Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- 4-HNE (1)
- AMPKα (1)
- Adaptor hierarchy (1)
- Adiposity (1)
- Adsorption mechanism (1)
-
- Age-Related Macular Degeneration (1)
- Apoptosis (1)
- Bacteria (1)
- Bacterial cell cycle (1)
- Biophysical Self-Assembly (1)
- Carbon nanotubes (1)
- Caspase (1)
- Caspases (1)
- Caulobacter (1)
- Cell division (1)
- Cell-penetrating peptides (1)
- Chromosome (1)
- Click Chemistry (1)
- ClpXP (1)
- ClyA (1)
- Collagen (1)
- Community proteomics (1)
- Conformational dynamics (1)
- Cysteine (1)
- Cysteine protease (1)
- Cytokinesis (1)
- De novo peptide sequencing (1)
- Denitrification (1)
- Droplet-interface bilayers (1)
- Drug discovery (1)
Articles 1 - 19 of 19
Full-Text Articles in Life Sciences
Bioinformatic And Experimental Approaches For Deeper Metaproteomic Characterization Of Complex Environmental Samples, Ramsunder Mahadevan Iyer
Bioinformatic And Experimental Approaches For Deeper Metaproteomic Characterization Of Complex Environmental Samples, Ramsunder Mahadevan Iyer
Doctoral Dissertations
The coupling of high performance multi-dimensional liquid chromatography and tandem mass spectrometry for characterization of microbial proteins from complex environmental samples has paved the way for a new era in scientific discovery. The field of metaproteomics, which is the study of protein suite of all the organisms in a biological system, has taken a tremendous leap with the introduction of high-throughput proteomics. However, with corresponding increase in sample complexity, novel challenges have been raised with respect to efficient peptide separation via chromatography and bioinformatic analysis of the resulting high throughput data. In this dissertation, various aspects of metaproteomic characterization, including …
Investigating The Regulation Of Indole-3-Acetic Acid Production By The Plant Associated Microbe Pantoea Sp. Yr343, Kasey Noel Estenson
Investigating The Regulation Of Indole-3-Acetic Acid Production By The Plant Associated Microbe Pantoea Sp. Yr343, Kasey Noel Estenson
Doctoral Dissertations
The auxin indole-3-acetic acid (IAA) plays a central role in plant growth and development and many plant-associated microbes produce IAA. Several IAA biosynthetic pathways have been identified in microbes which use the precursor tryptophan. Pantoea sp. YR343, which was isolated from the Populus deltoides rhizosphere, is a robust plant root colonizer that produces IAA. Using genomic and metabolomics analyses, we predicted that the indole-3-pyruvate (IPA) pathway is the major pathway in Pantoea sp. YR343 for IAA production. To better understand IAA biosynthesis and the effects of IAA exposure on cell physiology, we performed proteomics on Pantoea sp. YR343 grown in …
Design And Synthesis Of Analogs Of Myo-Inositol, Serine, And Cysteine To Enable Chemical Biology Studies, Tanei J. Ricks
Design And Synthesis Of Analogs Of Myo-Inositol, Serine, And Cysteine To Enable Chemical Biology Studies, Tanei J. Ricks
Doctoral Dissertations
Phosphorylated myo-inositol compounds including inositol phosphates (InsPs) as well as the phosphatidylinositol polyphosphate lipids (PIPns) are critical biomolecules that regulate many of the most important biological processes and pathways. They are aberrant in many disease states due to their regulatory function. The same is true of the phospholipid phosphatidylserine (PS) which can serve as a marker to begin apoptosis. However, the full scope of activities of these structures is not clear, particularly since techniques that enable global detection and analysis of the production of these compounds spatially and temporally are lacking. With all of these obstacles in …
Dissecting Molecular Pathways That Ensure Proper Chromosome Segregation And Cell Division, Anna Ye
Dissecting Molecular Pathways That Ensure Proper Chromosome Segregation And Cell Division, Anna Ye
Doctoral Dissertations
Equal segregation of the genome is a prerequisite for cell survival. During cell division the duplicated DNA is compacted into chromosomes and a multi-protein macrostructure, known as the kinetochore (Kt), is assembled on each copy of compacted DNA. Simultaneously, the mitotic spindle, which is made up of microtubules (MTs), is built to facilitate the equal distribution of the chromosomes between the resulting daughter cells. Kinetochores mediate the interaction between the MTs and the chromosomes, properly positioning them for segregation. To ensure that the DNA is equally divided in every cell division, cells have built a surveillance system to detect any …
