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Analytical Chemistry

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Theses/Dissertations

2011

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Articles 31 - 60 of 64

Full-Text Articles in Physical Sciences and Mathematics

Nanoencapsulated Drug-Carrying System For Photodynamic Antimicrobial Chemotherapy (Pact), Gopala Krishna Murthy Kalapala Jul 2011

Nanoencapsulated Drug-Carrying System For Photodynamic Antimicrobial Chemotherapy (Pact), Gopala Krishna Murthy Kalapala

All Capstone Projects

The purpose of this study is to develop nanoparticulate drug-carrying systems that are capable of directly delivering photodynamic antimicrobial agents to treat patients with chronic wounds. Chronic wounds are considered as a pandemic health problem. Approximately 1% to 2% of the population in developing countries has experienced a chronic wound during their lifetime. In the United State States, according to the American Academy of Dermatology, the expense of treating chronic wounds constitutes over half of the total cost for all skin diseases, which exceeds $10 billion annually. For the last decade extensive basic science and clinical research in chronic wounds …


Micro Bca Analysis Of Proteins, Anusha Chennupati Jul 2011

Micro Bca Analysis Of Proteins, Anusha Chennupati

All Capstone Projects

The main objective of this project was to develop and validate methods for detection and analysis of proteins using a newly introduced microdrop plate reader equipped with a 16 well microdrop reader (2 uL sample volume). We used commercially available BSA, egg albumin, trypsinogen, Pepsin, β-lactoblobulin and lysozyme as out test moieties. Protein drop size, time, BCA reagent quantity, was assessed at various levels using a microdrop micro-BCA protocol (Pierce Chemical Company) with the appropriate controls (PBS blank) the method validated using the appropriate statistical and method parameters (i.e %RSD, and regression analysis of the standard curves). The micro method …


Analysis Of Anions In Water Samples From The Holy Land (Israel And Jordan) By Using Ion Chromatography, Ahalya Yalamanchili Jul 2011

Analysis Of Anions In Water Samples From The Holy Land (Israel And Jordan) By Using Ion Chromatography, Ahalya Yalamanchili

All Capstone Projects

Ion chromatography is a form of liquid chromatography, which measures concentration of ionic species by separating them based on their interaction with resins. Ion chromatography is mainly useful for the separation and analysis of ions (cations or anions) in water. Analysis of anions in water is of greater importance because water is very important in daily life, especially in the Holy Land, where water is the very essence of life. If variety of chemicals, such as organic and inorganic salts enter into the water system, they make water toxic and poisonous to drink. In this project water samples from different …


The Nature, Origin And Preservation Of Amide Organic Nitrogen In Organic Matter, Georgina Anne Mckee Jul 2011

The Nature, Origin And Preservation Of Amide Organic Nitrogen In Organic Matter, Georgina Anne Mckee

Chemistry & Biochemistry Theses & Dissertations

Past studies have found much of nonliving sedimentary/aqueous nitrogen-containing organic matter (NCOM) is composed of amides, assumed to be peptides/proteins. Their lability calls into question their survival, and several hypotheses have been suggested to explain this. Using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and nuclear magnetic resonance (NMR) spectroscopy I investigated the molecular amide composition in sedimentary/aqueous systems while reassessing their preservation and formation routes.

Development of a suitable methodology is essential for successful NCOM study due to electrospray ionisation source requirements: sediment samples need to be rendered into solution. Based on NMR and FT-ICR-MS analysis, I determined …


Development Of Two-Dimensional Gel Electrophoresis Procedures For Analysis Of Cupriavidus Necator H16 Subcellular Proteomes, Smita Joshi Jun 2011

Development Of Two-Dimensional Gel Electrophoresis Procedures For Analysis Of Cupriavidus Necator H16 Subcellular Proteomes, Smita Joshi

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Smita Joshi on June 17, 2011.


