgae produce toxins that accumulate in the tissues of these filter-feeder organisms, causing changes in their gene expression profiles, which in turn modify their phenotype in order to maintain homeostasis. Such modifications in gene expression are modulated by epigenetic mechanisms elicited by specific environmental stimuli, laying the foundations ...


Thermodynamics And Kinetics Of Ligand Photodissociation In Heme Proteins And Formation Of Dna I-Motif, David S. Butcher Mar 2017

Thermodynamics And Kinetics Of Ligand Photodissociation In Heme Proteins And Formation Of Dna I-Motif, David S. Butcher

FIU Electronic Theses and Dissertations

Heme proteins carry out a diverse array of functions in vivo while maintaining a well-conserved 3-over-3 α-helical structure. Human hemoglobin (Hb) is well-known for its oxygen transport function. Type 1 non-symbiotic hemoglobins (nsHb1) in plants and bacterial flavohemoglobins (fHb) from a variety of bacterial species have been predicted to carry out a nitric oxide dioxygenase function. In nsHb1 and fHb this function has been linked to protection from nitrosative stress. Herein, I combine photoacoustic calorimetry (PAC), transient absorption spectroscopy (TA), and classical molecular dynamics (cMD) simulations to characterize molecular mechanism of diatomic ligand interactions with a hexa-coordinate globin from plant ...


Enzyme Catalyzed And Ultrasound Assisted Transformation Of Selected Pollutants, Yi Tan Feb 2017

Enzyme Catalyzed And Ultrasound Assisted Transformation Of Selected Pollutants, Yi Tan

FIU Electronic Theses and Dissertations

The widespread use of synthetic drugs and as feed additives has resulted in the release of large amounts of biologically active chemicals into the environment. Exposure to environmentally relevant concentrations of chemicals can have severe effects on human health. Therefore, effective degradation of these synthetic, biologically active compounds is of paramount importance.

Diphenhydramine (DPH) has been selected as a target compound for ultrasound remediation. The results demonstrated that ultrasound-induced degradation has potential applications in managing aqueous media contaminated with DPH.

Atorvastatin and roxarsone have been selected as representative substrates for chloroperoxidase (CPO) catalyzed transformation of pollutants. These studies demonstrate atorvastatin ...


Design And Synthesis Of Novel Azasteroids And Pseudoazulenyl Nitrones, Nagaraju Birudukota Dec 2016

Design And Synthesis Of Novel Azasteroids And Pseudoazulenyl Nitrones, Nagaraju Birudukota

FIU Electronic Theses and Dissertations

Steroids are one of the essential classes of bioactive compounds and are involved in many biological functions which include their role as signaling compounds, the alteration of membrane fluidity and the regulation of a variety of metabolic processes. In order to identify novel compounds with beneficial pharmacological action, the synthesis of modified steroids is gaining much attention in recent years. Among those analogs, azasteroids are one of the most important classes which display a variety of biological activities, often free from undesirable side effects. The challenges in the synthesis of steroids, particularly azasteroids, and the potential of azasteroids as novel ...


Characterization Of Interaction Between Brevetoxin And Its Native Receptor And Identification Of The Role Of Brevetoxin In Karenia Brevis, Wei Chen Nov 2016

Characterization Of Interaction Between Brevetoxin And Its Native Receptor And Identification Of The Role Of Brevetoxin In Karenia Brevis, Wei Chen

FIU Electronic Theses and Dissertations

Algae are important to marine and fresh-water ecosystems. However, some species of algae are harmful or even toxic. They can consume oxygen or block sunlight that is essential for other organisms to live. Indeed, some algae blooms can produce toxins that damage the health of the environment, plants, animals, and humans. Harmful algal blooms (HABs) which are often more green, brown, or dark-colored than red have spread along the coastlines and in the surface waters of the United States. Therefore, scientists are making great efforts to study HABs in order to maintain human and ecosystem health.

Karenia brevis, the major ...


