Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Medicine and Health Sciences (1925)
- Virology (1373)
- Biology (1306)
- Environmental Microbiology and Microbial Ecology (1237)
- Bacteriology (1173)
-
- Genetics and Genomics (1053)
- Biochemistry, Biophysics, and Structural Biology (1012)
- Cell and Developmental Biology (857)
- Pathogenic Microbiology (768)
- Physical Sciences and Mathematics (751)
- Medical Specialties (719)
- Medical Sciences (710)
- Immunology and Infectious Disease (683)
- Molecular Biology (617)
- Cell Biology (444)
- Plant Sciences (425)
- Biochemistry (412)
- Diseases (408)
- Ecology and Evolutionary Biology (407)
- Medical Immunology (375)
- Molecular Genetics (364)
- Biotechnology (356)
- Infectious Disease (340)
- Animal Sciences (300)
- Biological Phenomena, Cell Phenomena, and Immunity (300)
- Environmental Sciences (299)
- Genetics (297)
- Medical Pathology (286)
- Institution
-
- University of Nebraska - Lincoln (876)
- Brigham Young University (474)
- Old Dominion University (308)
- Aga Khan University (277)
- Dartmouth College (237)
-
- University of South Florida (233)
- University of Kentucky (206)
- University of Arkansas, Fayetteville (199)
- University of Nevada, Las Vegas (199)
- Loyola University Chicago (198)
- South Dakota State University (186)
- Loma Linda University (167)
- Wright State University (165)
- Virginia Commonwealth University (136)
- Chulalongkorn University (135)
- Munster Technological University (129)
- University of Central Florida (114)
- University of Dayton (114)
- City University of New York (CUNY) (110)
- The University of Southern Mississippi (105)
- Clemson University (101)
- Eastern Illinois University (97)
- The Texas Medical Center Library (92)
- Portland State University (91)
- East Tennessee State University (88)
- University of Louisville (69)
- California Polytechnic State University, San Luis Obispo (67)
- Nova Southeastern University (64)
- Wayne State University (62)
- Technological University Dublin (60)
- Keyword
-
- Microbiology (321)
- Bacteria (220)
- Microbiome (152)
- Metabolism (109)
- Biofilm (107)
-
- Genetics (104)
- Microbiology and Immunology (102)
- Antibiotic resistance (86)
- Staphylococcus aureus (86)
- Cyanobacteria (80)
- Escherichia coli (78)
- Biofilms (76)
- Pseudomonas aeruginosa (76)
- Animals (72)
- Immunology (72)
- Biological sciences (64)
- HIV (64)
- Humans (62)
- Biology (61)
- Virus (60)
- Antibiotics (59)
- Gene expression (59)
- Virulence (58)
- Fungi (54)
- Mice (54)
- Bacterial (53)
- Bacteriophage (53)
- Microbial ecology (53)
- Physiology (53)
- Bacteriology (51)
- Publication Year
- Publication
-
- Nebraska Center for Virology: Faculty Publications (493)
- Journal of Undergraduate Research (318)
- Electronic Theses and Dissertations (304)
- Theses and Dissertations (269)
- Department of Pathology and Laboratory Medicine (235)
-
- Dartmouth Scholarship (203)
- Loma Linda University Electronic Theses, Dissertations & Projects (167)
- Biology Faculty Publications (158)
- Master's Theses (147)
- Dissertations (129)
- Browse all Theses and Dissertations (109)
- USF Tampa Graduate Theses and Dissertations (108)
- Graduate Theses and Dissertations (105)
- Masters Theses (94)
- Thai Environment (90)
- Dissertations and Theses (Open Access) (87)
- Papers in Microbiology (81)
- Theses (78)
- Biological Sciences Faculty Publications (76)
- Faculty Publications (73)
- Honors Theses (71)
- UNLV Theses, Dissertations, Professional Papers, and Capstones (71)
- Molecular Biosciences Faculty Publications (61)
- Publications and Research (61)
- Articles (57)
- OES Faculty Publications (52)
- All Theses (51)
- Legacy Theses & Dissertations (2009 - 2024) (49)
- Open Access Theses & Dissertations (49)
- Tanzania Journal of Science (48)
- Publication Type
- File Type
Articles 2401 - 2430 of 8152
Full-Text Articles in Microbiology
Investigating Streptococcus Pneumoniae And Adenovirus Co-Infections Of Lung Epithelial Cells, Mark Nicholas Calabro
Investigating Streptococcus Pneumoniae And Adenovirus Co-Infections Of Lung Epithelial Cells, Mark Nicholas Calabro
Browse all Theses and Dissertations
