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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 ...


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 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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


The Degradation Of Pharmaceutical Pollutants In Wastewater Catalyzed By Chloroperoxidase And The Construction Of Chloroperoxidase H105r Mutant, Qinghao He Jun 2016

The Degradation Of Pharmaceutical Pollutants In Wastewater Catalyzed By Chloroperoxidase And The Construction Of Chloroperoxidase H105r Mutant, Qinghao He

FIU Electronic Theses and Dissertations

Trace amounts of pharmaceuticals have been detected in water, from nanograms per liter to micrograms per liter, and have a negatively effect in the aquatic environment and an increased potential risk of drug poisoning for human and animals. In order to address the problem, drug degradation catalyzed by chloroperoxidase (CPO) has been investigated. CPO is a heme-containing glycoprotein secreted by the fungus, Caldariomyces fumago, it catalyzes two major types of oxidations, two one-electron oxidations as catalyzed by most peroxidases and two-electron oxidations which are rare for conventional peroxidases.

Five common drugs from a variety of classes which were persistent in ...


Conformational Dynamics And Stability Associated With Magnesium Or Calcium Binding To Dream In The Regulation Of Interactions Between Dream And Dna Or Presenilins, Khoa Ngoc Pham Jun 2016

Conformational Dynamics And Stability Associated With Magnesium Or Calcium Binding To Dream In The Regulation Of Interactions Between Dream And Dna Or Presenilins, Khoa Ngoc Pham

FIU Electronic Theses and Dissertations

Downstream regulatory element antagonist modulator (DREAM) is involved in various interactions with targets both inside and outside of the nucleus. In the cytoplasm, DREAM interacts with the C-terminal fragments of presenilins to facilitate the production of β-amyloid plaques in Alzheimer’s disease. In the nucleus, Ca2+ free DREAM directly binds to specific downstream regulatory elements of prodynorphin/c-fos gene to repress the gene transcription in pain modulation. These interactions are regulated by Ca2+ and/or Mg2+ association at the EF-hands in DREAM. Therefore, understanding the conformational dynamics and stability associated with Ca2+ and/or Mg ...


Extraction, Purification And Partial Characterization Of A Carotenoid Binding Protein (Cbp) From The Epidermis Of The Monarch Butterfly Larvae (Danaus Plexippus), Nan Fang Jun 2016

Extraction, Purification And Partial Characterization Of A Carotenoid Binding Protein (Cbp) From The Epidermis Of The Monarch Butterfly Larvae (Danaus Plexippus), Nan Fang

FIU Electronic Theses and Dissertations

This dissertation describes the purification and partial characterization of CBP from the epidermis of the monarch butterfly larvae (Danaus plexippus). A yellow protein-carotenoid complex was extracted from the yellow pigmented epidermal tissue from monarch butterfly larvae by homogenization. Additional steps in the purification process included differential precipitation with ammonium sulfate, cation and anion chromatography, and lastly size exclusion chromatography. Polyacrylamide gel electrophoresis demonstrates that a single protein was isolated (M-LBP) having a ~60 kDa molecular weight, the value has subsequently been confirmed by HR-tandem MS. Lutein is the sole carotenoid bound by M-LBP with a stoichiometry of the binding of ...


Protein-Ligand Interactions And Allosteric Regulation Of Activity In Dream Protein, Walter G. Gonzalez Mar 2016

Protein-Ligand Interactions And Allosteric Regulation Of Activity In Dream Protein, Walter G. Gonzalez

FIU Electronic Theses and Dissertations

Downstream regulatory antagonist modulator (DREAM) is a calcium sensing protein that co-assembles with KV4 potassium channels to regulate ion currents as well as with DNA in the nucleus, where it regulates gene expression. The interaction of DREAM with A-type KV4 channels and DNA has been shown to regulate neuronal signaling, pain sensing, and memory retention. The role of DREAM in modulation of pain, onset of Alzheimer’s disease, and cardiac pacemaking has set this protein as a novel therapeutic target. Moreover, previous results have shown a Ca2+ dependent interaction between DREAM and KV4 ...


Conjugated Polymer-Based Biomaterials Through Controlled Self-Assembly, Megan Twomey Mar 2016

Conjugated Polymer-Based Biomaterials Through Controlled Self-Assembly, Megan Twomey

FIU Electronic Theses and Dissertations

Synthetic polymeric materials have gained significant use as biological materials (biomaterials) in biomedical and pharmaceutical applications. As a result, a demand for well-defined polymers with tunable properties has emerged. The synthetic versatility of polymeric biomaterials allows the opportunity to understand the structure-property relationship of materials and their cellular interactions. A novel class of polymeric biomaterials are conjugated polymers (CPs), which possess desirable physicochemical and excellent photophysical properties, including inherent fluorescence. The synthetic versatility of CPs allows easy modification of the conjugated backbone to tune emission and side chain structures to adjust biocompatibility through increased water solubility, controlled biodegradability, and incorporation ...