The Elucidation Of Stationary Phase Treatment Effects In Enantiomeric Separations, Joel Garrett Putnam May 2011

The Elucidation Of Stationary Phase Treatment Effects In Enantiomeric Separations, Joel Garrett Putnam

Doctoral Dissertations

Acid/base modifiers are sometimes used as additives in the elution on columns packed with amylose tris(3,5-dimethylphenylcarbamate) stationary phase to separate enantiomers. When modifiers are removed from the mobile phase, the stationary phase is affected in ways that are not understood because of the lack of systematic studies, making the scale-up of preparative separations difficult to predict. Once a column has been exposed to these modifiers, the selectivity of certain pairs of enantiomers may change, for the better or the worse. Numerous pairs of molecules affected by this phenomenon are listed in the literature. Five pairs of these molecules were chosen, …


Thermally Robust Ald And Silver Nanocube Based Plasmonic Probe For High Temperature And Microfluidic Sers Measurement, Joshy Francis John May 2011

Thermally Robust Ald And Silver Nanocube Based Plasmonic Probe For High Temperature And Microfluidic Sers Measurement, Joshy Francis John

Doctoral Dissertations

Raman spectroscopy is normally a non-destructive, highly selective technique that has become an ubiquitous tool for analytical chemists. One of the primary limitations of Raman spectroscopy, however, is the relatively low cross-section of the technique. With signal enhancements relative to normal Raman scattering as high as 1011, the ultra-trace detection of adsorbates down to the single molecule level has been achieved with SERS. Despite the dramatic improvement in the sensitivity and the high selectivity afforded by the SERS method, the acceptance of SERS as a general analytical tool has been hindered by a lack of stability and reproducibility in the …


Surface-Enhanced Raman Scattering: Substrate Development And Applications In Analytical Detection, Deepak Bhandari May 2011

Surface-Enhanced Raman Scattering: Substrate Development And Applications In Analytical Detection, Deepak Bhandari

Doctoral Dissertations

To advance the capabilities of surface-enhanced Raman scattering (SERS), we developed a silver modified polypropylene filter (AgPPF) substrate which acts as a pseudo stationary phase in harvesting SERS signatures of so called "phytochemical estrogens" and other environmentally significant chemicals. To augment electron beam lithography (EBL) in SERS research, we also introduced an interesting nanotransfer printing (nTP) technique which could circumvent the low throughput and extremely high resolution (< 10 nm) limitations of EBL in designing advanced SERS substrates. In our study, a nominal average thickness of 10 nm silver on the polypropylene microfiber produced nanoglobules of less than 100 nm in diameter. This noble metal nanoroughened layer allowed AgPPF to serve as a SERS active substrate, onto which the noted endocrine disrupting chemicals were passed through and harvested. The intense, multifeatured vibrational Raman spectra of very rarely SERS studied chemical species collected indicates the potential for useful detection via this approach of creating SERS substrates. AgPPF substrates were also used in characterizing the adsorption behavior of hydroxyl complexes of uranium. Interestingly, hydroxyl group on the uranium complexes showed slow sorption kinetics on the nanostructured silver surfaces. Understanding the adsorption behavior of aqueous solution of uranium on nanostructured silver surfaces has opened up the possibilities of SERS detection of these environmental and non-proliferation concerned species without any surface modifications. nTP is a high resolution printing technique and relies on interfacial chemistries to control the transfer of thin metal film from a "stamp" to a "substrate". In our research, high-aspect-ratio AutoCAD designed nanopatterns were created on silicon wafers using e-beam lithography and reactive ion etching. Silicon relief pillars based stamps were then used to integrate a variety of nanostructures on different dielectric materials. Thus created nanopatterns have shown their promise to hold their inherent SERS activity. For its simplicity, cost-effectiveness, and ease of operation, this hyphenated nTP-SERS technique is impressive in the selection of suitable supporting-films for better SERS enhancements and also to manipulate gap between nanodiscs (gap-plasmonic SERS effect).


