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Full-Text Articles in Engineering

Scale Up Of A Novel Method To Maximize Malonyl-Coa In Escherichia Coli, Clifford Harris Leblanc Iv Jul 2022

Scale Up Of A Novel Method To Maximize Malonyl-Coa In Escherichia Coli, Clifford Harris Leblanc Iv

LSU Master's Theses

The instability of oil’s price along with its limited availability and impact on the environment motivate the search for an alternative feedstock that can sustain the profitability of chemical companies. Industrial biotechnology can promote renewable sources of energy and products by using microorganisms to produce a wide range of chemical compounds. The three-carbon metabolite, malonyl-CoA, can serve as a precursor to a variety of industrial chemicals. The major hurdle with using malonyl-CoA in industry is that its intracellular concentration in Escherichia Coli is very low. Previous attempts to increase the intracellular level of malonyl-CoA have ranged from genetic engineering of …


Model-Guided Design Of Rna-Based Synthetic Circuits For The Dynamic Regulation Of Gene Expression, Jordan R. Ryan Apr 2022

Model-Guided Design Of Rna-Based Synthetic Circuits For The Dynamic Regulation Of Gene Expression, Jordan R. Ryan

LSU Master's Theses

A longstanding goal in synthetic biology has been to build synthetic gene circuits with the ability to harness nature’s capability of precise gene expression regulation. Advancements in RNA technology have established RNA-based regulators with distinct advantages over traditional protein-based regulators such as faster signal propagation, versatile programmability, and low cellular burden, which has created an interest in the field to construct innovative synthetic gene circuits using de novo RNA- based regulators. However, our understanding of the behavior and kinetics of RNA-RNA interactions for the construction of gene circuits is incomplete. This thesis proposes a model-guided design framework that integrates mechanistic …


Tuning Electrochemical Interactions And Polymer Electrolyte Interfaces For Enhanced Organic Acid Separations Using Electrodeionization, Matthew Leo Jordan Mar 2022

Tuning Electrochemical Interactions And Polymer Electrolyte Interfaces For Enhanced Organic Acid Separations Using Electrodeionization, Matthew Leo Jordan

LSU Doctoral Dissertations

Chemical separations are critical processes for chemical and industrial plants to purify and isolate products however current separation technologies, such as distillation, rely on energy intensive processes. Electrochemical separation processes, such as electrodialysis and electrodeionization, are an energy efficient alternative that are emerging as an alternative for thermal-based separations. Organic acids are weakly ionizable species and susceptible for purification from process streams using electrochemical processes. Recently the fermentation route has garnered greater attention as a means for producing value-added chemicals, such as organic acids, from a renewable feedstock and aiding the circular economy. Some of the challenges electrodialysis faces for …


Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed Jul 2021

Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed

LSU Master's Theses

Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …


Photoluminescent Nanomaterials For Biosensing And Single Cell Analysis Applications, Khashayar Ramezani Bajgiran Mar 2021

Photoluminescent Nanomaterials For Biosensing And Single Cell Analysis Applications, Khashayar Ramezani Bajgiran

LSU Doctoral Dissertations

The bioanalytical industry is projected to generate $36 billion by 2025, with the United States currently holding 80.9% of the consumers’ market. Among the bioanalytical platforms, point-of-care (POC) and point-of-use diagnosis (POU) have gained a lot of attention due to their emphasis on decentralized testing and providing low-cost solutions in resource-limited regions. While Traditional bioanalytical tools such as enzyme-linked immunosorbent assay and flow cytometry can sensitively detect biomolecules and screen single-cell response, they suffer from multiple drawbacks such as the high cost of antibodies and time-intensive procedures, which limit their ability to expand to POC/POU applications. Rapid developments in microtool …


A Microscale Approach To Investigate Breast Cancer Cellular Communication And Migration, Sharif Mohammad Mizanur Rahman Jan 2021

A Microscale Approach To Investigate Breast Cancer Cellular Communication And Migration, Sharif Mohammad Mizanur Rahman

LSU Doctoral Dissertations

Metastatic breast cancer significantly decreases patient survival, with the majority of deaths caused by secondary metastasis. Cancer metastasis is a multi-step process that starts with the detachment of a cancer cell from the primary tumor and ends with establishing a secondary tumor at a distal location. This work's focus was to use an interdisciplinary microscale approach to study how cancer cells respond to neighboring cells and how they migrate in response to chemical gradients. Two distinct devices, a microfluidic device, and a 3D-printed plate insert, were developed to perform co-culture studies to elucidate the impact of ASCs on cancer cell …


Incorporation Of Lignin In Natural And Synthetic Biomaterials To Alter Mechanical And Biochemical Properties For Enhanced Wound Healing, Jorge Alfonso Belgodere Nov 2020

Incorporation Of Lignin In Natural And Synthetic Biomaterials To Alter Mechanical And Biochemical Properties For Enhanced Wound Healing, Jorge Alfonso Belgodere

