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Designing A Reactive Warhead To Bind And Inhibit Pseudomonas Aeruginosa’S Periplasmic Protein, Inhibitor Of Vertebrate Lysozyme, Leah Greinke 2021 Kennesaw State University

Designing A Reactive Warhead To Bind And Inhibit Pseudomonas Aeruginosa’S Periplasmic Protein, Inhibitor Of Vertebrate Lysozyme, Leah Greinke

Master of Science in Chemical Sciences Theses

Pseudomonas aeruginosa is a Gram-negative bacterium commonly found throughout the environment. It is a significant cause of disease and mortality in immunodeficient patients such as those suffering from cystic fibrosis (CF). Due to the emerging antibiotic resistance of P. aeruginosa, it is becoming increasingly more challenging to treat an infection by traditional means. Further complicating treatment, P. aeruginosa secretes a protein known as Inhibitor of Vertebrate Lysozyme (PaIVY) that binds to and inhibits C-type lysozyme, thus preventing the degradation of the bacterium. A reactive chemical warhead was synthesized from a rhenium(I) tricarbonyl derivative inorder to bind to and irreversibly ...


Analyzing The Effects Of E-Hook Peptides On Kinesin-1, Ashton Ward Murrah, Baylee Hope Howard 2021 University of Mississippi

Analyzing The Effects Of E-Hook Peptides On Kinesin-1, Ashton Ward Murrah, Baylee Hope Howard

Honors Theses

Cancer is the second leading cause of death in the United States. Cancerous growth is a result of oncogenes, or mutated genes that increase the rate of cell division in an uncontrolled manner. Cell division, which consists of mitosis and cytokinesis phases, is dependent upon the active movement of kinesin motor proteins along microtubules to rearrange the cytoskeleton for equitable distribution of genetic material to daughter cells. As kinesins are vital to this process, if we could prevent kinesin from binding to the microtubules, cell division would cease.

The goal of this study is to develop a method to prevent ...


Ischemic Stroke Thrombus Characterization Through Quantitative Magnetic Resonance Imaging, Spencer D. Christiansen 2021 The University of Western Ontario

Ischemic Stroke Thrombus Characterization Through Quantitative Magnetic Resonance Imaging, Spencer D. Christiansen

Electronic Thesis and Dissertation Repository

Stroke is a pervasive, devastating disease and remains one of the most challenging conditions to treat. In particular, risk of recurrence is dramatically heightened after a primary stroke and requires urgent preventative therapy to effectively mitigate. However, the appropriate preventative therapy depends on the underlying source of the stroke, known as etiology, which is challenging to determine promptly. Current diagnostic tests for determining etiology underwhelm in both sensitivity and specificity, and in as much as 35% of cases etiology is never determined. In ischemic stroke, the composition of the occluding thrombus, specifically its red blood cell (RBC) content, has been ...


Investigating Structural Proteins By Light Scattering, Uma Nudurupati 2021 University of Massachusetts Amherst

Investigating Structural Proteins By Light Scattering, Uma Nudurupati

Masters Theses

This thesis evaluates the organization of the structural proteins, Human Gamma D crystallin and Collagen type II, into higher-order structures using light scattering. Specifically, it evaluates the natures of incipient aggregation in Human Gamma D crystallin and the nature of its interactions with CAPEGn, an electrostatic blocker. Additionally, this thesis evaluates whether Collagen type II growth kinetics follows Classical nucleation theory.


Swi/Snf Senses Carbon Starvation With A Ph-Sensitive Low Complexity Sequence [Preprint], J. Ignacio Gutiérrez, Gregory P. Brittingham, Yonca Karadeniz, Kathleen D. Tran, Arnob Dutta, Alex S. Holehouse, Craig L. Peterson, Liam J. Holt 2021 University of California - Berkeley

Swi/Snf Senses Carbon Starvation With A Ph-Sensitive Low Complexity Sequence [Preprint], J. Ignacio Gutiérrez, Gregory P. Brittingham, Yonca Karadeniz, Kathleen D. Tran, Arnob Dutta, Alex S. Holehouse, Craig L. Peterson, Liam J. Holt

University of Massachusetts Medical School Faculty Publications

It is increasingly appreciated that intracellular pH changes are important biological signals. This motivates the elucidation of molecular mechanisms of pH-sensing. We determined that a nucleocytoplasmic pH oscillation was required for the transcriptional response to carbon starvation in S. cerevisiae. The SWI/SNF chromatin remodeling complex is a key mediator of this transcriptional response. We found that a glutamine-rich low complexity sequence (QLC) in the SNF5 subunit of this complex, and histidines within this sequence, were required for efficient transcriptional reprogramming during carbon starvation. Furthermore, the SNF5 QLC mediated pH-dependent recruitment of SWI/SNF to a model promoter in vitro ...