Co-infection is common among viruses and bacteria in the human respiratory system. Adenovirus (AdV) and Streptococcus pneumoniae are clinically relevant respiratory pathogens that cause morbidity and mortality in a variety of patient populations with the highest morbidity occurring among immunocompromised individuals, but also prevalent in infants and the elderly. Acute respiratory distress syndrome may become severe in healthy individuals when co-infection with S. pneumoniae and AdV occurs due to synergistic effects of the pathogens on the host. I hypothesized that S. pneumoniae infection decreases AdV transduction of airway epithelia. To test this hypothesis, we utilized the polarized immortalized airway epithelial …
Determining The Effects Of Imidacloprid On Non-Target Soil Organisms In Hemlock Stands, Braley Burke
Determining The Effects Of Imidacloprid On Non-Target Soil Organisms In Hemlock Stands, Braley Burke
Graduate Theses, Dissertations, and Problem Reports (ETD)
The hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae), is an invasive insect that is causing mortality of eastern hemlock trees, Tsuga canadensis, and Carolina hemlock trees, Tsuga caroliniana, across the eastern United States. To protect these ecologically important tree species, a neonicotinoid insecticide, imidacloprid, is commonly used. Imidacloprid is an effective treatment and can remain effective against HWA for four to six years but long-term (≥ one year after application) non-target effects of imidacloprid on forest ecosystems are not well-studied. This study examined terrestrial non-target effects of imidacloprid in hemlock stands with different treatment histories to …
Effects Of Biofertilizer On Soil Nutrient Cycling And The Productivity Of Bioproduct Crops In Marginal Soils, Kieran B. Liseski
Effects Of Biofertilizer On Soil Nutrient Cycling And The Productivity Of Bioproduct Crops In Marginal Soils, Kieran B. Liseski
Graduate Theses, Dissertations, and Problem Reports (ETD)
Recently there has been increased interest in the use of marginal lands in order to grow bioproduct crops. Utilizing marginal lands to grow bioproduct crops such as Miscanthus x giganteus and Panicum virgatum could not only improve soil quality and minimize negative environmental impacts on the surrounding ecosystems but could also offer economic benefits to growers in rural areas. Because marginal soils tend to reduce crop yields compared to prime farmlands even when growing bioproduct crops, which tend to be more robust than traditional food crops, augmenting the soil with biofertilizers (i.e., the direct addition of viable microbial cells) could …
Circadian Rhythmicity And Melatonin Sensitivity In The Human Gut Commensal Bacterium Klebsiella Aerogenes, Kinga Graniczkowska
Circadian Rhythmicity And Melatonin Sensitivity In The Human Gut Commensal Bacterium Klebsiella Aerogenes, Kinga Graniczkowska
Theses and Dissertations--Biology
While the expression of circadian rhythms is nearly universal among multicellular eukaryotic organisms, demonstration of this phenomenon in prokaryotes has been largely restricted to photosynthetic cyanobacteria until very recently. Further, growing interest in gastrointestinal microbiomes has revealed a complex temporal relationship between the gastrointestinal clock and the bacterial microbiome within. At least one member of the gut microbiome, Klebsiella (née Enterobacter) aerogenes, responds to the indoleamine hormone melatonin, secreted by the gastrointestinal system itself. Further research revealed that K. aerogenes also expresses a circadian rhythm in motility and gene expression that is temperature compensated. Although rhythmicity is unaltered …
Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud
Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud
Department of Food Science and Technology: Faculty Publications
Background: Oral microbiota is believed to play important roles in systemic diseases, including cancer. Methods: We collected oral samples (tongue, buccal, supragingival, and saliva) and pancreatic tissue or intestinal samples from 52 subjects, and characterized 16S rRNA genes using high-throughput DNA sequencing.
