Microbiology Commons^™

The Isolation And Characterization Of The Microbial Flora In The Alimentary Canal Of Gromphadorhina Portentosa Based On Rdna Sequences., Amy Renee Robertson

Electronic Theses and Dissertations

Multicellular organisms are not single individuals but carry a complex natural microflora with them. This complex's diversity and function can be considered a distinct ecosystem. Traditional methods of isolation and identification miss >90% of the actual diversity. This study uses the gut microflora of the Madagascar hissing roach, Gromphadorhina portentosa, as a model to examine this ecosystem. Isolated cultured bacteria were used to establish methods for identifying members of the microflora based on ribosomal RNA sequences. Universal primers for Eubacterial, Archaeal, and Eukaryotic 16s/18s rRNA were then used for PCR amplification of total DNA isolated from gut contents. Sequences …

Fungal Conversion And Supercritical Carbon Dioxide Processing For Value-Added Canola Oil, Meidui Dong

All Dissertations

There is a growing awareness of health benefits of polyunsaturated fatty acids (PUFAs) e.g. arachidonic acid (ARA, C20:4n6) and eicosapentaenoic acid (EPA, C20:5n3). In general, plant seed oil and animal fat do not contains long-chain PUFAs with more than eighteen carbons. This study investigated the feasibility for addition of ARA and EPA to canola oil through the fermentation of fungi, Mortierella alpina, using canola flake, cake or meal as substrates. Supercritical CO2 extraction was also investigated for lipid extraction. In addition, a supercritical CO2 explosion process was characterized and applied to enhance oil extraction using supercritical CO2 and to potentially …

The Effect Of Febrile Temperature On Plasmodium Falciparum, Heidi Sue Porter

Theses and Dissertations

Previously it has been shown that cultures of Plasmodium falciparum died following exposure to a febrile temperature of 40°C, as demonstrated by a decrease in parasitemia of the following generation. In the current study, the effect of 40°C treatment on culture media, erythrocytes, and parasite glucose consumption, were ruled out as possible influences on parasite death, demonstrating that 40°C impacted the parasites directly. Metabolic profiling of DNA synthesis, protein synthesis, and glucose utilization during exposure to 40°C clearly indicated that febrile temperatures had direct effect on major metabolic pathways and parasite development, beginning 20-24 hr after erythrocyte invasion. The ring …

Biophysical Study Of The Sh2 Domain Of Human Tensin, Yogesh Mohan Kulkarni

Doctoral Dissertations

Cell migration is a key characteristic of embryogenesis, inflammation, wound healing, tumor cell metastasis and a broad range of other normal and pathological processes. Accumulating evidence suggests that the protein tensin provides a physical link between transmembrane receptors, proteins commonly associated with signal transduction, and the actin cytoskeleton. Adhesion involves three broad classes of macromolecules: ExtraCellular Matrix (ECM) molecules, transmembrane adhesion receptors, and intracellular adhesion plaque proteins. Tensin is particularly enriched in Fibrillar Adhesions (FA's), though it is also present to a modest extent in Focal Contacts (FC's). Src Homology 2 (SH2) domains function in the transmission of molecular signals …

The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Mediates The Activity Of Chloroquine-Resistance Reversal Agents In The Malaria Parasite, Kristin Lane

Biological Sciences Theses & Dissertations

Chloroquine (CQ) resistant Plasmodium falciparum is a serious problem affecting 3.2 billion people in over 100 countries today. Most endemic malarious countries are among the poorest in the world and lack the resources to replace the inexpensive and highly effective CQ. CQ resistance (CQR) reversal agents are a potentially inexpensive solution to restoring CQ efficacy. CQR reversal agents are drugs that have little to no antimalarial activity alone, but in combination with CQ, they increase dmg accumulation in the parasite and enhance the sensitivity to CQ in CQR parasites. PfCRT is a putative transporter located on the parasite digestive vacuole …

Antimicrobial Activity Screening Of Recombinant And Synthetic Varasin A Defensin From The Hard Tick Dermacentor Variabilis Against Various Bacteria, Julia A. Sharp

Biological Sciences Theses & Dissertations

Hematophagous arthropods, such as ticks and mosquitoes, rely on their innate immune system for defense against pathogens ingested in a blood meal as well as those acquired through injury. In response to pathogen recognition, the production of antimicrobial peptides, such as defensin, is typically upregulated. Varisin, a defensin, is thought to be a key component in the immunocompetence of the hard tick D. variabilis against Borrelia burgdorferi, the causative agent of Lyme disease. To study the antimicrobial effects of varisin, recombinant varisin was expressed by both insect cells and E coli. Purification of the protein followed by enterokinase treatment yielded …

