Microbiology Commons^™

Developmental Stage Influences Chromosome Segregation Patterns And Arrangement In The Extremely Polyploid, Giant Bacterium Epulopiscium Sp. Type B, Elizabeth Hutchison

Biology

Few studies have described chromosomal dynamics in bacterial cells with more than two complete chromosome copies or described changes with respect to development in polyploid cells. We examined the arrangement of chromosomal loci in the very large, highly polyploid, uncultivated intestinal symbiont Epulopiscium sp. type B using fluorescent in situ hybridization. We found that in new offspring, chromosome replication origins (oriCs) are arranged in a three-dimensional array throughout the cytoplasm. As development progresses, most oriCs become peripherally located. Siblings within a mother cell have similar numbers of oriCs. When chromosome orientation was assessed in situ by …

Draft Genome Sequence Of Streptomyces Sp. Strain Jv178, A Producer Of Clifednamide-Type Polycyclic Tetramate Macrolactams, Yunci Qi, John M. D’Alessandro, Joshua A.V Blodgett

Biology Faculty Research

Here, we report the draft genome sequence of Streptomyces sp. JV178, a strain originating from Connecticut (USA) garden soil. This strain produces the polycyclic tetramate macrolactam compounds clifednamides A and B. The draft genome contains 10.65 Mb, 9,045 predicted protein coding sequences, and several natural product biosynthetic loci.

Microbial Diversity In The Thermal Springs Within Hot Springs National Park, E. Taylor Stone, Richard Murray, Matthew D. Moran

Journal of the Arkansas Academy of Science

The thermal water systems of Hot Springs National Park (HSNP) in Hot Springs, Arkansas exist in relative isolation from other North American thermal systems. The HSNP waters could therefore serve as a unique center of thermophilic microbial biodiversity. However, these springs remain largely unexplored using culture-independent next generation sequencing techniques to classify species of thermophilic organisms. Additionally, HSNP has been the focus of anthropogenic development, capping and diverting the springs for use in recreational bathhouse facilities. Human modification of these springs may have impacted the structure of these bacterial communities compared to springs left in a relative natural state. The …

The Effects Of Nutrient Limitation On Toxin Production For The Harmful Algal Bloom Species, Pseudo-Nitzschia, In The Gulf Of Maine, Julia M. Park

Honors Theses

Pseudo-nitzschia is a pennate marine diatom that produces the neurotoxin domoic acid (DA). Domoic acid accumulates in the digestive tract of filter feeders and becomes concentrated at higher trophic levels. When DA concentrations reach critical levels, consumption of toxic shellfish can induce a condition known as Amnesic Shellfish Poisoning (ASP), which has been responsible for the deaths of marine mammals, seabirds and humans. This study worked to respond to a toxic Pseudo-nitzschia bloom in the Gulf of Maine during the fall of 2016, with the goal of quantifying and identifying Pseudo-nitzschia spp. in the bloom region and to determine the …

Prospective Study Of The Feasibility Of Point-Of-Care Testing Strategy For Carbapenem-Resistant Organism Detection, Rahul Pannala, Bruce Baldwin, Vijay Aluru, Thomas E. Grys, Jordan Holmes, Laurence J. Miller, M. Edwyn Harrison, Cuong C. Nguyen, Fred C. Tenover, David Persing, Douglas O. Faigel

Biology Faculty Publications

Background/aims: In an investigator-initiated, prospective study, we evaluated the feasibility of a five-gene sequence point-of-care (POC) testing strategy (Xpert CARBA-R Assay, Cepheid Inc., Sunnyvale, CA, USA), compared to reference laboratory PCR (48 – 72 hours turnaround time, two gene sequences), in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and in a hospital outbreak investigation.