Results: Bray–Curtis plot showed clear separations between bacterial communities in the oral cavity and those in intestinal and pancreatic tissue samples. PERMANOVA tests indicated that bacterial communities from buccal samples were similar to supragingival and saliva samples, and pancreatic duct samples were similar to pancreatic tumor samples, but all other samples were significantly different from each …
Targeting Transferrin Binding Protein A For Vaccine Development In Neisseria Gonorrhoeae, Ashley Greenawalt
Targeting Transferrin Binding Protein A For Vaccine Development In Neisseria Gonorrhoeae, Ashley Greenawalt
Theses and Dissertations
Neisseria gonorrhoeae, the causative agent of the sexually-transmitted infection gonorrhea, has recently been labeled a superbug. With dwindling treatment options, there is urgent need for a gonococcal vaccine. TonB-dependent transporters (TDTs) are important gonococcal virulence factors that allow the gonococcus to pirate metals directly from host proteins. The TDTs, TbpA and TbpB, are promising vaccine targets because both proteins are expressed and highly conserved in gonococcal strains, and they are not subject to high-frequency antigenic variation. Because the Tbps bind to host protein as their natural function, our immune system does not recognize them as foreign antigens; thus, immunogenicity is …
Evolution And Clinical Relevance Of Vaginal Bifidobacterium Breve In The Vaginal Environment, Nicole R. Jimenez
Evolution And Clinical Relevance Of Vaginal Bifidobacterium Breve In The Vaginal Environment, Nicole R. Jimenez
Theses and Dissertations
The vaginal microbiome is important in reproductive health and disease and is often dominated by lactobacilli. However, there are many other community state types dominated by single species that are still not well characterized. Bifidobacterium species such as Bifidobacterium breve and Bifidobacterium longum have been observed to dominate vaginal profiles. Bifidobacteria are important in infant gut development, but little is known about their role in vaginal health. Thus, we sought to use a multisystem approach to better characterize Bifidobacterium species present in the vaginal microbiome with an emphasis on B. breve. Eight strains of B. breve were isolated from vaginal …
Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla
Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla
Dissertations and Theses
Parasitoid wasps are effective biological control agents that have evolved intricate host immune suppression strategies to overcome host immune defenses. The most important anti-parasite defense mechanism is encapsulation, where the host’s blood cells surround the wasp egg. In the Drosophila/Leptopilina host-parasitoid system, extracellular vesicles (EVs) are oviposited along with the wasp egg. The EVs possess spikes and contain hundreds of proteins, some of which enable wasp eggs to escape encapsulation by changing the morphology and function of hemocytes, or killing them. Previous studies have identified an abundant surface/spike protein (SSp40) from Leptopilina heterotoma EVs. While p40, a predicted …
Il-36g Cytokine Induction In Oral Epithelial Cells Triggered By Treponema Denticola And Their Role In Chronic Periodontitis, Christopher Blake
Il-36g Cytokine Induction In Oral Epithelial Cells Triggered By Treponema Denticola And Their Role In Chronic Periodontitis, Christopher Blake
Theses and Dissertations
Periodontal disease is a polymicrobial disease affecting 10-15% of the population. Periodontal disease affects the quality of life by reducing mastication and potentially causing tooth loss. Periodontal disease is also linked to more severe, systemic diseases such as cardiovascular disease and rheumatoid arthritis. Development of the diseased state occurs when the plaque biofilm shifts from healthy to dysbiotic. The shift to a dysbiotic biome brings with it a shift in bacterial presence, specifically an increase in gram-negative bacteria, such as T. denticola. T. denticola is a gram-negative, anaerobic spirochete whose relationship with oral epithelial cells is poorly understood. Preliminary data …