LSU Doctoral Dissertations

It is estimated that chronic, non-healing wounds affect more than 6.5 million Americans annually, with an estimated healthcare cost beyond $14 billion. Here, we attempted to create composites of natural (collagen type I or gelatin-methacrylate) or synthetic (poly(ethylene glycol) polymers incorporating a natural plant component, lignin, to combat the costs and limitations current wound healing methods face. Three-dimensional matrices of collagen type I (Col I) are widely used in tissue engineering applications for its abundance in many tissues, bioactivity with many cell types, and excellent biocompatibility. Inspired by the structural role of lignin in plant tissue, we found that sodium …


Metabolic Network Analysis Of Filamentous Cyanobacteria, Daniel Alexis Norena-Caro Jun 2020

Metabolic Network Analysis Of Filamentous Cyanobacteria, Daniel Alexis Norena-Caro

LSU Doctoral Dissertations

Cyanobacteria were the first organisms to use oxygenic photosynthesis, converting CO2 into useful organic chemicals. However, the chemical industry has historically relied on fossil raw materials to produce organic precursors, which has contributed to global warming. Thus, cyanobacteria have emerged as sustainable stakeholders for biotechnological production. The filamentous cyanobacterium Anabaena sp. UTEX 2576 can metabolize multiple sources of Nitrogen and was studied as a platform for biotechnological production of high-value chemicals (i.e., pigments, antioxidants, vitamins and secondary metabolites). From a Chemical engineering perspective, the biomass generation in this organism was thoroughly studied by interpreting the cell as a microbial …


Experimental And Computational Tools For Single Cell Analysis In Cancer Diagnostics, Manibarathi Vaithiyanathan Jan 2020

Experimental And Computational Tools For Single Cell Analysis In Cancer Diagnostics, Manibarathi Vaithiyanathan

LSU Doctoral Dissertations

Substantial evidence shows that cellular heterogeneity commonly exists within an isogenic or clonal population. Whether in isolation or caused through a combination of the above events, cellular heterogeneity can dramatically influence cellular decision making and cell fate, however, this can be masked by the average response from a population. One approach to solve this issue is to analyze a population at the individual cell level. The goal of this work is to develop high-throughput experimental and computational platforms to screen and quantify single cancer cells for specific intracellular enzyme activities. An interdisciplinary approach was taken to 1) better understand the …


Maximizing And Modeling Malonyl-Coa Production In Escherichia Coli, Tatiana Thompson Silveira Mello Jun 2019

Maximizing And Modeling Malonyl-Coa Production In Escherichia Coli, Tatiana Thompson Silveira Mello

LSU Master's Theses

In E. coli, fatty acid synthesis is catalyzed by the enzyme acetyl-CoA carboxylase (ACC), which converts acetyl-CoA into malonyl-CoA. Malonyl-CoA is a major building block for numerous of bioproducts. Multiple parameters regulate the homeostatic cellular concentration of malonyl-CoA, keeping it at a very low level. Understanding how these parameters affect the bacterial production of malonyl-CoA is fundamental to maximizing it and its bioproducts. To this end, competing pathways consuming malonyl-CoA can be eliminated, and optimal nutritional and environmental conditions can be provided to the fermentation broth. Most previous studies utilized genetic modifications, expensive consumables, and high-cost quantification methods, making …


Direct Quantification Of Deubiquitinating Enzyme Activity In Single Intact Cells, Nora Safabakhsh Aug 2018

Direct Quantification Of Deubiquitinating Enzyme Activity In Single Intact Cells, Nora Safabakhsh

LSU Doctoral Dissertations

Challenges in drug efficacy occur during the treatment of most types of cancer due to the heterogeneity of the tumor microenvironment. This has led to the development of personalized medicine. Due to the clinical success of the proteasome inhibitors Bortezomib and Carfilzomib in treatment of multiple myeloma, interest has shifted towards molecularly-targeted chemotherapeutics for ubiquitin-proteasome system (UPS). Deubiquitinating enzymes (DUBs) are an essential part of this pathway which have been found to promote Bortezomib resistance in multiple myeloma patients. Unfortunately, there is a lack of specific, high throughput biochemical assays to characterize DUB activity in patient samples before and after …


High-Throughput Droplet Barcoding And Automated Image Analysis In Microfluidic Droplet Trapping Array, Manibarathi Vaithiyanathan Nov 2017

High-Throughput Droplet Barcoding And Automated Image Analysis In Microfluidic Droplet Trapping Array, Manibarathi Vaithiyanathan

LSU Master's Theses

Molecularly-targeted therapeutics and personalized medicine have dramatically increased the median survival rate of patients suffering from cancer. However, cellular heterogeneity and the personalized nature of cancer have resulted in the limited success of single drug treatments which has led to the use of multiple therapeutic combinations. This has required the development of new analytical methods capable of multiplexed high-throughput screening (HTS) technologies necessary to identify is single or multi-agent therapies are effective in ex vivo samples like liquid biopsies. Droplet microfluidic devices have garnered significant interest to facilitate high-throughput, single cell analysis of heterogeneous populations. However, these devices are still …