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2008

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Full-Text Articles in Life Sciences

Applying Marine Protected Area Design Models In Large Estuarine Systems, Roman Zajac, Amanda E. Neely Dec 2008

Applying Marine Protected Area Design Models In Large Estuarine Systems, Roman Zajac, Amanda E. Neely

Biology and Environmental Science Faculty Publications

Several types of design models are currently being used to develop marine protected areas (MPAs) for conservation of coastal and pelagic ecosystems. However, few studies have applied these models in large estuaries which have unique characteristics that need to be considered in MPA design, including strong physical, chemical and biological gradients and significant human impacts. We explored how one design model, MARXAN, can be applied to estuarine systems by developing MPA design scenarios for Long Island Sound, an estuary in the northeastern USA. Using sedimentary texture as a proxy for habitats, we modeled and tested several scenarios where conservation goals …


Ngasp - The Nematode Genome Annotation Assessment Project, Avril Coghlan, Tristan J. Fiedler, Sheldon J. Mckay, Paul R. Flicek, Todd W. Harris, Darin Blasiar, Lincoln D. Stein Dec 2008

Ngasp - The Nematode Genome Annotation Assessment Project, Avril Coghlan, Tristan J. Fiedler, Sheldon J. Mckay, Paul R. Flicek, Todd W. Harris, Darin Blasiar, Lincoln D. Stein

Biomedical Engineering and Sciences Faculty Publications

While the C. elegans genome is extensively annotated, relatively little information is available for other Caenorhabditis species. The nematode genome annotation assessment project (nGASP) was launched to objectively assess the accuracy of protein-coding gene prediction software in C. elegans, and to apply this knowledge to the annotation of the genomes of four additional Caenorhabditis species and other nematodes. Seventeen groups worldwide participated in nGASP, and submitted 47 prediction sets across 10 Mb of the C. elegans genome. Predictions were compared to reference gene sets consisting of confirmed or manually curated gene models from WormBase. Results: The most accurate gene-finders were …


Ecology Of The Evening Bat (Nycticeius Humeralis) At The Northern Edge Of The Range, Olivia Maya Munzer Dec 2008

Ecology Of The Evening Bat (Nycticeius Humeralis) At The Northern Edge Of The Range, Olivia Maya Munzer

Master's Theses and Doctoral Dissertations

Only a single colony of evening bats (Nycticeius humeralis) is known to occur in Michigan, and it is the northernmost colony on the North American continent. In mid-May, only female evening bats migrate to Michigan to raise their pups, and in late August, evening bats migrate to southern portions of their range, where they are ubiquitous. I studied the roosting and dietary ecology of the evening bat in southeastern Michigan. Evening bats roosted in cavities, crevices, and under exfoliating bark of older trees located in a bottomland forest, interlaced with waterways and surrounded by agricultural fields. These habitats …


Why Do Dolphins Carry Sponges?, Janet Mann, Brooke L. Sargeant, Jana J. Watson-Capps, Quincy A. Gibson, Michael R. Heithaus, Richard C. Connor, Eric Patterson Dec 2008

Why Do Dolphins Carry Sponges?, Janet Mann, Brooke L. Sargeant, Jana J. Watson-Capps, Quincy A. Gibson, Michael R. Heithaus, Richard C. Connor, Eric Patterson

Department of Biological Sciences

Tool use is rare in wild animals, but of widespread interest because of its relationship to animal cognition, social learning and culture. Despite such attention, quantifying the costs and benefits of tool use has been difficult, largely because if tool use occurs, all population members typically exhibit the behavior. In Shark Bay, Australia, only a subset of the bottlenose dolphin population uses marine sponges as tools, providing an opportunity to assess both proximate and ultimate costs and benefits and document patterns of transmission. We compared sponge-carrying (sponger) females to non-spongecarrying (non-sponger) females and show that spongers were more solitary, spent …


Changes In Biotic And Abiotic Processes Following Mangrove Clearing, Elise Granek, Benjamin I. Ruttenberg Dec 2008

Changes In Biotic And Abiotic Processes Following Mangrove Clearing, Elise Granek, Benjamin I. Ruttenberg

Biological Sciences

Mangrove forests, important tropical coastal habitats, are in decline worldwide primarily due to removal by humans. Changes to mangrove systems can alter ecosystem properties through direct effects on abiotic factors such as temperature, light and nutrient supply or through changes in biotic factors such as primary productivity or species composition. Despite the importance of mangroves as transitional habitats between land and sea, little research has examined changes that occur when they are cleared. We examined changes in a number of biotic and abiotic factors following the anthropogenic removal of red mangroves (Rhizophora mangle) in the Panamanian Caribbean, including …