Stomatal Conductance And Reed Canary Grass Suppression Of Native Michigan Trees, David E. Martinez Vasquez, Martin L. Vanderschoot, David Warners
Stomatal Conductance And Reed Canary Grass Suppression Of Native Michigan Trees, David E. Martinez Vasquez, Martin L. Vanderschoot, David Warners
Faculty and Professional Research
Reed canary grass (Phalaris arundinacea), a prominent invasive understory species, threatens native Michigan biodiversity statewide. A notable affected area includes a stretch of agricultural land along Schooley Drain in Caledonia, MI, located in the headwaters of the Plaster Creek watershed. Our study pursues the following questions: “Do native trees provide enough shade to reduce the growth of Reed canary grass?” and “Which native trees best transpire water from a floodplain?”: To answer these questions, we initiated a long-term evaluation of seven different species of native Michigan trees to investigate which species best inhibits the growth of reed canary grass and …
Plaster Creek Floodplain And Adjacent Ravines Near Stanaback Park: Botanical Inventory Highlights And Management Considerations, David Warners, Garrett Crow, Haley Weesies
Plaster Creek Floodplain And Adjacent Ravines Near Stanaback Park: Botanical Inventory Highlights And Management Considerations, David Warners, Garrett Crow, Haley Weesies
Faculty and Professional Research
In the summer of 2021, the research team visited this area of ravines and floodplain a total of twenty-one times to conduct our field research. During the visits, they carefully walked throughout different sections of the study site, identifying each vascular plant species they saw growing there and observing how the flora developed throughout the season. In addition to keeping detailed field notes, they documented permanent records of the findings of our inventory by collecting voucher specimens that have been deposited in the Calvin University Herbarium. Additionally, they sent duplicate specimens to the Michigan State University Herbarium and/or University of …
Botanical Inventory Highlights And Management Considerations For Covenant Park, David Warners, Garrett Crow, Haley Weesies
Botanical Inventory Highlights And Management Considerations For Covenant Park, David Warners, Garrett Crow, Haley Weesies
Faculty and Professional Research
In the spring and summer of 2021, Calvin University students and faculty conducted a botanical inventory and assessment of the natural areas in Covenant Park, located at 3724 Shaffer Avenue SE, Kentwood, MI 49512. Given that the property was recently acquired by the City of Kentwood Parks & Recreation, the purpose of this inventory is to inform Kentwood Parks and Recreation staff about the site’s floristic quality, diversity, and ecological significance. The specific objectives of this study are to 1) provide a comprehensive inventory of the species of plants occurring on the property, 2) identify particular areas that would benefit …
การผลิต ลักษณะสมบัติและการยับยั้งราที่ก่อโรคในพืชของสารลดแรงตึงผิวชีวภาพจาก Bacillus Licheniformis F2.2, สิริตา เสียมไหม
การผลิต ลักษณะสมบัติและการยับยั้งราที่ก่อโรคในพืชของสารลดแรงตึงผิวชีวภาพจาก Bacillus Licheniformis F2.2, สิริตา เสียมไหม
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ศึกษาความสามารถในการยับยั้งราก่อโรคในพืช การผลิตสารลดแรงตึงผิวชีวภาพ และผลของปัจจัยทางกายภาพที่มีต่อประสิทธิภาพในการยับยั้งราก่อโรคในพืชของสารลดแรงตึงผิวชีวภาพจาก Bacillus licheniformis F2.2 รวมถึงหาภาวะที่เหมาะสมสำหรับการผลิตสารลดแรงตึงผิวชีวภาพ จากนั้นทำบริสุทธิ์ และศึกษาลักษณะสมบัติเบื้องต้นของสารลดแรงตึงผิวชีวภาพ แล้วทดสอบการประยุกต์ใช้เพื่อยับยั้งการเกิดโรคใบไหม้ในต้นข้าว ผลการวิจัยพบว่า B. licheniformis F2.2 สามารถยับยั้งราก่อโรคในพืชได้ทั้ง 7 ชนิด ซึ่งได้แก่ Acremonium furcatum, Colletotrichum gloeosporioides, Fusarium moniliforme, Fusarium proliferatum, Fusarium solani, Pyricularia oryzae และ Phytophthora palmivora โดยมีเปอร์เซ็นต์การยับยั้งอยู่ระหว่าง 34.79±6.29-44.51±1.29% เมื่อทดสอบสมบัติในการผลิตสารลดแรงตึงผิวชีวภาพ โดยทดสอบแอกทิวิตีการสลายเม็ดเลือดแดง, การยุบตัวของน้ำเลี้ยงเซลล์, การกระจายตัวของน้ำมัน