Microbiology Commons^™

Characterizing The Role Of Pa5189 Of Pseudomonas Aeruginosa In Deletion And Overexpression Mutants, Seh Na Mellick

Theses/Capstones/Creative Projects

In the context of rising multidrug resistance in biofilm-forming pathogens like Pseudomonas aeruginosa, this study investigates the role of the understudied transcription factor PA5189 in antibiotic resistance and biofilm formation. PA5189 deletion and overexpression mutants were created in a parent P. aeruginosa strain using pEX18Tc-based recombinant suicide vectors, with genotypic verification of putative triparental conjugants achieved through restriction digestion and PCR. The study revealed that PA5189 overexpression significantly increases resistance to commonly used broad spectrum antibiotics such as ciprofloxacin and imipenem. Additionally, differential expression of PA5189 was found to notably affect biofilm formation, with variations contingent on the nutrient …

Investigating The Mechanisms Of Surface Sensing Using Motility Appendages By Pseudomonas Aeruginosa Pa14, Christopher James Geiger

Dartmouth College Ph.D Dissertations

Biofilms are surfaced attached communities of cells encased in an extracellular matrix. The transition from free-swimming planktonic cells to a surface attached biofilm begins with cellular changes that occur after surface contact. This process is known as "surface sensing" and the opportunistic pathogen Pseudomonas aeruginosa PA14 uses its two motility appendages, type IV pili (T4P) and a single, polar flagellum to sense and traverse surfaces. The first cellular changes to occur within this organism upon surface contact is an increase in the second messengers cAMP and cdi- GMP. While the genes involved in surface sensing by P. aeruginosa are known, …

Investigating Optimal Laboratory Growth Conditions Of Gracilibacillus Halotolerans In Media Supplemented With Salt, Isaac Young

Annual Research Symposium

As interest continues to grow in the field of persister cells and their morphology, there arises an ever-evolving desire to further understand specific strains of bacteria that exemplify the qualities of seemingly anomalous survival regardless of anti-bacterial treatment. In the case of the Gracilibacillus halotolerans, a halotolerant extremophile extracted from the Great Salt Lake with known persistent characteristics, uncovering its optimal growth conditions was essential for future investigations. Identifying the optimal salinity for the growth of G. halotolerans will allow us to standardize our growth methods, uncover several mechanisms of saline tolerance, and add to future investigations of persistence with …

Interplay Of Periodontal Bacterial Metabolites In The Progression Of Coronary Artery Disease: A System Biological Approach, Janakiraman V

Annual Research Symposium

Purpose:

The purpose of this study is to investigate the intricate relationship between periodontal disease (PD) and coronary artery disease (CAD), as evidenced by epidemiological associations. Metalloproteinase inhibitor (TIMP1) plays a pivotal role in cellular signaling, differentiation, cell death, and migration by binding to target metalloproteinases, forming complexes with other molecules (collagenases) to inactivate them. However, the expression of TIMP1 is reduced in both PD and CAD, leading to an upregulation of other metalloproteinases. This research explores the hypothesis that metabolites released from (Porphyromonas gingivalis), a prevalent bacterium in atherosclerotic patients, may inhibit TIMP1, thereby influencing CAD progression. …

College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 Noble Prize Winner Speaks on Campus
Page 6-7 Faculty Excellence
Page 8-9 Student Excellence
Page 10 Outreach Program
Page 10 Events and Traditions
Page 11 Connections Abroad
Page 12 Student Spotlight
Page 13 Alumni Spotlight
Page 14 First Ever Drone Day
Page 15 Grand Opening of POET Bioproducts Center
Page 16 Work Anniversaries

Finding Gene Candidates That Interact With Mara To Control Hila Expression In Salmonella Enterica, Kylee Hempel

Undergraduate Research Symposium

Salmonella is a well-known pathogen that is linked to food born illnesses common around the world. This pathogen can cause symptoms such as fever, diarrhea, and chills in the host. One of the mechanisms Salmonella uses to infect its host’s epithelial cells deals with the S. typhimurium pathogenicity island 1 (SPI-1). Expression of SPI-1 is activated in response to environmental signals that correlate with the ileum of the small intestine (low oxygen, high osmolarity, and neutral pH). HilA is the central activator of the SPI-1 complex, and when the transcription factor, MarA, is over-expressed in Salmonella, hilA transcription is …

A Survey Of Fusarium Oxysporum In Georgia Hemp Farms And Vegetable Gardens, Wesley Demontigny, Christopher D. Burt, Jaiden Stidston

Georgia Journal of Science

Recent changes in U.S. federal law have recognized the genetic and chemical differences between hemp and marijuana (Cannabis sativa L.), resulting in the legalization of hemp in the United States. The barriers to this plant’s growth in the state of Georgia are not well understood due to its prohibition for the past 80 years. Among the many possible obstacles is fungal disease. Fusarium oxysporum (Schlecht. emend. Snyder & Hansen) is a fungus that damages various crops and was previously researched as a biocontrol agent for C. sativa. Thus, this study surveyed hemp farms in Georgia to determine the prevalence …