Methods: After informed consent, patients undergoing ERCP (September 2015 – April 2016, n = 191) at Mayo Clinic and potential hospital contacts (n = 9) of an index carbapenem-resistant organism (CRO)-positive inpatient were included. Two rectal swabs, one each for reference and POC assays were obtained. The …

Range Expansion And The Origin Of Usa300 North American Epidemic Methicillin-Resistant Staphylococcus Aureus, Lavanya Challagundla, Isabella A. Tickler, Xavier Didelot, David C. Coleman, Anna C. Shore, Geoffrey W. Coombs, Daniel O. Sordelli, Eric L. Brown, Robert Skov, Anders Rhod Larsen, Jinnethe Reyes, Iraida E. Robledo, Guillermo J. Vazquez, Paul Rivera, Paul D. Fey, Kurt Stevenson, Shu-Hua Wang, Barry N. Kreiswirth, Jose R. Mediavilla, Cesar A. Arias, Paul J. Planet, Rathel L. Nolan, Fred C. Tenover, Richard V. Goering, D. Ashley Robinson

Biology Faculty Publications

The USA300 North American epidemic (USA300-NAE) clone of methicillin-resistant Staphylococcus aureus has caused a wave of severe skin and soft tissue infections in the United States since it emerged in the early 2000s, but its geographic origin is obscure. Here we use the population genomic signatures expected from the serial founder effects of a geographic range expansion to infer the origin of USA300-NAE and identify polymorphisms associated with its spread. Genome sequences from 357 isolates from 22 U.S. states and territories and seven other countries are compared. We observe two significant signatures of range expansion, including decreases in genetic diversity …

A Link Between Gut Microbes & Depression: Microbial Activation Of The Human Kynurenine Pathway, Christina Cobb

CMC Senior Theses

Our gut microbiota is involved in human development, nutrition, and the pathogenesis of gut disorders, but has more recently been implicated as a possible mechanism in the pathophysiology of several brain disorders, including disorders of mood and affect, such as depression. Researchers have referred to this dynamic, bidirectional signaling pathway between the gut and the brain as the “gut-brain axis.” However, most research on this axis has been limited to rodent studies, and there has been little insight into the mechanism behind it. I propose that the kynurenine pathway, where tryptophan is converted to kynurenine, is a compelling mechanism mediating …

Antibody Dependent Enhancement Of Visceral Leishmaniasis, Alan K. Mcnolty

All Master's Theses

Leishmaniasis is a parasitic disease caused by protozoans of the genus Leishmania. This vector-born disease, transmitted by biting phlebotomine sandflies, typically manifests in one of three ways. The cutaneous form of the disease is characterized by localized lesions of the skin and is by far the most common manifestation. The visceral form of the disease is caused by parasitic infiltration of internal organs, particularly the spleen, liver, and bone marrow. The mucocutaneous form is caused by parasitic infection of the mucosa in the nose or mouth. While cutaneous leishmaniasis (CL) is often self-healing, visceral leishmaniasis (VL) is fatal if …

Prospective Comparison Of Point-Of-Care Device And Standard Analyzer For Monitoring Of International Normalized Ratio In Outpatient Oral Anticoagulant Clinic, Bushra Moiz, Ahmed Raheem, Anila Rashid, Muhammad Hasan, Lena Jafri

Department of Pathology and Laboratory Medicine

Point-of-care testing (POCT) coagulometers are increasingly being used in the hospital setting and patients’ self-testing. We determined the agreement of prothrombin time international normalized ratio (INR) results by POCT coagulometer and laboratory instrument through a comparative analysis and investigated whether the results of POCT coagulometer can reliably be used without being confirmed by standard laboratory analyzer. A total of 200 INR measurements by POCT coagulometer (CoaguChek XS Pro) and laboratory analyzer (Sysmex CS2000i) were compared using Passing-Bablok regression analysis and Bland-Altman plot. Agreement of the INR measurement was further analyzed in relation to dosing decision. The correlation of INR measurements …

Microbial Community Response To Light And Heavy Crude Oil In Freshwater Systems, Timothy M. Butler