Imidacloprid, A Neonicotinoid Insecticide, Impairs Lipid And Glucose Metabolism, Quancai Sun
Imidacloprid, A Neonicotinoid Insecticide, Impairs Lipid And Glucose Metabolism, Quancai Sun
Doctoral Dissertations
Emerging evidence suggests that environmental pollutants, including insecticides, are linked to excessive weight gain and altered glucose homeostasis. However, there is currently limited knowledge regarding the biochemical mechanisms by which exposure to insecticides contribute to obesity and its associated pathologies. We first studied the influence of fipronil (a phenylpyrazole family insecticide) on 3T3-L1 adipogenesis. Recently imidacloprid, a neonicotinoid insecticide, was reported to potentiate adipogenesis and insulin resistance in vitro. The current studies also determined the effects of imidacloprid exposure and its interaction with dietary fat in the development of adiposity and insulin resistance using both male and female C57BL/6J …
Regulated Proteolysis Of Dnaa Coordinates Cell Growth With Stress Signals In Caulobacter Crescentus, Jing Liu
Regulated Proteolysis Of Dnaa Coordinates Cell Growth With Stress Signals In Caulobacter Crescentus, Jing Liu
Doctoral Dissertations
DNA replication is an essential process in all domains of life. Replication must be precisely regulated, especially at the step of initiation. In bacteria, the replication initiator DnaA is regulated by multiple post-translational regulations to ensure timely replication. Caulobacter crescentus has the most strict replication regulation that DNA only replicates once per cell cycle, and proteolysis of DnaA identified in this species is the only irreversible way to inhibit DnaA, suggesting it might be pivotal to restricting DNA replication. However, the responsible protease(s) and mechanism for its degradation remain unclear since its first discovery in 2005. In this thesis, I …
Pore Forming Protein Assembly And The Use In Nanopore Sensing: A Study On E. Coli Proteins Clya And Ompg, Monifa Fahie
Pore Forming Protein Assembly And The Use In Nanopore Sensing: A Study On E. Coli Proteins Clya And Ompg, Monifa Fahie
Doctoral Dissertations
Pore forming proteins are typically the proteins that form channels in membranes. They have several roles ranging from molecule transport to triggering the death of a cell. This work focuses on two E. coli pore forming proteins that have vastly differing roles in nature. Outer membrane protein G (OmpG) is an innocuous β-barrel porin while Cytolysin A (ClyA) is an α-helical pore forming toxin. For OmpG we probed its potential to be a nanopore sensor for protein detection and quantification. A small high affinity ligand, biotin, was covalently attached to loop 6 of OmpG and used to capture biotin-binding proteins. …
Detection, Diversity, And Evolution Of Fungal Nitric Oxide Reductases (P450nor), Steven Adam Higgins
Detection, Diversity, And Evolution Of Fungal Nitric Oxide Reductases (P450nor), Steven Adam Higgins
Doctoral Dissertations
Nitrous oxide (N2O) is a gas responsible for significant ozone layer depletion and contributes to greenhouse effects in Earth’s atmosphere. N2O is primarily generated by denitrification, whereby nitrate (NO3-) or nitrite (NO2-) is converted to gaseous N2O or N2. Teragram quantities of N2O are emitted annually from agricultural soils treated with nitrogenous fertilizers due to the activity of soil microbiota. Although bacteria and fungi harbor genes permitting denitrification, fungi lack NosZ, an enzyme responsible for reducing N2O into inert N2 gas. Historically, scientists have linked fungi …
Mechanistic Studies Of Peptide-Mediated Protein Transport Across Droplet-Interface Bilayers, Jing Huang
Mechanistic Studies Of Peptide-Mediated Protein Transport Across Droplet-Interface Bilayers, Jing Huang
Doctoral Dissertations
Pep-1 is a promising peptide tool that delivers proteins and peptides into cells with conserved bioactivity. Pep-1 has great potential because of the high efficiency and lack of toxicity. The mechanism of Pep-1-mediated transport is not fully understood. In my thesis, droplet-interface bilayer (DIB) has been used for the mechanistic studies of Pep-1. Here, DIB is developed for different functions such as quantitation of protein translocation, solution exchange to a formed bilayer and simultaneous observation of multiple membranes. Research work on Pep-1 with DIB reveals that the negative charge of the inner membrane leaflet plays a significant role in promoting …