Adsorbents With Chemically Bonded Saccharide Surfaces: Synthesis And Application For Stereoisomer Separation And The Synthesis Of Chiral Porous Silicas Using Templates Chiral Surfactant, Edwin Vega May 2011

Adsorbents With Chemically Bonded Saccharide Surfaces: Synthesis And Application For Stereoisomer Separation And The Synthesis Of Chiral Porous Silicas Using Templates Chiral Surfactant, Edwin Vega

Seton Hall University Dissertations and Theses (ETDs)

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Extraction Chromatographic Studies Of Rutherfordium And Dubnium Homologs, Megan E. Bennett May 2011

Extraction Chromatographic Studies Of Rutherfordium And Dubnium Homologs, Megan E. Bennett

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studying the chemistry of transactinide elements does not only allow for these elements to be properly placed in the Periodic Table, but it also permits for the extrapolation of the electronic structure based upon the position of the element in the Periodic Table. In addition it enable for the assessment of the role that relativistic effects play in the chemical behavior of the heaviest elements. An improved understanding of the role of relativistic effects in chemistry of the heaviest elements allows for a better understanding of the fundamentals principles that govern the Periodic Table. In order to investigate the chemistry …


Synthesis And Analytical Evaluation Of Folate Conjugates For Use In Cancer Cell Detection, Pradipkumar Koshiya Apr 2011

Synthesis And Analytical Evaluation Of Folate Conjugates For Use In Cancer Cell Detection, Pradipkumar Koshiya

All Capstone Projects

Folate-targeted dyes have been used for the detection of tumor tissue and isolated cancer cells in both the animal tumor models as well as in human cancer patients. Folate receptors (FR) are abundantly present on several cancerous cell types but they are found less in normal human cells. There are several imaging agents that can be linked with folic acid and used for the detection of tumor. These imaging agents could be protein toxins, chemotherapeutic agents, gene therapy vectors, oligonucleotides, radioimaging agents, magnetic resonance imaging contrast agents and liposomes with entrapped drugs, radiotherapeutic agents and/or immunotherapeutic agents. This research showed …


Detection Of Protein By Microdrop Analysis, Yogeshkumar Radadiya Apr 2011

Detection Of Protein By Microdrop Analysis, Yogeshkumar Radadiya

All Capstone Projects

Analysis of protein depends particularly on protein concentration. Protein concentration measurement is the most important part in the research work to conduct protein-related studies. Although there are many methods available for this purpose, each method has certain limitations. The aim of the experiment is to develop either new or modified analytical method for the analysis and detection of protein using newly introduced micro-plate reader equipped with Take-3 microplate with the help of Gen-5 software. An ideal assay should be simple and easy to carry out. Another aspect to be taken into consideration are low inference, stability of measured components and …


Detection Of Folate Binding Protein, Anwer Unnisa Apr 2011

Detection Of Folate Binding Protein, Anwer Unnisa

All Capstone Projects

Cancer is the second leading cause of death despite the anti cancer developments including hormone therapy, radiotherapy, chemotherapy. Chemotherapy includes use of potent drugs such as camptothecin, paclitaxel and mitomycin. These drugs have an effect which is dose responsive, where the drug exposure and cell kill are proportional. This chemotherapy is high dose and has less selectivity for cancer cells and has more toxic effect to normal cells. Such kind of non specific treatment to tumor is causing hurdles in the treatment of cancer by chemotherapy. To overcome this current limitation to chemotherapy, the anti cancer drug with high specificity …


Improved Analytical Analysis Of A Pressurized Water Reactor Secondary Loop, Megan J. Holba Apr 2011

Improved Analytical Analysis Of A Pressurized Water Reactor Secondary Loop, Megan J. Holba

All Capstone Projects

In the nuclear industry, the addition of poly-acrylic acid (PAA) as a dispersant to the secondary cooling loop in pressurized water reactors (PWRs) has been found beneficial in keeping the corroded Fe in solution. The purpose of this study is to measure the effectiveness of the addition of PAA to Braidwood Nuclear Power Station and other plants, to show the benefits of PAA implementation and to evaluate the current method for Fe detection. The current analytical method for the X-Ray Fluorescence Detector has an upper detection limit of 5,000 μg Fe, however, the results frequently exceed the upper limit. In …


Determination Of 237np In Bioassay Fecal Samples, Bettylou M. Wahl Apr 2011

Determination Of 237np In Bioassay Fecal Samples, Bettylou M. Wahl

All Capstone Projects

237Np, a long-lived alpha-emitting actinide, is present in the environment due to releases from atmospheric nuclear weapons tests, reactor accidents, and nuclear reprocessing plants. The determination of long-lived actinides, such as neptunium, is essential for worker monitoring and environmental control. In bioassay and environmental samples, a radiochemical separation is necessary before measurement in order to eliminate any inferences that may occur in a mixture of actinides. In this paper, a method for determining 237Np in fecal samples using TEVA resin is investigated. Using 239Pu as a tracer, tetravalent plutonium and neptunium were successfully separated from other actinides. …