Dissertations, Master's Theses and Master's Reports

With increased demand for oil, there is an increased risk for oil spills in many environments. A number of pipelines transport oil near or across freshwater systems including the Great Lakes. Microbes are capable of breaking down oil and have thus been proposed as tools for oil spill response through bioremediation. There is a need to understand the microbial response to diverse oil types in freshwater environments due to the lack of research into this topic. This study’s main objectives are to understand how the freshwater microbial communities respond to oil, and how the bacterial communities may respond to different …

Market Integration Predicts Human Gut Microbiome Attributes Across A Gradient Of Economic Development, Keaton Stagaman, Tara J. Cepon-Robins, Melissa A. Liebert, Theresa E. Gildner, Samuel S. Urlacher, Felicia C. Madimenos, Karen Guillemin, J. Josh Snodgrass, Lawrence C. Sugiyama, Brendan J. M. Bohannan

Publications and Research

Economic development is marked by dramatic increases in the incidence of microbiome-associated diseases, such as autoimmune diseases and metabolic syndromes, but the lifestyle changes that drive alterations in the human microbiome are not known. We measured market integration as a proxy for economically related lifestyle attributes, such as ownership of specific market goods that index degree of market integration and components of traditional and nontraditional (more modern) house structure and infrastructure, and profiled the fecal microbiomes of 213 participants from a contiguous, indigenous Ecuadorian population. Despite relatively modest differences in lifestyle across the population, greater economic development correlated with significantly …

Pulmonary Alveolar Proteinosis- A Case Report, Renee M. Horner, Douglas S. Gardenhire, Ralph D. Zimmerman

Internet Journal of Allied Health Sciences and Practice

ABSTRACT

Background: Pulmonary Alveolar Proteinosis (PAP) is a rare pulmonary disorder caused by a congregation of excessive lipoproteinaceous material in the alveolar spaces due to impaired surfactant metabolism. The congregation of the protein in the alveolar space leads to difficulty in breathing, impaired pulmonary immunity, and susceptibility to both opportunistic and acquired pulmonary infections. Although Pulmonary Alveolar Proteinosis is rare, there are potential treatments. Whole-lung lavage is the most widely accepted therapy and course of treatment. An additional form of therapy, GM-CSF stimulating therapy, uses recombinant deoxyribonucleic acid (DNA) technology to increase white cell production.

Purpose: The purpose …

Genome-Wide Screening Of Potential Rnase Y-Processed Mrnas In The M49 Serotype Streptococcus Pyogenes Nz131, Zhiyun Chen, Rahul Raghavan, Fengxia Qi, Justin Merritt, Jens Kreth

Biology Faculty Publications and Presentations

RNase Y is a major endoribonuclease in Group A streptococcus (GAS) and other Gram‐positive bacteria. Our previous study showed that RNase Y was involved in mRNA degradation and processing in GAS. We hypothesized that mRNA processing regulated the expression of important GAS virulence factors via altering their mRNA stabilities and that RNase Y mediated at least some of the mRNA‐processing events. The aims of this study were to (1) identify mRNAs that were processed by RNase Y and (2) confirm the mRNA‐processing events. The transcriptomes of Streptococcus pyogenes NZ131 wild type and its RNase Y mutant (Δrny) were …

Effects Of Voluntary Physical Rehabilitation On Neurogenesis In Svz And Functional Recovery After Ischemic Stroke, Anuranjani Balakrishnan

Browse all Theses and Dissertations

Stroke is the leading cause of long-term disability and 87% of all strokes are due to ischemic strokes. In this current study, we examined whether voluntary physical rehabilitation can influence neurogenesis (measured by Doublecortin) in the subventricular zone and show improved motor functional recovery in 10-12 month female rats after ischemia. We saw a significant increase in the neurogenesis (measured by doublecortin) of all three regions (anterior, middle and posterior) of SVZ in the rehab animals compared to control group when using a two-way variance ANOVA test, although we were unable to see significant differences in paired t-tests of similar …

