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Biochemistry, Biophysics, and Structural Biology

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Peroxiredoxin 6 And Inflammation In Alzheimer's Disease, Jared Ferrell-Penniman Dec 2019

Peroxiredoxin 6 And Inflammation In Alzheimer's Disease, Jared Ferrell-Penniman

Biological Sciences Theses and Dissertations

Alzheimer’s disease (AD) is known for its debilitating symptoms and poor prognosis. However, despite intense research into neurodegenerative diseases, there are few therapies targeted at the underlying mechanisms of the disease. Oxidative stress (OS) and inflammation are cellular phenomena thought to be key to the progression of the disease. Critically, peroxiredoxin 6 (Prx6), an antioxidant protein with multiple functions, has been identified from mammalian studies as a potential regulator of both OS and inflammation that may have a specific effect on AD. This project seeks to elucidate the role of Prx6 in AD as well as the underlying mechanisms ...


State-Dependent Mapping Of Glyr-Cholesterol Interactions By Coupling Crosslinking With Mass Spectrometry, Nicholas Ferraro Dec 2019

State-Dependent Mapping Of Glyr-Cholesterol Interactions By Coupling Crosslinking With Mass Spectrometry, Nicholas Ferraro

Electronic Theses and Dissertations

The glycine receptor (GlyR) belongs to a superfamily of pentameric ligand-gated ion channels (pLGICs) that mediate fast neurotransmission. GlyR typically modulates inhibitory transmission by antagonizing membrane depolarization through anion influx. Allosteric interactions between the receptor and its lipid surroundings affect receptor function, and cholesterol is essential for pLGIC activity. Human α1 GlyR was purified from baculovirus infected insect cells and reconstituted in unilamellar vesicles at cholesterol: lipid ratios below and above the cholesterol activity threshold with aliquots of azi-cholesterol. State-dependent crosslinking studies of receptors primarily in its resting (no glycine), desensitized (10mM glycine) and open (F207A/A288G, 30nM ivermectin) states ...


Modulating Mcm Levels Causes Differential Loading At Origins Of Replication And Changes Replication Timing, Livio Dukaj Dec 2019

Modulating Mcm Levels Causes Differential Loading At Origins Of Replication And Changes Replication Timing, Livio Dukaj

GSBS Dissertations and Theses

DNA replication is a highly complex part of cell metabolism that ensures safe propagation of the genome through tight regulation of the expression, localization, and activity of a large number of factors. Replication starts from distinct sites in the genome and initiation events are temporally ordered in a manner that is, on average, highly reproducible across cell populations. The specific order with which different parts of the genome are replicated has been proposed to be important to processes such as gene expression, cell differentiation, development, and genome evolution. Nevertheless, the fundamental mechanisms that are responsible for establishing these timing programs ...


Characterization Of The Nuclear Pore Complex In Red Alga, Cyanidioschyzon Merolae, Michelle Veronin Dec 2019

Characterization Of The Nuclear Pore Complex In Red Alga, Cyanidioschyzon Merolae, Michelle Veronin

Health and Kinesiology Theses

Cyanidioschyzon merolae (C. merolae) is a primitive, unicellular species of red alga that is considered to be one of the simplest self-sustaining eukaryotes. The highly elementary nature of C. merolae makes it an excellent model organism for studying evolution as well as cell function and organelle communication. In our study, we hypothesize that C. merolae contains the minimal assembly of proteins to make up their Nuclear Pore Complexes (NPCs), and hence are the first ancestral NPCs. NPCs are essential for basic nuclear transport in the cell. They are embedded in the double membrane of the nucleus, the nuclear envelope (NE ...


Rotational Tuning Of Transmembrane Helix Properties Based On The Precise Placements Of Aromatic And Charged Residues, Matthew J. Mckay Dec 2019

Rotational Tuning Of Transmembrane Helix Properties Based On The Precise Placements Of Aromatic And Charged Residues, Matthew J. Mckay

Theses and Dissertations

Designed model transmembrane peptides and oriented 2H and 15N solid-state nuclear magnetic resonance (NMR) spectroscopy were used to analyze how simple sequence modifications can influence peptide structure, behavior and dynamics as well as for determining the pKa of glutamic acid at the membrane interface. The GW5,19ALP23 (acetyl-GGALW(LA)6LWLAGA-amide) peptide framework adopts a well-defined tilted orientation in lipid bilayers (DLPC, DMPC and DOPC) and undergoes low amounts of dynamic motion. The sequence was initially modified by moving the Trp residues outwards to positions 4 and 20. This new sequence GW4,20ALP23 (acetyl-GGAW(AL)7AWAGA-amide) displays high amounts of signal ...


