Microbiology Commons^™

Functional Characterization Of Aggregatibacter Actinomycetemcomitans Qsebc : A Bacterial Adrengeric Receptor And Global Regulator Of Virulence., Whitney Weigel

Electronic Theses and Dissertations

In order for a pathogen to successfully colonize the host, it must be able to acquire essential nutrients and regulate gene expression to respond to environmental fluctuations. One mechanism bacteria have evolved in order to detect these fluctuations and respond is the two component signal transduction systems (TCS). Aggregatibacter actinomycetemcomitans, a dental commensal associated with localized aggressive periodontitis, contains a TCS designated QseBC that was previously shown to regulate expression of several iron acquisition genes, biofilm formation and virulence, but the activating signal was unknown []. QseBC is a conserved TCS in the Enterobacteriaceae and Pasteurellaceae, but the activating signal …

Examination Of The Chagas Disease Vector, Triatoma Gerstackeri, In The Lower Rio Grande Valley, Alfredo Flores

Theses and Dissertations

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, which is carried by an insect vector of the family Reduviidae, and of the subfamily Triatomina. The species Triatoma gerstaeckeri is identified as the primary vector of T. cruzi within the Rio Grande Valley. Species of Triatoma gerstaeckeri were trapped in La Sal del Rey National Refuge in 2012 and 2013.

Data indicates a seasonal dispersal pattern of activity for T. gerstaeckeri. Optimal time of capture was between 1-2 hours after sunset. Different methods were utilized to determine the best combination of lures. Results indicate that the UV-light alone is …

Influence Of Lactobacillus Rhamnosus Isolated From “Amabere Amaruranu” Cultured Milk On Adipogenesis, Justin E. Kotala

Electronic Theses and Dissertations

This study was performed to test the in vitro effects of a Lactobacillus rhamnosus isolate from “amabere amaruranu”, a traditional Kenyan cultured milk, on 3T3-L1 and Caco-2 cell lines. Cultures of fully mature 3T3-L1 adipocytes were treated with bacterial isolate cell extract (CE), filtered spent broth (FSB) from overnight bacterial culture, or with a PBS control. Expression levels of PPAR³1 and 2, C/EBP±, and ATGL proteins in 3T3-L1 cells were upregulated by FSB treatment. CE treatment did not affect protein expression levels. Expression of MTTP and SREBP-1c proteins in Caco-2 cells showed no change with either treatment. Optical density measurements …

The Human Gut Mycobiome: Pitfalls And Potentials — A Mycologist's Perspective, Mallory J. Suhr, Heather E. Hallen-Adams

Department of Food Science and Technology: Faculty Publications

We have entered the Age of the Microbiome, with new studies appearing constantly and whole journals devoted to the human microbiome. While bacteria outnumber other gut microbes by orders of magnitude, eukaryotes are consistently found in the human gut, and are represented primarily by the fungi. Compiling 36 studies spanning from 1917 to 2015, we found at least 267 distinct fungal taxa have been reported from the human gut, and seemingly every new study includes one or more fungi not previously described from this niche. This diversity, while impressive, is illusory. If we examine gut fungi, we will quickly observe …

A Lipidomics Approach To The Viral–Host Dynamics Of The Unicellular, Eukaryotic Alga Chlorella Variabilis And Its Viral Pathogen, Pbcv-1, Suzanne L. Rose

School of Biological Sciences: Dissertations, Theses, and Student Research

This thesis focuses on the sterol and sphingolipid composition in the unicellular, green alga Chlorella variabilis and the lipidomic changes that occur during viral infection. Using lipid analysis by mass spectrometry, we have identified the major sterol, ergosterol and sphingolipid, glucosyl inositol phosphoceramide (GIPC) as constituents of C. variabilis cell membranes. Sterols and sphingolipids have essential biological functions such as hormone-based signaling, plant defense, and apoptosis as well as critical roles in structural components of the cell and organelle membranes. In chapters two and three, we focus on the characterization of sterol composition among both freshwater and marine alga …

Expansion Of The Chlorovirus Genus By Studies On Virus Natural History And Chlorella Host Metabolism, Cristian F. Quispe

School of Biological Sciences: Dissertations, Theses, and Student Research

Inland waters cover about 2.5 percent of our planet and harbor huge numbers of known and unknown microorganisms including viruses. Viruses likely play dynamic, albeit largely undocumented roles in regulating microbial communities and in recycling nutrients in the ecosystem. Phycodnaviruses are a genetically diverse, yet morphologically similar, group of large dsDNA-containing viruses (160- to 560-kb) that inhabit aquatic environments. Members of the genus Chlorovirus are common in freshwater. They replicate in eukaryotic, single-celled, chlorella-like green algae that normally exist as endosymbionts of protists in nature. Very little is known about the natural history of the chloroviruses and how they achieve …

