Microbiology Commons^™

The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii

Electronic Theses and Dissertations

Sulfide minerals oxidize through interaction with water and oxygen, releasing hydrogen ions. The process often occurs naturally near metal sulfide deposits, and can be accelerated through mining. Microorganisms accelerate the rate of sulfide oxidation. Acidified streams typically contain high metal concentrations (e.g. aluminum) and microbes in these systems may develop resistances to metal toxicity. Stream flow can affect sulfide oxidation and microbial community structure. Baseflow can influence stream chemistry from interactions with the surrounding bedrock, while stormflow affects stream chemistry and the local microbial community through dilution and addition of microbes transported by runoff. Microbial community composition is affected by …

Host Mediated Mechanisms Of Fungal Cell Spread In A Transparent Zebrafish Infection Model, Allison Scherer

Electronic Theses and Dissertations

Innate immunity has developed elegant processes for the detection and clearance of invasive fungal pathogens. Disseminated candidiasis is of significant concern for those with suppressed immune systems or indwelling medical equipment, and mortality in these groups approaches 70%. Poor patient outcomes have spurred the need to understand how this non-motile pathogen spreads in the host. Technical limitations have previously hindered our ability to visualize the role of innate immunity and host tissue barriers in the spread of C. albicans in vivo. Using the zebrafish model to overcome these limitations, we have examined three potential host-mediated mechanisms of dissemination: movement …

Thermal And Microbial Effects On Brown Macroalgae: Heat Acclimation And The Biodiversity Of The Microbiome, Charlotte Tc Quigley

Electronic Theses and Dissertations

This dissertation examines effects of stress on brown algal biology from a macroscopic scale by examining the whole aquaculture crops, and at a microscopic level by examining the macroalgal microbiome, across the vertical stress gradient of the intertidal zone and across the latitudes of their biogeographic ranges. Thermal stress negatively affected seedstock gametophytes of the kelp Alaria esculenta isolated from northern and southern locations in Maine. However, previous thermal stress had a positive effect on growth of the next-generation sporophytes. Alaria esculenta has potential as a kelp crop in Maine’s sea vegetable aquaculture sector and implementing this protocol may allow …

Investigating Present-Day Health Issues Of The American Lobster (Homarus Americanus), Deborah A. Bouchard

Electronic Theses and Dissertations

The American lobster, Homarus americanus, H. Milne Edwards, 1837, supports the most economically valuable fishery along the North Atlantic coast of North America. A collapse in lobster populations in Southern New England (SNE) has coincided with increasing ocean temperatures and emerging diseases. This research investigated the etiologies of limp lobster disease (LLD) and epizootic shell disease (ESD), two diseases that continue to cause significant mortality in natural lobster populations. Mortality from LLD is associated with the bacteria Photobacterium indicum and is more intense in impounded lobsters. To more clearly define the community ecology of this suspected opportunistic pathogen, the microbial …

Identification Of Tnfaip8l1 Binding Partners Through Co-Immunoprecipitation And Mass Spectrometry, Audrey Hoyle

Honors College

The expanded understanding of the gene families and mechanisms governing tumorigenesis pathways has enormous potential for improving current cancer therapies and patient prognoses. One such gene family that participates in the regulation of tumorigenesis is the tumor necrosis factor alpha-induced protein 8 (TNFAIP8) gene family, which is comprised of four members: TNFAIP8, TNFAIP8L1, TNFAIP8L2, and TNFAIP8L3. The TNFAIP8L1 gene is thought to function as a tumor suppressor, but the mechanisms by which it exerts this function have yet to be elucidated. We hypothesize that the TNFAIP8L1 protein acts as a tumor suppressor through protein-protein …

Reducing Tillage In Small-Scale Permanent Bed Organic Vegetable Production Systems, Jeremiah D. Vallotton

Electronic Theses and Dissertations

The response of field-grown vegetable crops to reduced tillage and mulching in permanent beds was evaluated through measuring crop yields, weed pressure, earthworm counts, and soil basal respiration. Two vegetable crops (“Bush Delicata” squash and “Farao” cabbage) were started in April and May of 2016 and 2017 respectively, transplanted in late June, and harvested on 15-Sep-2016 and 25-Aug-2017. Fruit number and weight of squash, and head weight and feeding damage of cabbage were measured. These results suggest that intensive tillage (8” rototill every year) can be successfully reduced to alternating years of shallow (2”) rototilling and a less intensive form …

Determining The Role Of Saly In Streptococcus Pyogenes Immune Evasion Using Fluorescence Microscopy, Taaniel Kiidli

Honors College

Streptococcus pyogenes, the etiologic agent for several life-threatening invasive diseases, utilizes numerous mechanisms to evade the host immune response and establish a successful infection causing a significant source of morbidity and mortality risks for patients. The bacterium is known to cause necrotizing fasciitis in both humans and zebrafish, with extensive necrotic damage to tissues but surprisingly lacking in an inflammatory response for a systemic infection. This suggests that the recruitment of inflammatory cells to the site of infection is inhibited. To observe this in real-time, we used the zebrafish model of Streptococcal pathogenesis to analyze immune cell recruitment in …

Hitchner (E. Reeve) Records, 1915-1969, Special Collections, Raymond H. Fogler Library, University Of Maine

Finding Aids

These records contain textual information created by and about E. Reeve Hitchner during his tenure at University of Maine, Orono, as Professor of Bacteriology (1922-1959), Head of the Department of Bacteriology (1932-1958), and overseeing the Pullorum-Typhoid Testing Service at the University of Maine until his retirement in 1958.

Include biographic information regarding Hitchner, copies of his thesis, papers, and notebooks, various correspondence on a range of subjects, details regarding the Orono Town budget (1965 & 1967), class notes, research cards, and reports related to Hitchner's research particularly on water and air pollution, but also: wood rot, pickles, Pullorum Disease, mining …