Microbiology Commons^™

Characterization Of Manganese-Induced Neurodegenration In C. Elegans Treated With Winterberry Leaf Extract, Brendan Moline

Honors College

Neurodegeneration is a condition present in Alzheimer’s disease (AD) and Parkinson’s disease (PD) in which the cells of the nervous system experience loss of function and death. Around the world, each year PD and AD affect 6.2 million and 29.8 million people, respectively, with the exact causes remaining unknown. Manganese (Mn) is a transition metal which is essential for human survival in trace concentrations. However, overexposure to Mn can induce neurodegeneration through the accumulation of reactive oxygen species and the eventual onset of oxidative stress. An extract produced from winterberry leaves (Ilex verticillata) exhibits antioxidant properties as it has been …

Evaluating Edna Metabarcoding As A Mic-Roe-Scopic Net To Catch Salmon Pathogens, Noah Burby

Honors College

Wild Atlantic salmon in the Gulf of Maine (GOM) is a Distinct Population Segment (DPS) that has been listed since 2000 as endangered by the U.S. Fish and Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration (NOAA). The current challenge is year-over-year decreases in the number of mature salmon returning to the Penobscot River for reproduction. Early detection of pathogen presence could allow for the identification of infection and the application of corrective measures. Environmental DNA (eDNA) is simply DNA that is collected from environmental samples (e.g., water, air, and soils), which consists of whole microorganisms and genetic …

Many Questions Remain Unanswered About The Role Of Microbial Transmission In Epizootic Shell Disease In American Lobsters (Homarus Americanus), A Perspective Article, Suzanne Ishaq, Sarah M. Turner, M. Scarlett Tudor, Jean Macrae, Heather Hamlin, Joelle Kilchenmann, Grace Lee, Deborah A. Bouchard

Journal Articles

Despite decades of research on lobster species’ biology, ecology, and microbiology, there are still unresolved questions about the microbial communities which associate in or on lobsters under healthy or diseased states, microbial acquisition, as well as microbial transmission between lobsters and between lobsters and their environment. There is an untapped opportunity for metagenomics, metatranscriptomics, and metabolomics to be added to the existing wealth of knowledge to more precisely track disease transmission, etiology, and host-microbe dynamics. Moreover, we need to gain this knowledge of wild lobster microbiomes before climate change alters environmental and host-microbial communities more than it likely already has, …

Impact Of Probiotics On Black Soldier Fly Larvae Transmission Of Stenotrophomonas Maltophilia, Emily Marie Mclaughlin

Honors College

Stenotrophomonas maltophilia is an opportunistic pathogen which can cause a variety of infections, especially in immunocompromised individuals. It has recently been found that black soldier flies can act as carriers for S. maltophilia (Callegari et al., 2020). I have investigated how probiotics impact their vector capabilities. Black soldier fly larvae have been fed substrate spiked with S. maltophilia. After several days of feeding, the larvae were investigated by PCR and plating (Sveensson-Stadler et al., 2011). Two groups of larvae were fed with potatoes infected with S. maltophilia. Persistence of S. maltophilia was determined using PCR by taking samples …

Understanding The Role Of Prophage Encoded Polymorphic Toxins In Mycobacterial Superinfection Immunity And Drug Resistance, Dakota Archambault

Honors College

Mycobacterium abscessusis the leading cause of lung infection in cystic fibrosis patients and is often resistant to all antibiotics. There is an urgent need for alternative therapies such as lytic bacteriophage (viruses that infect bacteria). Phage therapy has been successful in the treatment of a drug-resistantM. abscessusinfection in a teenaged cystic fibrosis patient but there are challenges to broad use as most M. abscessusisolates are highly resistant to lytic bacteriophage infection. Prophage, or integrated bacteriophage genomes within the M. abscessusgenome, likely defend against phage superinfection via prophage-encoded viral defense systems. The Molloy lab has shown that the Mab cluster R …

An Investigation Of The Relationship Between Black Soldier Fly Larvae Pathogen Suppression And Growth Substrate In Relation To Maine Agricultural Industries, Haley Morrill

Honors College

Insects are promoted as cost-effective and sustainable protein sources for animal feed. Their utilization may help to avoid a predicted global protein shortage. Black soldier fly (Hermetia illucens) larvae (BSFL) grow on organic wastes, converting these wastes into larval biomass which can fulfill this purpose. Potential benefits of using BSFL to remediate organic wastes include reduction of waste mass and bacterial load, along with the sale of larvae as a protein supplement. BSFL suppress the growth of some Gram-positive and Gram-negative human pathogens in these substrates; though suppression of Bacillus cereus, a spore-forming bacterium that causes food-poisoning, …

Infection And Diet-Induced Gut Dysbiosis: Impact On Sleep Quality In Danio Rerio, Benjamin Williams

