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Biochemistry Commons

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2019

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Articles 271 - 300 of 392

Full-Text Articles in Biochemistry

Dinitrogen Fixation Across Physico-Chemical Gradients Of The Eastern Tropical North Pacific Oxygen Deficient Zone, C. R. Selden, M. R. Mulholland, P.W. Bernhardt, B. Widner, A. Macías-Tapia, Q. Ji, A. Jayakumar Jan 2019

Dinitrogen Fixation Across Physico-Chemical Gradients Of The Eastern Tropical North Pacific Oxygen Deficient Zone, C. R. Selden, M. R. Mulholland, P.W. Bernhardt, B. Widner, A. Macías-Tapia, Q. Ji, A. Jayakumar

OES Faculty Publications

The Eastern Tropical North Pacific Ocean hosts one of the world's largest oceanic oxygen deficient zones (ODZs). Hot spots for reactive nitrogen (Nr) removal processes, ODZs generate conditions proposed to promote Nr inputs via dinitrogen (N2) fixation. In this study, we quantified N2 fixation rates by 15N tracer bioassay across oxygen, nutrient, and light gradients within and adjacent to the ODZ. Within subeuphotic oxygen‐deplete waters, N2 fixation was largely undetectable; however, addition of dissolved organic carbon stimulated N2 fixation in suboxic (μmol/kg O2) waters, suggesting that diazotroph communities are …


Ebullition Of Oxygen From Seagrasses Under Supersaturated Conditions, Matthew H. Long, Kevin Sutherland, Scott D. Wankel, David J. Burdige, Richard C. Zimmerman Jan 2019

Ebullition Of Oxygen From Seagrasses Under Supersaturated Conditions, Matthew H. Long, Kevin Sutherland, Scott D. Wankel, David J. Burdige, Richard C. Zimmerman

OES Faculty Publications

Gas ebullition from aquatic systems to the atmosphere represents a potentially important fraction of primary production that goes unquantified by measurements of dissolved gas concentrations. Although gas ebullition from photosynthetic surfaces has often been observed, it is rarely quantified. The resulting underestimation of photosynthetic activity may significantly bias the determination of ecosystem trophic status and estimated rates of biogeochemical cycling from in situ measures of dissolved oxygen. Here, we quantified gas ebullition rates in Zostera marina meadows in Virginia, U.S.A. using simple funnel traps and analyzed the oxygen concentration and isotopic composition of the captured gas. Maximum hourly rates of …


Effects And Mechanisms Of Anacardium Occidentale And Glochidion Zeylanicum Leaf Extracts On Neuroprotective, Neuritogenesis, Oxidative Stress Resistance And Anti-Aging Properties., Chatrawee Duangjan Jan 2019

Effects And Mechanisms Of Anacardium Occidentale And Glochidion Zeylanicum Leaf Extracts On Neuroprotective, Neuritogenesis, Oxidative Stress Resistance And Anti-Aging Properties., Chatrawee Duangjan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aging is the primary risk factor for most neurodegenerative diseases and can negatively affect the quality of life. Neurodegenerative diseases are linked to neuronal cell death and neurite outgrowth impairment that are often caused by oxidative stress. As people want to live longer and healthier, healthy nutrition has been increasingly received much attention in recent years. Several studies reported a positive correlation between antioxidants in foods and longevity. Natural products from food supplements and medicinal plants with antioxidant properties could be promising candidates for fighting against various aging-related diseases and promoting longevity. Leaf extracts from A. occidentale (AO) and G. …


Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu Jan 2019

Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu

Theses and Dissertations

In the United States, more than 130,000 people will be diagnosed with colorectal cancer (CRC) each year and an estimated 50,000 people will die from the disease. Standard of care (SOC) therapies for CRC combine multiple cytotoxic chemotherapeutic drugs. These combinations have varying degrees of effectiveness and can often result in significant patient morbidity. For second recurrence patients, the multi-kinase inhibitor, regorafenib, is an approved agent, but is often poorly tolerated at current doses. In the current study, we propose to develop therapeutic regime of combining agents with modest toxicity profiles: curcumin and sildenafil with regorafenib. Using clinically achievable enterohepatic …


Using Lipidomics To Characterize The Inflammatory Mechanisms In Sepsis And Pre-Eclampsia, Daniel Stephenson Jan 2019

Using Lipidomics To Characterize The Inflammatory Mechanisms In Sepsis And Pre-Eclampsia, Daniel Stephenson