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Molecular Targets Of Manuka Honey In Human Breast Cancer, Sarah Saif Al Qubaisi

Theses

The medicinal properties of Manuka honey have been extensively studied, particularly in terms of its wound healing and antimicrobial activities. We have previously demonstrated that Manuka honey also has anti-cancer properties against a variety of cancer cell types in vitro as well as in preclinical cancer models. The cellular targets of the anti-cancer activity of Manuka honey, however, remain unknown. For the present study, we selected the triple negative human breast cancer cell line, MDA-MB-231, to investigate susceptibility to Manuka honey and to identify the potential signaling pathways affected. MDA-MB-231 cancer cells are known to constitutively express activated STAT3 transcription …

Reduction Of Campylobacter Jejuni On Chicken Wingettes By Treatment With Caprylic Acid, Chitosan Or Protective Cultures Of Lactobacillus Spp., Ann Nicole Woo-Ming

Graduate Theses and Dissertations

Poultry is one of the main sources of protein in the United States and in 2014 Americans ate approximately 100 lbs per person. However, consumption of poultry products is strongly associated with foodborne illness from Campylobacter. In the first study, chitosan, caprylic acid and their combination were evaluated as a coating treatment for the reduction of Campylobacter jejuni on poultry products. For the initial screening trials, chitosan of three different molecular weights (15-50 kDa, 190-310 kDa and 400-600 kDa) was evaluated at three concentrations (0.5%, 1.0%, 2.0%) and separately, caprylic acid was tested at 0.5%, 1.0% and 2.0% using chicken …

Characterization Of Two Novel Gene Regulatory Systems In The Zoonotic Bacterium Bartonella Henselae, Nhan Tu

USF Tampa Graduate Theses and Dissertations

The genus Bartonella contains Gram-negative arthropod-borne bacteria that are found in many small animal reservoirs and are capable of causing human disease. Bacteria utilize a general stress response system to combat stresses from their surrounding environments. In α-proteobacteria, the general stress response system uses an alternate σ factor as the main regulator and incorporates it with a two-component system into a unique system. Our study identifies the general stress response system in the α-proteobacterium, Bartonella henselae, where the gene synteny is conserved and both the PhyR and alternate σ factor have similar sequence and domain structures with other α-proteobacteria. …

Pathogen Removal In Natural Wastewater Treatment And Resource Recovery Systems: Solutions For Small Cities In An Urbanizing World, Matthew Eric Verbyla

USF Tampa Graduate Theses and Dissertations

Sanitation, renewable energy, and food security are among the most pressing global development needs of the century, especially for small cities with rapid population growth. Currently, 53% of the world’s population either lacks access to improved sanitation or discharges fecal waste to the environment without treatment. Furthermore, 80% of food consumed in developing regions is produced by 500 million small farms, and while many of them are still rain-fed, irrigated agriculture is increasing. The post-2015 Sustainable Development Goals, recently adopted by the United Nations, include targets to address the water-energy-food nexus. Wastewater reuse in agriculture can be an important solution …

Intrinsic Challenges In Ancient Microbiome Reconstruction Using 16s Rrna Gene Amplification, Kirsten Ziesemer, Allison Mann, Krithivasan Sankaranarayanan, Hannes Schroeder, Andrew T. Ozga, Bernd W. Brandt, Egija Zaura, Andrea Waters-Rist, Menno Hoogland, Domingo C. Salazar-Garcia, Mark Aldenderfer, Camilla Speller, Jessica Hendy, Darlene A. Weston, Sandy J. Macdonald, Gavin H. Thomas, Matthew J. Collins, Cecil M. Lewis Jr., Corinne Hofman, Christina Warinner

Biology Faculty Articles

To date, characterization of ancient oral (dental calculus) and gut (coprolite) microbiota has been primarily accomplished through a metataxonomic approach involving targeted amplification of one or more variable regions in the 16S rRNA gene. Specifically, the V3 region (E. coli341–534) of this gene has been suggested as an excellent candidate for ancient DNA amplification and microbial community reconstruction. However, in practice this metataxonomic approach often produces highly skewed taxonomic frequency data. In this study, we use non-targeted (shotgun metagenomics) sequencing methods to better understand skewed microbial profiles observed in four ancient dental calculus specimens previously analyzed by amplicon …

Complete Genome Sequences Of Four Escherichia Coli St95 Isolates From Bloodstream Infections, Craig M. Stephens, Jeffrey M. Skerker, Manraj S. Sekhon, Adam P. Arkin, Lee W. Riley

Biology

Finished genome sequences are presented for four Escherichia coli strains isolated from bloodstream infections at San Francisco General Hospital. These strains provide reference sequences for four major fimH-identified sublineages within the multilocus sequence type (MLST) ST95 group, and provide insights into pathogenicity and differential antimicrobial susceptibility within this group.