และการเกิดอิมัลชัน พบว่าส่วนใสของน้ำเลี้ยงเชื้อของ B. licheniformis F2.2 ให้ผลบวกกับทุกการทดสอบ ซึ่งแสดงว่า B. licheniformis F2.2 สามารถผลิตสารลดแรงตึงผิวชีวภาพได้ จากการศึกษาผลของอุณหภูมิและความเป็นกรดเบสต่อประสิทธิภาพในการยับยั้งราก่อโรคในพืชของส่วนใสของน้ำเลี้ยงเชื้อของ B. licheniformis F2.2 พบว่าเมื่อผ่านการบ่มน้ำเลี้ยงเชื้อที่ 20-121 องศาเซลเซียส และที่ pH 2-12 พบว่าสมบัติการเกิดอิมัลชันของสารลดแรงตึงผิวชีวภาพก็ยังมีความเสถียร และประสิทธิภาพการยับยั้งราก่อโรคในพืชทั้ง 7 ชนิดยังคงอยู่ โดยสามารถยับยั้ง P. oryzae ซึ่งเป็นสาเหตุของโรคไหม้ในข้าวได้มากที่สุด จากการแปรผันแหล่งคาร์บอนและแหล่งไนโตรเจนพบว่าอาหาร MOLP ที่มีซูโครสเป็นแหล่งคาร์บอน, แอมโมเนียมคลอไรด์และสารสกัดจากยีสต์เป็นแหล่งไนโตรเจนส่งเสริมการเจริญเติบโตของ B. licheniformis F2.2 ได้ดีที่สุด และเหมาะสมต่อการผลิตสารลดแรงตึงผิวชีวภาพที่มีฤทธิ์ยับยั้งราก่อโรคในพืช โดยมีค่าดัชนีการเกิดอิมัลชันที่ 24 ชั่วโมง (E24) 62.92±2.30% สำหรับความสัมพันธ์ระหว่างระยะเวลาการเจริญกับการผลิตสารลดแรงตึงผิวชีวภาพที่มีฤทธิ์ยับยั้งราก่อโรคในพืช พบว่าเมื่อเลี้ยง B. licheniformis F2.2 ในอาหาร MOLP พบว่ามีความสามารถในการยับยั้งราก่อโรคในพืชทั้ง 7 ชนิดสูงสุดเมื่อแบคทีเรียเข้าสู่ stationary phase ที่ 24 ชั่วโมง เมื่อสกัดสารลดแรงตึงผิวชีวภาพด้วยเมธานอล 100% (ปริมาตร/ปริมาตร) …
Detection And Potential Virulence Of Viable But Non-Culturable (Vbnc) Listeria Monocytogenes: A Review, Nathan E. Wideman, James D. Oliver, Philip Glen Crandall, Nathan A. Jarvis
Detection And Potential Virulence Of Viable But Non-Culturable (Vbnc) Listeria Monocytogenes: A Review, Nathan E. Wideman, James D. Oliver, Philip Glen Crandall, Nathan A. Jarvis
Food Science Faculty Publications and Presentations
The detection, enumeration, and virulence potential of viable but non-culturable (VBNC) pathogens continues to be a topic of discussion. While there is a lack of definitive evidence that VBNC Listeria monocytogenes (Lm) pose a public health risk, recent studies suggest that Lm in its VBNC state remains virulent. VBNC bacteria cannot be enumerated by traditional plating methods, so the results from routine Lm testing may not demonstrate a sample’s true hazard to public health. We suggest that supplementing routine Lm testing methods with methods designed to enumerate VBNC cells may more accurately represent the true level of risk. This review …
The Gut Microbiome Of Hapalemur Griseus Griseus, Propithecus Diadema, And Propithecus Coquereli: A Comparative Study Between Wild And Captive Lemur Species, Brenna Ritchie
Graduate Research Theses & Dissertations
Madagascar is home to thousands of endemic species, making it a biodiversity hotspot that is rapidly losing its fauna due to deforestation and human expansion. Efforts to restore and preserve this unique island are ongoing and several researchers have placed their focus on preventing species extinctions. One research avenue that can help contribute to these efforts is to study health and wellness of animals located in areas affected by these changes. In this study, I sought to characterize microbial community composition of two native lemur species found in Madagascar and compare those profiles to similar species found in captivity in …
Predicting, Monitoring And Controlling The Growth Of Listeria In Complex Food Matrices, Laura Mary Nyhan
Predicting, Monitoring And Controlling The Growth Of Listeria In Complex Food Matrices, Laura Mary Nyhan
Theses
Listeria monocytogenes is a foodborne pathogen which is a significant challenge in food production, particularly for ready-to-eat (RTE) products. Incidence of Listeria in RTE foods can be reduced by the application of intelligent combinations of preservative factors or hurdles, while data quantifying the efficacy of hurdle combinations can be exploited and used in the area of predictive microbiology. Traditional culture-based techniques, such as viable plate counts, are commonly used to monitor the growth/survival of microorganisms in foods, however these methods are tedious, time-consuming and due to their destructive nature, are associated with low reproducibility and high variability. Therefore, rapid, non-invasive …