Theses and Dissertations

Lipidomics, a rapidly developing field of study, focuses on the classification and quantitation of lipid species. Lipidomics has emerged in the forefront of scientific research due to the key roles that lipids play in metabolism, cancer, and disease. Using mass spectrometry as a tool for analysis, understanding the role eicosanoids and sphingolipids play has advanced rapidly. Being able to observe these small molecules in vivo has led to better understanding of several lipid-driven mechanisms and identification of eicosanoid and sphingolipid biomarkers in neurodegenerative disease, cancer, sepsis, wound healing, and pre-eclampsia. In the studies herein, we developed targeted mass spectrometric methods …


Biometal-Induced Structural Consequences Of Α-Synuclein – The Parkinson’S Disease Protein, Dinendra L. Abeyawardhane Jan 2019

Biometal-Induced Structural Consequences Of Α-Synuclein – The Parkinson’S Disease Protein, Dinendra L. Abeyawardhane

Theses and Dissertations

The pre-synaptic protein α-Synuclein (αS) is often linked to the pathology of Parkinson’s disease (PD), an age-related neurodegenerative disorder. Lewy bodies, the cytopathological hallmarks of PD, are found to be rich in aggregates of misfolded αS protein. Metal dyshomeostasis has also been linked to PD due to the accumulation of iron in the substantia nigra pars compacta, and diminished copper levels reported in this same region. Metal dyshomeostasis in the brain coupled with oxidative stress can enhance the aggregation of αS. Recently, it was confirmed that mammalian αS is universally acetylated at the N-terminus, a common post-translational modification in …


Analysis Of The Molecular Mechanisms Governing Fcγ Receptor Activation On The Surfaces Of Macrophages By Advanced Optical Microscopy, Elizabeth Michelle Bailey Jan 2019

Analysis Of The Molecular Mechanisms Governing Fcγ Receptor Activation On The Surfaces Of Macrophages By Advanced Optical Microscopy, Elizabeth Michelle Bailey

Electronic Theses and Dissertations

Therapeutic antibodies are achieving new levels of therapeutic success in treating cancers and immunological disorders by antibody engagement of Fc receptor-directed immune responses. Conversely, inhibiting autoantibody induced Fc receptor activation is an attractive approach to treat autoimmune diseases. Immunoglobulin G (IgG) antibodies are often the principal subclass used in therapeutic antibodies and associated with autoimmune pathologies because of their long circulation and potent effector functions, including activation of the Fcγ Receptor (FcγR). Thus, a thorough understanding of the FcγR activation is required to improve the efficacy of immunotherapies and to mitigate autoimmunities. It is well established that FcγR clustering is …


Case Studies Of Potential Reference Materials In Cultural Heritage Science, Heidi Kastenholz Jan 2019

Case Studies Of Potential Reference Materials In Cultural Heritage Science, Heidi Kastenholz

Undergraduate Honors Thesis Collection

The study of cultural heritage objects requires reference materials for comparison in order to determine the identity of chemical compounds in historically/culturally significant artifacts. The reference materials available today can be inaccurately labeled, can contain inauthentic compounds, or can simply be formed differently than what the labeled material should be. Utilizing the laboratory at the Indianapolis Museum of Art at Newfields, three case studies were conducted over three different potential reference materials in order to properly identify each of the three materials being focused on here. Based on the analysis, the labels for these materials often do not match the …


Measuring Trace Element Concentrations In Artiodactyl Cannonbones Using Portable X-Ray Fluorescence, Joshua L. Henderson Jan 2019

Measuring Trace Element Concentrations In Artiodactyl Cannonbones Using Portable X-Ray Fluorescence, Joshua L. Henderson

All Master's Theses

Artiodactyl bones are the most common faunal remains found in Washington prehistoric archaeology sites, but they are often too fragmented to accurately identify a family, genus, or species. Traditional faunal analysis can only organize unidentifiable bone fragments into size class, and chemical methods often require the destruction of bone samples. In this thesis research, I tested a new, nondestructive faunal analysis technique using portable X-ray fluorescence (pXRF) to measure trace element concentrations in comparative collection and archaeological bone samples. Using cannonbones from five different artiodactyl species, I collected trace element data from 50 comparative collection specimens and 18 archaeological specimens …


Effect Of Oil Palm Phenolics (Opp) On Pancreatic Cancer Cell Lines, Inaam Abdul Karim Jan 2019

Effect Of Oil Palm Phenolics (Opp) On Pancreatic Cancer Cell Lines, Inaam Abdul Karim