Developing Novel Nanoparticulated Imaging System Using Luminescence Enhancement Of Eu(Iii) And Tb(Iii) By Single-Strand Dna Encapsulation, David A. Corcoran, Diana L. Harms (Galindo) Apr 2011

Developing Novel Nanoparticulated Imaging System Using Luminescence Enhancement Of Eu(Iii) And Tb(Iii) By Single-Strand Dna Encapsulation, David A. Corcoran, Diana L. Harms (Galindo)

All Student Theses

Non-toxic biosensors are encountering an increase in attention for use in understanding the fate of cells and as a diagnostic tool. Development and incorporation of suitable fluorophores into biological molecules is the key for monitoring proteins in vivo research. This study investigated the enhanced emission of Eu (III) and Tb (III) upon binding to the four DNA bases and their respective nucleotides, found the best ratio for effective energy transfer, and developing nanoparticles to deliver the biosensor into the cells.

It is well known that Eu (III) and Tb (III) exhibit very distinctive photo-characteristics. The luminescence of these two lanthanides …


Synthesis And Characterization Of Nanoparticulated Rifampicin, Lakshmi Sai Priyanka Guttikonda Apr 2011

Synthesis And Characterization Of Nanoparticulated Rifampicin, Lakshmi Sai Priyanka Guttikonda

All Capstone Projects

Rifampicin is a naturally made, non-peptide antibiotic. It is bactericidal, killing by disabling the protein expression system universally conserved by all bacteria. Specifically, it inhibits the RNA polymerase protein, which is responsible for binding to a strand of DNA as a template and using it to construct a strand of mRNA. The reason rifampicin works so well is that it is a rigid molecule, and sits tightly in the pocket where it binds, allowing the bonds to be very strong. However, this also means if an amino acid with the edge of the channel with a small side chain is …


Synthesis And Analytical Evaluation Of Folate Conjugates For Use In Cancer Cell Detection, Rakeshkumar V. Desai Apr 2011

Synthesis And Analytical Evaluation Of Folate Conjugates For Use In Cancer Cell Detection, Rakeshkumar V. Desai

All Capstone Projects

Folate receptors have two glycosyl phosphatidylinositol anchored isomers, alpha and beta. Folate receptor alpha binds with high affinity for folic acid and act as a receptor for mediated transport of folate into the cells. Folate is necessary for DNA metabolism and thus it is speculated that rapidly dividing cancer cells have an increased necessity for folic acid. Folate receptor alpha levels eminent in specific malignant diseases (like solid tumors and leukemia) and thus folate receptors serve in the detection of FR+ (Folate receptor positive) and diagnosis of cancers.

In general, liposomes have the capacity intake the most imaging and toxic …


Purification And Analysis Of Folate Dye Conjugates, Anisha Hari Ganji Apr 2011

Purification And Analysis Of Folate Dye Conjugates, Anisha Hari Ganji

All Capstone Projects

Folate receptors play an important role in drug delivery systems as they are known to increase the potency and reduce toxicity of many cancer therapies. Folate receptors are present in abundance on cancerous tissues more so than on non-cancerous tissues. Folate binds to a variety of drugs that include chemotherapeutic agents, liposomes, radio-imaging agents, immunotherapeutic drugs and the like. Folate has been researched and used over the past decade as it is inexpensive and binds to the folate receptors with high affinity when compared to monoclonal antibodies. Nuclear imaging by SPECT and PET has interested many researchers. Other processes include …


Determination Of Protein Using Microdrop Assay, Hardik Khared Apr 2011

Determination Of Protein Using Microdrop Assay, Hardik Khared

All Capstone Projects

After purification of protein, it is important to know the concentration of protein in our samples. Concentration or amount of protein in the sample is determined by different assay as BCA (bicinchoninic acid) Assay, Bradford Assay, and Lowery Assay. There are different methods available to perform these assays, which have some limitations, restrictions, advantages and disadvantages. These methods require large amounts of costly reagents, proteins and most importantly, valuable time. To overcome these problems a new method is developed called Microdrop Protein Analysis. This new method required a very small amount of reagents and protein mixtures (2-5 µʅ volume) and …


