Biochemistry, Biophysics, and Structural Biology Commons^™

ผลการปกป้องของสารสกัดใบรางจืดจากการเหนี่ยวนำความเป็นพิษด้วยกลูตาเมตในเซลล์ประสาท Ht-22 ผ่านวิถีออโตฟาจี, วุฒิพงษ์ วงศ์ทิพย์

Chulalongkorn University Theses and Dissertations (Chula ETD)

หนึ่งในสาเหตุสำคัญของการเกิดโรคความเสื่อมของระบบประสาทนั้นเกิดได้จากภาวะเครียดออกซิเดชันภายในเซลล์ประสาท โดยพบว่าสารสื่อประสาทชนิดกลูตาเมตเมื่อมีระดับสูงผิดปกติสามารถเหนี่ยวนำให้เกิดอนุมูลอิสระและภาวะเครียดออกซิเดชันนำไปสู่การสูญเสียและการตายของเซลล์ประสาทได้ โดยเฉพาะการตายของเซลล์จากการเกิดกระบวนการออโตฟาจีมากเกินไป ซึ่งเป็นกระบวนการที่มีบทบาทสำคัญในการควบคุมการตายของเซลล์ผ่านวิถีอื่นๆ รางจืด (Thunbergia laurifolia) เป็นพืชสมุนไพรไทยมีสรรพคุณในการถอนพิษ ต้านการอักเสบ และ ต้านอนุมูลอิสระได้ดี จุดประสงค์ในการวิจัยครั้งนี้ คือ ศึกษาคุณสมบัติการต้านอนุมูลอิสระของสารสกัดหยาบจากใบรางจืด และการปกป้องการตายของเซลล์ประสาทผ่านวิถีออโตฟาจี จากการเหนี่ยวนำภาวะเครียดออกซิเดชันด้วยกลูตาเมตโดยทดสอบในเซลล์ประสาทส่วนฮิปโปแคมปัสของหนูชนิด HT-22 ใบรางจืดถูกนำมาสกัดด้วยเอทานอล จากผลการทดสอบพบว่าสารสกัดหยาบจากใบรางจืดมีความสามารถในการต้านอนุมูลอิสระ และมีปริมาณสารประกอบ ฟลาโวนอยด์และฟีนอลิกสูง โดยจากการวิเคราะห์ด้วยเครื่อง LC-MS และเปรียบเทียบผลที่ได้กับฐานข้อมูล METLIN-(CA, USA) พบสารออกฤทธิ์สำคัญที่ยังไม่มีรายงานในสารสกัดเอทานอลของใบรางจืด ได้แก่ Apigenin 7-O-glucoside และ 7-Hydroxycoumarin ยิ่งไปกว่านั้นสารสกัดหยาบจากใบรางจืดยังสามารถลดการตายของเซลล์ประสาทจากการเหนี่ยวนำความเป็นพิษด้วยกลูตาเมต โดยสามารถยับยั้งการเกิดอนุมูลอิสระภายในเซลล์ และเพิ่มการแสดงออกของยีนต้านอนุมูลอิสระที่ทำหน้าที่สำคัญในกระบวนการต้านอนุมูลอิสระในร่างกาย ได้แก่ superoxide dismutase 1 และ 2 (SOD1 and SOD2) catalase (CAT) และ glutathione peroxidase (GPx) ซึ่งสัมพันธ์กับการลดการเกิดกระบวนการออโตฟาจีภายในเซลล์และเพิ่มปริมาณ ไมโตคอนเดรียโปรตีน โดยพบว่าสารสกัดหยาบจากใบรางจืดสามารถลดอัตราส่วนการแสดงออกของโปรตีน LC3B-II/LC3B-I และเพิ่มการแสดงออกของไมโตคอนเดรียโปรตีน TOM20 เมื่อทำการตรวจหาตำแหน่งที่จำเพาะต่อการแสดงออกของโปรตีนในกระบวนการออโตฟาจี (LC3B) และไมโตคอนเดรียด้วยกล้องจุลทรรศน์ชนิดคอนโฟคอล พบว่า สารสกัดหยาบจากใบรางจืดสามารถลดการเกิด LC3-puncta ซึ่งเป็นลักษณะเด่นของการเกิดกระบวนการออโตฟาจี นอกจากนี้สารสกัดหยาบจากใบรางจืดยังลดการ colocalization ของ LC3B และไมโตคอนเดรีย จากผลการศึกษานี้เราพบสารออกฤทธิ์สำคัญใหม่ที่ยังไม่มีรายงานมาก่อนของใบรางจืด โดยสารออกฤทธิ์นี้มีความสามารถในการปกป้องเซลล์ประสาทชนิด HT-22 จากภาวะเครียดออกซิเดชันและเป็นปัจจัยสำคัญทำให้สารสกัดจากใบรางจืดมีความสามารถลดการตายของเซลล์ประสาทผ่านวิถีออโตฟาจีได้ ซึ่งอาจสามารถนำไปพัฒนาเป็นสมุนไพรทางเลือกหรือยาเพื่อใช้ในการป้องกันหรือรักษาการเกิดโรคความเสื่อมของระบบประสาทได้ในอนาคต