Isolation Of An Anti-Cd20 Single Chain Variable Fragment From A Naive Human Phage-Scfv Library, Amma Bosompem

All Theses

CD20 is a non-glycosylated transmembrane protein expressed on normal B cells, malignant B cells, and plasma cells, but not their stem cell precursors. It is an ideal target for antibody therapy because it is not significantly shed or internalized, and CD20 expression is generally not lost after antibody binding. Depleted B cells can also be regenerated after antibody therapy. Rituximab, a chimeric monoclonal antibody against CD20, was the first monoclonal antibody to be approved by the FDA for lymphoma. Results from clinical trials have shown that anti-CD20 monoclonal antibodies, which can be used unchanged or as carriers for radionuclides or …

The Antibacterial Properties Of Brookite Phase Titanium Dioxide Nanoparticles Against Methicillin-Resistant Staphylococcus Aureus, Rupal Shah

All Theses

Staphylococcus aureus (S. aureus), a major human pathogen, is a common cause of infections worldwide due to its high virulence intensity. By adapting to rapidly changing and uniformly hostile environments, strains of S. aureus acquire resistance to antimicrobial agents shortly after their exposure. For example, within a year of its introduction, S. aureus developed resistance to methicillin which triggered the development of other antimicrobial treatments. In spite of the various antibiotics currently used to treat methicillin-resistant S. aureus (MRSA) infections, antimicrobial resistance is an unavoidable consequence due to the selective pressure of antibiotic exposure. Thus, other prevention modalities are warranted …

Differential Response Of Various Spore Species To Sporicidal Disinfectants, Michael David Pratt

Theses and Dissertations

In the fall of 2001, letters laced with anthrax spores were delivered to various news organizations in New York and Florida, as well as to two Senators in Washington, D.C. Over 22 anthrax infections and five deaths resulted from exposure to these spores, and decontamination of the affected buildings was both time consuming and costly. Since these attacks, interest in sporicidal disinfectants has increased greatly. Many chemical sporicidal disinfectants are available commercially, but the exposure time required to sterilize can be relatively long. In addition, some spores are simply injured or inhibited by chemical disinfectants, but not necessarily killed. Studies …

Lipid Microdomains Are Involved In Adhesion Of Entamoeba Histolytica Trophozoites To Host Extracellular Matrix Components, Kriti Mittal

All Theses

Entamoeba histolytica is a parasitic human protozoan that infects 500,000,000 people worldwide annually. In the course of the parasite's life cycle, motile trophozoites breach the colonic mucosa, invade through the epithelial layer and extracellular matrix (ECM) and occasionally disseminate through portal blood vessels to distant organs. Membrane rafts are small heterogeneous, highly dynamic, sterol- and sphingolipid- enriched domains whose functional significance entails compartmentalization of cellular processes and regulation of cellular signaling. Recent studies reveal the physiological role of membrane rafts in adhesion to host epithelium in E. histolytica. In the current study we examined the role of lipid rafts …

Laboratory And Field Responses Of Target And Non-Target Species To Algaecide Exposures, Bryand Duke

All Dissertations

In order for water resource managers to effectively and efficiently react to algal growths that are prohibiting use of a lake, reservoir or stream, information must be obtained on the response of the specific algae in site waters to algaecide exposures. In the absence of this information, ineffective algaecides or excessive treatments may be implemented. Research on development of an efficient algaecide assay using site specific samples could contribute to better decisions regarding algaecide applications and increase margins of safety for non-target species. Since these laboratory experiments provide predictions of responses of algae in site waters to algaecide exposures, these …

Construction Of Bacteriophage-Based Bioluminescent Bioreporters For Staphylococcus Aureus And Salmonella Monitoring, Aysu Ozen

Doctoral Dissertations

Construction of two recombinant luxI bacteriophage-based bioluminescent bioreporters was undertaken to develop detection and monitoring systems for Staphylococcus aureus and Salmonella spp. These systems take advantage of the high specificity of bacteriophage for their hosts and the Vibrio fischeri lux operon responsible for quorum sensing bioluminescence. The detection system is composed of two elements, a recombinant phage with luxI which is specific for the target pathogen, and an acylhomoserine lactone (AHL)-inducible bioreporter cell line carrying the reporter lux genes. The goal of this study was to construct Salmonella- and S. aureus-specific recombinant phages which contain luxI.