Honors College

A known bidirectional relationship between intestinal microflora and the central nervous system, coined the gut-brain-axis, has stimulated work on the association between gut dysbiosis and inflammation, and sleep quality. Previous studies in the Hayes Lab have reported that a high fat (HF) diet was correlated with immobile phases, a marker of low motility during sleep found in some neurological disease and sleep duration[1]. Long sleep duration (>1 S.D. above norms for age) is associated with poor sleep quality or sleep fragmentation in participants who are overweight or obese according to body mass index values[2]. The current work utilizes a …

Characterizing The Diversity Of Cluster R Prophage In Mycobacterium Abscessus, Colin Welch

Honors College

Mycobacterium abscessus is a mycobacterial pathogen responsible for pulmonary and disseminated infections in susceptible individuals and often is resistant to all antibiotic therapies, with cure rates ranging from 25% to 58% (Degiacomi et al., 2019).Investigating the mechanisms of extensive resistance in M. abscessus lends opportunities to develop more effective treatments. Prophage, viral sequences integrated into bacterial genomes, contribute to virulence and fitness in many bacterial pathogens including Escherichia coli O157:H7 and Vibrio cholerae (Fortier & Sekulovic, 2013). Yet, prophage in pathogenic mycobacteria are not well understood or studied. Recent work has demonstrated that the Mycobacterium chelonae prophage, McProf can function …

The Role Of Accessory Domain In Cpsa Function And Capsule Production In Group B Streptococcus, Gina Difederico

Honors College

Group B Streptococcus (GBS) can be found in the vaginal and genitourinary tract of females, as well as the genitourinary tract of males, where it behaves as a commensal organism. However, as an opportunistic pathogen, GBS has the capability to infect the immunocompromised, making it a major threat to neonates and fetuses. The pathogen can be passed from mother to baby either in utero or during birth. The capsule, which is a polysaccharide coating on the outside of the cell, is considered the most important virulence factor in GBS.Expression of capsule plays a role in evasion of the host immune …

Framing The Discussion Of Microorganisms As A Facet Of Social Equity In Human Health, Suzanne L. Ishaq, Maurisa Rapp, Risa Byerly, Loretta S. Mcclellan, Maya R. O'Boyle, Anika Nykanen, Patrick J. Fuller, Calvin Aas, June M. Stone, Sean Killpatrick, Manami M. Uptegrove, Alex Vischer, Hannah Wolf, Fiona Smallman, Houston Eymann, Simon Narode, Ellee Stapleton, Camille C. Cioffi, Hannah F. Tavalire

Animal and Veterinary Sciences Faculty Scholarship

What do “microbes” have to do with social equity? These microorganisms are integral to our health, that of our natural environment, and even the “health” of the environments we build. The loss, gain, and retention of microorganisms—their flow between humans and the environment—can greatly impact our health. It is well-known that inequalities in access to perinatal care, healthy foods, quality housing, and the natural environment can create and arise from social inequality. Here, we focus on the argument that access to beneficial microorganisms is a facet of public health, and health inequality may be compounded by inequitable microbial exposure.

Examining The Microbiome Of Porphyra Umbilicalis In The North Atlantic, Margaret Aydlett

Honors College

Marine macroalgae host a diverse microbiota. Bacteria are the most prominent group, and relationships between the algae and bacteria are complex and dynamic. The goal of this project was to examine the distribution and ASV diversity of Bacteria associated with Porphyra umbilicalis with special focus on some isolates, including studies of their temperature dependence and consideration of how they may affect Porphyra. Previous studies showed that some bacteria are required for normal algal morphology and growth. Porphyra umbilicalis is an abundant red macroalga found in the intertidal zone and is an important food for invertebrates. Because of its significance in …

Determining Key Residues Of The Lyt-R Domain In The Streptococcal Cpsa Protein, Mohammad Hashmi

Honors College

Streptococcus agalactiae or Group B Streptococcus (GBS), is a Gram-positive commensal bacterium that is harmless in healthy adults, yet causes systemic diseases in neonates, the elderly, and immunocompromised individuals. Neonates are at risk of GBS infection in utero or during delivery due to the colonization of the organism in the vaginal canal of between 15-30% of adult females. GBS can cause severe neonatal sepsis and meningitis, as well as chorioamnionitis, which can cause premature birth and stillbirth. GBS infection is greatly facilitated by the presence of a bacterial capsule; a protective, polysaccharide matrix surrounding the cell that plays a key …

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 …

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 …

Summary Report Of Enhanced Monitoring And Pollution Source Tracking Efforts In The Willard Beach Watershed, Maine, 2012-2016, M. Sims, K. Kaczor

Maine Sea Grant Publications

Willard Beach is a popular recreation area located in South Portland used primarily by families with young children. Routine monitoring at the beach revealed elevated bacteria levels, prompting the need for enhanced monitoring within the watershed to determine the nature and extent of potential bacteria inputs. Although the waste of domestic and wild animals can contribute to impaired water quality and pose a public health risk, efforts have focused primarily on identifying and removing human sources (e.g. malfunctioning septic systems, faulty sewer lines) of fecal pollution.