Size-Dependent Inhibitory Effects Of Antibiotic Drug Nanocarriers Against Pseudomonas Aeruginosa, Feng Ding, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Tao Huang, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Multidrug membrane transporters (efflux pumps) are responsible for multidrug resistance (MDR) and the low efficacy of therapeutic drugs. Noble metal nanoparticles (NPs) possess a high surface-area-to-volume ratio and size-dependent plasmonic optical properties, enabling them to serve both as imaging probes to study sized-dependent MDR and as potential drug carriers to circumvent MDR and enhance therapeutic efficacy. To this end, in this study, we synthesized three different sizes of silver nanoparticles (Ag NPs), 2.4 ± 0.7, 13.0 ± 3.1, and 92.6 ± 4.4 nm, functionalized their surface with a monolayer of 11-amino-1-undecanethiol (AUT), and covalently conjugated them with antibiotics (ofloxacin, Oflx) …

Better Living Through Chemistry: Addressing Emerging Antibiotic Resistance, Nathan P. Coussens, Ashley L. Molinaro, Kayla J. Culbertson, Tyler Peryea, Gergely Zahoránszky-Köhalmi, Matthew D. Hall, Dayle A. Daines

Biological Sciences Faculty Publications

The increasing emergence of multidrug-resistant bacteria is recognized as a major threat to human health worldwide. While the use of small molecule antibiotics has enabled many modern medical advances, it has also facilitated the development of resistant organisms. This minireview provides an overview of current small molecule drugs approved by the US Food and Drug Administration (FDA) for use in humans, the unintended consequences of antibiotic use, and the mechanisms that underlie the development of drug resistance. Promising new approaches and strategies to counter antibiotic-resistant bacteria with small molecules are highlighted. However, continued public investment in this area is critical …

Photosynthetic Activity Under Low Light, Danijela Lonco

Williams Honors College, Honors Research Projects

Are bacteria capable of undergoing oxygenic photosynthesis under low-light conditions inside of caves? Inside of an Australian cave, Chlorophyll f was recently discovered. This chlorophyll pigment was found to demonstrate the capability for photosynthesis, suggesting that Chlorophyll f extends the spectrum of usable light needed for oxygenic photosynthesis (Lars, 2015). Due to the findings in this study, a team went to Carlsbad Caverns to see if there were any bacteria capable of undergoing oxygenic photosynthesis under low light.

Investigating The Role Of Parp-1 In Hiv-1 Replication, Sara Garcia

Open Access Theses & Dissertations

Poly (ADP-ribose) Polymerase 1 (PARP-1) is a cellular protein that that has multiple roles in the cell including DNA repair and transcription. PARP-1 has also proven by our laboratory to impair HIV-1 replication in T cells infected with HIV-1 strains entering via CD4/CXCR4. The goal of my Thesis is to increase our understanding of the mechanism implicated in the anti-HIV-1 activity of PARP-1. Initially, I focused my research in deciphering the impact of PARP-1 on the replication of HIV-1 strains entering the cell through the alternative pathway CD4/CCR5. However, technical difficulties prevented answering this question. Nevertheless, aided by the technical …

Novel Therapeutic Approaches For Trypanosoma Cruzi Infection, Caresse Lynn Torres

Open Access Theses & Dissertations

Trypanosoma cruzi (T. cruzi) is the causative agent of Chagas disease (ChD), an emerging illness prevalent in South and Central America. Presently, benznidazole and nifurtimox are the only two clinically available drugs against T. cruzi, which have high toxicity and limited efficacy in the chronic phase of the disease. This ailment affects 8-10 million people and has become an emerging concern in the U.S leading to an urgent need for the discovery of new treatments. Despite all efforts, there is no human vaccine available. Therapeutic vaccines are a possible option for chronic ChD in which the vaccine is used after …

Tracking A Tree-Killer: Improving Detection And Characterizing Species Distribution Of Phytophthora Cinnamomi In Appalachian Forests, Kenton L. Sena