Relaxed Tarantula Skeletal Muscle Has Two Atp Energy-Saving Mechanisms, Weikang Ma, Sebastian Duno-Miranda, Thomas Irving, Roger W. Craig, Raul A. Padron 2021 Illinois Institute of Technology

Relaxed Tarantula Skeletal Muscle Has Two Atp Energy-Saving Mechanisms, Weikang Ma, Sebastian Duno-Miranda, Thomas Irving, Roger W. Craig, Raul A. Padron

Radiology Publications

Myosin molecules in the relaxed thick filaments of striated muscle have a helical arrangement in which the heads of each molecule interact with each other, forming the interacting-heads motif (IHM). In relaxed mammalian skeletal muscle, this helical ordering occurs only at temperatures > 20 degrees C and is disrupted when temperature is decreased. Recent x-ray diffraction studies of live tarantula skeletal muscle have suggested that the two myosin heads of the IHM (blocked heads [BHs] and free heads [FHs]) have very different roles and dynamics during contraction. Here, we explore temperature-induced changes in the BHs and FHs in relaxed tarantula skeletal ...


Cryo-Tem Simulations Of Amorphous Radiation-Sensitive Samples Using Multislice Wave Propagation [Preprint], Benjamin A. Himes, Nikolaus Grigorieff 2021 University of Massachusetts Medical School

Cryo-Tem Simulations Of Amorphous Radiation-Sensitive Samples Using Multislice Wave Propagation [Preprint], Benjamin A. Himes, Nikolaus Grigorieff

University of Massachusetts Medical School Faculty Publications

Image simulation plays a central role in the development and practice of high-resolution electron microscopy, including transmission electron microscopy of frozen-hydrated specimens (cryo-EM). Simulating images with contrast that matches the contrast observed in experimental images remains challenging, especially for amorphous samples. Current state-of-the-art simulators apply post hoc scaling to approximate empirical solvent contrast, attenuated image intensity due to specimen thickness, and amplitude contrast. This practice fails for images that require spatially variable scaling, e.g., simulations of a crowded or cellular environment. Modeling both the signal and the noise accurately is necessary to simulate images of biological specimens with contrast ...


The N Terminus Of Myosin-Binding Protein C Extends Toward Actin Filaments In Intact Cardiac Muscle, Sheema Rahmanseresht, Kyoung H. Lee, Thomas S. O'Leary, James W. McNamara, Sakthivel Sadayappan, Jeffrey Robbins, David M. Warshaw, Roger W. Craig, Michael J. Previs 2021 University of Vermont

The N Terminus Of Myosin-Binding Protein C Extends Toward Actin Filaments In Intact Cardiac Muscle, Sheema Rahmanseresht, Kyoung H. Lee, Thomas S. O'Leary, James W. Mcnamara, Sakthivel Sadayappan, Jeffrey Robbins, David M. Warshaw, Roger W. Craig, Michael J. Previs

Radiology Publications

Myosin and actin filaments are highly organized within muscle sarcomeres. Myosin-binding protein C (MyBP-C) is a flexible, rod-like protein located within the C-zone of the sarcomere. The C-terminal domain of MyBP-C is tethered to the myosin filament backbone, and the N-terminal domains are postulated to interact with actin and/or the myosin head to modulate filament sliding. To define where the N-terminal domains of MyBP-C are localized in the sarcomere of active and relaxed mouse myocardium, the relative positions of the N terminus of MyBP-C and actin were imaged in fixed muscle samples using super-resolution fluorescence microscopy. The resolution of ...


Third Harmonic Generation: A Method For Visualizing Myelin In The Murine Cerebral Cortex, Michael Redlich 2021 The Graduate Center, City University of New York

Third Harmonic Generation: A Method For Visualizing Myelin In The Murine Cerebral Cortex, Michael Redlich

Dissertations, Theses, and Capstone Projects

Here we present the use of Third Harmonic Generation (THG) for the label-free imaging of myelinated axons in the murine cerebral cortex. Myelin plays an important role in the processes of learning and disease. However, much of the myelin biology research thus far has focused on white matter tracts where myelin is more visible. Much is still unknown, particularly with regard to myelin in gray matter. First, we engage in THG microscopy using an optical parametric oscillator pumped by a titanium-sapphire laser to demonstrate the utility of the technique for imaging myelin in vivo. Second, we investigate the use of ...