Wayne State University Theses

Pancreatic cancer (paca) is currently the fifth causes of cancer-related deaths in the United States. It’s an aggressive form of cancer with very low survival rates because of delayed diagnosis and limited treatment options. Gemcitabine is the chemotherapy drug that provides minimal benefits along with many side effects. The aim of this study was to examine the in vitro effects of oil palm phenolics (OPP) fraction-5, the water-soluble component of palm oil, in human pancreatic cancer cell models. Two pancreatic cancer cell lines (Panc-1 and BxPC-3) were categorized into control and treatment groups. The control group received cell culture media …


Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez Jan 2019

Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez

Chemistry Faculty Publications

Microplastics (or MPs; < 5 mm in size) pollution is largely unstudied in the Philippines. From an environmental sustainability standpoint, it is important to understand the characteristics, abundance, and environmental fate of plastic debris of various sizes, and these include microplastics that are not more easily and readily detected. In this study, we assessed the extent of microplastics contamination in the sediments, waters, oysters, and selected fishes found in the rivers and coastal areas of Ticalan, Batangas, which were identified from water quality parameters as Class C and CS, respectively. The microplastics were extracted from these samples by chemical digestion of the matrix, series of filtration, and separation by flotation through a density gradient to finally isolate the microplastics which were not dissolved by chemical digestion. The isolated samples were imaged by optical microscopy and characterized based on their descriptive attributes. The results showed the presence of microplastics in all the samples tested, which were found mostly in the form of filaments, fragments, films, and pellets – with most showing weathered, degraded, or angular and irregular surfaces. Identification was done through spectral matching of the Fourier transform infrared spectra of isolated fragments with that of known plastics, although identification in some cases is made uncertain by possibility of degradation of the plastics in the environment. The majority of the isolates showed signature absorption bands of the C-H stretching vibrations of polyethylene-based plastics.


Inhibition Of Hsv-1 Binding By Egcg-Stearate, Valerie Paschalis Jan 2019

Inhibition Of Hsv-1 Binding By Egcg-Stearate, Valerie Paschalis

Theses, Dissertations and Culminating Projects

Herpes simplex virus type 1 (HSV-1) is the causative agent of oral herpes, and is able to establish lifelong latent infection along with painful, recurring symptoms. Epigallocatechin-3- gallate (EGCG) is the most abundant polyphenol derived from green tea (Camellia sinensis), whose anti-inflammatory, antioxidant, anti-cancer, and antiviral properties have been widely studied. Although EGCG is not chemically stable and has poor hydrophobicity, lipophilic derivatives of EGCG have shown increased stability as well as increased antiviral efficacy against HSV. Previous studies have demonstrated that EGCG stearate (EGCG-S), a derivative of EGCG esterified at the 4’ position with stearic acid, is able to …


Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen Jan 2019

Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen

Legacy Theses & Dissertations (2009 - 2024)

It has been known that the template-directed RNA chemical replication reaction produces mixture of backbones containing both 3’-5’ and 2’-5’ linkages. This backbone heterogeneity has been a significant problem in studying the emergence of RNA World from the prebiotic chemistry. However, very recently, it is reported that FMN binding aptamer and a hammerhead ribozyme are still able to retain considerable functions in the presence of certain 2’-5’ linkages, indicating that RNA backbones may be quite flexible and this backbone heterogeneity problem may not be as severe as originally thought. This finding also brings two related important questions: First, how does …


Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy Jan 2019

Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy

Legacy Theses & Dissertations (2009 - 2024)

DksA is a bacterial gene regulator that functions synergistically with the stress alarmone ppGpp to mediate the stringent response. DksA also functions independently of ppGpp to regulate transcription of a number of genes. DksA function is dependent on its binding affinity to RNA polymerase and requires specific interactions between RNAP and catalytic amino acids located on the coiled coil tip, D74 and A76. While much of the previous work on DksA has focused on understanding the mechanisms of action and the numerous gene targets for transcriptional regulation, little is known about the mechanisms by which DksA expression and function may …


Inteins From Pathogenic Microbes As Regulatory Elements And Potential Drug Targets, Cathleen Maria Schiraldi Jan 2019

Inteins From Pathogenic Microbes As Regulatory Elements And Potential Drug Targets, Cathleen Maria Schiraldi

Legacy Theses & Dissertations (2009 - 2024)

Inteins are self-splicing elements that orchestrate the autocatalytic process of protein splicing, during which the intein excises itself from a host polypeptide. This multistep reaction involves a series of coordinated nucleophilic attacks and peptide bond rearrangements that remove the intein and reassemble the flanking halves, called exteins, to form the mature host protein. Some inteins are also mobile elements, and can spread to the same or ectopic sites using an internal homing endonuclease domain.


Evaluation Of Fingerprint Content For Forensic Crime Scene Analysis And Drug Metabolite Detection, Erica Kathryn Brunelle Jan 2019

Evaluation Of Fingerprint Content For Forensic Crime Scene Analysis And Drug Metabolite Detection, Erica Kathryn Brunelle

Legacy Theses & Dissertations (2009 - 2024)

With respect to criminal investigations, one key piece of evidence that often gets overlooked are fingerprints. For years, fingerprint samples have been believed to be useful only for matching purposes using their unique ridges, shapes, and sizes. With the rapid growth of forensic science, it has become evident that the development of fingerprint analysis has been stagnant. The traditional approach has been advantageous for the identification of many individuals; however, many fingerprint samples have been labeled “unusable” due to smudging, smearing, or any one of a myriad of reasons that could cause inconclusive matches. These samples can, however, still be …


Transcriptional Regulation Of Dksa In E. Coli, Daniel Thomas Woods Jan 2019

Transcriptional Regulation Of Dksa In E. Coli, Daniel Thomas Woods

Legacy Theses & Dissertations (2009 - 2024)

DksA is a global transcription factor that binds RNAP directly to regulate the expression of many genes and operons, including ribosomal RNA, in a ppGpp-dependent or ppGpp–independent manner. It is also involved in facilitating the process of DNA replication by removing stalled transcription elongation complexes that could block the progress of the replication fork. In addition, DksA is important for colonization, establishment of biofilms, and pathogenesis. In order to sustain these various functions, an adequate level of cellular DksA is required. This work tested the hypothesis that the E. coli dksA is substantially regulated at the level of transcription. Using …


Sers For Protein Detection At A Single Molecule Level For Developing A New Medical Diagnostics Platform, Lamyaa Almehmadi Jan 2019

Sers For Protein Detection At A Single Molecule Level For Developing A New Medical Diagnostics Platform, Lamyaa Almehmadi

Legacy Theses & Dissertations (2009 - 2024)

A two-step process of protein detection at a single molecule level using Surface Enhanced Raman Spectroscopy (SERS) was developed as a new platform for medical diagnostics in this proof-of-concept study. First, a protein molecule was bound to a linker in the bulk solution and then this adduct was chemically reacted with the SERS substrate. Traut’s Reagent (TR) was used to thiolate Bovine serum albumin (BSA) in solution followed by chemical cross linking to a gold surface through a sulfhydryl group. A Glycine-TR adduct was used as a control sample to identify the protein contribution to the SER spectra. Gold SERS …


Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra Jan 2019

Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra

Legacy Theses & Dissertations (2009 - 2024)

Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. Geranylated-2-thiouridine is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, namely E. coli, E. aerogenes, P. aeruginosa and S. typhimurium by Liu group. It has been found as a post-transcription modification on the wobble position of anticodon of tRNAs specific for glutamic acid, glutamine and lysine. Geranylated-tRNA was shown to correct the frameshifting during the translation of E. coli. However, the reason of the existing of the modification is still largely unclear. To understand why nature incorporates such a hydrophobic group in …


Saliva As A Diagnostic Biological Fluid And The Human Salivary Proteome, Jessica Ghassan Emsies Jan 2019

Saliva As A Diagnostic Biological Fluid And The Human Salivary Proteome, Jessica Ghassan Emsies

Legacy Theses & Dissertations (2009 - 2024)

Saliva is a unique biologic fluid that contains a varying spectrum of proteins, nucleic acids, electrolytes, and hormones.31 It is an exocrine secretion of the salivary glands which is hypotonic in nature with a pH of 7.2-7.4.31 Saliva plays an important role in the oral cavity.33 It lubricates, hydrates, and bathes the oral cavity, therefore, aiding speech and mastication.33 Saliva forms a barrier on the teeth, protects against demineralization, and aids in remineralization.33 Saliva is required for chewing and food bolus preparation, it contains enzymes necessary for digestion, and mediates the sense of taste.33 It also helps wound healing and …


Mechanisms Of Trinucleotide Repeat Instability During Dna Synthesis, Kara Y. Chan Jan 2019

Mechanisms Of Trinucleotide Repeat Instability During Dna Synthesis, Kara Y. Chan