Maine Healthy Beaches Program 2016 Annual Report To U.S. Epa, K. Kaczor, M. Sims

Maine Sea Grant Publications

Maine Healthy Beaches (MHB) is managed by the Maine Department of Environmental Protection (ME DEP) and coordinated by the University of Maine Cooperative Extension (UMaine Extension). In 2016, this team worked with 28 local management entities to conduct routine monitoring, assessment, and public notification of water quality conditions for 60 beach management areas spanning Kittery to Mount Desert Island. MHB staff continued to build local capacity for well-informed beach management and to address pollution issues when they arose during the beach season.

Summary Report Of Enhanced Monitoring And Pollution Source Tracking Efforts In Goosefare Brook, Maine, 2012-2016, M. Sims, K. Kaczor

Maine Sea Grant Publications

The Goosefare Brook (GFB) forms the border between the City of Saco to the south and Town of Old Orchard Beach (OOB) to the north. In response to concerns over water quality in the mouth and adjacent beach water, the Maine Healthy Beaches (MHB) program has supported multi-year enhanced monitoring and pollution source tracking efforts, held Stakeholder Workshops, and more to address impaired water quality throughout the watershed. Over the past five years, the MHB program has focused primarily on paired enterococci and optical brightener samples in OOB’s New Salt Rd. Tributary (NSRT). This work identified widespread bacterial contamination throughout …

Maine Healthy Beaches Program Excerpts From Data Analysis, 2006-2015, K. Kaczor, M. Sims

Maine Sea Grant Publications

No abstract provided.

Characterizing The Intact Prophage Of Mycobacterium Chelonae Bergey, Erica Sewell

Honors College

Mycobacteriophage (phage), are viruses that infect bacteria. All bacteria can be

infected by phage, and each bacterial species has a unique set of phage that infect them, making phage prime candidates for studying viral diversity and evolution. Some phage integrate their genome into the host genome upon infection (prophage), where they may potentially remain indefinitely, coevolving with the host, and providing growth factors and other benefits to the host. The purpose of my research is to characterize a prophage within the genome of the bacterial host Mycobacterium chelonae Bergey to determine if it is still functional and potentially impacting the …

Best Practices For Healthy Beaches And Watersheds In Maine: Potential Bioremediation Strategies For Improving Water Quality, Elyse Defranco

Maine Sea Grant Publications

Maine’s watersheds face many challenges from human inputs, with pollution threatening the health of our beaches, rivers, and aquaculture operations. Maine’s rural communities often lack the resources to update aging sewer infrastructure or to adequately maintain septic systems, and these sources of pollution impact watershed health. In addition to addressing sources of pollution, which can be difficult to ascertain and challenging to address when located, bioremediation practices have the potential to aid in clean-up efforts. New technological advances and research discoveries in creative forms of bioremediation are being developed and are producing promising case studies around the world. These new …

2016 Goosefare Brook Mst Summary And Next Steps, M. Sims, K. Kaczor

Maine Sea Grant Publications

No abstract provided.

Jordan River Monitoring Report, Ashley Taylor, Anna Farrell

Maine Sea Grant Publications

In congruence with the Maine Department of Marine Resources’ (DMR) efforts to monitor declining water quality in the Jordan River, Frenchman Bay, Maine, the Community Lab at MDI Biological Laboratory implemented regular water quality monitoring at additional sites in the watershed to supplement the work of the DMR. Water samples were collected weekly between June and August of 2017 by staff and students from the Community Lab. Samples were collected via boat and foot to reach additional intermittent streams and smaller tributaries that feed into the Jordan River. Samples were analyzed for Enterococcus bacteria, optical brighteners, and salinity. A goal …

Innate Immune Recognition Of Candida Albicans In Zebrafish, Monique Elaine Theriault

Honors College

Candida albicans is an opportunistic fungal pathogen that has the capability to switch from commensal to pathogen in immunocompromised individuals. Recognition of pathogens, like C. albicans, during infection is poorly characterized primarily due to the difficulties in visualizing the host/pathogen interaction without killing the host. Transparent animal hosts, such as Danio rerio (zebrafish), enable imaging of pathogen recognition while maintaining host viability. For pathogen recognition, zebrafish likely use immune receptors similar to mammalian receptors including C-type lectin receptors. Human C-type lectin receptors have already been shown to be crucial in recognition of fungal pathogens like C. albicans, and our goal …

Characterizing The Neutrophil Response To Influenza A Virus Infection In The Zebrafish Model, Alexis Rae Bowman

