Biochemistry, Biophysics, and Structural Biology Commons^™

Discovery & Born-Digital Archiving: Open Source Systems For Preservation And Access, L. Bryan Cooper, Margarita Perez-Martinez

Works of the FIU Libraries

The Everglades Explorer (EE) portal at http://ee.fiu.edu continues to evolve with the addition of the Internet Archive's Archive-It, and future planned alignment with the Digital Public Library of America (DPLA). The reasons for the development of the portal continue to exist, as originally perceived four years ago. Adaptations to ongoing change and system testing continues, and the use of Archive-It has broad institutional potential beyond EE. Cross-walking skills continue to grown, and will benefit future syndication and discovery system integration. The metadata normalization and harmonization will help save time for the end-user. Preservation and access to learning and research …

A Mechanism Of Glucose Tolerance And Stimulation Of Gh1 Β-Glucosidases, Yang Yang, Xinxin Zhang, Qiang Yin, Wei Fang, Zemin Fang, Xiaotang Wang, Xuecheng Zhang, Yazhong Xiao

Department of Chemistry and Biochemistry

β-Glucosidases are enzymes that hydrolyze β-glycosidic bonds to release non-reducing terminal glucosyl residues from glycosides and oligosaccharides, and thus have significant application potential in industries. However, most β-glucosidases are feedback inhibited by the glucose product, which restricts their application. Remarkably, some β-glucosidases of the glycoside hydrolase (GH) 1 family are tolerant to or even stimulated by glucose. Elucidation of the mechanisms of glucose tolerance and stimulation of the GH1 β-glucosidases will be crucial to improve their application through enzyme engineering. In this study, by comparing the primary and tertiary structures of two GH1 β-glucosidases with distinct glucose dependence, some putative …

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 procedures, it …

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 …

Ap Endonuclease 1 Prevents Trinucleotide Repeat Expansion Via A Novel Mechanism During Base Excision Repair, Jill M. Beaver, Yanhao Lai, Meng Xu, Astrid H. Casin, Eduardo E. Laverde, Yuan Liu

Department of Chemistry and Biochemistry

Base excision repair (BER) of an oxidized base within a trinucleotide repeat (TNR) tract can lead to TNR expansions that are associated with over 40 human neurodegenerative diseases. This occurs as a result of DNA secondary structures such as hairpins formed during repair. We have previously shown that BER in a TNR hairpin loop can lead to removal of the hairpin, attenuating or preventing TNR expansions. Here, we further provide the first evidence that AP endonuclease 1 (APE1) prevented TNR expansions via its 3′-5′ exonuclease activity and stimulatory effect on DNA ligation during BER in a hairpin loop. Coordinating with …

Linking Old Librarianship To New: Aligning 5-Steps Of The Innovator's Dna In Creating Thematic Discovery Systems For The Everglades, L. Bryan Cooper, Margarita Perez Martinez

Works of the FIU Libraries

This poster presentation from the May 2015 Florida Library Association Conference, along with the Everglades Explorer discovery portal at http://ee.fiu.edu, demonstrates how traditional bibliographic and curatorial principles can be applied to: 1) selection, cross-walking and aggregation of metadata linking end-users to wide-spread digital resources from multiple silos; 2) harvesting of select PDFs, HTML and media for web archiving and access; 3) selection of CMS domains, sub-domains and folders for targeted searching using an API.

Choosing content for this discovery portal is comparable to past scholarly practice of creating and publishing subject bibliographies, except metadata and data are housed in …

Oroxylin A Promotes Pten-Mediated Negative Regulation Of Mdm2 Transcription Via Sirt3-Mediated Deacetylation To Stabilize P53 And Inhibit Glycolysis In Wt-P53 Cancer Cells, Kai Zhao, Yuxin Zhou, Chen Qiao, Ting Ni, Zhiyu Li, Xiaotang Wang, Qinglong Guo, Na Lu, Libin Wei

Department of Chemistry and Biochemistry

Introduction

p53 plays important roles in regulating the metabolic reprogramming of cancer, such as aerobic glycolysis. Oroxylin A is a natural active flavonoid with strong anticancer effects both in vitro and in vivo.

Methods

wt-p53 (MCF-7 and HCT116 cells) cancer cells and p53-null H1299 cancer cells were used. The glucose uptake and lactate production were analyzed using Lactic Acid production Detection kit and the Amplex Red Glucose Assay Kit. Then, the protein levels and RNA levels of p53, mouse double minute 2 (MDM2), and p53-targeted glycolytic enzymes were quantified using Western blotting and quantitative polymerase chain reaction (PCR), respectively. …

Inhibition Of Zn(Ii) Binding Type Ia Topoisomerases By Organomercury Compounds And Hg(Ii), Bokun Cheng, Thirunavukkarasu Annamalai, Shayna Sandhaus, Priyanka Bansod, Yuk-Ching Tse-Dinh

Department of Chemistry and Biochemistry

Type IA topoisomerase activities are essential for resolving DNA topological barriers via an enzyme-mediated transient single strand DNA break. Accumulation of topoisomerase DNA cleavage product can lead to cell death or genomic rearrangement. Many antibacterial and anticancer drugs act as topoisomerase poison inhibitors that form stabilized ternary complexes with the topoisomerase covalent intermediate, so it is desirable to identify such inhibitors for type IA topoisomerases. Here we report that organomercury compounds were identified during a fluorescence based screening of the NIH diversity set of small molecules for topoisomerase inhibitors that can increase the DNA cleavage product of Yersinia pestis topoisomerase …