Probing The Domain Architecture And Structural Dynamics Of Caspase-6 For Its Specific Regulation, Kevin Buadlart Dagbay
Probing The Domain Architecture And Structural Dynamics Of Caspase-6 For Its Specific Regulation, Kevin Buadlart Dagbay
Doctoral Dissertations
Caspases are cysteine aspartate proteases that direct programmed cell death in multicellular organisms. Activation of caspases is tightly regulated to secure maintenance of cellular homeostasis. The aberrant regulation of caspases can act as molecular triggers for a range of diseases from cancer to neurodegeneration. The detailed exploration of caspase structure, dynamics, function, and regulation is crucial to better understand and precisely control their cellular functions. This body of work specifically provides a multi-level understanding of the unique structural dynamics and regulation of caspase-6, the function of which is implicated in Alzheimer’s and Huntington’s diseases. A detailed map …
Relationship Between Structure And Function In Nickel Proteins And Enzymes, Carolyn Carr
Relationship Between Structure And Function In Nickel Proteins And Enzymes, Carolyn Carr
Doctoral Dissertations
Nickel is a rarely used but biologically important metal that is utilized in all three domains of life. In nickel utilizing organisms there is a corresponding trafficking system specifically designed to capture nickel, deliver, and export excess nickel to prevent toxic effects. It is critical to understand the mechanisms by which organisms achieve metal selectivity to duplicate or disrupt this process for the benefit of human health and to further understanding of regulation mechanisms in biology. RcnR is a Ni(II) and Co(II) responsive transcriptional regulator in E. coli. The research reported in this dissertation focuses on the relationship between …
The Key Question In Symbiotic Nitrogen Fixation: How Does Host Maintain A Bacterial Symbiont?, Onur Oztas
The Key Question In Symbiotic Nitrogen Fixation: How Does Host Maintain A Bacterial Symbiont?, Onur Oztas
Doctoral Dissertations
The fact that plants cannot use nitrogen in the gaseous form makes them dependent on the levels of usable nitrogen forms in the soil. Legumes overcome nitrogen limitation by entering a symbiotic association with rhizobia, soil bacteria that convert atmospheric nitrogen into usable ammonia. In root nodules, bacteria are internalized by host plant cells inside an intracellular compartment called the symbiosome where they morphologically differentiate into nitrogen-fixing forms by symbiosome-secreted host proteins. In this project, I explained the host proteins required to maintain bacterial symbionts and described their delivery to the symbiosome. I showed that the SYNTAXIN 132 (SYP132) gene …
Vitreous Gel Physics, Svetlana Morozova
Vitreous Gel Physics, Svetlana Morozova
Doctoral Dissertations
The transparent vitreous, which fills the posterior cavity of the eye, is incredibly engineered. The charged polyelectrolyte hyaluronic acid (HA) network swells to maintain the pressure in the eye, while stiff collagen type II bundles help absorb any external mechanical shock. Our investigations have contributed to a few key developments related to the physical properties of the vitreous: (1) The stiff collagen network that supports the soft gel network is self-assembled from single triple-helix collagen proteins. Electrostatic interactions drive this assembly, such that the size and concentration are optimized at physiological salt concentrations. The width of the assemblies remarkably changes …
Mechanistic Studies Of Proton Gradient-Driven Protein Translocation By Droplet-Interface Bilayer Techniques, En-Hsin Lee
Mechanistic Studies Of Proton Gradient-Driven Protein Translocation By Droplet-Interface Bilayer Techniques, En-Hsin Lee
Doctoral Dissertations
Transmembrane proton gradient plays a fundamental role in protein translocation across cellular membranes, including the transport of secreted enzymes from bacterial pathogens into host cells. Much attention has been devoted to understanding the machinery of such delivery and how it functions. Over the past decade, translocation of anthrax toxin has been widely studied not only because of its central role in the deadly pathogenesis of Bacillus anthracis, but also because that it is one of the most tractable toxins and thus serves as an attractive model for studying the translocation machinery that is dependent on proton gradient across membrane. …
