Biochemistry, Biophysics, and Structural Biology Commons^™

Amyloid Fibrils Of Human Fgf-1 Induced By Different Detergents, Zeina Ismael Ibrahem Alraawi

Graduate Theses and Dissertations

Nature achieves molecular self-assembly through the ordered growth of nanoscale building blocks with high efficiency to fabricate macromolecular architectures. One example of self- assembly is peptides folding onto protein is one of the most astounding biological self-assembly processes. When proteins aggregate to form amyloid fibers, the secondary structure of the protein converts from its native state to a cross-beta-sheet. Fibroblast growth factors (FGFs) possess an essential role in neuronal survival during development. In addition, they are involved in neural stem cell (NSC) proliferation. Fibroblast growth factors (FGFs) are well known to be synthesized in the central nervous system (CNS) and …

Characterization Of Human Fibroblast Growth Factor 2 Variant To Determine Effects On Structure, Stability, And Cell Proliferation, Ryan Layes

Graduate Theses and Dissertations

Fibroblast growth factors (FGFs) are a family of cell signaling proteins conserved across multiple species. Each individual FGF elicits different cellular functions including, but not limited to, proliferation, migration, differentiation, angiogenesis, and wound healing. One of the most studied members, fibroblast growth factor 2 (FGF2), has demonstrated substantial wound healing capacity in a wide range of tissues including skeletal, muscular, neural, respiratory, epithelial, and cardiovascular. This ability makes FGF2 a potential therapeutic for a wide range of conditions and injuries. However, due to a short half-life at room temperature, therapeutic use of FGF2 is limited. It has been demonstrated that …

Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray

Graduate Theses and Dissertations

Life is remarkable in how resilient it can be. Many organism, classified as ex- tremophiles, can not only survive in extreme environments, but they can thrive in them. In the search for extraterrestrial life, the best candidates to harbor life exist with some kind of extreme condition. Europa, for example, is a favorite for the possibility of accommodating life as we know it within our solar system. Thought there is believed to be a liquid ocean under its icy surface, this habitat would be under immense pressures and high salinity. To best know where to look for extraterrestrial life, it …

Examining The Expression Patterns Of Desulfotalea Psychrophila Dsrab Operon And Pit At Subfreezing Temperatures And Different Concentrations Of Sulfate Salts As A Model For Mars And Icy Worlds Survival And Colonization, Sergio Luis Mosquera Mora

Graduate Theses and Dissertations

Since ancient times, Humanity has been fascinated with the idea of what lies beyond the borders of our planet. Fortunately, the combined efforts of many nations have made it possible to send unmanned spacecraft to orbit planets located close to Earth. These missions have the principal goal to collect data that could help us understand the basic environmental conditions that persist on those planets, or for evidence of past or present life. Equally important, landers and rovers have been successfully deployed to start the in-situ exploration of many planets of the Solar System. Among them, Mars has been extensively studied …

Characterization Of The Influence Of A Small Molecule Inhibitor On Ras-Related Proteins Interactions, Emilio Duverna

Graduate Theses and Dissertations

The Ras superfamily of small G proteins are involved in cell-signaling processes that, if not regulated, may lead to cell multiplication, apoptosis inhibition, and tumorigenesis. They function as molecular switches, which through GTP/GDP exchange cycle, switch on or off cellular activities. Overexpression and/or hyperactivity of these proteins have been linked to many diseases including various cancers. CDC42, a member of the Rho subfamily of the Ras superfamily of small G proteins, participates in the regulation of many cellular processes including cell adhesion, mitosis, and cytoskeletal rearrangements. CDC42 binds to and activates many effector proteins including CDC42-activated kinase (ACK). Abnormal activities …

Preparation Of Proteins And Peptides From Heat-Stabilized Defatted Rice Bran Via Solid State Fermentation And Investigating For Skin Health, Ali A. Bisly

Graduate Theses and Dissertations

Heat-stabilized defatted rice bran (HDRB) is an abundant and inexpensive agro-industrial by-product of rice milling and rice oil extraction process. Furthermore, HDRB is a potential source of proteins. However, the direct protein extraction has low yield of protein due to the impact of heat stabilization and oil extraction process which made the HDRB proteins bound and interact with other components. This research is based on using solid-state fermentation (SSF), which is a natural and cost-effective approach to facilitate protein extraction from HDRB using Bacillus subtilis (natto) Takahashi as a microorganism.

