Microbiology Commons^™

Heterodimers As The Structural Unit Of The T=1 Capsid Of The Fungal Double-Stranded Rna Rosellinia Necatrix Quadrivirus 1, Daniel Luque, Carlos P. Mata, Fernando González-Camacho, José M. González, Josué Gómez-Blanco, Carlos Alfonso, Germán Rivas, Wendy M. Havens, Satoko Kanematsu, Nobuhiro Suzuki, Said A. Ghabrial, Benes L. Trus, José R Castón

Plant Pathology Faculty Publications

Most double-stranded RNA (dsRNA) viruses are transcribed and replicated in a specialized icosahedral capsid with a T=1 lattice consisting of 60 asymmetric capsid protein (CP) dimers. These capsids help to organize the viral genome and replicative complex(es). They also act as molecular sieves that isolate the virus genome from host defense mechanisms and allow the passage of nucleotides and viral transcripts. Rosellinia necatrix quadrivirus 1 (RnQV1), the type species of the family Quadriviridae, is a dsRNA fungal virus with a multipartite genome consisting of four monocistronic segments (segments 1 to 4). dsRNA-2 and dsRNA-4 encode two CPs (P2 and …

A Novel Codon-Optimized Siv Gag-Pol Immunogen For Gene-Based Vaccination, Catherine M. Crosby, Eric A. Weaver, Reeti Khare, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Simian immunodeficiency virus (SIV) is a robust pathogen used in non-human primates to model HIV vaccines. SIV encodes a number of potential vaccine targets. By far the largest and most conserved protein target in SIV is its gag-pol protein that bears many epitopes to drive multivalent immune T cell responses. While gag-pol is an attractive antigen, it is only translated after a frame shift between gag and pol with the effect that gag and pol are expressed at an approximate 10/1 ratio. The codon bias of native lentiviral genes are also mismatched with the abundance of tRNAs in mammalian cells …

Peering Below The Diffraction Limit: Robust And Specific Sorting Of Viruses With Flow Cytometry, Shea T. Lance, David J. Sukovich, Kenneth M. Stedman, Adam R. Abate

Biology Faculty Publications and Presentations

Background: Viruses are incredibly diverse organisms and impact all forms of life on Earth; however, individual virions are challenging to study due to their small size and mass, precluding almost all direct imaging or molecular analysis. Moreover, like microbes, the overwhelming majority of viruses cannot be cultured, impeding isolation, replication, and study of interesting new species. Here, we introduce PCR-activated virus sorting, a method to isolate specific viruses from a heterogeneous population. Specific sorting opens new avenues in the study of uncultivable viruses, including recovering the full genomes of viruses based on genetic fragments in metagenomes, or identifying the …

Antibacterial Activity Of Essential Oil Encapsulated Sodium Iota-Carrageenan Fibers, Carlos D. Carter

Open Access Theses

Spoilage microorganisms cause food waste and loss of quality. While the foodborne pathogen outbreaks lead to thousands of hospitalizations and deaths. Essential oils (EOs), plant extracts, possess the required antimicrobial activities and thus their usage stands out as a feasible approach for controlling the undesirable bacterial growth in food systems. However, EOs are highly volatile and lose their activity upon exposure to environmental conditions. In this regard, their encapsulation in Generally Recognized As Safe (GRAS) matrices such as food grade polysaccharides especially iota-carrageenan could be one of the viable alternatives. Iota-carrageenan, sulfated polysaccharide from marine algae, is being used in …

Genomic And Transcriptomic Analysis Of Biofilm Formation In Persistent And Transient L. Monocytogenes, Clara Assisi

Open Access Theses

The Next Generation Sequencing (NGS) has been popularized and aid in the advancement of many fields of science. The other field of science that is being revolutionized is food science and technology, especially food safety. NGS application in food safety, especially the whole genome sequencing analysis (WGS), has been widely used for tracing back the source of outbreaks. The other application of NGS that is also being developed is the analysis of global transcriptomic or RNA-sequencing (RNA-Seq). In this research, we utilize NGS (Ilumina MiSeq Sequencing platform) to perform sequence comparison and identify single nucleotide polymorphisms (SNPs) and observe the …

Recombinant Listeria Adhesion Protein Expressing Probiotics Protect Against Listeria Monocytogenes Infection In Animal Models, Valerie E. Ryan