Comparison Of The Effects Of Land Use / Land Cover On Water Quality And The Intertidal Marine Macroalgae Communities At The Fluvial Outflows Of The Dingle Peninsula, Cassandra Lew
Theses
The Milltown, Feohanagh, and Owenmore river basins located on the Dingle Peninsula in Ireland were studied to see how variation in land use and land cover (LU/LC) affected water quality and the macroalgal communities at each river’s respective fluvial outflow. Abundance and composition of macroalgae in river and coastal water bodies have been designated as an indicator of water quality according to the Water Framework Directive 2000. The results of this study found that the Feohanagh’s macroalgal community had the highest species richness for most months while the Milltown had the highest Shannon Diversity Index. The Owenmore’s community was consistently …
Investigating The Roles Of Lipids In Staphylococcus Aureus Infection, Xi Chen
Investigating The Roles Of Lipids In Staphylococcus Aureus Infection, Xi Chen
Dissertations
The Gram-positive bacterium Staphylococcus aureus is a major threat to public health and causes a multitude of infections, ranging from mild skin and soft infection, to more severe diseases including sepsis, osteomyelitis and infective endocarditis. As a successful pathogen, S. aureus employs various mechanisms to invade host tissues, evade immune responses, and survive in the host environment. One critical adaptive trait of S. aureus that promotes virulence and survival is the ability to maintain membrane homeostasis via flexible modifications to its lipid composition in response to the surrounding lipid environment. Phospholipids are the major component of the bacterial membrane and …
F Plasmids In Escherichia Coli Decrease Permissivity To Coliphage, Cesar Eber Montelongo Hernandez
F Plasmids In Escherichia Coli Decrease Permissivity To Coliphage, Cesar Eber Montelongo Hernandez
Dissertations
The urinary tract contains a community of bacteria called the urinary microbiota (urobiota) thatmay be relevant to health; the genomic component of the urobiota is the urinary microbiome (urobiome). Urinary bacteria have been associated with both asymptomatic states and disease conditions, such as urinary tract infection (UTI), overactive bladder (OAB), and urge urinary incontinence (UUI). Some bacteria, such as E. coli, are considered urinary pathogens (uropathogens) but also can be commensals. Bacteriophage (phage) are ubiquitous in nature and likely shape bacterial populations in every niche; thus, phage may be one factor that modulates the urobiota. Phages have a specific host …
Identification And Characterization Of Calcium As A Biofilm Promoting Signal By Vibrio Fischeri, Alice Hannah Tischler
Identification And Characterization Of Calcium As A Biofilm Promoting Signal By Vibrio Fischeri, Alice Hannah Tischler
Dissertations
The marine bacterium, V. fischeri actively engages in an exclusive partnership in the light organ of its squid host, Euprymna scolopes. A critical step in this colonization process is the formation of a bacterial aggregate, or biofilm, which is a community of bacteria embedded within a protective extracellular matrix. While V. fischeri readily forms biofilms in nature, genetic overexpression must be utilized to achieve biofilm formation in the laboratory. Recent work investigating media composition led myself and others to evaluate how seawater salts impacted growth and biofilm formation in a number of mutant backgrounds, leading to the identification of calcium …
Assessing The Role Of The Interaction Between Polyamines And Heparan Sulfate In Coxsackievirus B3 Viral Infection, Oreoluwa Omoba
Assessing The Role Of The Interaction Between Polyamines And Heparan Sulfate In Coxsackievirus B3 Viral Infection, Oreoluwa Omoba
Master's Theses