Response surface methodology (RSM) analysis was used with Box-Behnken design …

Engineering Fluorescently Labeled Human Fibroblast Growth Factor One Mutants And Characterizing Their Photophysics Properties Towards Designing Fret Assays, Mamello Mohale

Graduate Theses and Dissertations

Human fibroblast growth factor one (hFGF1) belongs to a family of 22 FGF members produced by fibroblast cells. Cell signaling during physiological processes of angiogenesis and wound healing occurs when hFGF1 binds to its receptor (FGFR). However, when heterogenous homeostasis is not maintained, fibroblast cells exhibit excessive proliferation which can lead to a myriad of cancers. smFRET is an ultrasensitive distant dependent (1-10 nm) technique capable of resolving such heterogeneity in structural dynamics and binding affinities (Kd). Therefore, we successfully designed and characterized fluorescently labeled hFGF1 tracers which span the visible light region of the electromagnetic spectrum for use in …

Investigating Effects Of Microenvironmental Stress On Cell Metabolism Using Multiphoton Imaging, Lisa Rebello

Graduate Theses and Dissertations

Resistance to therapy in cancer is a major cause of poor prognosis in patients. Tumor hypoxia plays an active role in mediating treatment resistance and has been linked to metastases and metastatic potential in cancer. Our research focused on three objectives: i) To understand metabolic effects of chronic and intermittent hypoxia in murine breast cancer cells and its affiliation with metastatic potential ii) To identify the metabolic changes associated with radiation therapy in a panel of radiosensitive and radioresistant human head and neck cancer cells and iii) to monitor the changes in cell metabolism associated with gain of treatment resistance. …

Characterization Of Iron-Sulfur Cluster Biogenesis In Methanogenic Archaea, Thomas Modlin Deere

Graduate Theses and Dissertations

Iron-sulfur (Fe-S) clusters are among the oldest cofactors on the planet, used by proteins in almost all forms of life on Earth to carry out processes ranging from energy transfer to DNA replication. Among the organisms believed to use these Fe-S proteins more extensively than almost any others are the methanogens, an ancient lineage of archaeal microbes that produce methane as a required product of their metabolism. Methane, the primary component of commercial natural gas, is both a potent greenhouse gas and an important fossil fuel. It can also be renewably produced as a biofuel. Biogenic methane is almost entirely …

The Characterization Of Angiopoietin-Like Protein 4 Overexpression In Triple Negative Breast Cancer, Jodi Simeon

Graduate Theses and Dissertations

Triple Negative Breast Cancer (TNBC) is highly invasive and metastatic with approximately 15% of patients developing liver metastases. The primary treatment of metastatic TNBC is chemotherapy, however, there is an increased chance of resistance to this therapeutic technique. If Breast Cancer Liver Metastasis (BCLM) is left untreated most patients survive only 4 to 8 months with a very rare 5-year survival. Therefore, it is imperative to analyze markers and molecular pathways that TNBC cells use to progress, invade, and metastasize to the liver. The aim of this study was to examine the overexpression of angiopoietin-like 4 (ANGPTL4) in TNBC cells …

Evaluating Bioenergetics And Mitochondrial Dynamics In Patient Fibroblasts With Pathogenic Mitochondrial Dna Mutations Causing Leigh Syndrome, Ajibola Bakare

Graduate Theses and Dissertations

Leigh syndrome (LS) is a rare fatal mitochondrial disorder of infants caused by pathogenic mutations in the nuclear (nDNA) or mitochondrial DNA (mtDNA) leading to mitochondrial dysfunction. The extent to which pathogenic mtDNA variants regulate disease severity in LS is not well understood. The heterogeneous nature of this disorder, based in part by complex mitochondrial genetics, and the nuclear and mitochondrial cross-talk has made it particularly challenging to investigate and develop therapies for treating LS . While the prognosis is poor, several studies are underway to understand the pathophysiology of LS. This dissertation provides a comprehensive structural and functional analysis …

