Digital Commons Network^™

Stealth Carbon Nanotubes: Strategies To Coat Carbon Nanotubes To Prevent Opsonization And Improve Biodistribution, Nalinikanth Kotagiri

Graduate Theses and Dissertations

Carbon nanotubes (CNT) have recently been in the limelight for its potential role in disease diagnostics and therapeutics. Even before these medical applications can be realized, there is a need to address issues like opsonization, phagocytosis by macrophages and sequestration to liver and spleen for eventual elimination from the body. We believe coating CNT with biocompatible and opsonin resistant moieties will not only help CNT in traversing the blood stream to reach the target organ, but also improve biodistribution tremendously. We set out to achieve this by firstly identifying a new compound, mAmp, which is a fluorescent derivative of the …

The Role Of Albino3 And The Lipid Environment In Chloroplast Signal Recognition Particle Targeting, Nathan Lewis

Graduate Theses and Dissertations

Signal recognition particles (SRPs) in pro- and eukaryotes function in cotranslational targeting of nascent poplypeptides to an SRP receptor at the target membrane. A unique chloroplast SRP (cpSRP) functions post-translationally to direct light-harvesting chlorophyll-binding proteins (LHCPs) to the receptor cpFtsY at the thylakoid membrane for LHCP insertion in a process involving the integral membrane protein Albino3 (Alb3) and requiring GTP. Work here focuses on understanding cpSRP targeting events at the thylakoid membrane, specifically those involving Alb3 and the lipid environment.

We show an interaction between the novel cpSRP subunit cpSRP43 and the soluble, stromal-exposed C terminus of Albino3 (Alb3-Cterm). We …

Tryptophan Anchored Peptides In Lipid Bilayer Membranes: Control Of Peptide Orientation And The Phase Behavior Of Cholesterol-Containing Ternary Lipid Mixtures, Johanna Maria Rankenberg

Graduate Theses and Dissertations

Model WALP peptides and "next generation" WALP-derived hydrophobic model peptides were employed to discover principles that govern protein-lipid interactions in biological membranes.

Ternary cholesterol-containing lipid mixtures were examined in the presence of WALP peptides of different lengths (acetyl-GWW(LA)_nLWWA-ethanolamide, with n between 3 and 8). Deuterium NMR spectra from labeled lipids reveal that WALP peptides may stabilize lipid ordered "raft" domains and therefore promote lipid phase separation, albeit to a minor extent. The results depend upon whether dioleolyl- or diphytanoyl-phosphatidylcholine is present as the fluid lipid component.

Several WALP peptides were modified to remove anchoring Trp residues from one …

Applications Of Site-Specific Recombination Systems In Transgene Expression And Marker Gene Removal, Mehmet Aydin Akbudak

Graduate Theses and Dissertations

Site Specific Recombination systems, such as FLP-FRT and Cre-lox, have been successfully used for site-specific gene integration and marker-gene deletion in plant systems. They are very useful tools in the integration of single-copy full-length transgene cassettes into the genome because the transgene integration via conventional methods often generate multi-copy locus. Such complex locus containing direct and inverted repeats of full-length and truncated copies of the transgene cassette generate aberrant RNA resulting in gene silencing. Therefore, for stable gene expression, a single copy transgene locus is preferred. However, even single copy locus sometimes succumbs to gene silencing. Although the mechanism is …

Intraspecific Variation In Two Cosmopolitan Myxomycetes, Didymium Squamulosum And Didymium Difforme (Physarales: Didymiaceae), Katherine Elizabeth Winsett

Graduate Theses and Dissertations

The myxomycetes (plasmodial slime molds or myxogastrids) are one of three groups considered to be true slime molds (class Eumycetozoa sensu Olive 1975). Two vegetative states--amoebae and plasmodia--along with a spore-producing fruiting body characterize the life cycle of the myxomycetes. These organisms are associated with decaying plant material and are found in all terrestrial habitats worldwide. A number of species are considered cosmopolitan, being found worldwide, where they are associated with a diversity of microhabitats and substrates. A review of the literature, including molecular investigations in all three groups of slime molds, is presented, and this is followed by four …

Characterization And Functional Regulation Of Bioactive Peptides In Avian Macrophages And Heterophils, Lakshmi Kannan

Graduate Theses and Dissertations

Oligopeptides and low molecular weight polypeptides play central roles as effectors and signal transducers acting as hormones, neurotransmitters, growth factors, toxins, and antimicrobial factors that are important for the survival of the organism. Owing to the ubiquitous involvement of peptides in many key regulatory processes, we have been interested to identify native peptides in different cells and tissues and understand their functions. To conduct our studies, we used avian macrophages and heterophils as models of specialized cells which constitute central components of innate immunity. These studies involved (a) qualitative identification and characterization of the peptides associated with high intensity mass …