Theses and Dissertations--Plant and Soil Sciences

Phytophthora cinnamomi is a soil-borne oomycete pathogen causing root rot in susceptible host species. P. cinnamomi is thought to have originated in Southeast Asia, but has since been introduced to many regions around the world, where it causes dramatic declines in many forest tree species. In the eastern US, the primary susceptible tree species of concern are American chestnut (Castanea dentata), white oak (Quercus alba), and shortleaf pine (Pinus echinata). American chestnut, functionally eliminated in the early 1900s by the rapidly acting chestnut blight (Cryphonectria parasitica), has been the subject of decades-long …

The Role Of Neurokinin Receptors And Satellite Glial Cells In Herpes Simplex Virus 1 Latency, Andrew Jerome

Wayne State University Dissertations

The ability of herpes simplex virus 1 (HSV-1) to establish a lifelong infection in neurons of the trigeminal ganglion (TG) make it a constant public health threat. Viral reactivation from its latent state is currently the leading cause of viral induced blindness in the United State, as well as the leading cause of herpes simplex encephalitis. Unfortunately, how the virus is able to both establish and maintain its latent state in the TG is not well understood. The purpose of this work was to better understand how neuropeptide signaling through neurokinin receptors, as well as how satellite glial cells (SGCs) …

The Impact Of Lemongrass, Oregano, And Thyme Essential Oils On Candida Albicans' Virulence Factors, Jennifer Marie Eddins

Walden Dissertations and Doctoral Studies

Increased systemic infections and growing resistance of Candida species in immunosuppressed people have prompted research for additional treatment options. The purpose of this quantitative study was to investigate the potential of lemongrass, oregano, and thyme essential oils tested individually, combined, and combined with the antifungal agents fluconazole and caspofungin to kill Candida albicans isolates in a controlled laboratory setting. This study was grounded on the theoretical concepts of the epidemiologic triangle model. The experimental data collected were used to investigate risk factors related to age, gender, race, and comorbidities. Kill rates of lemongrass, oregano, and thyme essential oils individually and …

Hsv-1 Replication In Different Raw 264.7 And J774.1 Macrophage Phenotypes And Macrophage Viability Following Hsv-1 Infection, Yousef Nifaj Alanazi

Browse all Theses and Dissertations

HSV-1 is a ubiquitous virus capable of causing lifelong latent infection. The virus contains a large double strand DNA genome covered by an icosahedral capsid. HSV-1 is a cytolytic virus which can cause a lethal infection. The virus possesses critical protein ICP0 which is capable of interfering with host cell signaling and eventually prevent cell apoptosis. Innate immunity plays a crucial role in defense against HSV-1 infection and macrophage plays a significant role in the innate immune system. Macrophage cells can alter their behavior depending upon certain stimuli and tissue environments. Naive macrophage (M0) cells can be polarized to a …

The Impact Of Cytokines And Hsv-1 On Rab5 Protein Expression, F-Actin Cytoskeleton Rearrangement, And Cell Viability Of Uninfected And Virus-Infected M0, M1, And M2 Raw264.7 Murine Macrophages, Muhannad Falah Alruwaili

Browse all Theses and Dissertations

The endocytic pathway in all eukaryotic cells is necessary to maintain cellular functions, such as initiating transport of intracellular cargos and ingesting pathogens. The main regulator of this process is a member of small GTPase family, Rab5 protein. Rab5 protein plays a key role in the endocytic dynamic delivery of molecules, receptors, and pathogens from the cell membrane to cytoplasmic vesicles.as well as in the exocytic delivery of cellular products to the cell's exterior (Bonifacino & Glick, 2004). Many pathogens have exploited this protein to enter cells. Herpes Simplex Virus Type 1 (HSV-1) enters most cells by fusion or utilizes …