Effectiveness Of Mycorrhizae And Vermicompost Seed Inoculation For Germination, Vegetative Growth, Cannabinoid Content, And Cured Flower Weight Of Cbd-Rich Hemp (Cannabis Sativa L.), Hannah Boyer, Nicole Wagner, Merritt Drewery

Journal of Agricultural Hemp Research

Effective germination and vigorous growth of hemp cultivars is paramount to cultivators’ ability to produce high-quality hemp products. Beneficial bacteria and fungi are known symbionts to plants and are used in regenerative agriculture to increase plant health and crop yield. This pilot study investigated the effect of microbial seed inoculation on germination rate, plant height, cured flower weight, and cannabinoid content of cannabidiol (CBD)-rich hemp (Cannabis sativa L). The experiment included a control and the following treatments: 1) seed inoculation of Great White ^â Premium Mycorrhizae (GW), 2) seed inoculation of vermicompost (V), and 3) seed inoculation of Great …

The Ecological Responses To Hydroperiod Of Wetland Plant Species Determined By Manipulated Soil Surface Elevation (Marsh Organs), Brandon Wolff

LSU Master's Theses

As sea level rise, subsidence, and abandonment of natural deltaic processes due to a highly engineered Mississippi River continue to threaten Louisiana’s coastal wetlands, the need for a system-wide understanding of natural wetland land-building and preservation processes has never been greater. A key component of any wetland is the ever-changing water environment that periodically floods and dries the marsh platforms. The flooding depth, duration, and frequency, known as the hydroperiod, along with salinity and soil fertility are key determining factors of vegetation and marsh types at a particular location. Different types of vegetation will have different growth characteristics such as …

Secreted Igm Modulates Il-10 Expression In B Cells, Shannon Mcgettigan, Lazaro Aira, Gaurav Kumar, Romain Ballet, Eugene Butcher, Nicole Baumgarth, Gudrun Debes

Department of Microbiology and Immunology Faculty Papers

IL-10⁺ B cells are critical for immune homeostasis and restraining immune responses in infection, cancer, and inflammation; however, the signals that govern IL-10⁺ B cell differentiation are ill-defined. Here we find that IL-10⁺ B cells expand in mice lacking secreted IgM ((s)IgM^–/–) up to 10-fold relative to wildtype (WT) among all major B cell and regulatory B cell subsets. The IL-10⁺ B cell increase is polyclonal and presents within 24 hours of birth. In WT mice, sIgM is produced prenatally and limits the expansion of IL-10⁺ B cells. Lack of the high affinity …

Electrospun Tamarindus Indica-Loaded Antimicrobial Pmma/Cellulose Acetate/Peo Nanofibrous Scaffolds For Accelerated Wound Healing: In-Vitro And In-Vivo Assessments, Elbadawy A. Kamoun, Elbadawy A. Kamoun

Nanotechnology Research Centre

In this work, Tamarindus indica (T. indica)-loaded crosslinked poly(methyl methacrylate) (PMMA)/cellulose acetate (CA)/poly(ethylene oxide) (PEO) electrospun nanofibers were designed and fabricated for wound healing applications. T. indica is a plant extract that possesses antidiabetic, antimicrobial, antioxidant, antimalarial and wound healing properties. T. indica leaves extract of different concentrations were blended with a tuned composition of a matrix comprised of PMMA (10 %), CA (2 %) and PEO (1.5 %), and were electrospun to form smooth, dense and continuous nanofibers as illustrated by SEM investigation. In vitro evaluation of T. indicaloaded nanofibers on normal human skin fibroblasts (HBF4) revealed a high …

Host-Defense Piscidin Peptides As Antibiotic Adjuvants Against Clostridioides Difficile, Adenrele Oludiran, Areej Malik, Andriana C. Zourou, Yonghan Wu, Steven P. Gross, Albert Siryapon, Asia Poudel, Kwincy Alleyne, Savion Adams, David S. Courson, Myriam L. Cotten, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The spore-forming intestinal pathogen Clostridioides difficile causes multidrug resistant infection with a high rate of recurrence after treatment. Piscidins 1 (p1) and 3 (p3), cationic host defense peptides with micromolar cytotoxicity against C. difficile, sensitize C. difficile to clinically relevant antibiotics tested at sublethal concentrations. Both peptides bind to Cu²⁺ using an amino terminal copper and nickel binding motif. Here, we investigate the two peptides in the apo and holo states as antibiotic adjuvants against an epidemic strain of C. difficile. We find that the presence of the peptides leads to lower doses of …

