Biochemistry, Biophysics, and Structural Biology Commons^™

Methanol And Ethanol Modulate Responses To Danger- And Microbe- Associated Molecular Patterns In Tomato, Tobacco And Arabidopsis, Claire Teresa Hann

Theses and Dissertations

Methanol is a byproduct of cell wall modification. It is released through the action of pectin methylesterases (PMEs), which demethylate cell wall pectins. Plant PMEs play not only a role in developmental processes but also in responses to herbivory and infection by fungal or microbial pathogens, resulting in increased methanol release. To break down the cell wall barrier, pathogens employ their own PMEs. Interestingly, the infection process also regulates the expression of certain plant PMEs. Methanol is toxic to a number of herbivores and reduces their fitness. At high concentrations, it upregulates signaling and defense genes. However, molecular mechanisms that …

Population Analysis And Protein Stability Assays Illustrate Xenobiotic Metabolizing Enzymes Have No Detectable Effect On Breast Cancer Development And Progression, Thomas Daniel Crowder

Theses and Dissertations

Xenobiotic Metabolizing Pathway works to detoxify the cell from numerous carcinogenic, mutagenic, and toxic hydrophobic compounds. As a member of the phase I enzymes (the first phase in the Xenobiotic Metabolizing Pathway) the Cytochrome P-450 Family 1 Sub-family B Protein 1 (Cyp1B1) works to attach an oxygen molecule to its hydrophobic substrate. In performing this reaction, Cyp1B1 often increases the reactivity of the xenobiotic compound. If these reactive Cyp1B1 products migrate into the nucleus and they can cause damage by reacting with DNA. However, the Glutathione S-Transferase Theta 1 (GSTT1) and Glutathione S-Transferase Mu 1 (GSTM1), members of the phase …

The Effects Of Salinity, Ph, Temperature, And Dissolved Oxygen On Sensitivity Of Pcr Identification Of T4 Bacteriophage, Joesph F. Cannon, Nicholas A. Thurn, Paul E. Richardson

Journal of the South Carolina Academy of Science

Bacteriophages are used as indicators of pathogenic bacteria in drinking, and wastewaters. They also show potential in limiting aquatic bacterial populations through their lytic properties. The effect of different water characteristics (salinity, pH, dissolved oxygen, and temperature) on the sensitivity of the PCR identification of virus particles were analyzed to determine at what levels bacteriophage can be detected in environmental samples. Results from this preliminary study indicate that a PCR bacteriophage detection technique has potential as a relatively efficient and economical indicator of coliform contamination in multiple aquatic environments. While further evaluation is needed, the protocol appears to function in …

A Supramolecular Strategy To Assemble Multifunctional Viral Nanoparticles, Limin Chen, Xia Zhao, Yuan Lin, Yubin Huang, Qian Wang

Faculty Publications

Using a one-pot approach driven by the supramolecular interaction between β-cyclodextrin and adamantyl moieties, multifunctional viral nanoparticles can be facilely formulated for biomedical applications.

Chelation Therapy For The Management Of Diabetic Complications: A Hypothesis And A Proposal For Clinical Laboratory Assessment Of Metal Ion Homeostasis In Plasma, Norma Frizzell, John W. Baynes

Faculty Publications

No abstract provided.

Expansion Of Breast Cancer Stem Cells With Fibrous Scaffolds, Sheng Feng, Pang-Kuo Lo, Shou Liu, Xinfeng Liu, Hexin Chen, Qian Wang

Faculty Publications

Cancer stem cells (CSCs) are hypothesized as tumor-initiating cells within tumors and main contributors of tumor growth, metastasis and recurrence. Mammary cancer cells, MCF-7 cells, were cultured on 3D polycaprolactone (PCL) fibrous scaffolds, showing an increased proportion of CSCs. The expression of stem cell markers, including OCT3/4 and SOX2, and breast CSC-specific markers, SOX4 and CD49f, was significantly upregulated, and the mammosphere-forming capability in cells cultured on PCL fibrous scaffolds increased. The fibrous scaffolds also induced the elongation of MCF-7 cells and extended cell proliferation. The increase of CSC properties after being cultured on fibrous scaffolds was further confirmed with …

Executing And Teaching Science--The Breast Cancer Genetics And Technology-Rich Curriculum Professional Development Studies Of A Science Educator, Regina Evarn Wragg