The C. Neoformans Cell Wall: A Scaffold For Virulence, Christine Chrissian 2021 The Graduate Center, City University of New York

The C. Neoformans Cell Wall: A Scaffold For Virulence, Christine Chrissian

Dissertations, Theses, and Capstone Projects

Cryptococcus neoformans is a globally distributed opportunistic fungal pathogen and the causative agent of life threatening cryptococcal meningoencephalitis in immunocompromised individuals, resulting in ~180,000 deaths each year worldwide. A primary virulence-associated trait of this organism is the production of melanin. Melanins are a class of diverse pigments produced via the oxidation and polymerization of aromatic ring compounds that have a characteristically complex, heterogenous, and amorphous structure. They are synthesized by representatives of all biological kingdoms and share a multitude of remarkable properties such as the ability to absorb ultraviolet (UV) light and protect against ionizing radiation. Melanin production in ...


Direct Recruitment Of Eif4gi And/Dap5 To The 5' Utr Of A Subset Of Human Mrna Drives Their Cap-Independent Translation, Solomon A. Haizel 2021 The Graduate Center, City University of New York

Direct Recruitment Of Eif4gi And/Dap5 To The 5' Utr Of A Subset Of Human Mrna Drives Their Cap-Independent Translation, Solomon A. Haizel

Dissertations, Theses, and Capstone Projects

During unfavorable cellular conditions (e.g., tumor hypoxia, viral infection, nutrient deprivation, etc.), the canonical, cap-dependent translation initiation pathway in human cells is suppressed by sequestration of the cap-binding protein, eukaryotic initiation factor(eIF) 4E, by 4E-binding proteins. Circumvention of cap-dependent translation shutdown has been linked to tumor development and cancer progression. The stress-induced repression of cap-dependent translation has also been correlated with increased eIF4GI and its homolog, Death Associated Protein 5 (DAP5) expression levels, suggesting these factors have a role in cap-independent translation. Despite several evidence pointing towards a link upregulation of eIF4GI and /DAP5 levels during stress conditions ...


On The Structure And Function Of Mitochondrial Uncoupling Proteins: The Case Of Ucp2, Afshan Ardalan 2021 Wilfrid Laurier University

On The Structure And Function Of Mitochondrial Uncoupling Proteins: The Case Of Ucp2, Afshan Ardalan

Theses and Dissertations (Comprehensive)

Uncoupling proteins (UCPs) are regulated proton transporters of the mitochondrial inner membrane. UCP-mediated proton leak negatively impacts the rate of ATP synthesis. Despite the importance of their physiological role(s) in certain tissues, molecular aspects of UCPs’ structure-function relationships are not fully understood. The current study explores the tertiary and quaternary structure of UCP2, as well as its proton transport mechanism in lipid membranes. The proteins were expressed in the E. coli inner membrane, purified and reconstituted into liposomes. Proteins were characterized by semi-native SDS-PAGE. Circular dichroism spectroscopy (CD) and fluorescence quenching assays were utilized to study the conformation of ...


Physical Models Of Living Systems 2nd Ed, New Chapter: Demographic Variation In Epidemic Spread, Philip C. Nelson 2020 University of Pennsylvania

Physical Models Of Living Systems 2nd Ed, New Chapter: Demographic Variation In Epidemic Spread, Philip C. Nelson

Department of Physics Papers

This chapter extends the first edition of Physical Models of Living Systems (WH Freeman 2015). This preliminary version is made freely available as-is in the hope that it will be useful.


Quantifying Anticancer Drug Doxorubicin Binding To Dna Using Optical Tweezers, Zachary Ells 2020 Bridgewater State University

Quantifying Anticancer Drug Doxorubicin Binding To Dna Using Optical Tweezers, Zachary Ells

Honors Program Theses and Projects

Doxorubicin is a successful anticancer drug approved for use in the 1970s and is considered to be one of the most effective cancer treatment methods today. Although Doxorubicin has positive survival statistics it has very negative side effects in many cases. Bleeding from the soles of the palms and feet, along with excruciating pain is often exhibited through the administration of this drug. Based on the preliminary findings utilizing optical tweezers we anticipate that this study will provide critical information about the drug binding mechanism. Single molecule biophysics techniques have provided useful insight into the DNA-binding mechanisms of small molecules ...


Controlled Membrane Remodeling By Nanospheres And Nanorods: Experiments Targeting The Design Principles For Membrane-Based Materials, Sarah Zuraw-Weston 2020 University of Massachusetts Amherst

Controlled Membrane Remodeling By Nanospheres And Nanorods: Experiments Targeting The Design Principles For Membrane-Based Materials, Sarah Zuraw-Weston

Doctoral Dissertations

In this thesis we explore two experimental systems probing the interactions of nanoparticles with lipid bilayer membranes. Inspired by the ability of cell membranes to alter their shape in response to bound particles, we report two experimental studies: one of nanospheres the other of long, slender nano-rods binding to lipid bilayer vesicles and altering the membrane shape. Our work illuminates the role of particle geometry, particle concentration, adhesion strength and membrane tension in how membrane morphology is determined. We combine giant unilamellar vesicles with oppositely charged nanoparticles, carefully tuning adhesion strength, membrane tension and particle concentration.