The …

The Role Of Soluble Fibrin In Lymphocyte And Lak Cell Adherence To And Migration Across Vascular Endothelial Cells: Implications For Immunotherapy And Cancer, Brandy Lee Weidow

Masters Theses

Although conventional therapies for metastatic cancers have made significant progress in recent years, they are relatively nonspecific and have many deleterious side-effects. Recently, novel therapies, including adoptive cellular immune therapies have had sporadic, but spectacular success in cancers such as malignant melanoma and renal cell carcinoma: tumors in which an immune response has been demonstrated. However, other physiological mechanisms, such as blood coagulation inhibit the immune response against cancers. Our previous work has shown that one of these coagulation proteins, soluble fibrin (sFn), inhibits unstimulated and activated lymphocyte adherence to tumor cells by blocking leukocyte integrin (CD11a/CD18) binding to tumor …

Characterization Of A Novel Nuclear Variant Of Bmp2 And Coordinate Regulation Of Col11a2 And Col27a1 By The Transcription Factor Lc-Maf, Jaime Lynn Mayo

Theses and Dissertations

ABSTRACT I CHARACTERIZATION OF A NOVEL NUCLEAR VARIANT OF BMP2

Bone morphogenetic protein 2 (Bmp2) is a signaling protein that was first detected by its ability to induce cartilage and bone formation. It has since been implicated in broad variety of developmental, patterning, and disease processes. To date, Bmp2 has only been known to function as an extracellular signaling molecule. However, we have obtained clear evidence for a nuclear form of Bmp2. This nuclear variant, nBmp2, contains a bipartite NLS that overlaps the site of proteolytic cleavage. The NLS remains intact and functional when translation of Bmp2 initiates from a …

Serotype Association And Regulation Of The Hyaluronate Lyase Gene Of Streptococcus Pyogenes, Martha Stokes

Theses and Dissertations in Biomedical Sciences

S. pyogenes expresses many virulence factors, controlled by a complex regulatory network. These include hyaluronate lyase, an enzyme that degrades hyaluronic acid, a major component of the human extracellular matrix. Paradoxically, hyaluronic acid is also the sole component of the bacterium's capsule, a primary defense against the host immune response. The hylA gene, which encodes the enzyme, has been shown to take three structural forms: a full-length gene, one containing a 3' deletion and a gene that produces a prematurely truncated protein. This work was intended to show that the structure of hylA is associated with serotype, and …

The Microbiological Analysis Of Composting, Marion Shepherd

All Theses

The objectives of this study were to: 1) perform a survey of South Carolina poultry farms to determine if the methods implemented resulted in the destruction of foodborne pathogens, and 2) determine the survival of E. coli O157:H7 in a dairy manure-based compost performed in uncontrolled environmental conditions.
In the survey of poultry farms Ninety-one (91) of 141 compost samples analyzed were positive for coliform populations ranging from 1.00 to 6.00 log10 CFU/g. Among finished compost samples (n=21), ca. 62%, 33%, and 14% were positive for coliforms, presumptive Salmonella, and presumptive Listeria, respectively.
In the investigation of the survival of …

Biogeography And Genetic Diversity Of Toxin Producing Cyanobacteria In A Laurentian Great Lake, Johanna Maaria Rinta-Kanto

Doctoral Dissertations

The North American Great Lakes are a vital source on a global scale, as they hold ~18 % of the potable water resources on our planet. Cyanobacteria of the genus Microcystis are commonly found in fresh water environments around the world, and since the mid-1990s also in Lake Erie. The reasons for the success for these potentially toxic cyanobacteria in Lake Erie are not completely understood. In this study we have applied modern molecular tools to analyze field samples to provide an insight into the genotypic composition and diversity of the Microcystis community in the past and present day Lake …

Conservation Of The Sos Operon, Umudc, In Acinetobacter Species, Ching-Li Lin

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science & Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Ching-Li Lin on May 1, 2007.