Metatranscriptome Of Human Faecal Microbial Communities In A Cohort Of Adult Men, Galeb S. Abu-Ali, Raaj S. Mehta, Jason Lloyd-Price, Himel Mallick, Tobyn Branck, Kerry L. Ivey, David A. Drew, Casey Dulong, Eric Rimm, Jacques Izard, Andrew T. Chan, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

The gut microbiome is intimately related to human health, but it is not yet known which functional activities are driven by specific microorganisms' ecological configurations or transcription. We report a large-scale investigation of 372 human fecal metatranscriptomes and 929 metagenomes from a subset of 308 men in the Health Professionals Follow-Up Study. We identified a metatranscriptomic 'core' universally transcribed over time and across participants, often by different microorganisms. In contrast to the housekeeping functions enriched in this core, a 'variable' metatranscriptome included specialized pathways that were differentially expressed both across participants and among microorganisms. Finally, longitudinal metagenomic profiles allowed ecological …

Brain Is A Potential Sanctuary For Subtype C Hiv-1 Irrespective Of Art Treatment Outcome, For Yue Tso, Guobin Kang, Eun Hee Kwon, Peter Julius, Qingsheng Li, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of …

Brain Is A Potential Sanctuary For Subtype C Hiv-1 Irrespective Of Art Treatment Outcome, For Yue Tso, Guobin Kang, Peter Julius, Qingsheng Li, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of …

Contribution Of The Gp120 V3 Loop To Envelope Glycoprotein Trimer Stability In Primate Immunodeficiency Viruses, Dane Bowder, Haley Hollingsead, Kate Durst, Duoyi Hu, Wenzhong Wei, Joshua Wiggins, Halima Medjahed, Andrés Finzi, Joseph Sodroski, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The V3 loop of the human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein (Env) becomes exposed after CD4 binding and contacts the coreceptor to mediate viral entry. Prior to CD4 engagement, a hydrophobic patch located at the tip of the V3 loop stabilizes the non-covalent association of gp120 with the Env trimer of HIV-1 subtype B strains. Here, we show that this conserved hydrophobic patch (amino acid residues 307, 309 and 317) contributes to gp120-trimer association in HIV-1 subtype C, HIV-2 and SIV. Changes that reduced the hydrophobicity of these V3 residues resulted in increased gp120 shedding and …

Ultrastructure Of Meelsvirus: A Nuclear Virus Of Arrow Worms (Phylum Chaetognatha) Producing Giant "Tailed" Virions, George L. Shinn, Brianna L. Bullard

Nebraska Center for Virology: Faculty Publications

Most known giant viruses, i.e., viruses producing giant virions, parasitize amoebae and other unicellular eukaryotes. Although they vary in the level of dependence on host nuclear functions, their virions self-assemble in the host cell's cytoplasm. Here we report the discovery of a new prototype of giant virus infecting epidermal cells of the marine arrow worm Adhesisagitta hispida. Its 1.25 μm-long virions self-assemble and accumulate in the host cell's nucleus. Conventional transmission electron microscopy reveals that the virions have a unique bipartite structure. An ovoid nucleocapsid, situated in a broad "head" end of the virion is surrounded by a thin …

Synthesis, Secretion, And Perception Of Abscisic Acid Regulates Stress Responses In Chlorella Sorokiniana, Maya Khasin, Rebecca E. Cahoon, Sophie Alvarez, Richard Beckeris, Seong-Il Eyun, Qidong Jia, Jean-Jack Riethoven, Kenneth Nickerson, Wayne R. Riekhof

Kenneth Nickerson Papers

Abscisic acid (ABA) is a phytohormone that has been extensively characterized in higher plants for its roles in seed and bud dormancy, leaf abscission, and stress responses. Genomic studies have identified orthologs for ABA-related genes throughout the Viridiplantae, including in unicellular algae; however, the role of ABA in algal physiology has not been characterized, and the existence of such a role has been a matter of dispute. In this study, we demonstrate that ABA is involved in regulating algal stress responses. Chlorella sorokiniana strain UTEX 1230 contains genes orthologous to those of higher plants which are essential for ABA …