Non-polioenteroviruses are highly infectious viruses that typically cause mild asymptomatic cases but can cause severe disease such as aseptic meningitis and dilated cardiomyopathy. Coxsackievirus B3 (CVB3) is a member of this group and is prevalent in the United States and Eastern Asia. Viruses like CVB3 rely on the host cell for many molecules in order to replicate. One such set of molecules is the polyamines. Polyamines are small, positively charged molecules that play a role in a multitude of cellular processes including RNA/DNA stabilization, gene expression, translation, and regulating membrane fluidity. Previous studies have shown CVB3 relies on polyamines for …
Elucidating Regulatory Connections Between The Second Messenger Cyclic-Di-Gmp With Biofilm And Motility Phenotypes Of Vibrio Fischeri, Ali Razvi
Master's Theses
The symbiosis between the gram-negative marine bacterium Vibrio fischeri and its host Euprymna Scolopes occurs when the bacteria reaches and colonizes the light organ. This pathway to colonization begins in the outer marine environment and finishes within the deep crypts of the light organ, with states of biofilm formation and dispersal in between. This switch between biofilm formation to dispersal is important as the bacteria transitions from the surface on the light organ into a pore leading to the interior of the light organ. This dispersal is regulated by LAP system which is dependent on the second messenger c-di-GMP. Through …
Free-Living Diazotrophs And The Nitrogen Cycle In Natural Grassland Revealed By Culture Dependent And Independent Approaches, Amrit Koirala
Free-Living Diazotrophs And The Nitrogen Cycle In Natural Grassland Revealed By Culture Dependent And Independent Approaches, Amrit Koirala
Electronic Theses and Dissertations
Biological nitrogen fixation contributes to half of the global supply of nitrogen to the biosphere. It is carried out by a diverse group of prokaryotes called diazotrophs via the nitrogenase enzyme. Nitrogen fixation research is focused on the narrow group of symbiotic diazotrophs, and the vast majority of free-living diazotrophs which contribute significantly to fixed nitrogen are yet to be explored. The goal of this research was to access phylogeny of diazotrophs considering the most up-to-date genomic information and apply that knowledge to understand the diversity of free-living diazotrophs in a natural grassland ecosystem, both by culture dependent and independent …
A Survey Of Opportunistic Fungi In The Portsmouth, Nh Region, Chloe E. Richard
A Survey Of Opportunistic Fungi In The Portsmouth, Nh Region, Chloe E. Richard
Honors Theses and Capstones
Opportunistic mycoses are caused by ubiquitous fungi that we encounter daily. This study identified the most common opportunistic fungi in a local area during the current winter season. A survey of fungi was conducted in the Portsmouth, New Hampshire region by taking environmental samples from both indoor and outdoor locations. The samples were then cultured and identified using colony morphology, microscopic characteristics, and biochemical testing. Despite the cold weather, the results showed that fungal species are still prevalent outdoors, with the most variation in single samples coming from areas with exposed soil and decaying vegetation, while less fungal presence was …
Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio
Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio
Honors Theses and Capstones
Plant roots are home to a wide variety of beneficial microbes; understanding and optimizing plant-microbe interactions may be critical to enhance global food security in a sustainable, equitable way. With the help of their nitrogen-fixing bacterial partner, Frankia, actinorhizal plants form symbiotic root nodules and play important roles in agroforestry and land reclamation. However, Frankia does not live alone in nodules, and the other microbial residents may contribute to nodule formation and function. We collected root nodules from alder trees (Alnus sp.) in 2018 and 2019, then isolated DNA and individual bacterial strains to characterize the nodule microbial …
Global Coordination Between Gene Expression Processes In C. Crescentus, James Raymond Aretakis
Global Coordination Between Gene Expression Processes In C. Crescentus, James Raymond Aretakis
Wayne State University Dissertations