Detection Of Folate Receptor From Fr+ Cancer Cells, Darpan Patel Apr 2011

Detection Of Folate Receptor From Fr+ Cancer Cells, Darpan Patel

All Capstone Projects

The aim was to detect cancer cells by using folate–PEG-Biotin probe with fluorescently labeled streptavidin for targeted drug delivery of anti-cancer drugs and diagnose cancer cells. Folate-PEG-Biotin (synthesized by Dr. Henne and Mr.Rohan Patel) was purified by HighPeformanceLiquidChromatography (HPLC) analysis and with the help of Liquid Chromatography/Mass Spectrometry (LC/MS) its identity was confirmed. Folate is a basic composition of cell metabolism in both synthesis of DNA and proteins. Growing cancer cells require high level of folic acid. Folate Receptor-α (FR-α) is a membrane bound protein having high affinity for folic acid and serves to transport of folate into cells. Poly …


Evaluation And In Vitro Studies Of Folate-Peg-Biotin, Kuldeep Reddy Vanga Apr 2011

Evaluation And In Vitro Studies Of Folate-Peg-Biotin, Kuldeep Reddy Vanga

All Capstone Projects

Folate receptor is a membrane bound protein which is highly expressed by cancer cells and macrophages. Folic acid is required for the normal growth of cells and it has been found that rapidly growing cancer cells require high levels of folic acid. Folic acid binds to folate receptors and through receptor mediated transport folate enters cells. This property has been used to synthesize a probe using folate as ligand through polyethylene glycol-Biotin linker. This can be used to attach a drug which is ultimately delivered at the site of infectious cells. The study involved here was to determine how folate …


Electrochemical Studies Of Quinone On Clay-Modified Platinum Electrodes, Thomas Edward Nelson Jan 2011

Electrochemical Studies Of Quinone On Clay-Modified Platinum Electrodes, Thomas Edward Nelson

Theses (2 year embargo)

No abstract provided.


Analysis Of Gaba And Glutamate In The Mouse Dorsal Striatum, Stella Wisidagamage Jan 2011

Analysis Of Gaba And Glutamate In The Mouse Dorsal Striatum, Stella Wisidagamage

Wayne State University Theses

ABSTRACT

ANALYSIS OF GABA AND GLUTAMATE IN MICE BRAIN

by

STELLA WISIDAGAMA

May 2011

Advisor: Dr. Tiffany Mathews

Major: Chemistry (Analytical)

Degree: Master of Science

GABA and glutamate are the predominant inhibitory and excitatory amino acid neurotransmitters in the central nervous system (CNS), respectively. However, their altered levels cause several neurological diseases including Parkinson's and Huntington's disease, schizophrenia, and epilepsy. It is important to measure their levels in the extra- and intracellular environments to better understand and develop improved therapeutics that will treat these neurological disorders. The principle aim of this study is to study the impacts of different endogenous …


Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel Jan 2011

Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel

Open Access Theses & Dissertations

In the last two decades, synchrotron based techniques have gained popularity and been increasingly used in environmental sciences. The present dissertation has relied significantly in the use of synchrotron based techniques to study the speciation, coordination, and distribution of toxic metal(loids) in plants. This study included three plant species: Parkinsonia florida, Prosopis juliflora, and Zea mays. P. florida is a plant species native to the semi-desert regions of North America. The cultivation characteristics of this shrub/tree suggest that it could be used for phytoremediation purposes in semiarid regions. P. florida plants were tested for their capacity to remove arsenic (As) …


Quality Of Wastewater In The El Paso, Texas Region--Analysis Of Pharmaceuticals And Personal Care Products Using High Performance Liquid Chromatography Tandem Mass Spectrometry, Rodolfo Guerrero Jr. Jan 2011

Quality Of Wastewater In The El Paso, Texas Region--Analysis Of Pharmaceuticals And Personal Care Products Using High Performance Liquid Chromatography Tandem Mass Spectrometry, Rodolfo Guerrero Jr.