Theses and Dissertations

This dissertation presents my explorations in both molecular biology and science education research. In study one, we determined the ADIPOQ and ADIPORI genotypes of 364 White and 148 Black BrCa patients and used dominant model univariate logistic regression analyses to determine individual SNP and haplotype associations with tumor or patient characteristics in a case-case comparison. We found twelve associations between individual SNPs and patient or tumor characteristics that impact BrCa prognosis. For example, the ADIPOQ rs1501299 C allele was associated with ER+ tumors (OR=4.73, p=0.001) among White women >50 years of age at their time of diagnosis. Also, the A …

Tnt1 Retrotransposon Mutagenesis: A Tool For Soybean Functional Genomics, Yaya Cui, Shyam Barampuram, Minviluz G. Stacey, C. Nathan Hancock, Seth Findley, Melanie Mathieu, Zhanyuan Zhang, Wayne A. Parrott, Gary Stacey

Faculty Publications

Insertional mutagenesis is a powerful tool for determining gene function in both model and crop plant species. Tnt1, the transposable element of tobacco (Nicotiana tabacum) cell type 1, is a retrotransposon that replicates via an RNA copy that is reverse transcribed and integrated elsewhere in the plant genome. Based on studies in a variety of plants, Tnt1 appears to be inactive in normal plant tissue but can be reactivated by tissue culture. Our goal was to evaluate the utility of the Tnt1 retrotransposon as a mutagenesis strategy in soybean (Glycine max). Experiments showed that the …

An Acid Catalyzed Reversible Ring-Opening/Ring-Closure Reaction Involving A Cyano-Rhodamine Spirolactam, H. Li, H. Guan, X. Duan, J. Hu, Guiren Wang, Qian Wang

Faculty Publications

Cyanamide was introduced into the rhodamine spirolactam framework to produce a colorless and non-fluorescent compound RBCN. It shows a reversible ring-opening/ring-closure process in response to the solution pH, which exhibits an “ON/OFF” switching in its fluorescence. Different from other rhodamine-type dyes, the ring-open form of RBCN is stable in protic solvents under neutral, near neutral and basic conditions, showing a pink color and very strong fluorescence. We also demonstrated the potential of RBCN in live cell imaging.

Complex Of Myoglobin With Phenol Bound In A Proximal Cavity, Xiao Huang, Chunxue Wang, Lesa R. Celeste, Leslie L. Lovelace, Shengfang Sun, John H. Dawson, Lukasz Lebioda

Faculty Publications

Sperm whale myoglobin (Mb) has weak dehaloperoxidase activity and catalyzes the peroxidative dehalogenation of 2,4,6-trichlorophenol (TCP) to 2,6-dichloroquinone. Crystals of Mb and of its more active G65T variant were used to study the binding of TCP, 4-iodophenol (4-IP) and phenol. The structures of crystals soaked overnight in a 10 mM solution of phenol revealed that a phenol molecule binds in the proximal cavity, forming a hydrogen bond to the hydroxyl of Tyr146 and hydrophobic contacts which include interactions with C and C of the proximal histidine His93. The phenol position corresponds to the strongest xenon binding site, Xe1. It …

Breast Tumour Initiating Cell Fate Is Regulated By Microenvironmental Cues From An Extracellular Matrix, Sharmistha Saha, Pang-Kuo Lo, Xinrui Duan, Hexin Chen, Qian Wang

Faculty Publications

Cancer stem cells, also known as tumour-initiating cells (TICs), are identified as highly tumorigenic population within tumours and hypothesized to be main regulators in tumour growth, metastasis and relapse. Evidence also suggests that a tumour microenvironment plays a critical role in the development and progression of cancer, by constantly modulating cell–matrix interactions. Scientists have tried to characterize and identify the TIC population but the actual combination of extracellular components in deciphering the fate of TICs has not been explored. The basic unanswered question is the phenotypic stability of this TIC population in a tissue extracellular matrix setting. The in vivo …

Discrimination Of Colon Cancer Stem Cells Using Noncanonical Amino Acid, Xinrui Duan, Honglin Li, Hexin Chen, Qian Wang

Faculty Publications

Cancer stem cells (CSCs) may be responsible for tumor recurrence. Metabolic labelling of newly synthesized proteins with non-canonical amino acids allows us to discriminate CSCs in mixed populations due to the quiescent nature of these cells.

