Academic Research

Dr. Jennifer Brofft Bailey studies specific Bacteria/Archaea that are capable of nitrate assimilation, urea assimilation and ammonia oxidation in marine, freshwater and soil systems. Dr. Jennifer Zettler investigates the ecological effects of red imported fire ants on native invertebrates and plants. Together, both researchers are determining if fire ant mounds serve as “hot spots” for nitrification since they are enriched with oxygen and ammonia, conditions which should favor the growth of ammonia oxidizing Bacteria and Archaea.

Dr. Kathryn Craven is a marine biologist focused on endangered and protected species. Research interests include work with sea turtle nest success and population dynamics in diamondback terrapins. Currently, Dr. Craven is investigating the influence of environmental microbes on Loggerhead Sea Turtle eggs in collaboration with Dr. Brofft-Bailey at Armstrong and the Caretta Research Project on Wassaw Island.

Dr. Sara Gremillion - The fungi are an ecologically, economically, and medically important group of organisms.  Dr. Gremillion is interested in highlighting the cellular components involved in filamentous fungal polarization using the model fungus Aspergillus nidulans.  Mutations in two protein subunits of the Conserved Oligomeric Golgi (COG) complex have been linked to abnormal fungal growth.  Dr. Gremillion and her undergraduate students are investigating the role of the eight subunits (COG1-8) in the function of the complex.

Dr. Michele Guidone investigates the ecological impacts of human alterations to marine and freshwater environments. Human influences on these habitats include: structures that form hardened shorelines, pollutants that disrupt chemical processes, invasive species that alter community diversity, and the overarching threat of global climate change. Recent projects in the Guidone lab have included investigations of: the causes, controls, and impacts of macroalgal blooms in coastal marine systems; the impacts of the invasive aquatic plant Eurasian watermilfoil on invertebrate diversity and freshwater food webs; and alterations to mud snail populations in areas invaded by the non-native alga Gracilaria vermiculophylla.

Dr. Jay Hodgson is an ecologist and has two main research interests.  Primarily, as a paleoecologist, he is interested in reconstructing historical environments and climate change by using diatom microfossils buried in sediments. Secondarily, he investigates foraging patterns by predators.

Dr. Heather Joesting researches the morphological and physiological adaptations to abiotic stress (such as high incident sunlight, salt spray, and sand burial) for coastal sand dune plant species. Dr. Joesting is currently working with several undergraduate researchers on the autecology of the clonal sand dune herb Hydrocotyle bonariensis. Specifically, research is focused on determining the role of vertical leaf inclination in maintaining daily leaf carbon gain, examining phenotypic variation within individuals located in different habitats, and investigating the viability of field-produced seeds and the contribution of sexual reproduction to the population structure of this plant species.

Dr. Brett Larson with Dr. Alex Collier - The effect of potential kairomones released by predators or alarm cues released by prey on larval tadpole development by measuring the length and weight of tadpoles exposed to predator fish or not and with or without being able to see the predator.

Dr. Melanie Link-Perez investigates the diversification and evolutionary relationships of seed-free vascular plants (ferns and lycophytes).  Currently, Dr. Link-Perez and several undergraduate researchers are describing new species in the neotropical fern genus Adiantopsis and exploring the role of hybridization and polploidy in this group using nuclear DNA data and molecular cloning.

Dr. Scott Mateer - Biocatalysis is the use of microbes or their enzymes to generate chiral specific organic compounds that can be used as the building blocks for pharmaceuticals such as Prozac™. In short, biocatalysis is the use of little bugs to make big drugs. The ability of enzymes to generate these stereospecific molecules is not clearly understood. Dr. Scott Mateer, in collaboration with Dr. Brent Feske and Dr. Cliff Padgett, are trying to understand the molecular mechanisms that regulate an enzyme's stereoselectivity via mutagenesis of specific yeast reductases and subsequent analysis of the mutant reductase's ability to make chiral molecules. Their work is currently being funded by an NSF-RUI grant.

Dr. Traci Ness - Identification of genes involved in sea turtle immunity.  One of the biggest challenges of research on sea turtles is that there are no commercially-available animals, cells, or turtle-specific reagents. Direct collection of samples from endangered species requires federal permits that are granted to a limited number of researchers.  The Georgia Sea Turtle Center (Jekyll Island) has collected blood samples from loggerhead sea turtles.  From the white blood cells, we are working to construct a cDNA library.  From this library, we hope to identify, clone, and sequence genes involved in sea turtle immunity.
Identification and characterization of immune receptors that recognize fungal infections in the mouth.  The oral cavity is continually exposed to a variety of microbes and patten recognition receptors (PRR,s) are responsible for discriminating between microbes and initiating an appropriate immune response.  Most PRR research focused on immune cells; it is the epithelial cells that are present at the site of initial infection that must first recognize the invaders and alert and recruit immune cells to the site of infection.  Dr. Ronald Garner (Mercer University School of Medicine) and I have begun a collaboration to investigate the recognition of the pathogenic yeast Candida albicans by PRR,s in oral epithelial cells.  The primary goal of this project is to identify the PRR repertoire of these cells and to characterize the changes that occur following stimulation with Candiala.  Ultimately, we will probe the PRR-Candida interactions that lead to the formation of signaling scaffolds on the surface of oral epithelial cells.  These studies wlll provide us with a better understanding of oral immunity and may have applications in the treatment of oral diseases including those caused be microbes and oral cancers.  We use a variety of molecular biology techniques:  DNA/RNA purification, Polymerase Chain Reaction (PCR), gel electrophoresis, mammalian cell culture, western blot, enzyme-linked immunosorbent assay (ELISA), flow cytometry, and fluorescence microscopy.

Dr. Aaron Schrey - I use molecular markers to study the role of epigenetic mechanisms in the ecology and evolution of non-model organisms, molecular ecology, and conservation genetics. I have experience with freshwater and marine fish, herpetofauna, birds, insects, mammals, and plants.
My research is focused in two areas: 1. Ecological and Evolutionary Epigenetics: I am interested in studying how epigenetic factors are important for an organism’s response to the environment, how epigenetic variation may provide an alternative source of phenotypic variation among individuals, and the role of epigenetic variation in ecology and evolution. Ecological Epigenetics is the study of heritable and non-heritable changes in gene expression and function due to factors other than alteration to DNA sequence. Some epigenetic modifications (e.g. DNA methylation) contribute to phenotypic variation and can be stably transmitted across generations. Thus, epigenetic variation may be important to ecology and evolution, and understanding its mechanistic basis will provide insights into individual- and population-level processes. Also, epigenetic mechanisms may be important in organism-environment interactions by enabling organisms to alter their phenotypes quickly in response to a changing environment. 2. Molecular Ecology and Conservation Genetics: I use highly polymorphic DNA microsatellites and next-generation DNA sequencing to study molecular ecology and conservation genetics. I am interested in contrasting species with different autecologies among dynamic environments to determine the ecological factors that generate genetic differences. I target: 1) disturbed habitats and habitats with abrupt variation, 2) the role of hybridization in evolution, 3) introduced or invasive species and species with active range expansions, and 4) conservation and management of natural resources.