Open Access Theses & Dissertations

Pharmaceuticals and Personal Care Products (PPCPs), such as household cleaning materials, prescription medication, and personal hygiene products, are pollutants of emerging concern that are found in 80% of our water system. Because of their applications, PPCPs are subsequently being released into wastewater; however, current wastewater treatment facilities are not regulated or designed to remove PPCPs. Therefore, these compounds are discharged into the environment on a continual basis. The effects of PPCPs on human health are not yet well known; however, recent research has found that exposure to these chemicals has some adverse developmental effects on aquatic species at low concentrations …


Optimization And Validation Of Direct Analysis In Real Time Mass Spectrometry (Dart-Ms) For Quantitation Of Sugars To Advance Biofuel Production, Daudi Sayialel Saang'onyo Jan 2011

Optimization And Validation Of Direct Analysis In Real Time Mass Spectrometry (Dart-Ms) For Quantitation Of Sugars To Advance Biofuel Production, Daudi Sayialel Saang'onyo

Online Theses and Dissertations

A direct analysis in real time mass spectrometry method was developed and validated for the analysis and quantitation of sugars that would be generated from pretreated and hydrolyzed switchgrass. This research aspect can be divided into two sections:

i) Literature Review: A review is presented on the status of energy security and how biomass and biofuels can be utilized as a source of transportation fuel. To this end, biomass (specifically switchgrass) can be broken down by pretreatment methods and then enzymatically hydrolyzed to simple sugars. These sugars can assist with algae growth that can eventually be converted into biofuels. …


Development, Validation And Application Of Uhplc-Ms/Ms Methods For The Detection Of Veterinary Drug Residues In Food Of Animal Origin, Michelle Whelan Jan 2011

Development, Validation And Application Of Uhplc-Ms/Ms Methods For The Detection Of Veterinary Drug Residues In Food Of Animal Origin, Michelle Whelan

Theses

Ultra high pressure liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-MS/MS) technology was utilized for the development of analytical methods for the detection of veterinary drug residues in foods of animal origin. Initial work focused on the development of the mass spectrometry (MS) method for the detection of the analytes of interest and subsequent chromatographic separation. The MS method was optimised to detect both positively and negatively ionised analytes from different classes in a single injection in a 13 minute run time at μg kg-1levels.

Sample preparation procedures were modified to extract the residues from muscle and …


High Resolution Hybrid Mass Spectrometry For The Determination Of Marine Biotoxins, Azaspiracids, And Their Biotransformation Products., Zuzana Skrabakova Jan 2011

High Resolution Hybrid Mass Spectrometry For The Determination Of Marine Biotoxins, Azaspiracids, And Their Biotransformation Products., Zuzana Skrabakova

Theses

Azaspiracids (AZAs), polyether marine toxins, are produced by marine microalgae and accumulate in filter-feeding bivalve molluscs, such as mussels, clams, oysters and scallops, while grazing on phytoplankton, from which they derive nutrition. Although being discovered quite recently, AZAs have caused several human intoxication events and thus became a problem for health authorities and shellfish industries. The rapid development of highly sensitive liquid chromatography multiple tandem mass spectrometry (LC-MS/MS, LC-MS") methods enabled the identification of numerous AZA analogues and added to the control of shellfish contamination. Tandem mass spectrometry techniques, while being highly selective and sensitive for determination of AZAs in …


Nmr Solution Structures Of Two Hairpins Of E. Coli 16s Rrna: The Effects Of Mutations And Chemical Modifications On Structure And Function Of Rrna, Yu Liu Jan 2011

Nmr Solution Structures Of Two Hairpins Of E. Coli 16s Rrna: The Effects Of Mutations And Chemical Modifications On Structure And Function Of Rrna, Yu Liu

Wayne State University Dissertations

The structures of two functional mutants, the UC (G690U, U697C) and the QM mutants (G690A, G693C, A695C, U697A) of the 690 hairpin of E. coli 16S ribosomal RNA were determined by NMR. The UC mutant and the QM mutant with high biological function are able to fold into structures that are isomorphous with the wild-type 690 hairpin sequence. The structural comparisons among the functional mutants and the wild-type provides structural validation for previously identified specific functional groups that are crucial for maintaining function of the 690 hairpin. The key groups for maintaining the structure and function of the 690 loop …