Gene expression is an essential process of all organisms which occurs in two steps, mRNA transcription, and translation and which is shut off by mRNA decay. For a bacterium to grow and divide, these steps need to be tuned to optimize the synthesis rates of thousands of proteins from their genes. Genome-wide experiments were used to determine the absolute transcription rates, mRNA degradation rates, and translation rates on a gene by gene basis in the model bacterium Caulobacter crescentus. This not only provides a system biology view of the organism’s gene expression resource allocation, but also provides a chance to …
A Review Of The Molecular Mediators Of Host-Baculovirus Interactions In Lepidoptera, Olivia Crouse
A Review Of The Molecular Mediators Of Host-Baculovirus Interactions In Lepidoptera, Olivia Crouse
Honors Program Theses
Iowa farmlands occupy approximately 85% of its 35.7 million acres, and Iowa leads the United States in corn and soybean production, with an estimated 2.58 billion and 502 million bushels of corn and soybean produced in 2019, respectively. This successful trend in annual yields has span forty plus years and been consequential to the simultaneous implementation of agricultural- and science-based practices. Genetically modified corn and soybean crop varieties express genes from Bacillus thuringiensis (Bt) which encode insecticidal proteins that protect, with high specificity, against insect pests. While researchers continue to study the molecular mechanism(s) of Bt extensively, alternative environmentally safe …
Bacillus Bacteriophage Q11 May Have A 5' Covalently Attached Protein, Emily Cornelius
Bacillus Bacteriophage Q11 May Have A 5' Covalently Attached Protein, Emily Cornelius
Honors Program Theses
Bacteriophages (phages) are viruses that specifically parasitize on bacteria and are found almost everywhere. Phages Phi 29 and Q11 are both small phages found in soil that attack Bacillus hosts. Previous Phi 29 studies verified a covalently bonded protein at the 5’ end of its double-stranded linear DNA. Q11 may have a similar 5’ terminal protein, which blocks complete sequencing of that DNA region. Because Q11 and phi29 are both small short-tailed phages that infect similar hosts, it could be possible the proteins are structurally similar. In previous work, I have attempted to use restriction endonuclease and exonuclease enzyme digests …
Evaluation Of Archeal Growth On Complex Media And Antibiotic Regimes, Melanie Miller
Evaluation Of Archeal Growth On Complex Media And Antibiotic Regimes, Melanie Miller
Honors Program Theses
The first Archaea that were studied by scientists came from extreme environments such as fissures at the bottom of oceans where hydrothermal vents formed. It was perhaps surprising that later sampling of environmental DNA revealed Archaea inhabit normal environments as well, for example they are globally distributed in soils. These mesophilic soil species were only recently grown in laboratory pure cultures. In this study, we will expand on this work by feeding the community of soil microbes with various dilutions of tryptic soy broth and other complex media in combination with an antibiotic regime. This will allow us to compare …
The Search For Life In Extreme Environments: Measuring Diversity And Quantity Of Archaea In Wind Cave National Park, Nicole Geerdes
The Search For Life In Extreme Environments: Measuring Diversity And Quantity Of Archaea In Wind Cave National Park, Nicole Geerdes
Honors Program Theses
Archaea have the potential to play an essential role in their environment at the base of the food chain. In particular, most of the known species in the phylum Thaumarchaea are autotrophs that can fix their own carbon using energy from ammonia oxidation, that is, they produce their own organic molecules from carbon dioxide by burning nitrogen-based fertilizer. Since their discovery, it has been difficult to learn more about these microbes because they do not grow well in pure laboratory culture. Therefore, much of what is known about them comes from analyzing environmental DNA samples. This allowed researchers to discover …