In the case of ...


Micro-Physiological Models To Mimic Mucosal Barrier Complexity Of The Human Intestine In Vitro, Abhinav Sharma 2020 University of Massachusetts Amherst

Micro-Physiological Models To Mimic Mucosal Barrier Complexity Of The Human Intestine In Vitro, Abhinav Sharma

Doctoral Dissertations

The mucosal barrier in the intestine is vital to maintain selective absorption of nutrients while protecting internal tissues and maintaining symbiotic relationship with luminal microbiota. This bio-barrier consists of a cellular epithelial barrier and an acellular mucus barrier. Secreted mucus regulates barrier function via in situ biochemical and biophysical interaction with luminal content that continually evolves during digestion and absorption. Increasing evidence suggests that a mucus barrier is indispensable to maintain homeostasis in the gastrointestinal tract. However, the importance of mucus barrier is largely underrated for in vitro mucosal tissue modeling. The major gap is the lack of experimental material ...


Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace 2020 The University of Maine

Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace

Electronic Theses and Dissertations

Influenza virus, colloquially known as the flu, is an acute respiratory disease that infects several millions of individuals each year in the U.S. and kills tens of thousands of those infected. Yearly viral vaccines are widely available, however, due to the virus’s high mutation rate, their efficacy varies greatly. Due to the variability in vaccine efficiency against seasonal influenza, and the potential for even more pathogenic versions of influenza to emerge at any time, there is a high demand for a universal treatment option.

Influenza virus hijacks a variety of host cell components in order to replicate. The ...


Viral Packaging Atpases Utilize A Glutamate Switch To Couple Atpase Activity And Dna Translocation [Preprint], Joshua Pajak, Rockney Atz, Brendan J. Hilbert, Marc C. Morais, Brian A. Kelch, Paul Jardine 2020 Duke University

Viral Packaging Atpases Utilize A Glutamate Switch To Couple Atpase Activity And Dna Translocation [Preprint], Joshua Pajak, Rockney Atz, Brendan J. Hilbert, Marc C. Morais, Brian A. Kelch, Paul Jardine

University of Massachusetts Medical School Faculty Publications

Many viruses utilize ringed packaging ATPases to translocate double-stranded DNA into procapsids during replication. A critical step in the mechanochemical cycle of such ATPases is ATP binding, which causes a subunit within the motor to grip DNA tightly. Here, we probe the underlying molecular mechanism by which ATP binding is coupled to DNA gripping and show that a glutamate switch residue found in AAA+ enzymes is central to this coupling in viral packaging ATPases. Using free energy landscapes computed through molecular dynamics simulations, we determined the stable conformational state of the ATPase active site in apo, ATP-bound, and ADP-bound states ...


Analytic Solutions For Diffusion On Path Graphs And Its Application To The Modeling Of The Evolution Of Electrically Indiscernible Conformational States Of Lysenin, K. Summer Ware 2020 Boise State University

Analytic Solutions For Diffusion On Path Graphs And Its Application To The Modeling Of The Evolution Of Electrically Indiscernible Conformational States Of Lysenin, K. Summer Ware

Boise State University Theses and Dissertations

Memory is traditionally thought of as a biological function of the brain. In recent years, however, researchers have found that some stimuli-responsive molecules exhibit memory-like behavior manifested as history-dependent hysteresis in response to external excitations. One example is lysenin, a pore-forming toxin found naturally in the coelomic fluid of the common earthworm Eisenia fetida. When reconstituted into a bilayer lipid membrane, this unassuming toxin undergoes conformational changes in response to applied voltages. However, lysenin is able to "remember" past history by adjusting its conformational state based not only on the amplitude of the stimulus but also on its previous its ...


Interactions Of The Nlrp3 Inflammasome Complex, Nyasha Makoni 2020 University of Missouri-St. Louis

Interactions Of The Nlrp3 Inflammasome Complex, Nyasha Makoni

Dissertations

The innate immune system is the first line of defense in response to invasion by pathogens. One of the major pathways in the innate immune system involves a three-protein complex known as the NLRP3 inflammasome. This complex comprises of NLRP3, ASC, and procaspase-1. In response to stimuli, the inflammasome assembles to activate caspase-1 which subsequently facilitates production of interleukin-1β (IL-1β), an inflammatory cytokine. The NLRP3 inflammasome has been implicated in a variety of inflammatory disorders including Alzheimer’s disease (AD). Amyloid beta (Aβ) is the protein that causes AD and Aβ deposits in the brain activate microglia resulting in chronic ...


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