Clustering Neural Spike Trains With Transient Responses, John D. Hunter, Jianhong Wu, John Milton Dec 2008

Clustering Neural Spike Trains With Transient Responses, John D. Hunter, Jianhong Wu, John Milton

WM Keck Science Faculty Papers

The detection of transient responses, i.e. nonstationarities, that arise in a varying and small fraction of the total number of neural spike trains recorded from chronically implanted multielectrode grids becomes increasingly difficult as the number of electrodes grows. This paper presents a novel application of an unsupervised neural network for clustering neural spike trains with transient responses. This network is constructed by incorporating projective clustering into an adaptive resonance type neural network (ART) architecture resulting in a PART neural network. Since comparisons are made between inputs and learned patterns using only a subset of the total number of available dimensions, …


The Impact Of Repeated Rounds Of Mass Drug Administration With Diethylcarbamazine Plus Albendazole On Bancroftian Filariasis In Papua New Guinea, Gary J. Weil, Will Kastens, Melinda Susapu, Sandra J. Laney, Steven A. Williams, Christopher L. King, James W. Kazura, Moses J. Bockarie Dec 2008

The Impact Of Repeated Rounds Of Mass Drug Administration With Diethylcarbamazine Plus Albendazole On Bancroftian Filariasis In Papua New Guinea, Gary J. Weil, Will Kastens, Melinda Susapu, Sandra J. Laney, Steven A. Williams, Christopher L. King, James W. Kazura, Moses J. Bockarie

Biological Sciences: Faculty Publications

Background: This study employed various monitoring methods to assess the impact of repeated rounds of mass drug administration (MDA) on bancroftian filariasis in Papua New Guinea, which has the largest filariasis problem in the Pacific region.

Methodology/Principal Findings: Residents of rural villages near Madang were studied prior to and one year after each of three rounds of MDA with diethylcarbamazine plus albendazole administered per World Health Organization (WHO) guidelines. The mean MDA compliance rate was 72.9%. Three rounds of MDA decreased microfilaremia rates (Mf, 1 ml night blood by filter) from 18.6% pre-MDA to 1.3% after the third MDA (a …


Production Of Marine Trematode Cercariae: A Potentially Overlooked Path Of Energy Flow In Benthic Systems, David W. Thieltges, Xavier De Montaudouin, Brian L. Fredensborg, K. Thomas Jensen, Janet Koprivnikar, Robert Poulin Dec 2008

Production Of Marine Trematode Cercariae: A Potentially Overlooked Path Of Energy Flow In Benthic Systems, David W. Thieltges, Xavier De Montaudouin, Brian L. Fredensborg, K. Thomas Jensen, Janet Koprivnikar, Robert Poulin

Biology Faculty Publications and Presentations

Parasites, in particular trematodes, are unseen but ubiquitous components of marine intertidal ecosystems. Although parasites are known to affect population dynamics and food web structure, their potential function as an unrecognized path of energy flow in these ecosystems is yet to be quantified. We use published data on rates at which trematodes produce free-swimming infective larvae (cercariae) that are released from their gastropod intermediate hosts to investigate patterns in cercarial output as a function of different variables, and to calculate the annual production of cercariae in different marine benthic systems. Across 18 trematode species, cercarial output (no. cercariae shed snail–1 …


Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo Dec 2008

Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo

Theses and Dissertations

Swimming performance strongly influences fitness in aquatic organisms and is closely tied to external body morphology. Although this connection has been closely examined at the individual and species level, few studies have focused on this relationship as it pertains to functional group assemblages. Using functional groups based on similarities in habitat use and morphology, I tested the hypothesis that swimming performance can be reliably predicted by functional group composition. I measured swimming performance as burst speed using a simulated predator attack and as prolonged speed using a step-endurance test in a laboratory flume. I measured morphology using geometric morphometric techniques. …


Trichomycetes From Lentic And Lotic Aquatic Habitats In Ontario, Canada, D. B. Strongman, Merlin M. White Dec 2008

Trichomycetes From Lentic And Lotic Aquatic Habitats In Ontario, Canada, D. B. Strongman, Merlin M. White