Screening Of Plants For Antibacterial Properties: Growth Inhibition Of Staphylococcus Aureus By Artemisia Tridentata, Steven Ross Eichelbaum Nov 2016

Screening Of Plants For Antibacterial Properties: Growth Inhibition Of Staphylococcus Aureus By Artemisia Tridentata, Steven Ross Eichelbaum

FIU Electronic Theses and Dissertations

Drug-resistant pathogenic and opportunistic bacteria are increasing in occurrence and prevalence, and pose a dangerous threat to human health. In the search for novel antibiotics with which to combat this threat, plants, specifically those used in traditional medicine with ascribed antibacterial properties, offer a promising and potentially vast source of such therapeutic compounds. The purpose of this study was therefore to screen chemical extracts created from various plant species for antibacterial properties versus pathogenic bacterial species. In the course of these antibacterial assays, we successfully identified a methanol extract derived from Artemisia tridentata tridentata plant material as capable of inhibiting ...


Microbial Functional Diversity And The Associated Biogeochemical Interactions Across Miami-Dade County, Florida Soils, Priyanka Kushwaha Nov 2016

Microbial Functional Diversity And The Associated Biogeochemical Interactions Across Miami-Dade County, Florida Soils, Priyanka Kushwaha

FIU Electronic Theses and Dissertations

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 ...


Trinucleotide Repeat Instability Is Modulated By Dna Base Lesions And Dna Base Excision Repair, Jill M. Beaver Sep 2016

Trinucleotide Repeat Instability Is Modulated By Dna Base Lesions And Dna Base Excision Repair, Jill M. Beaver

FIU Electronic Theses and Dissertations

Trinucleotide repeat (TNR) expansions are the cause of over 40 human neurodegenerative diseases, and are linked to DNA damage and base excision repair (BER). We explored the role of DNA damage and BER in modulating TNR instability through analysis of DNA structures, BER protein activities, and reconstitution of repair using human BER proteins and synthesized DNA containing various types of damage. We show that DNA damage and BER can modulate TNR expansions by promoting removal of a TNR hairpin through coordinated activities of BER proteins and cofactors. We found that during repair in a TNR hairpin, coordination between the 5 ...


Dna Aptamer Confirmation And Utilization For The Cyanotoxin, Cylindrospermopsin, Diane M. Catlin Jul 2016

Dna Aptamer Confirmation And Utilization For The Cyanotoxin, Cylindrospermopsin, Diane M. Catlin

FIU Electronic Theses and Dissertations

Cyanotoxins are posing an increasing threat to the health of humans and wildlife. Cylindrospermopsin is a cyanotoxin that occurs in warm climates and is harmful when ingested. The toxic effects of CYN can affect multiple organ systems. The effects, coupled with the evidence of a mass contamination of a water supply in Australia, prove that CYN needs to be investigated further.

Aptamers have become a desirable method for detection of CYN as a result of an aptamer’s high specificity and the ability to scale up experiments. Aptamers have been designed to bind with a variety of targets, including cyanotoxins ...


Regulation Of Particle Uptake By Pp2a/B56 And Lkb1 In Dictyostelium Discoideum, Mujataba Rahiman Sharief Jul 2016

Regulation Of Particle Uptake By Pp2a/B56 And Lkb1 In Dictyostelium Discoideum, Mujataba Rahiman Sharief

FIU Electronic Theses and Dissertations

Dictyostelium discoideum is a soil dwelling amoeba which has been widely used as a model organism to study cellular processes such as signal transduction, chemotaxis, endocytosis and exocytosis. The process of phagocytosis in Dicytostelium is largely comparable to that of neutrophils and macrophages in the mammalian system. Neutrophils and macrophages are cells of the innate immune system and they engulf infectious bacteria through phagocytosis. Dictyostelium cells uptake yeast and bacteria for their nutrition through phagocytosis, which is an actin dependent mechanism and is a target of multiple signaling inputs. Recent studies have uncovered different proteins involved in the signaling of ...