Investigating The Effects Of Excitotoxic Stimuli On The Suprachiasmatic Nucleus, Rachel A. Brandes Dec 2019

Investigating The Effects Of Excitotoxic Stimuli On The Suprachiasmatic Nucleus, Rachel A. Brandes

Chancellor’s Honors Program Projects

No abstract provided.


Cell Separation Delay And Membrane Trafficking Defects In Cdc42 Gap Mutants, Haylee Young Dec 2019

Cell Separation Delay And Membrane Trafficking Defects In Cdc42 Gap Mutants, Haylee Young

Chancellor’s Honors Program Projects

No abstract provided.


Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding Dec 2019

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in ...


Structure And Bioactivity Of A Rationally Designed Nicotinic Acetylcholine Receptor Antagonist Targeting The Alpha-3 Beta-2 Subtype, Leanna Marquart Dec 2019

Structure And Bioactivity Of A Rationally Designed Nicotinic Acetylcholine Receptor Antagonist Targeting The Alpha-3 Beta-2 Subtype, Leanna Marquart

Boise State University Theses and Dissertations

The work presented in this thesis contributes to ongoing development of an efficient workflow for identification of lead compounds, based on the molecular scaffold of α-conotoxin MII, for drug therapies targeting nicotinic acetylcholine receptors. Nicotinic acetylcholine receptors (nAChRs) are pentameric, ligand-gated ion channels with distribution throughout the central nervous system and are implicated in a variety of neurological diseases including schizophrenia, nicotine addiction, Alzheimer’s disease, and Parkinson’s disease. However, ligand effect on nAChR function is not well understood. Consequently, drug therapies for neurological diseases either do not exist, or have short-lasting efficacy and/or severe side effects. Barriers ...


Rna Recognition By The Glucocorticoid Receptor Dna-Binding Domain, Nicholas Victor Parsonnet Nov 2019

Rna Recognition By The Glucocorticoid Receptor Dna-Binding Domain, Nicholas Victor Parsonnet

Biochemistry Graduate Theses & Dissertations

Regulation of gene expression by transcription factors (TFs) and their co-regulatory molecules forms much of the basis of how cells interact with their environment. Long noncoding RNAs (lncRNAs) are emerging as a new class of co-regulatory factors, exploiting diverse sequence and structure motifs to interact directly with TFs. An outstanding prototype of this model is glucocorticoid receptor (GR), a TF which binds multiple RNAs in vivo and typifies the molecular decoy model—competitive binding between RNA and DNA at the TF DNA-binding domain. For example, GR binds the noncoding RNA Gas5, a tumor suppressor and growth arrest-specific RNA, via its ...


Engineering Self-Assembling Proteins To Produce A Safe And Effective Vaccine For Porcine Reproductive And Respiratory Syndrome, Ondre H. Harper Oct 2019

Engineering Self-Assembling Proteins To Produce A Safe And Effective Vaccine For Porcine Reproductive And Respiratory Syndrome, Ondre H. Harper

Electronic Thesis and Dissertation Repository

Commercially available vaccines for porcine reproductive and respiratory syndrome virus (PRRSV) provide some control over the virus but none are ideal since they either are not completely safe for use, lack efficacy in promoting long-lasting immunity or provide no protection from heterologous PRRSV strains. Innovative approaches to designing vaccines are being pursued to overcome these drawbacks. One example is the use of nanoparticles to present a dense array of antigenic epitopes to the immune system which can effectively stimulate antibody producing cells (B cells) and T cells, resulting in long-lasting immunity. Here, I genetically fused antigenic epitopes from PRRSV to ...


The Characterization Of The Rat Bone Sialoprotein Knockout Phenotype, Benjamin Harvey Oct 2019

The Characterization Of The Rat Bone Sialoprotein Knockout Phenotype, Benjamin Harvey

Electronic Thesis and Dissertation Repository

Bone sialoprotein (BSP) is an extracellular phosphoprotein that has been associated with mineralizing tissues, such as the periodontium, the fibrocartilaginous enthesis, and long bone formation. In this study, we characterized the phenotype of BSP-deficient rats. Histomorphometric analysis discovered a thinning of the acellular cementum in both 20 and 50 week-old Bsp-/- rats with no related periodontal defects and an organized periodontal ligament. Analysis of the mature quadriceps tendon (QCT) enthesis determined that BSP and osteopontin are present in the calcified fibrocartilage of wild-type rats at 14 weeks. The developing QCT enthesis of Bsp-/- rats appears similar in mineral content, collagen ...