Theses and Dissertations--Toxicology and Cancer Biology

Genomic instability, in the form of gene mutations, insertions/deletions, and gene amplifications, is one of the hallmarks in many types of cancers and other inheritable genetic disorders. Trinucleotide repeat (TNR) disorders, such as Huntington’s disease (HD) and Myotonic dystrophy (DM) can be inherited and repeats may be extended through subsequent generations. However, it is not clear how the CAG repeats expand through generations in HD. Two possible repeat expansion mechanisms include: 1) polymerase mediated repeat extension; 2) persistent TNR hairpin structure formation persisting in the genome resulting in expansion after subsequent cell division. Recent in vitro studies suggested that a …


Discovery And Characterization Of Novel Substrate Selective Inhibitors Of Human Mrp1 (Abcc1), Angelina Sampson Jan 2019

Discovery And Characterization Of Novel Substrate Selective Inhibitors Of Human Mrp1 (Abcc1), Angelina Sampson

Electronic Theses and Dissertations

Multidrug resistance protein 1 (MRP1/ABCC1) actively transports a variety of drugs, toxic molecules and important physiological substrates across the plasma membrane. It can confer broad-spectrum drug resistance and can decrease the bioavailability of many important drugs such as anti-cancer agents, antibiotics, antivirals, antidepressants and antiinflammatory drugs. Calcein-AM, a fluorescent reporter commonly used for studying compound interactions with MRP1 was recently used in the development of a high content imaging-based assay by our group. This assay was robust and had better sensitivity than fluorescent plate readouts. The assay identified 12 MRP1 inhibitors after screening an anticancer library of 386 compounds. Due …


Stabilization Of Dna I-Motif Structures By 7-Aminoactinomycin D, An Anti-Tumor Drug, Justin Lane Parmely Jan 2019

Stabilization Of Dna I-Motif Structures By 7-Aminoactinomycin D, An Anti-Tumor Drug, Justin Lane Parmely

Electronic Theses and Dissertations

Alternative DNA structures are likely to form from Watson-Crick B-form DNA when antitumor drug known to bind DNA loops -- can affect the iM structure. Our results demonstrate as an i-motif (iM). While both structures are known to exist in vivo they are energetically uphill can utilize intercalating cytosine-cytosine base pairing to form a four-stranded structure known controlled by alternative DNA structures like G4s and iMs. especially during processes that involve superhelical duress. A guanosine rich strand can form a facilitate their stabilization. In this report we present data on how 7-aminoactinomycin D -- an formation. Earlier it was believed …


Insights Into Nucleic Acid-Platinum(Ii) Compound Interactions And Structural Impacts, Supuni Duneeshya Kamal Thalalla Gamage Jan 2019

Insights Into Nucleic Acid-Platinum(Ii) Compound Interactions And Structural Impacts, Supuni Duneeshya Kamal Thalalla Gamage

Wayne State University Dissertations

With the discovery of cisplatin in the 1960s, it has been widely studied as a precursor for anticancer drug development. Despite its effectiveness against certain cancers, clinical usage of cisplatin is restricted by a number of side effects and resistance. In the past decade, scientists have been exploring biologically important ligands such as sugar derivatives in the hope of overcoming such challenges. Attachment of a sugar moiety could facilitate lower accumulation of platinum drugs in the body as well as enhance cellular uptake. In this study, a carbohydrate-linked cisplatin analog, cis-dichlorido[(2-β-D-glucopyranosidyl)propane-1,3-diammine]platinum (5) has been studied. The aim was to evaluate …


Functional Characterization Of Accessory Proteins And Novel Activities In Direct And Indirect Trna Aminoacylation, Udumbara Menike Rathnayake Jan 2019

Functional Characterization Of Accessory Proteins And Novel Activities In Direct And Indirect Trna Aminoacylation, Udumbara Menike Rathnayake

Wayne State University Dissertations

Indirect tRNA aminoacylation is essential for most bacteria and archaea, particularly when these species do not have genes encoding asparaginyl- and/or glutaminyl-tRNA synthetase (AsnRS and GlnRS). In the absence of AsnRS, the first step in Asn-tRNAAsn synthesis involves misacylation of tRNAAsn with aspartate to produce Asp-tRNAAsn; this reaction is catalyzed by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS). Subsequently, in bacteria, an amidotransferase called GatCAB converts Asp-tRNAAsn to Asn-tRNAAsn. An analogous, two-step processes exist to produce Gln-tRNAGln. In this case, a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) misacylates tRNAGln to produce Glu-tRNAGln, which is then converted to Gln-tRNAGln by GatCAB. The central hub of …