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …

The Detection And Molecular Evolution Of Francisella Tularensis Subspecies, Mark K. Gunnell

Theses and Dissertations

Francisella tularensis is the etiological agent of tularemia, a zoonotic disease with worldwide prevalence. F. tularensis is a highly pathogenic organism and has been designated as a potential biothreat agent. Currently there are four recognized subspecies of F. tularensis: tularensis (type A), holarctica (type B), mediasiatica, and novicida. In addition, genomic studies have further subdivided type A tularensis into two subclassifications, type A.I and type A.II. These two subclassifications differ in geographic distribution with type A.I appearing mainly in the Eastern United States and type A.II appearing mainly in the Western United States. Because of differences of virulence among the …

Detection Methods And Intestinal Adherence Of Non-O157 Shiga Toxin-Producing Escherichia Coli, Zachary R. Stromberg

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Shiga toxin-producing Escherichia coli (STEC) are enteric pathogens of humans. Cattle serve as a reservoir and harbor STEC in their intestines. Intimin-positive STEC are referred to as enterohemorrhagic E.coli (EHEC). Seven serogroups (O26, O45, O103, O111, O121, O145, and O157) account for the majority of illness due to STEC and are hereafter referred to as STEC/EHEC-7. To improve detection, enrichment broths were compared for supporting growth of STEC-7 and STEC O104:H4 (STEC-8). In pure culture, STEC enriched in trypticase soy broth (TSB) had significantly greater growth compared to TSB containing antimicrobials. In fecal samples, E. coli broth enrichment yielded …

Spectrum Of Histopathological Findings In Postmenopausal Bleeding, Muhammad Usman Tariq, Romana Idress, Ahmed Raheem, Naila Kayani

Department of Pathology and Laboratory Medicine

Objective:To determine the frequencies of histopathological findings in endometrial and endocervical biopsy samples with clinical history of Postmenopausal Bleeding (PMB). Study Design:Descriptive cross-sectional study. Place and Duration of Study:Section of Histopathology, Department of Pathology and Laboratory Medicine, The Aga Khan University Hospital, Karachi, from February 2012 to January 2013. Methodology:Atotal of 157 consecutive endometrial and endocervical biopsy specimens with history of postmenopausal bleeding were included. After microscopic examination, frequencies of histological findings in different age groups were generated. Chi-square and independent sample t-tests were applied to see whether the difference was significant which was set at p < 0.05. Results:One hundred and twenty-one (77.1%) specimens showed benign pathologies while 36 (22.9%) were malignant. Endometrial polyp was seen in 67 (42.7%) cases followed by endometrial carcinomas in 25 (15.9%), endometrial hyperplasia in 21 (13.4%), cervical carcinoma in 12 (7.6%) and cervical polyps in 9 (5.7%) cases. Ahighly significant increase in the percentage of malignant and pre-malignant lesions was seen with increasing age group (p < 0.001). Mean age of patients with type-2 endometrial carcinoma was higher than type-1 endometrial carcinoma but statistical significance was not observed (70.2 ±6.5 vs. 61.8 ±9.1 years respectively, p=0.069). Conclusion:Although benign pathologies were more common in postmenopausal bleeding but the collective proportion of endometrial and cervical malignancies and pre-malignant conditions was quite high. Therefore, PMB should be urgently evaluated for cause and early commencement of treatment

Degradation Of The Cancer Genomic Dna Deaminase Apobec3b By Siv Vif, Allison M. Land, Jiayi Wang, Emily K. Law, Ryan Aberle, Andrea Kirmaier, Annabel Krupp, Welkin E. Johnson, Reuben S. Harris