A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso

Graduate Theses and Dissertations

Cachexia is a multisystemic and multifactorial syndrome prevalent in cancer patients. It is clinically defined by involuntary loss of >5% weight in a six-month window, despite nutritional interventions. A negative energy balance characterizes cancer cachexia (CC), it is associated with weakness and fatigue in skeletal muscle. Impaired muscle function is associated with lower quality of life in cancer patients. Defects in mitochondrial function are strongly associated with muscle wasting. This study explored muscular contractile function and mitochondrial quality control (MQC) markers in soleus, gastrocnemius, and tibialis anterior (TA) muscles of C26-induced male tumor-bearing mice during a 25-day time course. It …

Host-Parasite Interactions Within Food Webs, Adam Zvanut Hasik

Graduate Theses and Dissertations

Parasitism is one of the most common life history strategies employed in nature, yet the effects of parasites are often thought to be minimal, and the vast majority of studies fail to consider parasites and their effects on host organisms. This is likely a problem, as the magnitude of parasite-mediated effects on their hosts can be quite large. Additionally, the effects of parasites are known to extend beyond the host to affect other species interactions. I used a series of approaches to gain a more integral understanding of host-parasite interactions by studying (1) the effects of parasites on biotic interactions …

The Biochemical Characterization Of Aza197 And A Ras Related Protein Cdc42, Alix Montoya-Beltran

Graduate Theses and Dissertations

Eukaryotic cells contain an extensive amount of GTP/GDP binding proteins. Proteins known as Ras GTPase primary function as a binary switch, where they cycle from an on and off state when GTP or GDP are bound, respectively. They are known to play a critical role in many cellular functions where a dysregulation could potentially lead to oncogenic behavior or other malignancies. In our laboratory, our focus is the study of a Ras related protein Cell division control 42 homolog (Cdc42) which belongs to the Rho subfamily. Cdc42 plays a critical role in many biological signaling processes; therefore, its uncontrol gene …

Dissecting The Cellular Control Of Septin Organization In A Global Cereal Killer, Nawaraj Dulal

Graduate Theses and Dissertations

Rice blast disease, caused by the filamentous fungus Magnaporthe oryzae, destroys sufficient rice each year to feed 60 million people, and is a serious threat to global food security. A wheat-adapted lineage of M. oryzae now poses threat to global wheat production. Rice blast disease is currently controlled using limited fungicides, and the emergence of fungicide resistance within M. oryzae populations is a growing concern. There is a pressing need to identify new classes of fungicides to control the disease, which requires better understanding of the basic biology of the pathogen. To establish disease, M. oryzae forms a specialized dome …

Phenotypic Switching Of Bacterial Cells In Extreme Environments, Sudip Nepal

Graduate Theses and Dissertations

A large number of terrestrial microbial lives thrive in extremes of environmental conditions, including extremes of pressure, temperature, salinity, pH, and a combination of them. For example, all the marine biomass thrive at high hydrostatic pressure depending on depth. The temperature in the ocean can be very high near the hydrothermal vents and salinity and pH depends on the composition of salt in the surrounding areas. On the surface, hot springs, lakes and geysers provide high temperature conditions, while many places are permafrost regions with subzero temperatures. There is an emerging body of work on the viability, genomics, and metagenomics …

Nutritional Supplementation And Skeletal Muscle Health In Chronic Diseases, Hexirui Wu

Graduate Theses and Dissertations

Prevalence of chronic diseases in the United States keeps increasing in recent years. There are approximately four in ten adults having chronic diseases in America. Chronic diseases include obesity, aging, heart diseases, cancer and many others. This thesis mainly focuses on obesity and aging. Skeletal muscle performance is impaired in obesity and aging conditions. One common reason causing this could be higher fat mass and lower muscle mass. However, there is no study showing what pathways are involved in the imbalance of body composition. Therefore, the first objective of the thesis is to determine gene expression of selected pathways in …

A Putative Cystathionine Beta-Synthase Homolog Of Mycolicibacterium Smegmatis Is Involved In De Novo Cysteine Biosynthesis, Saroj Kumar Mahato

Graduate Theses and Dissertations

Mycobacteria include serious pathogens of humans and animals. Mycolicibacterium smegmatis is a non-pathogenic model that is widely used to study core mycobacterial metabolism. This thesis explores mycobacterial pathways of cysteine biosynthesis by generating and study of genetic mutants of M. smegmatis. Published in vitro biochemical studies had revealed three independent routes to cysteine synthesis in mycobacteria involving separate homologs of cysteine synthase, namely CysK1, CysK2, and CysM. However, in vivo data were lacking. The M. smegmatis genome encodes only a CysM homolog and lacks orthologs for CysK1 or CysK2. The gene that codes for CysM is a part of an …