Honors College

Neutrophils are a type of innate immune cell that play a critical role in the acute inflammatory response by recognizing, phagocytizing and killing pathogens. Although their presence during infection is immensely significant for pathogen clearance, current research suggests that an overly robust neutrophil response may be detrimental to the host. Expression levels of the zebrafish chemokines Cxcl8-l1 and Cxcl8-l2, which are responsible for inducing neutrophil migration to a site of infection, have been shown to increase under inflammatory conditions caused by various PAMPs and infectious stimuli. Cxcl8 expression levels under inflammatory conditions caused by human viral infections, such as Influenza …

Is The Ubiquitous Antibacterial Agent Triclosan An Uncoupler Of Mammalian Mitochondria, Hina Hashmi

Honors College

Triclosan (TCS), an antibacterial agent widely found in household and clinical products, is readily absorbed into human skin, but TCS effects on mammalian cells are largely unknown. TCS has been found to alleviate symptoms of human eczema, via an unknown mechanism. Mast cells are ubiquitous, key players in allergy, infectious disease, carcinogenesis, autism, and many other diseases and physiological functions. One important function of mast cells is release of pro-inflammatory mediators from intracellular granules (degranulation) upon challenge with antigen. Non-cytotoxic doses of TCS inhibit several functions of both human (HMC-1.2) and rat (RBL-2H3) mast cells, including degranulation. Previous work in …

Urbanization Changes The Composition And Bioavailability Of Dissolved Organic Matter In Headwater Streams, Thomas B. Parr, Christopher Cronan, Tsutomu Ohno, Stuart Findlay, Sean Smith, Kevin Simon

Publications

Population growth in cities has resulted in the rapid expansion of urbanized land. Most research and management of stream ecosystems affected by urban expansion has focused on the maintenance and restoration of biotic communities rather than their basal resources. We examined the potential for urbanization to induce bottom-up ecosystem effects by looking at its influence on dissolved organic matter (DOM) composition and bioavailability and microbial enzyme activity. We selected 113 headwater streams across a gradient of urbanization in central and southern Maine and used elemental and optical analyses, including parallel factor analysis of excitation-emission matrices, to characterize DOM composition. Results …

Functional Role Of Zebrafish Tlr Proteins, Carol H. Kim

University of Maine Office of Research Administration: Grant Reports

Project summary.

Influenza virus infections lead to significant illness, mortality, and social disruption worldwide. Herein, the first studies establishing the zebrafish as a model for human influenza infection are presented and it is shown that influenza infection proceeds and can be resolved through similar mechanisms in zebrafish and humans (Gabor, et al.). Our laboratory has previously characterized a fish rhabdovirus infection model in the zebrafish (Phelan, et al.).

Comparafac: A Library And Tools For Rapid And Quantitative Comparison Of Dissolved Organic Matter Components Resolved By Parallel Factor Analysis., Thomas B. Parr, Tsutomu Ohno, Kevin Simon

Publications

Parallel Factor Analysis (PARAFAC) is a well-established method for characterizing dissolved organic matter (DOM). While methods for sample processing and PARAFAC analysis are well defined and robust, subsequent classification of DOM fluorescence components and comparisons of components among studies remain highly qualitative. Because these comparisons often guide the interpretation of subsequent data, it is important that quantitatively accurate comparisons be made. We developed a statistical tool, comPARAFAC, using a modified Tucker’s Congruence Coefficient (mTCC), an established method of factor comparison, to provide a quantitative basis for comparing models. To develop and test this tool we used mTCC to compare factors …

Evolutionary And Molecular Analysis Of Conserved Vertebrate Immunity To Fungi, Erin Carter

Honors College

The innate immune system is highly conserved amongst all multicellular organisms. Yet a constant battle exists between host cells and pathogens due to the rapid evolution of immune system components. Functional genomics and in silico methods can be employed to elucidate the evolutionary patterns of vertebrate immunity to pathogenic fungi such as Candida albicans, an opportunistic fungal pathogen that can cause lethal candidiasis in the immunocompromised. Mammals such as humans and mice possess conserved C-type lectin receptors that recognize the C. albicans cell wall. However, these receptors have not been identified in fish. Here I describe how we identified potential …

Unmasking Candidiasis: A Mechanistic Model For Innate Immune-Fungal Cell Wall Dynamics, Erica Hidu

Honors College

Candida albicans is an opportunistic fungal pathogen that can cause a potentially lethal systemic infection in immunocompromised patients. Increasing drug resistance of Candida species to anti-fungal treatments makes the study of this pathogen ever more important. Study of the C. albicans cell wall provides insight into its importance in pathogenesis, immune recognition, and anti-fungal action. It has been shown that β- glucan, a masked component of the fungal cell wall and ligand for the immune receptor Dectin-1, becomes available for immune recognition in the mouse model of systemic candidiasis. To develop a mechanistic model to explain this unmasking, we investigated …