A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington

OES Faculty Publications

A new, simplified protocol for determining particulate adenosine triphosphate (ATP) levels allows for the assessment of microbial biomass distribution in aquatic systems at a high temporal and spatial resolution. A comparison of ATP data with related variables, such as particulate carbon, nitrogen, chlorophyll, and turbidity in pelagic samples, yielded significant and strong correlations in a gradient from the tributaries of the Chesapeake Bay (sigma-t = 8) to the open North Atlantic (sigma-t = 29). Correlations varied between ATP and biomass depending on the microscopic method employed. Despite the much greater effort involved, biomass determined by microscopy correlated poorly with other …

Gut Dysbiosis Correlates With Covid-19 Severity, Ednita Escobar

CMC Senior Theses

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) impacts not only respiratory but also gut and oral microbiomes, influencing the manifestations of COVID-19. Each person’s unique microbiome consists of microorganisms such as bacteria, fungi, and viruses, some of which are symbiotic and others potentially harmful. Alterations in the gut microbiome, specifically, can affect the severity and symptoms of COVID-19. A review of studies indicate a pattern of gut dysbiosis in COVID-19 patients characterized by a decrease in beneficial microbiota and/or an increase in opportunistic pathogens. This gut imbalance correlates with disease severity, suggesting that the gut microbiome plays a significant role …

Microbes Mediated Keratin Extraction From Poultry Waste And Assessment Of Its Efficacy In Growth Promotion Of Zea Mays And Triticum Aestivum, Imran Ahmad, Aisha Waheed Qurashi, Roheela Yasmeen

Journal of Bioresource Management

Feathers are a waste product of the poultry industry and are considered a major pollutant of the environment. Soil associated with poultry farms is a rich source of indigenous bacteria that are involved in biodegradation of keratin of the feathers of Gallus gallus domesticus. The present study was designed to understand the role of microbes in the degradation of a feather’s keratin and its possible utilization as a bio-protein for plants. In our studies, Keratinolytic activity was high at 37-45 ℃ and at 7.5-9.5 pH. Pseudomonas aeruginosa was identified by 16S rRNA sequencing as the most active keratinolytic strain. …

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …

Isolation And Characterization Of Microbes From Agricultural Fields And Their Evaluation For The Control Of Plant Pests, Hira Liaqat Ali, Sumaira Mazhar, Afeefa Chaudhry

Journal of Bioresource Management

Plant diseases due to pests cause huge loss to crop fields every year. For the control of plant pest, pesticides are under use. Fusarium wilt is caused by phytopathogen Fusarium oxysporum. More than 100 species were affected due to this disease caused by this virus. Fungi also affect onion plant crop yield every year, when chemical pesticides are applied to onion crop field. It will increase the cost of onion production and it is also dangerous for the environment and living organism other than the targeted pests. A number of microorganisms like fungi, bacteria and nematode are currently being …

Exploring Representation In Microbiology Introductory Courses Can Encourage A More Inclusive And Inspiring Environment For Students And Instructors, Jill A. Mikucki, Elizabeth Fozo

Feminist Pedagogy

Microbiology has a relatively brief history where significant discoveries are often linked with major events in human history - from disease outbreak to industrialization to climate change. The founders of key microbiological principles span across continents, genders, ethnicities, and socioeconomic status. However, the portrait described in many introductory textbooks center around a lone, typically white male scientist. Such narratives not only are misleading regarding the development of key principles in microbiology but can also reinforce inappropriate stereotypes as to whom belongs in microbiology. In our introductory microbiology course, we designed group work for Zoom break-out rooms to help engage students …

Protocol For An Agent-Based Model Of Recombination In Bacteria Playing A Public Goods Game, Isaiah Paolo A. Lee, Omar T. Eldakar, J. Peter Gogarten, Cheryl P. Andam

Biology Faculty Articles

Agent-based models are composed of individual agents coded for traits, such as cooperation and cheating, that interact in a virtual world based on defined rules. Here, we describe the use of an agent-based model of homologous recombination in bacteria playing a public goods game. We describe steps for software installation, setting model parameters, running and testing models, and visualization and statistical analysis. This protocol is useful in analyses of horizontal gene transfer, bacterial sociobiology, and game theory.

For complete details on the use and execution of this protocol, please refer to Lee et al.¹

Interactions Between Streptococcus Agalactiae And Candida Albicans Affect Persistence And Virulence, Kathryn Patenaude

Electronic Theses and Dissertations

Streptococcus agalactiae (Group B Streptococcus or GBS), a Gram-positive bacterium, and Candida albicans, a polymorphic fungus, are commensal microbes in most of the population they colonize but are also capable of causing severe and sometimes fatal infections in certain patient groups. Both organisms share similarities including the colonization the same tissue environments and causing infections in specific patient groups including those who are newborn, pregnant, suffering from chronic conditions like diabetes and HIV, as well as elderly patients. Previous research discovered that GBS and C. albicans can synergize to enhance the colonization of GBS in the bladders of mice, but …