Knob-Socket Investigation Of Stability And Specificity In Alpha-Helical Secondary And Quaternary Packing Structure, Taylor Renee Rabara

University of the Pacific Theses and Dissertations

The novel knob-socket (KS) model provides a construct to interpret and analyze the direct contributions of amino acid residues to the stability in α-helical protein structures. Based on residue preferences derived from a set of protein structures, the KS construct characterizes intra- and inter-helical packing into regular patterns of simple motifs. The KS model was used in the de novo design of an α-helical homodimer, KSα1.1. Using site-directed mutagenesis, KSα1.1 point mutants were designed to selectively increase and decrease stability by relating KS propensities with changes to α-helical structure. This study suggests that the sockets from the KS Model can …

Functional Analysis Of Bacillus Anthracis Aspartate Transcarbamoylase And Dihydroorotase, Katelyn Leigh Schwager Silva

Wayne State University Theses

There are many enzymes required for efficient and proper pyrimidine biosynthesis. The two that are most important and were discussed in this thesis are aspartate transcarbamoylase (ATCase) and dihydroorotase (DHOase). Both play an important role in not only pyrimidine biosynthesis production, but also mechanistic regulation of de novo synthesis. Anthrax is an infection caused by Bacillus anthracis. Here we studied ATCase and DHOase in Bacillus Anthracis. In this thesis we understood the effects of the enzymes ATCase and DHOase on pyrimidine biosynthesis. Adequate inhibitors of these enzymes would result in cell death and could pose as a cure to infection …

Cyclophilin A As A Molecular Switch Regulating Prolactin Receptor Mediated Signaling, Mammary Tumorigenesis And Metastasis, Shawn Hakim

Theses and Dissertations

Prolactin (PRL) and its receptor (PRLr) have been implicated in the development and progression of human breast cancer. PRL activates its receptor and induces activation of proximal Janus kinase 2 (Jak2) for signal transduction. Here, we sought to determine the role of PRLr-associated peptidyl-prolyl isomerase, cyclophilin A (CypA), in modulating structure/function relationships of the PRLr. It was demonstrated that CypA mediated PRL-induced conformational change of the CFP- and -YFP tagged forms of the PRLr cytoplasmic-tail, whereas CypA inhibition by NIM811 (N-methyl-4-isoleucine cyclosporin) or knockdown blocked the conformational change of the PRLr assessed by Fluorescence Resonance Energy Transfer (FRET) signal or …

Electrostatic Networks And Mechanisms Of Δph-Dependent Gating In The Human Voltage-Gated Proton Channel Hv1, Ashley L. Bennett