Biology Faculty Publications and Presentations

Fungi and protists make up an ecological group, trichomycetes, that inhabit the guts of invertebrates, mostly aquatic insects. Trichomycetes are reported herein from arthropods collected in lotic habitats (fast flowing streams) and lentic environments (ponds, ditches, seeps, and lakes) from 11 sites in Algonquin Park and 6 other sites in Ontario, Canada. Thirty-two trichomycete species were recovered, including 7 new species: Legeriomyces algonquinensis, Legeriosimilis leptocerci, Legeriosimilis whitneyi and Paramoebidium umbonatum are described from mayfly nymphs (Ephemeroptera); Pennella digitata and Glotzia incilis from black fly and midge larvae (Diptera), respectively; and Arundinula opeongoensis from a crayfish (Crustacea). Legeriomyces rarus Lichtw. & …


Does Light Control Algal Abundance In Large River Systems?, Amy Macdonald Dec 2008

Does Light Control Algal Abundance In Large River Systems?, Amy Macdonald

Theses and Dissertations

A limited amount of research has been done to investigate the factors influencing algal abundance in large river systems. This study examines light as the primary factor that controls algal abundance in the Upper Mississippi, Missouri and Ohio Rivers. Data were collected for 2004 in conjunction with the Environmental Monitoring Assessment Program- Great River Ecosystems EMAP-GRE project using EPA approved methods. Chlorophyll a concentrations were 34.6 µg•L-1 in the Upper Mississippi, 19.8 µg•L-1 in Missouri River and 9 µg•L-1 in the Ohio River for 2004. Chlorophyll a concentrations were significantly different among the three rivers (p<0.0001) but not between years. Inter-river variation could be loosely correlated with light availability: mean Average Irradiance Dosages, which consider factors that affect light climate (depth, transparency, velocity, surface irradiance), by river corresponded with mean chlorophyll a levels by river. Intra-river variation seemed to be due to both the influence of light and nutrients.


Mechanisms For Methylmercury Cell-To-Bath Transport By The Basolateral Membrane Of The Rabbit Proximal Tubule, Carol Ann Hoban Dec 2008

Mechanisms For Methylmercury Cell-To-Bath Transport By The Basolateral Membrane Of The Rabbit Proximal Tubule, Carol Ann Hoban

Biology Dissertations

The bath-to-cell transport, cytosolic concentration, and tubular content of methylmercury (Me203Hg+) and the sulfhydryl-amino acids and sulfhydryl-amino acid derivatives conjugated to Me203Hg+ were studied in the non-perfused S2 segments of the proximal tubule of the rabbit kidney. Active transport of Me203Hg+ was established by a temperature dependent (greater than 100% reduction in bath-to-cell transport, 99% decrease in cytosolic concentration, 63% decline in the tubular contents at 12°C when compared to 37°C). Conjugates of Me203Hg+ showed mixed results, with L-cysteine and L-taurine demonstrating the most significant increase in uptake. Transport of Me203Hg+-L-cysteine was also temperature dependent with a 77% reduction in …


Evaluation Of Methods For Establishing Vegetation In Created Wetland Mitigation Sites In Eastern Nebraska, Andrew A. Miller Dec 2008

Evaluation Of Methods For Establishing Vegetation In Created Wetland Mitigation Sites In Eastern Nebraska, Andrew A. Miller

Student Work

Seventeen wetland mitigation sites in eastern Nebraska were evaluated, by vegetative zone, to assess the relative success of active and passive wetland vegetation establishment techniques. For sites with available records of species introduced, 46% of the seeded species and 31% of the transplanted species were successfully established suggesting that the intentional introduction of species (i.e. active methods) provides some degree of success in wetland creation. No significant differences were observed within or among active or passive methods for Species Richness (S), Shannon-Wiener diversity (H′), or the Floristic Quality Index (FQI) (Kruskall-Wallis test P < 0.05). However, while not statistically significant, general trends showed that, in the temporarily flooded zones, seeding resulted in both the highest overall plant diversity and highest FQI (S = 20.2, H′ = 1.74, FQI = 8.99) and, among species with cover values > 0.5%, the lowest percent non-native species (6.2%). …


Current State Of Conservation Knowledge On Threatened Amphibian Species In Peru, Rudolf Von May, Alessandro Catenazzi, Ariande Angulo, Jason L. Brown, Jorge Carrillo, German Chavez, Jesus H. Cordova, Aleyda Curo, Amanda Delgado, Marco A. Enciso, Roberto Gutierrez, Edgar Lehr, Jorge L. Martinez, Margarita Medina-Muller, Alfonso Miranda, Daniel R. Neira, Jose A. Ochoa, Aaron J. Quiroz, Daniel A. Rodriguez, Lily O. Rodriguez, Antonio W. Salas, Tracie Seimon, Anton Seimon, Karen Siu-Ting, Juana Suarez, Claudia Torres, Evan Twomey Dec 2008