Biological Sciences Department Publications

APOBEC3B is a newly identified source of mutation in many cancers, including breast, head/neck, lung, bladder, cervical, and ovarian. APOBEC3B is a member of the APOBEC3 family of enzymes that deaminate DNA cytosine to produce the promutagenic lesion, uracil. Several APOBEC3 family members function to restrict virus replication. For instance, APOBEC3D, APOBEC3F, APOBEC3G, and APOBEC3H combine to restrict HIV-1 in human lymphocytes. HIV-1 counteracts these APOBEC3s with the viral protein Vif, which targets the relevant APOBEC3s for proteasomal degradation. While APOBEC3B does not restrict HIV-1 and is not targeted by HIV-1 Vif in CD4-positive T cells, we asked whether related …

Cyclic Di-Gmp-Mediated Repression Of Swarming Motility By Pseudomonas Aeruginosa Pa14 Requires The Motab Stator, S. L. Kuchma, N. J. Delalez, L. M. Filkins, E. A. Snavely, J. P. Armitage, G. A. O'Toole

Dartmouth Scholarship

The second messenger cyclic diguanylate (c-di-GMP) plays a critical role in the regulation of motility. In Pseudomonas aeruginosa PA14, c-di-GMP inversely controls biofilm formation and surface swarming motility, with high levels of this dinucleotide signal stimulating biofilm formation and repressing swarming. P. aeruginosa encodes two stator complexes, MotAB and MotCD, that participate in the function of its single polar flagellum. Here we show that the repression of swarming motility requires a functional MotAB stator complex. Mutating the motAB genes restores swarming motility to a strain with artificially elevated levels of c-di-GMP as well as stimulates swarming in the wild-type strain, …

Steroid Receptor Isoform Expression In Drosophila Nociceptor Neurons Is Required For Normal Dendritic Arbor And Sensitivity, Aidan L. Mcparland, Taylor L. Follansbee, Gwendolyn D. Vesenka, Alexandra E. Panaitiu, Geoffrey K. Ganter

Biology Student Publications

Steroid hormones organize many aspects of development, including that of the nervous system. Steroids also play neuromodulatory and other activational roles, including regulation of sensitivity to painful stimuli in mammals. In Drosophila, ecdysteroids are the only steroid hormones, and therefore the fly represents a simplified model system in which to explore mechanisms of steroid neuromodulation of nociception. In this report, we present evidence that ecdysteroids, acting through two isoforms of their nuclear ecdysone receptor (EcR), modulate sensitivity to noxious thermal and mechanical stimuli in the fly larva. We show that EcRA and EcRB1 are expressed by third instar larvae in …

Loss Of Glycosaminoglycan Receptor Binding After Mosquito Cell Passage Reduces Chikungunya Virus Infectivity, Amber M. Paul, Dhiraj Acharya, John F. Anderson, Faqing Huang, Fengwei Bai

Publications

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that can cause fever and chronic arthritis in humans. CHIKV that is generated in mosquito or mammalian cells differs in glycosylation patterns of viral proteins, which may affect its replication and virulence. Herein, we compare replication, pathogenicity, and receptor binding of CHIKV generated in Vero cells (mammal) or C6/36 cells (mosquito) through a single passage. We demonstrate that mosquito cell derived CHIKV (CHIKVmos) has slower replication than mammalian cell derived CHIKV (CHIKVvero), when tested in both human and murine cell lines. Consistent with this, CHIKVmos infection in both cell lines produce less cytopathic …

Seeps And Springs At A Platteville “Observatory” On The River Bluffs, Bj Bonin, Greg Brick, Julia R. Steenberg

Sinkhole Conference 2015

Residential building construction along the Mississippi River bluffs in the 1970s created a unique enclosed outcrop of the Late Ordovician Platteville Formation at Lilydale, Minnesota. This outcrop was examined in early 2013 after a newly-formed spring flooded an elevator shaft the previous year, drawing attention to the foundation conditions. The Lexington Riverside property is a six story condominium complex constructed within the top of the bluff. A two-level underground parking garage was built into the bluff. Bedrock was mechanically excavated to accommodate the construction of the building, creating an unweathered rock surface. The space between the structure and the excavated …

A Tail Of Two Phages: Genomic And Functional Analysis Of Listeria Monocytogenes Phages Vb_Lmos_188 And Vb_Lmos_293 Reveal The Receptor-Binding Proteins Involved In Host Specificity, Aidan Casey, Kieran Jordan, Horst Neve, Aidan Coffey, Olivia Mcauliffe