Excess No Stabilizes The Luminal Domain Of Stim2 In A Cys-Specific Manner Thereby Regulating Basal Calcium Homeostasis And Store-Operated Calcium Entry, Matthew Novello Sep 2019

Excess No Stabilizes The Luminal Domain Of Stim2 In A Cys-Specific Manner Thereby Regulating Basal Calcium Homeostasis And Store-Operated Calcium Entry, Matthew Novello

Electronic Thesis and Dissertation Repository

Stromal-interaction molecule 2 (STIM2) is an endoplasmic reticulum (ER) membrane-inserted Ca2+-sensing protein which, together with the plasma membrane Ca2+ channel Orai1, regulates basal Ca2+ homeostasis and store-operated Ca2+ entry (SOCE). Recent evidence suggests that S-nitrosylation, which is the covalent attachment of a nitric oxide (NO) moiety to a cysteine thiol, can attenuate the function of the paralog STIM1 protein. Compared to STIM1, STIM2 also functions as a basal Ca2+ homeostatic feedback regulator. Therefore, the objective of my study was to evaluate the susceptibility of STIM2 to S-nitrosylation and the effects that this ...


Synthesis Of Crosslinkable Poly(Ester Amide)S For Cell Encapsulation And Delivery, Yu Ting (Natalie) Liang Sep 2019

Synthesis Of Crosslinkable Poly(Ester Amide)S For Cell Encapsulation And Delivery, Yu Ting (Natalie) Liang

Electronic Thesis and Dissertation Repository

Tissue engineering using adipose-derived stromal cells (ASCs) shows promise for soft tissue regeneration. Biodegradable polymers are potential biomaterials as they support the growth and delivery of cells. Specifically, poly(ester amide)s (PEAs) are a class of biodegradable polymers with tunable structures that have been shown to exhibit low cytotoxicity and support the growth of various cell types. This thesis involved the development of new water soluble amino acid-based PEAs with crosslinkable moieties to enable formation of hydrogel scaffolds for ASC encapsulation. These hydrophilic phenylalanine-based and alanine-based PEAs were synthesized by solution polycondensation and photo-crosslinked into a series of hydrogels ...


Hyaluronan At The Brain-Environment Interface, Donald M. Thevalingam Sep 2019

Hyaluronan At The Brain-Environment Interface, Donald M. Thevalingam

All Dissertations, Theses, and Capstone Projects

Hyaluronan (HA; Hyaluronic Acid), a primary scaffolding component of the brain extracellular matrix, serves as an integral structural component to the brain extracellular space (ECS). The fossorial African naked mole-rat (Heterocephalus glaber; NM-R), a mammal which lives in a low-oxygen environment and is capable of tolerating hypoxia and hypercapnia, has been shown to synthesize and sustain a unique high-molecular-mass variant of hyaluronan macromolecule (HMM-HA). This body of work highlights HA’s role in mediating the interplay between brain ECM composition, ECS structure, and cell viability.

Here we employ the NM-R as a unique animal model to observe the role of ...


Renal Specific Rnai Delivery By Fibrillar Nanoparticle Excipients, Sam Wong Sep 2019

Renal Specific Rnai Delivery By Fibrillar Nanoparticle Excipients, Sam Wong

All Dissertations, Theses, and Capstone Projects

RNA interference (RNAi) is a powerful tool to manipulate the phenotype of an organism by silencing the expression of specific genes and is viewed as a highly promising platform for treating undruggable targets and disorders where small molecule drugs and antibodies would fail. However, development of RNAi based therapies has faced major barriers including cellular and tissue-specific uptake of the Small Interfering RNA (siRNA). Utilizing different nanoparticles as RNAi excipients, cellular uptake and gene silencing potency can be greatly improved. The research in Dr. McDevitt groups has fibrillar carbon nanotubes (CNT) as carriers for siRNA for gene silencing in vitro ...


Minimalistic Peptide-Based Supramolecular Systems Relevant To The Chemical Origin Of Life, Daniela Kroiss Sep 2019

Minimalistic Peptide-Based Supramolecular Systems Relevant To The Chemical Origin Of Life, Daniela Kroiss

All Dissertations, Theses, and Capstone Projects

All forms of life are based on biopolymers, which are made up of a selection of simple building blocks, such as amino acids, nucleotides, fatty acids and sugars. Their individual properties govern their interactions, giving rise to complex supramolecular structures with highly specialized functionality, including ligand recognition, catalysis and compartmentalization. In this thesis, we aim to answer the question whether short peptides could have acted as precursors of modern proteins during prebiotic evolution. Using a combination of experimental and computational techniques, we screened a large molecular search space for peptide sequences that are capable of forming supramolecular complexes with adenosine ...