Current State Of Conservation Knowledge On Threatened Amphibian Species In Peru, Rudolf Von May, Alessandro Catenazzi, Ariande Angulo, Jason L. Brown, Jorge Carrillo, German Chavez, Jesus H. Cordova, Aleyda Curo, Amanda Delgado, Marco A. Enciso, Roberto Gutierrez, Edgar Lehr, Jorge L. Martinez, Margarita Medina-Muller, Alfonso Miranda, Daniel R. Neira, Jose A. Ochoa, Aaron J. Quiroz, Daniel A. Rodriguez, Lily O. Rodriguez, Antonio W. Salas, Tracie Seimon, Anton Seimon, Karen Siu-Ting, Juana Suarez, Claudia Torres, Evan Twomey

Department of Biological Sciences

This study documents the current state of conservation knowledge on threatened amphibian species in Peru. Following the International Union for the Conservation of Nature (IUCN) classification system, we considered species in the following categories: Critically Endangered, Endangered, Vulnerable, and Near Threatened. Even though only the first three categories are regarded as threatened by IUCN, we included the fourth category to make comparisons with the list of threatened species issued by the Peruvian government. We used the Global Amphibian Assessment's database and the list issued in Peru for this comparison. We conducted separate field surveys in 17 regions of Peru to …


Comparison Of Fish Assemblages In Two Littoral Habitats In A Neotropical Morichal Stream In Venezuela, Carmen G. Montaña, Craig A. Layman, Donald C. Taphorn Dec 2008

Comparison Of Fish Assemblages In Two Littoral Habitats In A Neotropical Morichal Stream In Venezuela, Carmen G. Montaña, Craig A. Layman, Donald C. Taphorn

Department of Biological Sciences

Morichales are lowland streams in South American savannas with riparian forest dominated by the moriche palm (Mauritia flexuosa). We sampled littoral habitats from ten flooded vegetated patches (dominated by Mauritiella aculeate) and six sand banks in two months of the dry season (Feb-Mar 2005) in a stream in the savannas of Apure State, Venezuela. We collected samples that compromised 12,407 individual fishes of 107 species. Small-bodied fishes (< 100 mm), representing diverse trophic and life history strategies, were abundant. The most abundant species were in the families Characidae and Cichlidae. Fish assemblages from flooded vegetated patches differed significantly from those on adjacent sand banks. High structural complexity along vegetated shoreline habitats of morichal streams likely contributes to species richness and affects assemblage composition.


"Absolutely Part Of What We Should Be Doing": Kevin Curry, Water Filters And The International Mission Of The Modern University, Andrew C. Holman Dec 2008

"Absolutely Part Of What We Should Be Doing": Kevin Curry, Water Filters And The International Mission Of The Modern University, Andrew C. Holman

Bridgewater Review

No abstract provided.


Distribution Patterns Of Sciurus Niger (Eastern Fox Squirrel) Leaf Nests Within Woodlots Across A Suburban/Urban Landscape, Carmen M. Salsbury Dec 2008

Distribution Patterns Of Sciurus Niger (Eastern Fox Squirrel) Leaf Nests Within Woodlots Across A Suburban/Urban Landscape, Carmen M. Salsbury

Scholarship and Professional Work - LAS

To determine habitat characteristics that influence Sciurus niger (Eastern Fox Squirrel) abundance and distribution within a suburban/urban landscape in the midwestern United States, I documented the density and placement of fox squirrel leaf nests in 20 woodlots in the Indianapolis metropolitan area, Marion County, IN. The woodlots varied in size (0.94 to 19.5 ha), approximate age, shape, and degree of isolation from other woodlots and suitable squirrel habitat in the surrounding area. Only 8.0% of nests were located in a tree with another nest, and nests were randomly distributed in all but one woodlot, where they were uniformly dispersed. Nest …


Biological Responses In A Dynamic Bouyant River Plume, Mark A. Moline, Thomas K. Frazer, Robert Chant, Scott Glenn, Charles A. Jacoby, John R. Reinfelder, Jennifer Yost, Meng Zhou, Oscar Schofield Dec 2008