A Plant Virus Substrate Induces Early Upregulation Of Bmp2 For Rapid Bone Formation, Pongkwan Sitasuwan, L. Andrew Lee, Peng Bo, Erin N. Davis, Yuan Lin, Qian Wang

Faculty Publications

Many nanoscale materials have been developed to investigate the effects on stem cell differentiations via topographical and chemical cues for applications in tissue engineering and regenerative medicine. The use of plant viruses as cell supporting substrates has been of particular interest due to the rapid induction of bone marrow derived mesenchymal stem cells (BMSCs) towards osteogenic cells. In this study, the role of Tobacco mosaic virus (TMV) and its early effects on osteoinduction with particular emphasis on the regulation of bone morphogenetic protein-2 (BMP2) was examined. We observed that the cells on the virus substrate immediately aggregated and formed bone-like …

The Mechanical Properties Of Epoxy Composites Filled With Rubbery Copolymer Grafted Sio2, Jianing Gao, Junting Li, Brian C. Benicewicz, Su Zhao, Henrik Hillborg, Linda S. Schadler

Faculty Publications

This study demonstrated a method for toughening a highly crosslinked anhydride cured DGEBA epoxy using rubbery block copolymer grafted SiO2 nanoparticles. The particles were synthesized by a sequential reversible addition-fragmentation chain transfer (RAFT) polymerization. The inner rubbery block poly(n-hexyl methacrylate) (PHMA) had a glass transition temperature below room temperature. The outer block poly(glycidyl methacrylate) (PGMA) was matrix compatible. A rubbery interlayer thickness of 100% and 200% of the particle core radius was achieved by grafting a 20 kg/mol and a 40 kg/mol PHMA at a graft density of 0.7 chains/nm² from the SiO₂ surface. The 20 kg/mol rubbery …

Why Do We Collect?, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Imaging And Aesthetics, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Conclusion Panel, Allison Marsh

Section 6: Conclusion

No abstract provided.

The Rice Miniature Inverted Repeat Transposable Element Mping Is An Effective Insertional Mutagen In Soybean, C. Nathan Hancock, Feng Zhang, Kristen Floyd, Aaron O. Richardson, Peter Lafayette, Donna Tucker, Susan R. Wessler, Wayne A. Parrott

Faculty Publications

Insertional mutagenesis of legume genomes such as soybean (Glycine max) should aid in identifying genes responsible for key traits such as nitrogen fixation and seed quality. The relatively low throughput of soybean transformation necessitates the use of a transposon-tagging strategy where a single transformation event will produce many mutations over a number of generations. However, existing transposon-tagging tools being used in legumes are of limited utility because of restricted transposition (Ac/Ds: soybean) or the requirement for tissue culture activation (Tnt1: Medicago truncatula). A recently discovered transposable element from rice (Oryza …

Loose Ligands And Available Iron In The Ocean, Ronald Benner

Faculty Publications

No abstract provided.

Systematic Approach To Electrostatically Induced 2d Crystallization Of Nanoparticles At Liquid Interfaces, Sumit Kewalramani, Suntao Wang, Yuan Lin, Huong Giang Nguyen, Qian Wang, Masafumi Fukuto, Lin Yang

Faculty Publications

We report an experimental demonstration of a strategy for inducing two-dimensional (2D)crystallization of charged nanoparticles on oppositely charged fluid interfaces. This strategy aims to maximize the interfacial adsorption of nanoparticles, and hence their lateral packing density, by utilizing a combination of weakly charged particles and a high surface charge density on the planar interface. In order to test this approach, we investigated the assembly of cowpea mosaic virus (CPMV) on positively charged lipid monolayers at the aqueous solution surface, by means of in situX-ray scattering measurements at the liquid–vapor interface. Theassembly was studied as a function of the solution …

The Metal Chelators, Trientine And Citrate, Inhibit The Development Of Cardiac Pathology In The Zucker Diabetic Rat, John W. Baynes, David B. Murray

Faculty Publications

Purpose. The objective of this study was to determine the efficacy of dietary supplementation with the metal chelators, trientine or citric acid, in preventing the development of cardiomyopathy in the Zucker diabetic rat.

Hypothesis. We hypothesized that dietary chelators would attenuate metal-catalyzed oxidative stress and damage in tissues and protect against pathological changes in ventricular structure and function in type II diabetes.

Methods. Animals (10 weeks old) included lean control (LC, fa/+), untreated Zucker diabetic fatty (ZDF, fa/fa), and ZDF rats treated with either trientine (triethylenetetramine) or citrate at 20 mg/d in drinking water, starting …

Oriented Cell Growth On Self-Assembled Bacteriophage M13 Thin Films, Jianhua Rong, L. Andrew Lee, Kai Li, Brandon Harp, Charlene M. Mello, Zhongwei Niu, Qian Wang

Faculty Publications

Fibrillar M13 bacteriophages were used as basic building blocks to generate thin films with aligned nanogrooves, which, upon chemical grafting with RGD peptides, guide cell alignment and orient the cell outgrowth along defined directions.