Cloning, Protein Expression, And Characterization Of Interleukin 1 Alpha, Musaab Habeeb Ali Al Ameer

Graduate Theses and Dissertations

Recombinant DNA technology and the ability to produce recombinant proteins have significantly changed the world of pharmaceutical market. Recombinant DNA technology using E. coli cells has successfully produced many therapeutic proteins. In this study, the designed tag Ark-RUBY-tag facilitates rapid, and reproducible purification of recombinant proteins expressed as inclusion bodies in E. coli cells. Purification of Ark-RUBY-fused recombinant protein(s) can be obtained by using imidazole fractions. Target protein can be easily removed from the Ark-RUBY-tag by enzymatic cleavage. Ark-RUBY-fused recombinant proteins can be quantitatively detected using polyclonal antibodies. Ark-RUBY-tag can be used to purify small peptides. By using Ark-RUBY-tag, purified …

Cloning, Expression, Purification And Characterization Of Heparin-Binding Pocket Of Recombinant Fgf1, Quratulayn Ashraf

Graduate Theses and Dissertations

Fibroblast growth factors are polypeptide members of the FGF family, which to date comprises of at least 22 members. They belong to a group of growth factors and are involved in a variety of cellular processes including wound healing, angiogenesis, differentiation and development (organogenesis). Amongst FGF members, human acidic FGF-1 and basic FGF-2 are the most characterized. FGF-1 and FGF-2 are known to share more than 80% sequence similarity and have an identical structural fold. However, their biological roles are quite different. FGFs bind to heparin and heparan sulfate ligands through their heparin-binding pockets. The interactions are primarily electrostatic in …

Natural Variation In Yeast Stress Signaling Reveals Multiple Paths To Similar Phenotypes, Amanda N. Scholes

Graduate Theses and Dissertations

Natural environments are dynamic, and organisms must sense and respond to changing conditions. One common way organisms deal with stressful environments is through gene expression changes, allowing for stress acclimation and resistance. Variation in stress sensing and signaling can potentially play a large role in how individuals with different genetic backgrounds are more or less resilient to stress. However, the mechanisms underlying how gene expression variation affects organismal fitness is often obscure.

To understand connections between gene expression variation and stress defense phenotypes, we have been exploiting natural variation in Saccharomyces cerevisiae stress responses using a unique phenotype called acquired …

Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr

Graduate Theses and Dissertations

Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …

Spatial Reorganization Of Histone-Like Nucleoid Structuring Proteins Caused By Silver Nanoparticles, Meaad Alqahtany

Graduate Theses and Dissertations

Silver nanoparticles (AgNPs) and ions (Ag+) can be the new generation of antibiotics due to their antimicrobial effects against bacteria and other microbes. Many studies have shown that AgNPs and suppress the growth of bacteria and damage the cell walls of the microbes; therefore, treating bacterial cells with AgNPs may be a promising method to terminate multi-resistant bacteria. In this work, the effect of AgNPs with two different surface coatings on the spatial reorganization of histone-like nucleoid structuring (H-NS) proteins in Escherichia coli bacteria was investigated using quantitative super-resolution fluorescence microscopy to understand the toxicity and antimicrobial mechanism of AgNPs. …

Hormone Signaling, Gene Expression, And Mitochondrial Hormone Receptor Expression In Avian Muscle (Cells), Kentu Rushadd Lassiter

Graduate Theses and Dissertations

Mitochondria are vital to the proper growth and function of muscle cells since they’re responsible for the majority of ATP production used for cellular energy. Previous studies have investigated how differences in mitochondrial function affects feed efficiency (FE) in broilers phenotyped for High and Low FE. Low FE broilers have been shown to have increased levels of reactive oxygen species (ROS), thus contributing to higher levels of oxidative stress and damage seen in these birds. Global gene and protein expression studies conducted on breast muscle of the High FE and Low FE phenotypes have suggested that differences in mitochondrial function …