Adaptors At Work: Regulation Of Bacterial Proteolysis By Adaptor Hierarchies, Kamal Joshi
Adaptors At Work: Regulation Of Bacterial Proteolysis By Adaptor Hierarchies, Kamal Joshi
Doctoral Dissertations
Regulated protein degradation is essential for all life. Bacteria use energy-dependent proteases to regulate protein degradation. Recognition of a substrate is enabled by the inherent specificity of the protease and by the use of adaptor proteins that widen the spectrum of recognized substrates. In Caulobacter crescentus, the timed destruction of many regulators including CtrA by the ClpXP protease drives cell cycle progression. Although, in a test tube, ClpXP can degrade CtrA by itself and does not need any helping factors, additional factors such as CpdR, RcdA and PopA are required in vivo. Understanding how these factors modulate protease …
The Statistical Dynamics Of Nonequilibrium Control, Grant Murray Rotskoff '09
The Statistical Dynamics Of Nonequilibrium Control, Grant Murray Rotskoff '09
Doctoral Dissertations
Living systems, even at the scale of single molecules, are constantly adapting to changing environmental conditions. The physical response of a nanoscale system to external gradients or changing thermodynamic conditions can be chaotic, nonlinear, and hence difficult to control or predict. Nevertheless, biology has evolved systems that reliably carry out the cell’s vital functions efficiently enough to ensure survival. Moreover, the development of new experimental techniques to monitor and manipulate single biological molecules has provided a natural testbed for theoretical investigations of nonequilibrium dynamics. This work focuses on developing paradigms for both understanding the principles of nonequilibrium dynamics and also …
Exploitation And Regulation Of Apoptotic Caspases, Scott Eron
Exploitation And Regulation Of Apoptotic Caspases, Scott Eron
Doctoral Dissertations
Caspases are the cysteine proteases that govern apoptotic cell death. The regulation of these enzymes is critical in order to restrain their death-inducing capabilities until the appropriate moment. Infidelity of caspase regulation and activation underlies a plethora of human diseases ranging from cancer to neurodegeneration. This establishes a pressing need for comprehensive studies of the apoptotic caspases in order to understand all aspects of their regulation, activation, substrate preferences, structure, and function. A detailed structural view of caspase regulation would have lasting implications for future therapeutic avenues targeting caspase function or apoptosis. This dissertation chronicles caspase regulation by phosphorylation as …
Adsorption Of Biomolecules On Carbon-Based Nanomaterial As Affected By Surface Chemistry And Ionic Strength, Peng Du
Doctoral Dissertations
In the first project, we examined adsorption of bovine serum albumin (BSA) and lysozyme (LYZ) on carboxylated (CM), hydroxylated (HM) and graphitized (GM) multi-wall carbon nanotubes (CNTs). All adsorption isotherms were fitted well with Langmuir model. Maximum adsorption capacities (mg/g) followed: HM>CM>GM for both BSA and LYZ, which positively related to the surface areas of the three CNTs. However, after surface area normalization, adsorption capacity (mg/m2) followed: HM>GM>CM for BSA and GM>CM>HM for LYZ, indicating that functional groups and hydrophobicity of CNTs also contributed to protein adsorption. In addition, adsorption of LYZ …
The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang
The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang
Doctoral Dissertations
"Age-related macular degeneration (AMD) is a leading cause of irreversible blindness among adults, age 60 and older, in developed countries. While oxidative stress is implicated in the pathogenesis of AMD, clinical studies have shown that dietary antioxidants can delay progression of AMD. Currently, there is no FDA-approved treatment for AMD. Therefore, we hypothesized that N-acetylcysteine amide (NACA), a thiol antioxidant, would protect retinal pigment epithelium and impede the progression of retinal degeneration. The goal of this work was to evaluate the efficacy of NACA in preventing retinal pigment epithelial cell and photoreceptor death in AMD models. To achieve this, we …