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Full-Text Articles in Biophysics
Combining Simulation And The Mspa Nanopore To Study P53 Dynamics And Interactions, Samantha A. Schultz
Combining Simulation And The Mspa Nanopore To Study P53 Dynamics And Interactions, Samantha A. Schultz
Masters Theses
p53 is a transcription factor and an important tumor suppressor protein that becomes activated due to DNA damage. Because of its role as a tumor suppressor, mutations in the gene that encodes it are found in over 50% of human cancers. The N-terminal transactivation domain (NTAD) of p53 is intrinsically disordered and modulates the function and interactions of p53 in the cell. Its disordered structure allows it to be controlled closely by post-translation modifications that regulate p53’s ability to bind DNA and interact with regulatory binding partners. p53 is an attractive target for developing cancer therapeutics, but its intrinsically disordered …
Atomistic Simulations Of Intrinsically Disordered Protein Folding And Dynamics, Xiping Gong
Atomistic Simulations Of Intrinsically Disordered Protein Folding And Dynamics, Xiping Gong
Doctoral Dissertations
Intrinsically disordered proteins (IDPs) are crucial in biology and human diseases, necessitating a comprehensive understanding of their structure, dynamics, and interactions. Atomistic simulations have emerged as a key tool for unraveling the molecular intricacies and establishing mechanistic insights into how these proteins facilitate diverse biological functions. However, achieving accurate simulations requires both an appropriate protein force field capable of describing the energy landscape of functionally relevant IDP conformations and sufficient conformational sampling to capture the free energy landscape of IDP dynamics. These factors are fundamental in comprehending potential IDP structures, dynamics, and interactions. I first conducted explicit solvent simulations to …
Modulation Of Protein Dynamics By Ligand Binding And Solvent Composition, Richard J. Lindsay
Modulation Of Protein Dynamics By Ligand Binding And Solvent Composition, Richard J. Lindsay
Doctoral Dissertations
Many proteins undergo conformational switching in order to perform their cellular functions. A multitude of factors may shift the energy landscape and alter protein dynamics with varying effects on the conformations they explore. We apply atomistic molecular dynamics simulations to a variety of biomolecular systems in order to investigate how factors such as pressure, the chemical environment, and ligand binding at distant binding pockets affect the structure and dynamics of these protein systems. Further, we examine how such changes should be characterized. We first investigate how pressure and solvent modulate ligand access to the active site of a bacterial lipase …
Uncovering The Roles And Evolved Sequence Grammar Of Hypervariable Intrinsically Disordered Proteins In Bacterial Cell Division, Megan Cohan
McKelvey School of Engineering Theses & Dissertations
Across all domains of life, a defining hallmark of the onset of cell division is the formation of a cytokinetic ring at the center of the cell. Cell division is a tightly controlled process that involves various regulatory factors that modulate the assembly of the cytokinetic ring. In rod-shaped bacteria, the ring is termed the Z-ring after the protein FtsZ, which is foundational to ring formation and is the bacterial homolog of tubulin. Like tubulin, FtsZ is an assembling GTPase, where GTP binding promotes the cooperative assembly into FtsZ polymers that laterally associate to form bundles. While the GTPase domain …
Modeling Disorder In Proteins Yields Insights Into The Evolution Of Stability And Function, Jonathan Huihui
Modeling Disorder In Proteins Yields Insights Into The Evolution Of Stability And Function, Jonathan Huihui
Electronic Theses and Dissertations
The central dogma of molecular biology dictates that a DNA sequence codes for an RNA sequence, which in turn codes for a sequence of amino acids that comprises a protein. Proteins are responsible with performing myriad functions within living organisms and most proteins require a folded structure in order to perform their function. The protein's structure is the direct link from sequence to function. This is known as the sequence - structure - function paradigm. However, this does not mean that the unfolded state is unimportant. In order to properly model the stability of the folded state, one needs to …
Amyloid Proteins And Fibrils Stability, Farbod Mahmoudinobar
Amyloid Proteins And Fibrils Stability, Farbod Mahmoudinobar
Dissertations