Targeting Sec61Α By Ipomoeassin F Leads To Highly Cytotoxic Effect, Zhijian Hu

Graduate Theses and Dissertations

Ipomoeassin F is a flagship congener of a resin glycoside family that inhibits growth of many tumor cell lines with only single-digital nanomolar IC50 values. However, biological and pharmacological mechanisms of ipomoeassin F have been undefined. To facilitate exploration of the biological and pharmacological properties, we performed sophisticate SAR (Structure–activity relationship) studies of ipomoeassin F to understand its pharmacophore and structure properties so that we can design favorable probes for further biological investigation. By applying appropriate deviates that possess fluorescent groups and similar bio-activity, the target protein was found to be localized in endoplasmic reticulum (ER). Through biotin affinity pull …

Characterization Of A Variant Of Tuberous Sclerosis Complex 2 And Its Interaction With Rheb, Sowmya Sivakumar

Graduate Theses and Dissertations

Protein-protein interactions are vital in maintaining proper function and homeostasis in cells. Some signaling pathways are regulated by G-proteins that work like switches to activate and deactivate pathways. Mutations in these proteins, their effectors or the interaction between proteins may cause dysregulation of signals that can lead to many diseases.

Rheb, Ras homology enriched in brain, is a Ras family GTPase that is vital in regulation of the mTOR (mammalian target of rapamycin) pathway that signals cell proliferation and growth. Due to the low intrinsic GTPase activity of Rheb, a GTPase activating protein (GAP), Tuberous Sclerosis Complex 2 (TSC2) down …

Mitochondrial Mrna Translation Is Required For Maintenance Of Oxidative Capacity, David Lee

Graduate Theses and Dissertations

Oxidative metabolism is required to produce adequate energy to sustain human life. A primary example of deteriorating oxidative capacity is seen in the cardiac musculature during chronic heart failure. This suggests that by improving oxidative potential, chronic heart disease could be mitigated and one approach to accomplish this may be through targeting the mt-mRNA translation system. Purpose: This investigation’s purpose was to characterize disruptions in mt-mRNA translation machinery in multiple forms of cardiomyopathy and to determine if mitochondrial mRNA translation initiation factor (mtIF2) is necessary to maintain oxidative capacity in cardiomyocytes. Methods Using a combination of animal and cell culture …

Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling, John A. Handley

Graduate Theses and Dissertations

The United States poultry industry generated 38.6 billion pounds (17,500 metric ton) of meat in 2014 which averaged to 121 pounds (55 kg) per individual of the U.S that same year. Of that meat generated by the poultry industry, an estimated 1 million cases of Salmonellosis will occur. Out of the 1 million cases approximately 40, 000 to 50,000 will be confirmed cases by the CDC. Recently, the USDA has requested changes in the inspection process and are currently allowing processors more freedom to utilize innovation to drive the increase in safer and more desirable foods. The new standards set …

Detection Of Survival And Proliferation Of Sulfate Reducers Under Simulated Martian Atmospheric And Soil Conditions, Sergio Mosquera Mora

Graduate Theses and Dissertations

Numerous studies have tried to determine the survivability and proliferation of microorganisms under simulated Martian conditions. Furthermore, most of them have been focused on the ability of these microbes to cope with high brines’ salt (NaCl) concentrations inherent of the Martian surface. However, there are not studies related to the ability of bacteria to survive on subsurface environments that have increasing concentrations of sulfate compounds. For this research, a group of microorganisms known as sulfate-reducing bacteria or simply sulfate reducers were chosen due to their ability to use sulfate compounds as terminal electron acceptors to produce metabolic energy, their tolerance …

Cellular Mechanisms Of Ionoregulation In The Gill Of Japanese Medaka And Rainbow Trout, Rebecca Jo Bollinger

Graduate Theses and Dissertations

Euryhaline fishes are capable of adapting to a wide range of salinities such as freshwater, brackish water or seawater. Through the combined effort of the gill, kidney and intestine, they are able to osmoregulate to maintain a constant internal hydromineral balance. As the gill is in direct contact with the external environment, it is continuously working to maintain ion and acid/base balance, gas exchange and eliminate nitrogenous waste. Fish in freshwater are subjected to osmotic water gain and diffusional ion loss across the gill and experience the opposite in seawater. Therefore, the gill exhibits extreme plasticity when experiencing a change …