Biological Responses In A Dynamic Bouyant River Plume, Mark A. Moline, Thomas K. Frazer, Robert Chant, Scott Glenn, Charles A. Jacoby, John R. Reinfelder, Jennifer Yost, Meng Zhou, Oscar Schofield

Biological Sciences

Buoyant river plumes are highly dynamic and often characterized by marked physical and chemical gradients that interact to drive biological responses. For example, interactions among factors resulting in algal growth (e.g., nutrient and light availability) and algal loss (e.g., sinking and zooplankton grazing) vary with spatiotemporal changes in physics and chemistry. The nature of these interactions profoundly influences the transfer and transformation of materials carried by the plume, including nutrients and metals. In April 2005, during the Lagrangian Transport and Transformation Experiment (LaTTE), water from the Hudson River recirculated in a nearshore eddy before moving southward to mix with relatively …


Dispersal Of The Hudson River Plume In The New York Bight: Synthesis Of Observational And Numerical Studies During Latte, Robert J. Chant, John Wilkin, Weifeng Zhang, Byoung-Ju Choi, Eli Hunter, Renato Castelao, Scott Glenn, Joe Jurisa, Oscar Schofield, Robert Houghton, Josh Kohut, Thomas K. Frazer, Mark A. Moline Dec 2008

Dispersal Of The Hudson River Plume In The New York Bight: Synthesis Of Observational And Numerical Studies During Latte, Robert J. Chant, John Wilkin, Weifeng Zhang, Byoung-Ju Choi, Eli Hunter, Renato Castelao, Scott Glenn, Joe Jurisa, Oscar Schofield, Robert Houghton, Josh Kohut, Thomas K. Frazer, Mark A. Moline

Biological Sciences

Observations and modeling during the Lagrangian Transport and Transformation Experiment (LaTTE) characterized the variability of the Hudson River discharge and identified several freshwater transport pathways that lead to cross-shelf mixing of the Hudson plume. The plume’s variability is comprised of several different outflow configurations that are related to wind forcing, river discharge, and shelf circulation. The modes are characterized by coastal current formation and unsteady bulge recirculation. Coastal currents are favored during low-discharge conditions and downwelling winds, and represent a rapid downshelf transport pathway. Bulge formation is favored during high-discharge conditions and upwelling winds. The bulge is characterized by clockwise …


Dietary Exposure To 2,2´,4,4´-Tetrabromodiphenyl Ether (Pbde-47) Alters Thyroid Status And Thyroid Hormone–Regulated Gene Transcription In The Pituitary And Brain, Sean C. Lema, Jon T. Dickey, Irvin R. Schultz, Penny Swanson Dec 2008

Dietary Exposure To 2,2´,4,4´-Tetrabromodiphenyl Ether (Pbde-47) Alters Thyroid Status And Thyroid Hormone–Regulated Gene Transcription In The Pituitary And Brain, Sean C. Lema, Jon T. Dickey, Irvin R. Schultz, Penny Swanson

Biological Sciences

No abstract provided.


Bio Buzz Newsletter, Issue 2, December 2008, Department Of Biology Dec 2008

Bio Buzz Newsletter, Issue 2, December 2008, Department Of Biology

Biology Buzz Newsletter

Denison University Biology Department newsletter for 2008


Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo Dec 2008

Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Integrating Development And Evolution In Psychology: Looking Back, Moving Forward, David S. Moore Dec 2008

Integrating Development And Evolution In Psychology: Looking Back, Moving Forward, David S. Moore

Pitzer Faculty Publications and Research

This work is the editorial for a special edition of New Ideas in Psychology titled Integrating Development and Evolution in Psychology.


Optimality In A Partitioned Task Performed By Social Insects, Jerome J. Howard Dec 2008

Optimality In A Partitioned Task Performed By Social Insects, Jerome J. Howard

Biological Sciences Faculty Publications

Biologists have long been aware that adaptations should not be analysed in isolation from the function of the whole organism. Here, we address the equivalent issue at the scale of a social insect colony: the optimality of component behaviours in a partitioned sequence of tasks. In colonies of Atta colombica, a leaf-cutting ant, harvested leaf tissue is passed from foragers to nest workers that distribute, clean, shred and implant the tissue in fungal gardens. In four laboratory colonies of A. colombica, we found that the highest colony-wide rate of leaf tissue processing in the nest was achieved when leaf fragment …


The Role Of Causal Processes In The Neutral And Nearly Neutral Theories, Michael R. Dietrich, Roberta L. Millstein Dec 2008

The Role Of Causal Processes In The Neutral And Nearly Neutral Theories, Michael R. Dietrich, Roberta L. Millstein

Dartmouth Scholarship

The neutral and nearly neutral theories of molecular evolution are sometimes characterized as theories about drift alone, where drift is described solely as an outcome, rather than a process. We argue, however, that both selection and drift, as causal processes, are integral parts of both theories. However, the nearly neutral theory explicitly recognizes alleles and/or molecular substitutions that, while engaging in weakly selected causal processes, exhibit outcomes thought to be characteristic of random drift. A narrow focus on outcomes obscures the significant role of weakly selected causal processes in the nearly neutral theory.