Department of Biological Sciences Publications

The physical characteristics of bacteriophages establish them as viable candidates for downstream development of pathogen detection assays and biocontrol measures. To utilize phages for such purposes, a detailed knowledge of their host interaction mechanisms is a prerequisite. There is currently a wealth of knowledge available concerning Gram-negative phage-host interaction, but little by comparison for Gram-positive phages and Listeria phages in particular. In this research, the lytic spectrum of two recently isolated Listeria monocytogenes phages (vB_LmoS_188 and vB_LmoS_293) was determined, and the genomic basis for their observed serotype 4b/4e host-specificity was investigated using comparative genomics. The late tail genes of these …

Bacteriophages Isolated From Lake Michigan Demonstrate Broad Host-Range Across Several Bacterial Phyla, Kema Malki, Alex Kula, Katherine Bruder, Emily Sible, Thomas Hatzopoulos, Stephanie Steidel, Siobhan C. Watkins, Catherine Putonti

Biology: Faculty Publications and Other Works

BACKGROUND:

The study of bacteriophages continues to generate key information about microbial interactions in the environment. Many phenotypic characteristics of bacteriophages cannot be examined by sequencing alone, further highlighting the necessity for isolation and examination of phages from environmental samples. While much of our current knowledge base has been generated by the study of marine phages, freshwater viruses are understudied in comparison. Our group has previously conducted metagenomics-based studies samples collected from Lake Michigan - the data presented in this study relate to four phages that were extracted from the same samples.

FINDINGS:

Four phages were extracted from Lake Michigan …

Variation In Microbiome Composition And Stability For A Vancomycin Treated Primary Sclerosing Cholangitis Patient With Ulcerative Colitis Compared With Controls, Alanna Dubrovsky

Symposium

The bacterial composition of the human intestines contributes to much more than just digestion. In the inflammatory, autoimmune conditions primary sclerosing cholangitis (PSC) and ulcerative colitis (UC), the microbiome may be, in some cases, a factor. To gain a better understanding of the composition and stability of the microbiome in a patient treated with vancomycin for PSC, terminal restriction fragment (TRF) analysis was performed on 13 controls and 1 patient, and 16s rRNA microbiome composition analysis was performed on 1 patient and 3 controls. Results showed similar levels of stability, with surprising differences in composition.

Establishing Quality Control Values For Hematology Parameters: An Insight, Muhammad Shariq Shaikh

Department of Pathology and Laboratory Medicine

No abstract provided.

Isolation & Characterization Of Bacteria In The Built Environment: Measuring The Effect Of Pharmaceuticals On Growth, Amanda V. Finck, Kelly J. Digeronimo, Nene S. Sy, Zakiya Whatley

Student Publications

This work reports the isolation and characterization of bacteria from the built environment at Gettysburg College in Gettysburg, PA. Surfaces of a water fountain on campus were swabbed and serially streaked to isolate multiple bacteria on R2A agar. Following multiple rounds of growth, the unknown microbial candidates were narrowed to two visibly­distinct organisms. Morphological characterization and phylogenetic identification based on 16S rDNA sequencing revealed that the isolates were Chryseobactierum hispalense and Microbacterium maritypicum. We report synergistic biofilm formation between Chryseobactierum hispalense and Microbacterium maritypicum. The contamination of drinking water with varying levels of personal care products and pharmaceuticals (PCPPs) is …

The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai

Dissertations (1934 -)

Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …

Biophysical Properties Of Cellular Membranes In Gram-Positive Bacterial Pathogens And Their Impact On Major Physiological Attributes And Virulence Determinants, Suranjana Sen

Theses and Dissertations

The cytoplasmic membrane of bacterial cells, forming an essential barrier from the surroundings, is a critical component of cellular physiology ensuring proper survival and maintenance of major cellular functions. The integrity of the membrane is an important feature that plays an essential role in the transport of solutes and nutrients through active and passive pathways, functions of membrane-associated proteins, electron transport and ATP synthesis, maintaining turgor pressure and combating environmental stresses, and thus is a crucial factor of a majority of cellular adaptations. The various biophysical properties affecting the integrity of this membrane are mainly determined by the composition and …

Pseudomonas Bacteriophage Phi6 As A Model For Virus Emergence, Brian Elwood Ford

Dissertations, Theses, and Capstone Projects

The Pseudomonas bacteriophage Φ6 has a long and well-established history as a model organism. Here we describe a set of experiments to extend this model system to concepts previously unclaimed. Chapter 1 presents a brief background of the ecology of viruses that infect microorganisms. Chapter 2 examines genetic mutations allowing for host range expansion. Chapter 3 presents a novel paired strain assay to study how a non genetic host-acquired factor affects fitness of these enveloped viruses on subsequent hosts. Chapter 4 is an extension of this system to include how the bacteria host is affected in virus-host coevolution.