Theses and Dissertations

The structure of the voltage-gated proton (H⁺) channel Hv1 is homologous to the voltage sensor domain (VSD) of tetrameric voltage-gated Na⁺, K⁺ and Ca²⁺ channels (VGCs), but lacks a pore domain and instead forms a homodimer. Similar to other VSD proteins, Hv1 is gated by changes in membrane potential (V), but unlike VGCs, voltage-dependent gating in Hv1 is modulated by changes in the transmembrane pH gradient (DpH = pH_o - pH_i). In Hv1, pH_o or pH_i changes shift the open probability (P_OPEN)-V relation by ~40 mV per …

Targeting Sphingosine Kinase 2 As A Treatment For Cholangiocarcinoma, Anthony D. Stillman

Theses and Dissertations

Cholangiocarcinoma (CCA) has a high mortality rate and its occurrence is rising. This increase prompts the need for improved CCA treatments. Studies have suggested that CCA is highly reliant on the sphingosine-1-phosphate-receptor-2 (S1PR2) and sphingosine kinase 2 (SphK2). Recently, a competitive SphK2 inhibitor, ABC294640, has been approved for clinical trial. ABC294640 has the potential to treat CCA, which is support by a phase I clinical study that was able to temporarily treat a patient suffering from metastasized CCA with ABC294640. To determine the viability of ABC294640 as a treatment for CCA, this study focused on determining the effects of ABC294640 …

Stat5b And Stat5 Tetramers Are Essential For Ige-Mediated Mast Cell Function, Kasalina N. Kiwanuka

Theses and Dissertations

Signal Transducers and Activators of Transcription (STATs) are latent transcription factors that mediate several cellular responses. This protein family consists of seven members, STAT1 – 6 including two closely related molecules, STAT5a and STAT5b, that show 96% amino acid sequence homology and are critical for lymphoid, myeloid and erythroid cell development and function. Activated STAT proteins dimerize and translocate to the nucleus, where they bind to high-affinity DNA motifs to modulate gene expression. We recently identified STAT5b as the critical regulator of IgE-mediated cytokine production in mast cells. STAT5b knockout (KO) cells show decreased sensitivity to IgE-mediated passive systemic anaphylaxis …

Near-Infrared Fluorescent Probes For Sensitive Determination Of Lysosomal & Mitochondrial Ph In Live Cells, Wafa Mazi

Dissertations, Master's Theses and Master's Reports

Varied intracellular pH levels are critical for various physiological processes such as enzymatic activity, cell proliferation and apoptosis, ion transport, and muscle contraction. Cellular compartments, like lysosomes, must retain an acidic environment (pH ~ 4.5) to activate hydrolytic enzymes necessary for the breakdown of large biomolecules. Another cellular organelle, the mitochondria, provides the cell with energy and must retain an alkalis environment (pH ~ 8.0) for proper function. Substantial lysosomal and mitochondrial pH deviation is associated with cellular dysfunction and disease. Therefore, the precise detection of lysosomal and mitochondrial pH is essential to provide a better understanding of cellular physiological …

Characterization Of The Microbial Phosphonate-Activating Pntc Enzymes, Kyle Rice

Theses and Dissertations (Comprehensive)

New strategies are urgently needed to combat infectious diseases in an era of rising antibiotic resistance. Furthermore, an emerging appreciation for the human microbiome’s role in maintaining health motivates discovery of species-specific antibiotics that minimally disrupt our native bacterial communities. Small molecule modifications to bacterial cell surfaces represent a potentially rich source of new targets for next generation antibiotics, as these molecules mediate virulence and evasion of the host immune response. Phosphocholine (PCho) is a rare cell surface modification that contributes to virulence, and modifications with phosphonates like 2-aminoethylphosphonate (AEP) are even more unusual and therefore provide opportunities for species- …

Investigating Potential Multi-Protein Complexes Involving Emx2, Nicole Enger

All Master's Theses

The neocortex of the mammalian brain is allocated into specialized areas during embryonic development. In mice, as well as humans, the neocortex develops four primary areas: somatosensory, auditory, visual, and motor. In the adult neocortex, the boundaries between these four areas are marked by differences in cellular architecture and gene expression patterns. However, these physical boundaries are not evident during embryonic development of this structure. Rather, the neocortex initially appears uniform across its expanse, with one exception: a handful of proteins that regulate neocortical arealization are generated in gradients across the expanse of the neocortex and control the size of …