The Effect Of Sample And Sample Matrix On Dna Processing: Mechanisms For The Detection And Management Of Inhibition In Forensic Samples, Lilliana I. Moreno

FIU Electronic Theses and Dissertations

The presence of inhibitory substances in biological forensic samples has, and continues to affect the quality of the data generated following DNA typing processes. Although the chemistries used during the procedures have been enhanced to mitigate the effects of these deleterious compounds, some challenges remain. Inhibitors can be components of the samples, the substrate where samples were deposited or chemical(s) associated to the DNA purification step. Therefore, a thorough understanding of the extraction processes and their ability to handle the various types of inhibitory substances can help define the best analytical processing for any given sample. A series of experiments …

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 …

A Rapid And Sensitive High-Throughput Screening Method To Identify Compounds Targeting Protein–Nucleic Acids Interactions, Nicole Alonso, Roboan Guillen

Undergraduate Research at FIU (URFIU) Conference

DNA-binding and RNA-binding proteins are usually considered ‘undruggable’ partly due to the lack of an efficient method to identify inhibitors from existing small molecule repositories. Here we report a rapid and sensitive high-throughput screening approach to identify compounds targeting protein–nucleic acids interactions based on protein–DNA or protein–RNA interaction enzyme-linked immunosorbent assays (PDI-ELISA or PRI-ELISA). We validated the PDI-ELISA method using the mammalian highmobility- group protein AT-hook 2 (HMGA2) as the protein of interest and netropsin as the inhibitor of HMGA2–DNA interactions. With this method we successfully identified several inhibitors and an activator for HMGA2–DNA interactions from a collection of 29 …

Conformational Kinetics Study Of Mp-11 Using Tims-Ms And Molecular Dynamics, Christopher Harrilal, Jaroslava Miksovska, Emily R. Schenk

Undergraduate Research at FIU (URFIU) Conference

In the present work, we studied the conformational kinetics of microperoxidase 11 (MP-11), a digest fragment of cytochrome C that contains 11 amino acids with a covalently attached heme group. In particular, a novel technique recently developed at FIU in collaboration with Bruker Daltonics Inc. combined with theoretical calculation was used for the characterization of MP- 11 conformational space [1-3]. Accurate ion-neutral collision cross sections were measured for all MP-11 generated charge states. Since MP-11 (like cytochrome C) undergoes conformational changes as a function of the solvent state, MP-11 ions were produced by electrospray ionization (ESI) in order to preserve …

Modification Of Purine And Pyrimidine Nucleosides By Direct C-H Bond Activation, Yong Liang, Stanislaw F. Wnuk

Department of Chemistry and Biochemistry

Transition metal-catalyzed modifications of the activated heterocyclic bases of nucleosides as well as DNA or RNA fragments employing traditional cross-coupling methods have been well-established in nucleic acid chemistry. This review covers advances in the area of cross-coupling reactions in which nucleosides are functionalized via direct activation of the C8-H bond in purine and the C5-H or C6-H bond in uracil bases. The review focuses on Pd/Cu-catalyzed couplings between unactivated nucleoside bases with aryl halides. It also discusses cross-dehydrogenative arylations and alkenylations as well as other reactions used for modification of nucleoside bases that avoid the use of organometallic precursors and …

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 …

A Rapid And Sensitive High-Throughput Screening Method To Identify Compounds Targeting Protein-Nucleic Acids Interactions, Nicole Alonso, Roboan Guillen, Jeremy W. Chambers, Fenfei Leng

Department of Chemistry and Biochemistry

DNA-binding and RNA-binding proteins are usually considered ‘undruggable’ partly due to the lack of an efficient method to identify inhibitors from existing small molecule repositories. Here we report a rapid and sensitive high-throughput screening approach to identify compounds targeting protein– nucleic acids interactions based on protein–DNA or protein–RNA interaction enzyme-linked immunosorbent assays (PDI-ELISA or PRI-ELISA). We validated the PDI-ELISA method using the mammalian highmobility- group protein AT-hook 2 (HMGA2) as the protein of interest and netropsin as the inhibitor of HMGA2–DNA interactions. With this method we successfully identified several inhibitors and an activator for HMGA2–DNA interactions from a collection of …

Selective Reduction Of Cr(Vi) In Chromium, Copper And Arsenic (Cca) Mixed Waste Streams Using Uv/Tio2 Photocatalysis, Shan Zheng, Wenjun Jiang, Mamun Rashid, Yong Cai, Dionysios D. Dionysiou, Kevin E. O'Shea

Department of Chemistry and Biochemistry

The highly toxic Cr(VI) is a critical component in the Chromated Copper Arsenate (CCA) formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI) to less toxic Cr(III) in the presence of arsenate, As(V), and copper, Cu(II). The rapid conversion of Cr(VI) to Cr(III) during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis …

Theoretical Investigation Of Intra- And Inter-Cellular Spatiotemporal Calcium Patterns In Microcirculation, Jaimit B. Parikh

FIU Electronic Theses and Dissertations

Microcirculatory vessels are lined by endothelial cells (ECs) which are surrounded by a single or multiple layer of smooth muscle cells (SMCs). Spontaneous and agonist induced spatiotemporal calcium (Ca²⁺) events are generated in ECs and SMCs, and regulated by complex bi-directional signaling between the two layers which ultimately determines the vessel tone. The contractile state of microcirculatory vessels is an important factor in the determination of vascular resistance, blood flow and blood pressure. This dissertation presents theoretical insights into some of the important and currently unresolved phenomena in microvascular tone regulation. Compartmental and continuum models of isolated EC …