The Fallacy Of Defensive Protection For Traditional Knowledge, Margo A. Bagley Jan 2019

The Fallacy Of Defensive Protection For Traditional Knowledge, Margo A. Bagley

Faculty Articles

Proponents of databases as defensive protection posit that having sources of traditional knowledge easily accessible to, and searchable by, examiners during the prosecution process should minimize the grant of patents covering traditional knowledge, and avoid the problems such erroneously granted patents may produce. Some countries, such as India, which support an international sui generis positive protection instrument, also support the use of traditional knowledge databases, as the two approaches are not mutually exclusive. India's CSIR, which created and maintains the TKDL, asserts that the database has thwarted the grant of scores of patents in IP offices across the globe, although …


Computational Design And Production Of Levansucrase With Increased Thermostability, Methus Klaewkla Jan 2019

Computational Design And Production Of Levansucrase With Increased Thermostability, Methus Klaewkla

Chulalongkorn University Theses and Dissertations (Chula ETD)

Levansucrase is a carbohydrate-modifying enzyme that catalyzes hydrolysis of sucrose and transfructosylation of a fructosyl unit of sucrose to produce levan and levan-type fructooligosaccharides (LFOs). Due to their various beneficial properties such as low viscosity and non-toxicity. Levan and LFOs have potential applications in many industries such as prebiotics in food industries and anti-tumor agents in pharmaceutical industries. Previous study found that the Y246S mutant of Bacillus licheniformis RN-01 levansucrase (Oligosaccharide Producing Levansucrase, OPL) could effectively produce LFOs, but its thermostability is limited at high temperature. In this study, molecular dynamics (MD) and computational protein design were used to design …


Naturally Derived Compounds As Preventatives Of Proteinopathies, Lois Mendez Jan 2019

Naturally Derived Compounds As Preventatives Of Proteinopathies, Lois Mendez

Open Access Theses & Dissertations

Neurodegenerative diseases, such as Parkinson’s disease (PD), afflict millions worldwide. Of greater concern is the fact that a main risk factor this disease is aging and the baby boomer population is now reaching a geriatric age. Despite the active research in this area, little progress has been made in the development of therapeutic strategies and furthering of our understanding in pinpointing the causal events that onset these disease processes. Our lab has focused on studying the protein homeostasis of key biomarkers in neurodegenerative diseases and examining whether natural compounds can act as neuro-protectants and, thus, attenuate the pathology that ensues …


Benchmark Structures And Harmonic Vibrational Frequencies Of Hydrated Halide Ions: X– (H2o)N, X = F, Cl, Br, And I (Where N = 1 – 4), Caroline Anne Rader Jan 2019

Benchmark Structures And Harmonic Vibrational Frequencies Of Hydrated Halide Ions: X– (H2o)N, X = F, Cl, Br, And I (Where N = 1 – 4), Caroline Anne Rader

Honors Theses

This study extends our efforts to generate benchmark structures and harmonic vi- brational frequencies from neutral hydrogen bonded clusters to solvated ions. The analytical gradients and Hessians developed for the N-body:Many-body integrated QM:QM method facilitate the computation of benchmark-quality properties near the CCSD(T) complete basis set limit. In this work, a series of solvated halide ion sys- tems (X−(H2O)n clusters, where X = F, Cl, Br and I and n = 1 to 4) is being characterized with the MP2 and 2-body:Many-body CCSD(T):MP2 (2b:Mb) meth- ods. For n ≥ 2, the latter technique uses the high-level CCSD(T) method to evaluate …


Amino Acids Profiling For The Diagnosis Of Metabolic Disorders, Yana Sandlers Jan 2019

Amino Acids Profiling For The Diagnosis Of Metabolic Disorders, Yana Sandlers

Chemistry Faculty Publications

Inborn errors of metabolism (IEM) represent a group of inherited diseases in which genetic defect leads to the block on a metabolic pathway, resulting in a single enzyme dysfunction. As a downstream consequence of the residual or full loss of the enzymatic activity, there is an accumulation of toxic metabolites in the proximity of the metabolic block and/or a deficiency of an essential metabolic product which leads to the clinical presentation of the disease. While individually IEMs are rare, a collectively estimated incidence of metabolic inherited disorders is 1:800. The genetic basis of IEMs can involve abnormalities such as point …