Scanning Probe Microscopy: Applications For Genomic Research, David Post Allison

Doctoral Dissertations

The inauguration of the International Human Genome Initiative in the later part of the 1980’s coincided with the development of scanning probe microscopy (SPM). SPM was a good fit as one of the new technologies that might be implemented to sequence or map DNA and perhaps make a major contribution toward the goal of sequencing the entire human genome. Although the scanning tunneling microscope (STM) was invented in 1982 [Binnig 1982] and the atomic force microscope (AFM) in 1986 [Binnig 1986], it was not until 1987 that the first STM became commercially available; the AFM became available in 1989.

Our …

The Effect Of Radiation And Repeated Sub-Culturing On Tgf-Β1 Signaling In Frtl-5 Cells, Cheryl G. Burrell

Loma Linda University Electronic Theses, Dissertations & Projects

From our ongoing in vitro studies using the Fisher Rat Thyroid cell line-5 (FRTL-5) we recorded accelerated growth, reduced follicularization and reduction in thyroxin release that occurred as the cells were repeatedly sub-cultured. We also recorded that these changes occurred earlier and more rapidly following radiation exposure. We determined that TGF-β1 production increased under both conditions. We hypothesized that alteration in the TGF-β1 signaling pathway contributed to the changes observed in the cellular properties of FRTL-5 cells. Our objective was to examine some of the players in the TGF-β1 signaling pathway to determine whether radiation and/or repeated subculturing promoted changes …

Radiation-Induced Increases In Pkc Modulate Integrin Expression And Contribute To Fibrotic Changes, Pinal Rushikesh Pandya

Loma Linda University Electronic Theses, Dissertations & Projects

The sequences of events in fibrosis are similar to those in wound healing; however, the normal termination and resolution stages do not take place. The initial cellular response following ionizing radiation involves accumulation of the ECM (extracellular matrix) including collagen, fibronectin and the interaction of many growth factors (cytokines) with their receptors. There are a number of unanswered questions regarding many aspects of radiation-induced fibrosis, including the initial triggers and physical changes that initiate the process. We have confirmed that elevated pKC and other cellular changes following radiation are similar to those found at sites of inflammation. This information leads …

An Infection Model For Examining The Effects Of Gender And Diabetic State On Proinflammatory Cytokine Secretion By Phagocytic Cells In Response To Infection With Burkholderia Pseudomallei, Laura L. Dickey

Theses and Dissertations

Burkholderia pseudomallei is an opportunistic soil pathogen that causes melioidosis, a life-threatening human disease prevalent in Southeast Asia, northern Australia, the Middle East, Africa, and South America. The organism also causes disease in plants and animals. Persons with severe melioidosis usually die of septicemia. Relatively little is known regarding the virulence mechanisms of B. pseudomallei; however, several putative virulence determinants have been identified. The organism is able to invade and replicate within phagocytic cells and is particularly pathogenic in males with diabetes mellitus. B. thailandensis is closely related to B. pseudomallei, but is not pathogenic. This study examines various in …

Bactericidal Effects Of Cold Plasma Technology On Geobacillus Stearothermophilus And Bacillus Cereus Microorganisms, Angela Dawn Morris

Dental Hygiene Theses & Dissertations

Non-equilibrium atmospheric pressure plasma, also known as cold plasma, is a state of matter that consists of a mix of neutral and charged particles. Plasma generates chemically reactive species and ultraviolet radiation making them useful in decontamination applications (Kong & Laroussi, 2003). Research regarding the inactivation of gram-positive bacteria, such as Bacillus atrophaeus, by cold plasma has been studied by Laroussi et al. (2003); however, there is limited research regarding the germicidal effectiveness of cold plasma on the microorganisms Geobacillus stearothermophilus and Bacillus cereus. The purpose of this study was to determine if cold plasma technology inactivates heat …

Ecology Of Culturable Organisms At Rozel Point, Great Salt Lake, Utah, Emily Sarah Haws

Theses and Dissertations

The study of organisms from extreme environments is an emerging field of research with applications to multiple scientific areas. One of these extreme environments is Great Salt Lake (GSL), whose microbiology has yet to be extensively studied. This dynamic and unique environment offers an excellent opportunity to increase understanding of hypersaline ecology. Cultivation of microorganisms remains an important part of ecology research, as it is essential for understanding microbial physiology. We report here the culturing and characterization of isolates from Rozel Point, located on the northeastern shore of Great Salt Lake. This site was chosen because of the presence of …