Novel Role Of Antioxidant-1 (Atox1) As A Copper-Dependent Transcription Factor Involved In Cell Proliferation, S. Itoh, H. W. Kim, O. Nakagawa, K. Ozumi, Susan M. Lessner, H. Aoki, K. Akram, R. D. Mckinney, M. Ushio-Fukai, T. Fukai

Faculty Publications

Copper plays a fundamental role in regulating cell growth. Many types of human cancer tissues have higher copper levels than normal tissues. Copper can also induce gene expression. However, transcription factors that mediate copper-induced cell proliferation have not been identified in mammals. Here we show that antioxidant-1 (Atox1), previously appreciated as a copper chaperone, represents a novel copper-dependent transcription factor that mediates copper-induced cell proliferation. Stimulation of mouse embryonic fibroblasts (MEFs) with copper markedly increased cell proliferation, cyclin D1 expression, and entry into S phase, which were completely abolished in Atox1^-/- MEFs. Promoter analysis and EMSA revealed that copper …

1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Kis(Trifluoro­Meth­Yl)- 1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Hydro­(C60-IH)[5,6]Fullerene, Natalia B. Shustova Prof. Dr., O.P. Anderson, O. V. Boltalina, S. H. Strauss, I. E. Kareev

Faculty Publications

The title compound, C₇₂F₃₆, is one of four isomers of C₆₀(CF₃)₁₂ for which crystal structures have been obtained. The fullerene mol­ecule has an idealized I_h C₆₀ core with the 12 CF₃ groups arranged in an asymmetric fashion on two ribbons of edge-sharing C₆(CF₃)₂ hexa­gons, a para–meta–para–para–para–meta–para ribbon and a para–meta–para ribbon, giving an overall pmp ³ mp,pmp structure. There are no cage Csp ^{3 …}

Dynamics Of Dissolved Organic Carbon, Nitrogen And Phosphorus In A Seagrass Meadow Of Laguna Madre, Texas, Susan Ziegler, Edith Kaiser, Ronald Benner

Faculty Publications

No abstract provided.

Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber

Faculty Publications

n- and p-type Ge nanowires were synthesized by a multistep process in which axial elongation, via vapor–liquid–solid (VLS) growth, and doping were accomplished in separate chemical vapor deposition steps. Intrinsic, single-crystal, Ge nanowires prepared by Au nanocluster-mediated VLS growth were surface-doped in situ using diborane or phosphine, and then radial growth of an epitaxial Ge shell was used to cap the dopant layer. Field-effect transistors prepared from these Ge nanowires exhibited on currents and transconductances up to 850 µA/µm and 4.9 µA/V, respectively, with device yields of >85%.

Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka

Faculty Publications

Through the use of variable disulfide crosslinkers, we have created polyacrylamide gels whose shape can be altered after polymerization. N,N'-bisacryloylcystamine is incorporated as a crosslinker, along with a smaller amount of a permanent crosslinker. After polymerization, the disulfide bonds are cleaved into thiols through reduction. By reoxidizing the thiols with the gel held in a new macroscopic shape, a new set of disulfide bonds is formed, and the gel is forced to adopt the new shape. Retension of the new shape improves with greater distortion from the original shape, as well as with increased concentration of variable …

Principal Component Mapping Applied To Raman Microspectroscopy Of Fiber-Reinforced Polymer Composites, C. M. Stellman, K. S. Booksh, A. R. Muroski, M. P. Nelson, Michael L. Myrick

Faculty Publications

We describe the development and implementation of a spectroscopic Raman imaging system using Principal Component data analysis. Raman microspectroscopy followed by multivariate data analysis and principal component mapping has been used to investigate the spatial variations of chemical and physical properties at interfaces in glass-reinforced composites on the micrometer scale. A protocol for monitoring chemical and physical variances via multivariate statistics has been developed and a preliminary study of a "real world" glass-reinforced composite is presented. It is demonstrated that multivariate Raman imaging is more precisely interpretable than traditional univariate methods and that by appropriately choosing distinct spectral regions (such …

Isolation Of A Bacterium Capable Of Degrading Peanut Hull Lignin, Thomas J. Kerr, Robert D. Kerr, Ronald Benner

Faculty Publications

No abstract provided.