Compared to globular proteins that have a stable native structure, intrinsically disordered peptides (IDP) sample an ensemble of structures without folding into a native conformation.One example of IDP is the amyloid-beta(Abeta) protein which is the main constituent of senile plaques in the brain of Alzheimer's patients.Understanding the process by which IDPs undergo structural changes to form oligomers that eventually aggregate into senile plaques/amyloid fibrils may significantly advance the development of novel therapeutic methods to treat neurodegenerative diseases, for which there is no cure to date. This dissertation has two main objectives. The first one is to investigate and identify structural …
Supercharged Models Of Intrinsically Disordered Proteins And Their Utility In Sensing, Peter J. Schnatz
Supercharged Models Of Intrinsically Disordered Proteins And Their Utility In Sensing, Peter J. Schnatz
Dissertations, Theses, and Capstone Projects
In this thesis I show that greatly increasing the magnitude of a protein’s net charge using surface supercharging transforms that protein into a ligand-gated or counterion-gated conformational molecular switch. To demonstrate this I first modified the designed helical bundle hemoprotein H4 using simple molecular modeling, creating a highly charged protein which both unfolds reversibly at low ionic strength and undergoes the ligand-induced folding transition commonly observed in signal transduction by intrinsically disordered proteins in biology. Due to the high surface charge density, ligand binding to this protein is allosterically activated by low concentrations of divalent cations and the polyamine spermine. …
Disorder Levels Of C-Myb Transactivation Domain Regulate Its Binding Affinity To The Kix Domain Of Creb Binding Protein, Anusha Poosapati
Disorder Levels Of C-Myb Transactivation Domain Regulate Its Binding Affinity To The Kix Domain Of Creb Binding Protein, Anusha Poosapati
USF Tampa Graduate Theses and Dissertations
Intrinsically disordered proteins (IDPs) do not form stable tertiary structures like their ordered partners. They exist as heterogeneous ensembles that fluctuate over a time scale. Intrinsically disordered regions and proteins are found across different phyla and exert crucial biological functions. They exhibit transient secondary structures in their free state and become folded upon binding to their protein partners via a mechanism called coupled folding and binding. Some IDPs form alpha helices when bound to their protein partners. We observed a set of cancer associated IDPs where the helical binding segments of IDPs are flanked by prolines on both the sides. …
Determining The Molecular Mechanisms Of Huntington’S Disease Through Multi-Scale Modeling, Kiersten Ruff
Determining The Molecular Mechanisms Of Huntington’S Disease Through Multi-Scale Modeling, Kiersten Ruff
Arts & Sciences Electronic Theses and Dissertations
Huntington’s disease (HD) is associated with a mutational CAG repeat expansion within exon 1 of the huntingtin (Htt) gene. Post-transcriptional processing leads to the generation of N-terminal Htt protein fragments (Htt-NTFs), including those that encompass exon 1 (Httex1). Within Httex1, the CAG-repeat encoded polyglutamine (polyQ) tract is flanked N-terminally by a 17-residue amphipathic stretch (N17) and C-terminally by a 50-residue proline rich (PR) domain. Htt-NTFs, including Httex1, are among the smallest fragments that recapitulate HD pathology in mouse models. However, the direct link between Htt-NTFs with polyQ expansions and neurodegeneration that leads to HD remains unresolved. Despite being a monogenic …
Disorder In Cysteine-Rich Granulin-3 And Its Implication In Alzheimer Disease, Gaurav Ghag
Disorder In Cysteine-Rich Granulin-3 And Its Implication In Alzheimer Disease, Gaurav Ghag
Dissertations
Granulins (GRNs) are a family of small, cysteine-rich proteins that are generated upon proteolytic cleavage of their precursor, progranulin (PGRN) during inflammation. All seven GRNs (1 – 7 or A – G) contain twelve conserved cysteines that form six intramolecular disulfide bonds, rendering this family of proteins unique. GRNs play multiple roles and are involved in a myriad of physiological as well as pathological processes. They are known to a play role in growth and embryonic development, wound healing, and signaling cascades as well as in tumorigenesis. They are also implicated in neurodegenerative diseases like frontotemporal dementia (FTD), Alzheimer disease …
Investigating The Flexibility Of Intrinsically Disordered Proteins In Folding And Binding, Amanda Leilah Debuhr
Investigating The Flexibility Of Intrinsically Disordered Proteins In Folding And Binding, Amanda Leilah Debuhr
Chancellor’s Honors Program Projects
No abstract provided.