Immunomagnetic Beads Coupled With Anti-Ph-20 Antibodies To Isolate Sperm From Dna Mixtures For Sexual Assault Kit Application, Kayla Becks

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sexual Assault Kits (SAKs) account for a large portion of DNA mixture samples that are processed within a forensic laboratory, most commonly in the form of vaginal swabs. A typical vaginal swab from a SAK contains the female victim's epithelial cells and varying concentrations of sperm cells left by the perpetrator. The key to analyzing these types of samples is to separate the mixture into male and female fractions. As such, there is a demand to develop novel techniques that have the capability of recovering as much of the male fraction as possible, specifically in cases where there is a …

Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background: Group A Streptococcus (GAS) is responsible more than 700 million infections worldwide each year. Most of these infections start with initial colonization of the throat and skin, which is augmented by surface adhesins. The streptococcal collagen-like protein 1 (Scl1) is a major adhesin expressed by GAS that contains an N-terminal sequence-variable (V) domain, protruded away from the cell surface by the collagen domain. The Scl-V domain is comprised of three pairs of anti-parallel α-helices interconnected by surface-exposed loops. For attachment, GAS adhesins require a portal of entry, such as a wound or breach in the epithelium, to enter …

Regulator Of G Protein Signaling-12 (Rgs12) In Dopaminergic And Kappa Opioid Receptor-Dependent Signaling And Behavior, Joshua David Gross

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dopaminergic neurotransmission is critically involved in the etiology and treatment of many psychiatric and neurological disorders. One modulator of dopaminergic neurotransmission is the kappa opioid receptor (KOR) -- a G protein-coupled receptor (GPCR) that is densely expressed within dopaminergic neurons and circuits. GPCRs are tightly regulated by a variety of intracellular signaling molecules, including Regulator of G Protein Signaling (RGS) proteins. Canonically, RGS proteins act as GTPase accelerating proteins (GAPs) on GTP-bound Ga subunits following GPCR activation, thereby hastening the rate at which GPCR-mediated G protein signaling is terminated. However, some RGS proteins exhibit more complex mechanisms of action on …

In Silico Development Of An Rna Aptamer Library To Be Use For The Selection Of Rna Aptamer That Target Biomolecules, Nehad Nawfawi

Electronic Theses & Dissertations

The systematic evolution of ligands by exponential enrichment (SELEX) is a powerful method for the development of high affinity RNA ligands toward and infinite array of target molecules. SELEX is based upon the generation of a randomized population of RNA or DNA molecules followed by a target molecule that selects high affinity ligands from the randomized population followed by the subsequent amplification of the selected molecules. The procedure of selection and amplification is typically carried out through multiple cycles to insure that the identified ligands exhibits the highest affinity toward the target. The procedure is very time- consuming often taking …

Methanogens: Pushing The Boundaries Of Biology, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Methanogens are anaerobic archaea that grow by producing methane gas. These microbes and their exotic metabolism have inspired decades of microbial physiology research that continues to push the boundary of what we know about how microbes conserve energy to grow. The study of methanogens has helped to elucidate the thermodynamic and bioenergetics basis of life, contributed our understanding of evolution and biodiversity, and has garnered an appreciation for the societal utility of studying trophic interactions between environmental microbes, as methanogens are important in microbial conversion of biogenic carbon into methane, a high-energy fuel. This review discusses the theoretical basis for …

Methanogens: Pushing The Boundaries Of Biology, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Methanogens are anaerobic archaea that grow by producing methane gas. These microbes and their exotic metabolism have inspired decades of microbial physiology research that continues to push the boundary of what we know about how microbes conserve energy to grow. The study of methanogens has helped to elucidate the thermodynamic and bioenergetics basis of life, contributed our understanding of evolution and biodiversity, and has garnered an appreciation for the societal utility of studying trophic interactions between environmental microbes, as methanogens are important in microbial conversion of biogenic carbon into methane, a high-energy fuel. This review discusses the theoretical basis for …

The Drug Discovery Of Potential Anti-Cancer Agents To Inhibit The Demethylation Catalytic Activity Of The Jmjc Domain Of Kdm3a, Balgees Alshanqeti

Electronic Theses & Dissertations

Lysine demethylase 3A (KDM3A) is an enzyme that specifically catalyzes the removal of 2 or three methyl groups from lysine 9 of histone 3 (KH3). It belongs to the family of histone demethylases that contain the Jumonji C (JmjC) domain, which means cruciform in Japanese. KDM3A also belongs to a family of hydroxylases that are alpha-ketoglutarate dependent. The role of KDM3A in the cell is not yet understood, however, and based on its demethylation of studies have showed that its expression is elevated in embryonic stem cells in humans and in mice. In general, patterns of elevated expression of KDM3A …

Functional And Mechanical Role Of Splice Variant Of Mucin4 (Muc4/X) And Trefoil Factors In Pancreatic Cancer Pathogenesis, Rahat Jahan

Theses & Dissertations

Pancreatic Cancer (PC) is one of the vicious cancers as it ranks third in the race of leading cause of cancer-related death. Lack of early diagnostic marker, poor understanding of molecular mechanism of the disease and failure to conventional chemotherapy makes this disease dreadful.

Mucin 4 (MUC4), a high molecular weight glycoprotein is one of the top differentially expressed molecules in PC while not expressed in normal pancreas. Accumulating evidence from our lab suggested its tumorigenic role in PC by increasing cell proliferation, invasion, chemotherapy resistance, tumor growth, and metastasis. Previously, our lab and other has identified 24 different splice …

Expression Analysis Of Micrornas And Microrna-Like Rnas In Aspergillus Flavus-Infected Aflatoxin Resistant And Susceptible Maize Inbred Lines, Amanda Benton Harper

Theses and Dissertations

Corn (Zea mays) is frequently infected by a soil fungal pathogen Aspergillus flavus. The fungus produces aflatoxins, which cause liver cancer. Maize inbred lines that are resistant to infection by A. flavus have been developed, and these inbred lines provide excellent models for studying molecular mechanisms of maize resistance to the fungus. MicroRNA-like RNAs (milRNAs) recently identified in A. flavus had been found to be correlated with aflatoxin production conditions, suggesting that the milRNAs might play a role in the regulation of aflatoxin production. In this research, small RNAs were isolated from kernels of maize (resistant Mp719 and susceptible Va35) …

Carbene Triel Bonds Between Trr3 (Tr=B, Al) And N-Heterocyclic Carbenes, Zongqing Chi, Wenbo Dong, Qingzhong Li, Xin Yang, Steve Scheiner, Shufeng Liu

Chemistry and Biochemistry Faculty Publications

The carbene triel bond is predicted and characterized by theoretical calculations. The C lone pair of N‐heterocyclic carbenes (NHCs) is allowed to interact with the central triel atom of TrR₃ (Tr = B and Al; R = H, F, Cl, and Br). The ensuing bond is very strong, with an interaction energy of nearly 90 kcal/mol. Replacement of the C lone pair by that of either N or Si weakens the binding. The bond is strengthened by electron‐withdrawing substituents on the triel atom, and the reverse occurs with substitution on the NHC. However, these effects do not strictly follow …

Chemical Analysis Of Aerosol Particle Surfaces, Hillary Woolf

Fall Student Research Symposium 2018

Aerosol particles are thought to impact climate properties. The ability to probe aerosols to understand their chemical properties has been difficult due to a lack of appropriate analytical techniques. Here we present interface-specific SHS techniques to allow for in situ analysis of aerosol particles. Transportation of aerosols from their collection site to the laboratory disturbs their chemical and physical properties thus making it difficult to take accurate measurements of aerosol particles. We show that using a CCD detector is a more effective option for producing more sensitive results and can greatly reduce sampling time and could possibly detect measurements from …

Carbohydrate Extraction From The Chorella Vulgaris Microalgae Strain, William Hammann, Wayne Seames, Andrew Ross

Essential Studies UNDergraduate Showcase

The cultivation and exploitation of microalgae biomass as a source of renewable fuels and other chemicals has been an active area of research due to microalgae’s high productivity and the relatively high concentrations of valuable intracellular components, like lipids (fatty acid-based oils), proteins, and polysaccharides. Commercialization of this technology will help mitigate global climate change by reducing fossil-derived products by producing analog renewable fuels and chemicals. Traditionally, the main focus of microalgae-based fuels/chemicals research and development has been on the lipids that many strains generate, but current research shows that solely recovering the oils may not be cost competitive with …

Structural Characterization Of Feruloylated Arabinoxylan Oligosaccharides Isolated From Rice Bran Fiber, Kan Takahashi

Student Theses and Dissertations

Increased consumption of soluble cereal arabinoxylan (AX), and feruloylated arabinoxylan oligosaccharides (FAXOs) generated from it, may promote healthful gastro-intestinal functioning through modulating the gut microbiota and tuning innate immune response function at the gut epithelium. FAXO compositions isolated from rice bran fiber were characterized for their oligosaccharide mass profiles (MALDI-TOF MS) and monosaccharide compositions (GC-FID). Results indicated gluco-oligosaccharides were covalently associated with the FAXOs. I tested the hypothesis that the association represents a novel intermolecular crosslink between mixed linkage β-glucan and AX in rice caryopsis cell walls. The structural characteristics of gluco-oligosaccharides were analyzed to determine glycosidic linkages (GC-MS) and …

Distribution Of Dengue And Zika Virus Igg Immunoglobulin, Madison Smith, Awadalkareem Adam, Anuja Mathew

Senior Honors Projects

Introduction. Dengue Virus (DENV) and Zika Virus (ZIKV) are viruses that belong to the Flavivirus family. They are transmitted by the Aedes aegypti species of mosquitoes. Infection with DENV can result in no symptoms, mild symptoms which include fever, rash, and headache (dengue fever) or more severe symptoms which include hemorrhage, dengue hemorrhagic fever (DHF) and shock, dengue shock syndrome (DSS). ZIKV, until recently caused mild disease but an outbreak in Brazil was associated with fetal complications such as microcephaly or Guillain-Barré syndrome in adults. Due to the similarity between ZIKV and DENV, antibodies (Abs) generated in humans to these …

Generating High-Order Optical And Spin Harmonics From Ferromagnetic Monolayers, G.P. Zhang, M.S. Si, M. Murakami, Y.H. Bai, Thomas George

Chemistry & Biochemistry Faculty Works

High-order harmonic generation (HHG) in solids has entered a new phase of intensive research, with envisioned band-structure mapping on an ultrashort time scale. This partly benefits from a flurry of new HHG materials discovered, but so far has missed an important group. HHG in magnetic materials should have profound impact on future magnetic storage technology advances. Here we introduce and demonstrate HHG in ferromagnetic monolayers. We find that HHG carries spin information and sensitively depends on the relativistic spin–orbit coupling; and if they are dispersed into the crystal momentum k space, harmonics originating from real transitions can be k-resolved and …

Brca1 And Brca2 5′ Noncoding Region Variants Identified In Breast Cancer Patients Alter Promoter Activity And Protein Binding, Leslie J. Burke, Jan Sevcik, Gaetana Gambino, Emma Tudini, Eliseos J. Mucaki, Ben C. Shirley, Phillip Whiley, Michael T. Parsons, Kim De Leeneer, Sara Gutiérrez-Enríquez, Marta Santamariña, Sandrine M. Caputo, Elizabeth Santana Dos Santos, Jana Soukupova, Marketa Janatova, Petra Zemankova, Klara Lhotova, Lenka Stolarova, Mariana Borecka, Alejandro Moles-Fernández, Siranoush Manoukian, Bernardo Bonanni, Stacey L. Edwards, Marinus J. Blok, Thomas Van Overeem Hansen, Maria Rossing, Orland Diez, Ana Vega, Kathleen B.M. Claes, David E. Goldgar, Etienne Rouleau

Biochemistry Publications

© 2018 The Authors. Human Mutation published by Wiley Periodicals, Inc. The widespread use of next generation sequencing for clinical testing is detecting an escalating number of variants in noncoding regions of the genome. The clinical significance of the majority of these variants is currently unknown, which presents a significant clinical challenge. We have screened over 6,000 early-onset and/or familial breast cancer (BC) cases collected by the ENIGMA consortium for sequence variants in the 5′ noncoding regions of BC susceptibility genes BRCA1 and BRCA2, and identified 141 rare variants with global minor allele frequency < 0.01, 76 of which have not been reported previously. Bioinformatic analysis identified a set of 21 variants most likely to impact transcriptional regulation, and luciferase reporter assays detected altered promoter activity for four of these variants. Electrophoretic mobility shift assays demonstrated that three of these altered the binding of proteins to the respective BRCA1 or BRCA2 promoter regions, including NFYA binding to BRCA1:c.-287C>T and PAX5 binding to BRCA2:c.-296C …

Functional Consequence Of Psat1 Association On Pkm2'S Inherent Enzymatic Activity., Alexis Avidan Vega

Electronic Theses and Dissertations

Pyruvate kinase M2 (PKM2) is predominantly found in tumors, where it allows the cancer cell to adapt to metabolic conditions through allosteric regulation of its activity. We recently discovered that phosphoserine aminotransferase 1 (PSAT1) associates with and activates PKM2. Here, I sought to affirm PSAT1's ability to increase PKM2 activity through kinetic and association studies of wild-type or mutant PKM2 enzymes. I demonstrate that His-tagged WT and mutant PKM2 enzymes are active, exhibit different kinetics, yet cannot be activated by PSAT1. Comparison studies using untagged WT PKM2 suggest that inclusion of the His-tag disrupts PSAT1 association. In support, pull-down strategies …

Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey

Electronic Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacillus able to colonize a wide variety of environments. In the human host, P. aeruginosa can establish an acute infection or persist and create a chronic infection. P. aeruginosa is able to establish a niche and persist in human hosts by using a wide array of virulence factors used for: movement, killing host cells, and evading immune cells and antibiotics. Understanding virulence factors and their regulation has proved to be an important means of combating the morbidity and mortality of P. aeruginosa as well as the ever-increasing threat of drug resistance. By targeting virulence factors …

The First In Vivo Human Methionine Sulfide Proteome And The Impact Of Smoking, Abdullah Qassab

Graduate Theses and Dissertations

Reactive oxygen species are naturally generated within the human body and they are known to modulate signaling pathway and mediate other physiological activities. However, excessive generation of ROS and the inability of body defense system in detoxifying them results in the so called “oxidative stress”. Methionine has powerful antioxidant properties due to the presence of electronegative sulfur in its structure. Therefore, Met is readily oxidized, and methionine sulfoxide has been linked to several pathological conditions.

The urinary proteome is an attractive candidate for the discovery of biomarkers to diagnose and classify health conditions because of the non-invasive collection procedure. However, …

Investigation Of Electrolytic Flocculation For Microalga Scenedesmus Sp Using Aluminum And Graphite Electrodes, Shihong Liu, Husam A. Abu Hajar, Guy Riefler, Ben J. Stuart

Civil & Environmental Engineering Faculty Publications

Electrolytic flocculation using non-sacrificial electrodes with flocculants added was studied on harvesting Scenedesmus sp. In order to optimize the operating conditions of the electrolytic flocculation process and to quantify the amount of flocculants added, aluminum electrodes were first used in the process. It was found that under optimal conditions, the microalgae removal efficiency using aluminum electrodes could reach 98.5%, while 34.2 mg L^-1 of aluminum ions were released during the process. Different metal electrodes were also studied, but high microalgae removal efficiency was witnessed only using aluminum electrodes, indicating the influence of the aluminum ion in flocculation. When non-sacrificial …