A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila, Meghana Tare, Amit Singh Dec 2008

A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila, Meghana Tare, Amit Singh

Biology Faculty Publications

The fast-changing scenario of undergraduate education puts emphasis on introducing students to hands-on techniques as part of their laboratory courses. In order to cater to large numbers of students and the time constraints involved with undergraduate level laboratory courses, there is a need for development of experiments that are cost effective and can be completed in a defined time frame. We have devised a laboratory exercise for teaching cell biology using the Drosophila melanogaster model. Drosophila can be reared in a short period of time in a cost effective manner. We used Drosophila tissue to study the sub-cellular organization of …


Preliminary Analysis Of The Ecology And Geography Of The Asian Nuthatches (Aves: Sittidae), Shaily Menon, Zafar-Ul Islam, Jorge Soberon, A. Townsend Peterson Dec 2008

Preliminary Analysis Of The Ecology And Geography Of The Asian Nuthatches (Aves: Sittidae), Shaily Menon, Zafar-Ul Islam, Jorge Soberon, A. Townsend Peterson

Peer Reviewed Publications

We explored distributions of Asian nuthatch species in ecological and geographic space using ecological niche modeling based on occurrence data associated with specimens and observations. Nuthatches represent a well-defined clade occurring throughout the Northern Hemisphere, but are most diverse in southern Asia where 15 of the 24 species occur and where the lineage is believed to have evolved. Species richness was focused in a narrow east-west band corresponding to the forested parts of the Himalayas with a maximum number of nine species predicted present in these foci. The distributional predictions have a mid-elevation focus with highest species diversity between 1,000 …


The Role Of Msa In The Global Regulation Of Virulence In Staphylococcus Aureus, Vijayaraj Nagarajan Dec 2008

The Role Of Msa In The Global Regulation Of Virulence In Staphylococcus Aureus, Vijayaraj Nagarajan

Dissertations

Staphylococcus aureus is an important pathogen causing life threatening diseases in humans. Previously we showed that msa modulates the activity of sarA (Staphylococcal accessory regulator), which is one of a major global regulator of virulence in S. aureus. The objective of this study is to characterize the role of msa (Modulator of SarA) in the global regulation of virulence in S. aureus. Structure and function predictions were done using several computational tools and approaches to understand the nature of msa. A novel S. aureus microarray meta-database (SAMMD) was designed and developed to compare and contrast other transcriptomes with msa transcriptome. …


Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann Dec 2008

Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann

Biology Faculty Publications

Here we undertook to identify colonization and gastric disease-promoting factors of the human gastric pathogen Helicobacter pylori as genes that were induced in response to the stomach environment. Using recombination-based in vivo expression technology (RIVET), we identified six promoters induced in the host compared to laboratory conditions. Three of these promoters, designated Pivi10, Pivi66, and Pivi77, regulate genes that H. pylori may use to interact with other microbes or the host. Pivi10 likely regulates the mobA, mobB, and mobD genes, which have potential roles in horizontal gene transfer through plasmid mobilization. Pivi66 occurs in the cytotoxin-associated gene pathogenicity island, a …


Investigating The Oligomerization Of Vitronectin, Yacynth Ruwansara Dec 2008

Investigating The Oligomerization Of Vitronectin, Yacynth Ruwansara

Masters Theses

Vitronectin is a multi-functional glycoprotein that is present in the plasma and extra-cellular matrix of eukaryotes. It is capable of binding a wide variety of structurally different ligands, including plasminogen activators, plasminogen activator-inhibitors, proteases, cell surface receptors and components of the extra-cellular matrix. Vitronectin exists in two conformations – as a monomer in circulation, and as a multimer in the extracellular matrix. The pathway by which vitronectin undergoes the transition from monomer to multimer is not well characterized, but this laboratory has put forward evidence to suggest that the binding of vitronectin with plasminogen activator inhibitor type-1 (PAI-1), facilitates higher …