The Role Of Prolactin In Ccl28 Regulation, Jennie Hyde

Theses and Dissertations

Infants are born with naive immune systems, making them susceptible to a variety of infections. In order to protect the newborn infant it is important that mothers be able to pass protective IgA antibodies to their infants through breast milk. B cells that produce IgA enter the mammary tissue during lactation and secrete IgA into the milk. During pregnancy, the mammary tissue expresses high levels of chemokines, molecules that allow lymphocytes to selectively home to specific tissues. The chemokine CCL28 has been shown to be upregulated during both pregnancy and lactation, and is vital for the ability of IgA-producing B …

Identification Of Genes Encoding Acyl-Coa Reductases And Aldehyde Reductases In Mycobacterial Genome By Characterization Of The Reductases Expressed In E. Coli, Harminder Singh

Electronic Theses and Dissertations

Mycobacterium tuberculosis has been long known to produce wax esters. However, the enzymes involved in their biosynthesis have not been identified. Here we report the identification of Rv3391 and Rv1543 as genes that encode fatty acyl-CoA reductases and Rv1544 as one that encodes an aldehyde reductase. When expressed in E.coli, the products of Rv3391 and Rv1543 catalyzed reduction of fatty acyl-CoA to fatty alcohol with the corresponding aldehyde as an intermediate with an optimal pH of 7.0. Both enzymes showed a strong preference for NADPH over NADH as a reductant. Apparent Km for NADPH was 38 [micro]M for Rv3391 product …

The Effects Of Trivalent Arsenicals And Thioredoxin Reductase Inhibitors On Selenium Metabolism In Lung Cell Culture Models, Sarah Ryann Talbot

Electronic Theses and Dissertations

Arsenic exposure, through various routes, is associated with the development of cancer of the skin, lung, liver, kidney, and bladder. Treatment of cells in culture with trivalent arsenicals has been shown to increase reactive oxygen species (ROS). In particular, monomethylarsonous acid (MMAIII), a trivalent metabolite of arsenite, is highly cytotoxic and possibly carcinogenic. Three trivalent arsenicals; arsenite, arsenic trioxide (ATO), and MMAIII, are also known inhibitors of the selenoprotein thioredoxin reductase (TrxR). Selenium, an essential micronutrient in mammals, is needed in the form of selenocysteine for activity of this enzyme and other selenoproteins. TrxR is part of a key component …

Physical Characteristics Of An Individual: The Identification Of Biomarkers For Biological Age Determination, Michelle Alvarez

Electronic Theses and Dissertations

It is now a matter of routine for the forensic scientist to obtain the genetic profile of an individual from DNA recovered from a biological stain deposited at a crime scene. Potential contributors of the stain must either be known to investigators (i.e. a developed suspect) or the questioned profile must be searched against a database of DNA profiles such as those maintained in the CODIS National DNA database. However, in those instances where there is no developed suspect and no match is obtained after interrogation of appropriate DNA databases, the DNA profile per se presently provides no meaningful information …

Correlation Of Rpob Gene Mutation With Clinical Rifabutin And Rifampicin Resistance For Treatment Of Crohn's Disease, Daniel Beckler

Electronic Theses and Dissertations

Emerging rise in microbial drug resistance and the slow-growing characteristic of some intracellular pathogens such as MAP (Mycobacterium avium subspecies paratuberculosis) strongly urges the need for an effective approach for unconventional drug susceptibility testing. We designed a molecular-based PCR method for the evaluation of rifabutin (RFB) and rifampicin (RIF) resistance based on probable determinant regions within the rpoB gene of MAP, including the 81 bp variable site located between nucleotides 1363 and 1443. The minimum inhibitory concentration (MIC) for RIF was also determined against 10 MAP isolates in attempt to seek correlation with rpoB sequences. We determined that MAP strain …

Mechanism Of Action And Regulation Of Membrane Serine Protease Prostasin In The Prostate And Prostate Cancer, Mengqian Chen

Electronic Theses and Dissertations

The glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin (PRSS8) is expressed at the apical membrane surface of epithelial cells and acts as a suppressor of tumor invasion when re-expressed in highly invasive human prostate and breast cancer cell lines. To better understand the molecular mechanisms underlying the anti-invasion phenotype associated with prostasin re-expression in prostate cancer cells, we expressed wild-type human prostasin or a serine active-site mutant prostasin in the PC-3 human prostate carcinoma cells. Molecular changes were measured at the mRNA and the protein levels. The expression of several invasion-promoting molecules is regulated by prostasin re-expression, mediated by a protein-level down-regulation …