Molecular Dynamics Simulations Of Supramolecular Assemblies In Biology And Bionanotechnology, Anjela Manandhar Sep 2019

Molecular Dynamics Simulations Of Supramolecular Assemblies In Biology And Bionanotechnology, Anjela Manandhar

All Dissertations, Theses, and Capstone Projects

Molecular self-assembly is an energy driven process where randomly organized building blocks interact noncovalently to form highly organized supramolecular nanostructures. In biology, the cytoskeleton is a classic example of a dynamic self-assembly, forming long filamentous structures from monomeric protein subunits. Similarly, the self-assembly process is widely exploited in nanotechnology to build bio-functional nanostructures. In this work, we studied biological (microtubule) and synthetic (peptide drug amphiphile nanotube) self-assembled systems. We utilized long time-scale molecular dynamics simulation to investigate the structural and dynamical properties of these systems.

At the molecular level, the dynamic instability (random growth and shrinkage) of the microtubule (MT ...


Engineering Of Escherichia Coli 2-Oxoglutarate Dehydrogenase Complex With Mechanistic And Synthetic Goals, Joydeep Chakraborty Aug 2019

Engineering Of Escherichia Coli 2-Oxoglutarate Dehydrogenase Complex With Mechanistic And Synthetic Goals, Joydeep Chakraborty

Dissertations

The Escherichia coli 2-oxoglutarate dehydrogenase complex (OGDHc) compromises multiple copies of three enzymes - 2-oxoglutarate dehydrogenase (E1o), dihydrolipoyl succinyltransferase (E2o), and dihydrolipoyl dehydrogenase (E3). OGDHc is found in the Krebs cycle and catalyzes the formation of the all-important succinyl-Coenzyme A (succinyl-CoA). OGDHc was engineered to understand the catalytic mechanism and optimized for chemical synthetic goals.

Succinyl-CoA formation takes place within the catalytic domain of E2o via a transesterification reaction. The succinyl group from the thiol ester of S8-succinyldihydrolipoyl-E2o is transferred to the thiol group of CoA. Mechanistic studies were designed to investigate enzymatic transthioesterification. His375 and Asp374 was shown to be ...


Early Warning Of Global Change Effects On Catchment Nutrient Exports, Haibin Dong Aug 2019

Early Warning Of Global Change Effects On Catchment Nutrient Exports, Haibin Dong

Electronic Thesis and Dissertation Repository

Global change scientists seek sentinels of change. On forested landscapes, first-order catchments serve as sentinels of global stressors and their effects on downstream surface waters. Here, I explored global stressors – including climate warming, hydrological intensification, and recovery from atmospheric acidic deposition – and their effects on nutrient exports in 22-year stream chemistry records from 41 forested first-order catchments in a network of North American long-term monitoring sites. First, I used multivariate autoregressive models to establish relationships between changes in global stressors and changes in catchment nutrient exports. Second, I analyzed the residuals of these relationships to determine if there was evidence ...


Assessing The Structure-Function Relationships Of The Apolipoprotein(A) Kringle Iv Sub-Type 10 Domain, Matthew J. Borrelli Aug 2019

Assessing The Structure-Function Relationships Of The Apolipoprotein(A) Kringle Iv Sub-Type 10 Domain, Matthew J. Borrelli

Electronic Thesis and Dissertation Repository

Elevated plasma lipoprotein(a) (Lp(a)) is the most prevalent heritable risk factor in the development of cardiovascular disease. The apolipoprotein(a) (apo(a)) component of Lp(a) is strongly implicated in the pathogenicity of Lp(a). It is hypothesized that the inflammatory potential of Lp(a)/apo(a) is mediated by the lysine binding ability of the apo(a) kringle IV10 (KIV10) domain, along with its covalently bound oxidized phospholipid (oxPL). Using targeted mutagenesis, two novel null alleles for the LPA gene that generate non-secretable apo(a) species have been identified, resulting from amino acid substitutions in the KIV10 ...


Monocyte Mri Relaxation Rates Are Regulated By Extracellular Iron And Hepcidin, Praveen S.B Dassanayake Aug 2019

Monocyte Mri Relaxation Rates Are Regulated By Extracellular Iron And Hepcidin, Praveen S.B Dassanayake

Electronic Thesis and Dissertation Repository

Monocytes are an important immune cell type in chronic inflammatory conditions like atherosclerosis and heart failure. The increase in number of monocytes released to the peripheral blood circulation, the differentiation of monocytes to macrophages, and the presence of different macrophage subpopulations during pro- and anti-inflammatory stages of tissue injury may provide markers for monitoring inflammation. In particular, changes in monocyte iron metabolism during an inflammatory response may increase the possibility of tracking these immune cells non-invasively using magnetic resonance imaging (MRI). When secretion of the polypeptide hormone hepcidin is stimulated during inflammation, it binds the iron export protein ferroportin (FPN ...


Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin Aug 2019

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

Engineering and Applied Science Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge ...


Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen Aug 2019

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

Engineering and Applied Science Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency.

Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA ...


Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen Aug 2019

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

Engineering and Applied Science Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency. Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA ...


Mechanism Of Activation Of Uvrd Helicase By A Processivity Factor Mutl, Yerdos Ordabayev Aug 2019

Mechanism Of Activation Of Uvrd Helicase By A Processivity Factor Mutl, Yerdos Ordabayev

Arts & Sciences Electronic Theses and Dissertations

E. coli UvrD is a superfamily 1A helicase/translocase involved in DNA repair, recombination, and replication. I investigated the role of E. coli MutL, a regulatory protein involved in methyl-directed mismatch DNA repair, in the regulation of UvrD-catalyzed DNA unwinding. Using single molecule fluorescence resonance energy transfer (FRET) and single round stopped-flow DNA unwinding experiments I demonstrated that MutL can activate latent UvrD monomer helicase activity and also stimulate UvrD dimer helicase activity. Furthermore, using analytical ultracentrifugation experiments I determined that a single MutL dimer is sufficient to activate UvrD monomer helicase. DNA unwinding experiments with a series of DNA ...


Mechanism Of Activation Of Uvrd Helicase By A Processivity Factor Mutl, Yerdos Ordabayev Aug 2019

Mechanism Of Activation Of Uvrd Helicase By A Processivity Factor Mutl, Yerdos Ordabayev

Arts & Sciences Electronic Theses and Dissertations

E. coli UvrD is a superfamily 1A helicase/translocase involved in DNA repair, recombination, and replication. I investigated the role of E. coli MutL, a regulatory protein involved in methyl-directed mismatch DNA repair, in the regulation of UvrD-catalyzed DNA unwinding. Using single molecule fluorescence resonance energy transfer (FRET) and single round stopped-flow DNA unwinding experiments I demonstrated that MutL can activate latent UvrD monomer helicase activity and also stimulate UvrD dimer helicase activity. Furthermore, using analytical ultracentrifugation experiments I determined that a single MutL dimer is sufficient to activate UvrD monomer helicase. DNA unwinding experiments with a series of DNA ...


A Physics-Based Intermolecular Potential For Biomolecular Simulation, Joshua Andrew Rackers Aug 2019

A Physics-Based Intermolecular Potential For Biomolecular Simulation, Joshua Andrew Rackers

Arts & Sciences Electronic Theses and Dissertations

The grand challenge of biophysics is to use the fundamental laws of physics to predict how biological molecules will move and interact. The atomistic HIPPO (Hydrogen-like Intermolecular Polarizable Potential) force field is meant to address this challenge. It does so by breaking down the intermolecular potential energy function of biomolecular interactions into physically meaningful components (electrostatics, polarization, dispersion, and exchangerepulsion) and using this function to drive molecular dynamics simulations. This force field is able to achieve accuracy within 1 kcal/mol for each component when compared with ab initio Symmetry Adapted Perturbation Theory calculations. HIPPO is capable of this accuracy ...


Electron Decoupling With Chirped Microwave Pulses For Magic Angle Spinning Dynamic Nuclear Polarization Nuclear Magnetic Resonance Spectroscopy, Edward Paul Saliba Aug 2019

Electron Decoupling With Chirped Microwave Pulses For Magic Angle Spinning Dynamic Nuclear Polarization Nuclear Magnetic Resonance Spectroscopy, Edward Paul Saliba

Arts & Sciences Electronic Theses and Dissertations

Dynamic nuclear polarization (DNP) is a method of generating hyperpolarization of nuclear spins for nuclear magnetic resonance (NMR) spectroscopy. Coherent, time domain techniques make the possibility of DNP directly to spins of interest at room temperature and higher feasible in magic angle spinning (MAS) NMR, allowing for optimal experimental repetition times to be limited by the T_1 of the electron, rather than a much longer T_1DNP, with excellent resolution. The strong hyperfine couplings that make such direct DNP transfers possible, however, can lead to short nuclear relaxation times that result in broadening of nuclear resonances and reduce sensitivity. This dissertation ...


Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin Aug 2019

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

Engineering and Applied Science Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge ...