Biochemistry Commons^™

Determination And Dissection Of Dna-Binding Specificity For The Thermus Thermophilus Hb8 Transcriptional Regulator Tthb099, Kristi Moncja

Master of Science in Chemical Sciences Theses

Transcription factors (TFs) have been extensively researched in certain well-studied organisms but far less so in others. Following the whole-genome sequencing of a new organism, TFs are typically identified through their homology with related proteins in other organisms. However, recent findings demonstrate that structurally similar TFs from distantly related bacteria are not usually evolutionary orthologs. Here we explore TTHB099, a cAMP receptor protein (CRP)-family TF from the extremophile Thermus thermophilus HB8. Using the in vitro iterative selection method Restriction Endonuclease Protection, Selection and Amplification (REPSA), we identified the preferred DNA-binding motif for TTHB099, 5'-TGT(A/g)n(t/c)c(t/c)(a/g)g(a/g)n(T/c)ACA-3', and mapped potential binding sites, and …

Deciphering The Catalytic Mechanism Of Human Manganese Superoxide Dismutase, Jahaun Azadmanesh

Theses & Dissertations

The livelihood of human cells is heavily dependent on the ability to modulate the presence of highly reactive oxygen-based molecules termed reactive oxygen species (ROS). In excess, ROS facilitate oxidative damage to the macromolecules of cellular life. SODs are the major family of antioxidant proteins that prevent the buildup of overwhelming amounts of ROS within cells. Sometimes dubbed the “first line of defense” against oxidative damage, SODs defend against the harmful accumulation of ROS by eliminating superoxide. Superoxide is a ROS itself that is also a precursor to much more harmful ROS molecules. MnSOD is the manganese containing form of …

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …

Elucidating The Role Of Ecdysoneless In Mrna Processing, Irfana Saleem

Theses & Dissertations

The mammalian orthologue of the evolutionarily conserved Ecdysoneless (ECD) protein is required for embryogenesis, cell cycle progression and mitigation of ER stress. However, the molecular mechanisms of ECD function in mammalian cells remain unclear. Here, using mass spectrometry analysis of the mammalian ECD interactome, we identified several components of the mRNA export complexes as binding partners of ECD and then characterized the functional interaction of ECD with key mRNA export-related DEAD BOX protein helicase DDX39A and its associated partners. FISH analysis of Poly-A-tailed mRNAs revealed that ECD depletion/deletion blocks the mRNA export from the nucleus to the cytoplasm. We have …

Single-Fluorophore Sensors For Mechanical Force In Living Cells, Sarah Kricheff

Honors Scholar Theses

Mechanotransduction is the process by which a mechanical stimulus is converted to a cellular signal. This process is heavily influential of cell morphology, differentiation, and behavior. However, altered levels of mechanical stimuli are also found in many pathological contexts. For example, cancerous cells have stiffer surrounding tissue than healthy cells, and research suggests that this alters cell behavior and promotes metastasis. Despite these findings, the cellular processes behind these signaling alterations remain widely unknown. Understanding these cascades is critical, as involved proteins can give us a deeper understanding of the role of mechanotransduction, and certain proteins can potentially be targeted …

Dissecting Regulation Mechanism Of Interdomain Electron Transfer In Nitric Oxide Synthases, Huayu Zheng

Chemistry and Chemical Biology ETDs

Nitric oxide (NO) is generated by one of the three isoforms of mammalian NO synthases (NOSs), neuronal, endothelial and inducible NOS (nNOS, eNOS, and iNOS, respectively). Dysregulated NOS is implicated in pathologies of numerous severe diseases including Alzheimer and Parkinson’s diseases. Molecular mechanisms of NOS regulation, once fully understood, are potentially key targets for development of selective new pharmaceuticals for treating these diseases that currently lack effective treatments.

Despite recent developments, there are significant gaps in current understanding of the regulation mechanism of the FMN-heme interdomain electron transfer (IET), an essential step in NOS, by its key regulators such as …

Impact Of Cd82 Expression On Acute Myeloid Leukemia Chemosensitivity And Quiescence, Muskan Floren

Biomedical Sciences ETDs

Acute Myeloid Leukemia (AML) patients respond favorably to induction chemotherapy, however, long-term outcomes remain poor due to a high rate of chemoresistance and bone marrow minimal residual disease. To improve long-term patient outcomes, it’s critical to identify regulators of chemotherapy resistance in AML and develop therapies that are directed towards bone marrow resident AML cells. In Chapter 2, we uncover the impact of CD82 expression in AML response to chemotherapeutic treatment and the contribution of Protein Kinase C α (PKCα) and β1 integrin signaling in promoting p38 MAPK activation to support CD82-mediated AML cell survival. In Chapter 3, we …

Pathway‐Extended Gene Expression Signatures Integrate Novel Biomarkers That Improve Predictions Of Patient Responses To Kinase Inhibitors, Ashis Bagchee‐Clark, Eliseos J. Mucaki, Tyson Whitehead, Peter Rogan

Biochemistry Publications

Cancer chemotherapy responses have been related to multiple pharmacogenetic biomarkers, often for the same drug. This study utilizes machine learning to derive multi‐gene expression signatures that predict individual patient responses to specific tyrosine kinase inhibitors, including erlotinib, gefitinib, sorafenib, sunitinib, lapatinib and imatinib. Support vector machine (SVM) learning was used to train mathematical models that distinguished sensitivity from resistance to these drugs using a novel systems biology‐based approach. This began with expression of genes previously implicated in specific drug responses, then expanded to evaluate genes whose products were related through biochemical pathways and interactions. Optimal pathway‐extended SVMs predicted responses in …

Sestrins: Emerging Dynamic Stress-Sensors In Metabolic And Environmental Health, Seung Hyun Ro, Julianne Fay, Cesar I. Cyuzuzo, Yura Jang, Naeun Lee, Hyun Seob Song, Edward N. Harris

Department of Biochemistry: Faculty Publications

Proper timely management of various external and internal stresses is critical for metabolic and redox homeostasis in mammals. In particular, dysregulation of mechanistic target of rapamycin complex (mTORC) triggered from metabolic stress and accumulation of reactive oxygen species (ROS) generated from environmental and genotoxic stress are well-known culprits leading to chronic metabolic disease conditions in humans. Sestrins are one of the metabolic and environmental stress-responsive groups of proteins, which solely have the ability to regulate both mTORC activity and ROS levels in cells, tissues and organs. While Sestrins are originally reported as one of several p53 target genes, recent studies …

Fluorescence Spectroscopic And Molecular Modelling Studies On The Molecular Interaction Mechanism Of Bromodeoxyuridine With Human Serum Albumin, Amira Adlin Roslan

Student Works (2020-2029)

The interaction of a nucleoside analogue, bromodeoxyuridine (BrdU) with human serum albumin (HSA) was studied to investigate the binding phenomenon and analyze the protein conformation upon BrdU binding. Multiple spectroscopic techniques, viz. intrinsic and three-dimensional (3-D) fluorescence, ultraviolet-visible (UV-Vis) absorption and circular dichroism (CD) spectroscopy along with molecular docking were used. A decrease in the Stern-Volmer constant (Ksv) with the increase in temperature suggested BrdU-induced quenching of protein fluorescence as static quenching and thus implied BrdU−HSA complex formation. This was also supported by UV-Vis absorption spectral results, showing hyperchromism in the absorption spectrum of HSA upon BrdU addition. Intermediate binding …

The Circadian Clock—A Molecular Tool For Survival In Cyanobacteria, Pyonghwa Kim, Manpreet Kaur, Hye-In Jang, Yongick Kim

Chemistry Faculty Research

Cyanobacteria are photosynthetic organisms that are known to be responsible for oxygenating Earth’s early atmosphere. Having evolved to ensure optimal survival in the periodic light/dark cycle on this planet, their genetic codes are packed with various tools, including a sophisticated biological timekeeping system. Among the cyanobacteria is Synechococcus elongatus PCC 7942, the simplest clock-harboring organism with a powerful genetic tool that enabled the identification of its intricate timekeeping mechanism. The three central oscillator proteins—KaiA, KaiB, and KaiC—drive the 24 h cyclic gene expression rhythm of cyanobacteria, and the “ticking” of the oscillator can be reconstituted inside a test tube just …

Unconventional Constituents And Shared Molecular Architecture Of The Melanized Cell Wall Of C. Neoformans And Spore Wall Of S. Cerevisiae, Christine Chrissian, Coney Pei-Chin Lin, Emma Camacho, Arturo Casadevall, Aaron M. Neiman, Ruth E. Stark

Publications and Research

The fungal cell wall serves as the interface between the cell and the environment. Fungal cell walls are composed largely of polysaccharides, primarily glucans and chitin, though in many fungi stress-resistant cell types elaborate additional cell wall structures. Here, we use solid-state nuclear magnetic resonance spectroscopy to compare the architecture of cell wall fractions isolated from Saccharomyces cerevisiae spores and Cryptococcus neoformans melanized cells. The specialized cell walls of these two divergent fungi are highly similar in composition. Both use chitosan, the deacetylated derivative of chitin, as a scaffold on which a polyaromatic polymer, dityrosine and melanin, respectively, is assembled. …

Implications Of Lysine Acetylation On The Enzymes Of The Tca Cycle, Sumana Venkat

Graduate Theses and Dissertations

The tricarboxylic acid (TCA) cycle is a central route for the energy production via oxidative phosphorylation and is ubiquitous throughout nature. Apart from playing a major role in energy provision, it is also essential for a wide range of physiological functions in any organism. Although an increasing emphasis is laid on the interlinking role of the cycle, its regulation and control are less very less understood. As the field progresses, the consequences of TCA cycle anomalies are shown to be tied to various cancers and other disorders. The matter becomes more complex when considering the varying functions of the isozymes …

Design Of Hfgf1 Variant(S) With Increased Stability And Enhanced Bioactivity, Shilpi P. Agrawal