The Influence Of The Proximal Thiolate Ligand And Hydrogen Bond Network Of The Proximal Helix On The Structural And Biochemical Properties Of Chloroperoxidase, Elena Shersher Mar 2016

The Influence Of The Proximal Thiolate Ligand And Hydrogen Bond Network Of The Proximal Helix On The Structural And Biochemical Properties Of Chloroperoxidase, Elena Shersher

FIU Electronic Theses and Dissertations

Chloroperoxidase (CPO) from Caldariomyces fumago is a versatile heme enzyme with great potential for environmental and pharmaceutical applications. It catalyzes a plethora of reactions including halogenation, dismutation, epoxidation, and oxidation. The diverse catalytic capabilities of CPO have long been attributed to the protein’s distinct active site that combines structural features of peroxidases and cytochromes P450. Particularly, the role of the axial thiolate ligand in CPO catalysis has been much debated. Furthermore, no data are available on the role of hydrogen bonding between Arg 26-Asn 37 and Ala 27-Asn 33 of the proximal helix in defining the structural and catalytic ...


Development Of A Maldi-Tof-Ms Method For The Analysis Of Cyanobacterial Neurotoxin Β-N-Methylamino-L-Alanine (Bmaa) In Search Of Bmaa Incorporation In Biological Samples, Laura M. Conklin Nov 2015

Development Of A Maldi-Tof-Ms Method For The Analysis Of Cyanobacterial Neurotoxin Β-N-Methylamino-L-Alanine (Bmaa) In Search Of Bmaa Incorporation In Biological Samples, Laura M. Conklin

FIU Electronic Theses and Dissertations

Beta-N-methylamino-L-alanine (BMAA) is a non-protein amino acid produced by many cyanobacteria, and thought to induce neurotoxic effects through excitotoxicity, contributing to neurodegenerative diseases such as Amyotrophic Lateral Sclerosis/Parkinsonism-dementia complex (ALS-PDC) and Alzheimer’s. The ubiquitous nature of cyanobacteria, and evidence of biomagnification through our food web, creates a dire need for the development of an analytical platform that will provide accurate identification and quantification of BMAA amounts in our ecosystem and potential food supply. The present study evaluated the ability of a MALDI-ToF-MS method to detect and quantify BMAA in a variety of biological matrices. Through validation ...


Characterization Of An Epoxide Hydrolase From The Florida Red Tide Dinoflagellate, Karenia Brevis, Pengfei Sun Jun 2015

Characterization Of An Epoxide Hydrolase From The Florida Red Tide Dinoflagellate, Karenia Brevis, Pengfei Sun

FIU Electronic Theses and Dissertations

Polyether compounds are a subgroup of natural products with regular occurrence of multiple C-O-C motifs. The biosynthetic origin of polycylic polethers has been studied and the majority of them are derived from polyketide or terpene pathways. Normally, the polycyclic polyethers can be divided into two groups based on their structural features: the first group features multiple rings that are interconnected by carbon-carbon single bond, which are produced by a biosynthetic cascade of exo epoxide-opening reactions; the other group has multiple fused cyclic ethers and are formed by an cascade of endo epoxide-opening reactions.

Karenia brevis (K. brevis) is known as ...


Redox Regulation Of Ras Proteins In Dictyostelium Discoideum, Boris Castillo Chabeco Mar 2015

Redox Regulation Of Ras Proteins In Dictyostelium Discoideum, Boris Castillo Chabeco

FIU Electronic Theses and Dissertations

Reactive oxygen species are a normal consequence of life in an aerobic environment. However when they deviate from the narrow permissible range in cells, oxidative damage can occur. Dictyostelium discoideum is a model organism ideal for the study of cell signaling events such as those affected by oxidative stress. It was previously shown that Ras signaling in Dictyostelium is affected by genetic inactivation of the antioxidant enzyme Superoxide dismutase C (SodC) and in vitro data suggests that the NKCD motif of Ras is the redox target of superoxide.

The main objective of this project was to determine the mechanism of ...


Multimode Analysis Of Nanoscale Biomolecular Interactions, Purushottam Babu Tiwari Feb 2015

Multimode Analysis Of Nanoscale Biomolecular Interactions, Purushottam Babu Tiwari

FIU Electronic Theses and Dissertations

Biomolecular interactions, including protein-protein, protein-DNA, and protein-ligand interactions, are of special importance in all biological systems. These interactions may occer during the loading of biomolecules to interfaces, the translocation of biomolecules through transmembrane protein pores, and the movement of biomolecules in a crowded intracellular environment. The molecular interaction of a protein with its binding partners is crucial in fundamental biological processes such as electron transfer, intracellular signal transmission and regulation, neuroprotective mechanisms, and regulation of DNA topology. In this dissertation, a customized surface plasmon resonance (SPR) has been optimized and new theoretical and label free experimental methods with related analytical ...