Biochemistry, Biophysics, and Structural Biology Commons^™

Surface And Structural Modification Of Carbon Electrodes For Electroanalysis And Electrochemical Conversion, Yan Zhang

Theses and Dissertations--Chemistry

Electrocatalysis is key to both sensitive electrochemical sensing and efficient electrochemical energy conversion. Despite high catalytic activity, traditional metal catalysts have poor stability, low selectivity, and high cost. Metal-free, carbon-based materials are emerging as alternatives to metal-based catalysts because of their attractive features including natural abundance, environmental friendliness, high electrical conductivity, and large surface area. Altering surface functionalities and heteroatom doping are effective ways to promote catalytic performance of carbon-based catalysts. The first chapter of this dissertation focuses on developing electrode modification methods for electrochemical sensing of biomolecules. After electrochemical pretreatment, glassy carbon demonstrates impressive figures-of-merit in detecting small, redox-active …

Protein Suppression Of Flavin Semiquinone As A Mechanistically Important Control Of Reactivity: A Study Comparing Flavoenzymes Which Differ In Redox Properties, Substrates, And Ability To Bifurcate Electrons, John Patrick Hoben

Theses and Dissertations--Chemistry

A growing number of flavoprotein systems have been observed to bifurcate pairs of electrons. Flavin-based electron bifurcation (FBEB) results in products with greater reducing power than that of the reactants with less reducing power. Highly reducing electrons at low reduction midpoint potential are required for life processes of both aerobic and anaerobic metabolic processes. For electron bifurcation to function, the semiquinone (SQ) redox intermediate needs to be destabilized in the protein to suppress its ability to trap electrons. This dissertation examines SQ suppression across a number of flavin systems for the purpose of better understanding the nature of SQ suppression …

Protein Engineering In The Study Of Protein Labeling And Degradation, Xinyi Zhang

Theses and Dissertations--Chemistry

Proteins are large macromolecules that play important roles in nature. With the development of modern molecular biology techniques, protein engineering has emerged as a useful tool and found many applications in areas ranging from food industry, environmental protection, to medical and life science. Biomimetic membrane incorporates biological elements, such as proteins, to form membranes that mimic the high specificity and conductance of natural biological membranes. For any application involving the usage of proteins, the first barrier is always the production of proteins with sufficient stability, and the incorporation of proteins into the artificial matrix. This thesis contains two major parts, …

Study Of The Mechanism Of Action For Ru(Ii) Polypyridyl Complexes As Potential Anticancer Agents, Yang Sun

Theses and Dissertations--Chemistry

Application of chemotherapeutic agents in current cancer treatment has been limited by adverse effects as poor selectivity results in systemic toxicity; most chemotherapy approaches also experience inherited or acquired drug resistance which lead to reduced treatment outcome. Research efforts have focused on the discovery of novel chemotherapies that overcome the limitations mentioned above. Ru(II) polypyridyl complexes with anti-cancer properties have been extensively studied as traditional cytotoxic agents and photodynamic therapy agents due to their photophysical and photochemical characteristics.

Most research has focused on the design of Ru(II) polypyridyl complexes that have affinities to nucleic acids as inspired by the classic …

Applications Of Cell-Derived Vesicles: From Single Molecule Studies To Drug Delivery, Faruk H. Moonschi

Theses and Dissertations--Chemistry

Single molecule studies can provide information of biological molecules which otherwise is lost in ensemble studies. A wide variety of fluorescence-based techniques are utilized for single molecule studies. While these tools have been widely applied for imaging soluble proteins, single molecule studies of transmembrane proteins are much more complicated. A primary reason for this is that, unlike membrane proteins, soluble proteins can be easily isolated from the cellular environment. One approach to isolate membrane proteins into single molecule level involves a very low label expression of the protein in cells. However, cells generate background fluorescence leading to a very low …

Assembly And Trafficking Of The Cystic Fibrosis Transmembrane Conductance Regulator And Associated Proteins, Zhihui Zhang

Theses and Dissertations--Chemistry

Cystic Fibrosis (CF) is an autosomal recessive genetic disease that leads to severe malfunction in many organs, but particularly the lungs. The primary cause of this malfunction is the decrease of the airway surface liquid layer on the lung epithelium. The lack of hydration leads to mucus build up on the epithelial lining, leading to blockage of airways. The underlying cause of CF is the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR), which results from mutations in the protein. Almost 90% of CF patients are caused by the deletion of the phenylalanine at position 508 of CFTR, which …