Graduate Theses and Dissertations

Fibroblast growth factors (FGFs) are involved in various cellular processes such as cell growth,proliferation, differentiation, migration, angiogenesis, wound healing and embryonic development. Human acidic fibroblast growth factor (hFGF1) binds non-selectively to all the four FGF-receptors and is therefore considered as a powerful mitogen with broadest specificity. However, pharmacological applications of hFGF1 are restricted due to the low thermal stability of the growth factor. hFGF1 has low thermodynamic stability under physiological temperatures which leads to impairment of cellular signaling process thereby preventing its potential mitogenic properties. hFGF1 has a heparin binding pocket at the C-terminus which comprises of positively charges residues. …

Investigating The Disorder And Compaction Of Designed Minielastin Using Nuclear Magnetic Resonance., Ma Faye Charmagne Aquino Carvajal

Electronic Theses and Dissertations

Minielastins are elastin-based proteins with alternating hydrophobic and cross-link modules similar to tropoelastin. Tropoelastin is the ~70 kDa soluble monomeric precursor of elastin. The extracellular matrix protein, elastin provides elasticity to tissues and organs such as lungs, arteries and ligaments. The elastic properties of natural elastin are believed to be entropic in origin. In vivo, the elastin matrix is approximately 50% water by weight. Without water, elastin is brittle and hard. Minielastins, like tropoelastin, undergo a liquid-liquid phase transition upon an increase in temperature. Factors such as hydrophobicity, chain length and concentration affect the coacervation temperature, T_c. The …

Predictors Of Student Success In An Upper Division Agriculture Chemistry Class, Maddison V. May

Graduate Theses/Dissertations

To attempt to find what made students successful within a higher division class at Missouri State University’s (MSU) Darr College of Agriculture, de-identified academic records of 172 students enrolled in AGR 300 - Food and Agriculture Chemistry were studied over four semesters. Deidentified data were collected and compared to final letter grade received at the end of the class using correlation coefficients, analysis of variance, and stepwise regression. Analysis of variance was used to evaluate the influence of semester on letter grade. Correlation coefficients were used to determine and evaluate relationships between the variables and final grade. Stepwise regression was …

Determining A Method For Expressing And Purifying Cytochrome P450 4v2: A Protein Involved In Bietti's Crystalline Dystrophy, Cody Lane Turner

Graduate Theses/Dissertations

Within the Cytochrome P450 class of enzymes, there are a group known as the “orphan” cytochromes. The “orphan” classification comes from the poorly understood in vivo functionality and substrate specificity. Cytochrome P450 4V2 (CYP4V2) is one of these “orphans” and belongs to the CYP4 family. The CYP4 family is known for the omega oxidation of endogenous fatty acids. This family is most commonly found on chromosome 1 (CYP4ABXZ). CYP4V2 is unique in that its location is bound to chromosome 4 as discovered by Jiao in 2004. Mutations within the CYP4V2 gene have been associated with the …

The Role Of Liver Sinusoidal Endothelial Cells In Liver Malady Homeostasis, Fatima Cabral

Department of Biochemistry: Dissertations, Theses, and Student Research

Current literature described techniques for the purification of liver cell types through text alone. The techniques described for the isolation of liver sinusoidal endothelial cells as well as hepatocytes described here are modified from a published article in the Journal of Visualized experiments. The video protocol allows for the user to successfully isolate cells as the most difficult parts of the procedure are demonstrated visually. The detection of liver maladies such as the non-alcoholic fatty liver disease, the stage if this disease and differentiation between non-alcoholic and alcoholic fatty liver disease is demonstrated in the development of a unique panel …

Structural Characterization Of Two Large Icosahedral Dna Viruses And Their Capsid Assembly Mechanisms, Yuejiao Xian

Open Access Theses & Dissertations

In the last three decades, many large DNA viruses were discovered and grouped into a loosely defined clade of Nucleocytoplasmic Large DNA Viruses (NCLDVs). NCLDVs infect a wide range of hosts from single cellular protists to large animals. Recently, these viruses were classified as a new phylum of Nucleocytoviricota under the kingdom of Bamfordvirae. The genomes of these Nucleocytoviricota viruses (NCVs) are remarkedly large and complicated, containing many cellular genes from all three domains of life, which raised intensive debates on their evolutionary origins. Despite being classified in the same phylum, their physical structures vary and can be roughly classified …

The Impact Of Microbial Experience On The Murine Innate Immune Response, Cody Thomas Morrison

Masters Theses

The hygiene hypothesis predicts that certain environmental factors shape overall immune system function in animals and humans. While current specific pathogen free (SPF) mouse models are invaluable for studying the immune system, they have limitations for comparison with humans who have microbial exposures throughout their lifetimes. Several studies have shown that the composition of the immune system of SPF mice more closely resembles that of newborns, whereas the immune system from mice exposed to microbial pathogens more closely reflect adult immunity. In this study we have established a model using traditional SPF mice (“clean mice”) and SPF mice that were …