Open Access Theses

Listeria monocytogenes (Lm) is a foodborne pathogen, found ubiquitously in nature, and has a high morbidity rate among immunocompromised individuals, the elderly, and especially pregnant women and their fetuses resulting in abortion, stillbirth, and neonatal infection. There are currently no preventative medical interventions against Lm infection. The Listeria adhesion protein (LAP) is present in both pathogenic and non-pathogenic Listeria (i.e., L. innocua) and has shown to interact with host epithelial proteins causing tight junction dysregulation aiding in pathogen attachment and paracellular translocation across the host intestinal epithelium. Our lab has demonstrated that recombinant probiotics, Lactobacillus casei (LbcWT) expressing LAP …

Utilization Of Ferrioxamine Microarrays For The Rapid Detection Of Pathogenic Bacteria, Nigam Bir Arora

Open Access Dissertations

Siderophores are low-molecular weight species utilized by bacteria for the sequestration of iron, an essential nutrient. Siderophores and their cognate receptors are considered to be virulence factors, due to their prominent role in pathogenicity. The work presented here focuses on ferrioxamine (FOx) as an “immutable” ligand for pathogen detection. A number of bacterial strains expressing high-affinity FOx receptors were identified by a proteomic BLAST search, and screened against microarrays patterned with FOx conjugates for detection using label-free optical imaging. Aspects such as inkjet printing and surface chemistry, iron-limiting conditions and bacterial selection protocols, and linker conjugate design were addressed and …

Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra

Open Access Dissertations

In alphaviruses the role of E3 is required in protecting the fusion peptide region of E1 during intracellular transport. Throughout viral processing, the association of E2 and E3 is required for the successful trafficking and incorporation of E1 into the mature virion. This E3-E2 association has been observed to extend to mature virions in the solved structure for the envelope of Semliki Forest virus (SFV) and supported by the solved structure for the entire Venezuelan equine encephalitis virion (VEEV) with exclusive contacts being made between E3-E2. Immunization with monoclonal antibodies against VEEV E3 provided protection for mice challenged by lethal …

Repurposing Non-Antimicrobial Drugs To Treat Multi-Drug Resistant Bacterial And Fungal Infections, Shankar Thangamani

Open Access Dissertations

Bacterial and fungal resistance to conventional antimicrobials is a burgeoning global health epidemic that necessitates urgent action. Even more alarming, the development of new antimicrobials to treat these multidrug-resistant pathogens has not kept pace with the rapid emergence of resistance to current antimicrobials. Antimicrobial drug development through the traditional de novo process is a risky venture given the significant financial and time investment required by researchers and limited success rate of translating these compounds to the clinical setting. This has led researchers to mine existing libraries of clinical molecules in order to repurpose old drugs for new applications (as antimicrobials). …

Massive Pulmonary Embolism Presenting As Seizures, Shahrukh Hashmani, Fateh Ali Tipoo Sultan, Murtaza Kazmi, Amammarah Yasmeen

Department of Pathology and Laboratory Medicine

Pulmonary embolism can present in various ways, though seizure activity has been rarely reported. We report a 38 years old male who had met a road traffic accident, underwent surgery, presented a month later with seizures, chest pain, shortness of breath and low blood pressure. Massive pulmonary embolism was diagnosed on CTPA, with classical features on ECG and echocardiogram and the patient was successfully managed with thrombolysis. Massive pulmonary embolism (MPE) should be kept in mind in patients who present with seizures, chest pain and haemodynamic instability.

Alternate Efflux Pump Mechanism May Contribute To Drug Resistance In Extensively Drug-Resistant Isolates Of Mycobacterium Tuberculosis, Akbar Kanji, Rumina Hasan, Ambreen Zaver, Asho Ali, Kehkashan Imtiaz, Mussarat Ashraf, Taane G. Clark, Ruth Mc Nerney, Samreen Shafiq, Zahra Hasan

Department of Pathology and Laboratory Medicine

No abstract provided.

Effect Of Time Duration Of Digestion/Decontamination Technique On Yield Of Mycobacteria And Contamination Rates From Sterile Body Fluids (Pleural And Ascitic Fluid) And Pus Specimens, Samreen Shafiq, Faryal Saleem, Kauser Jabeen, Joveria Farooqi, Warda Alam, Sadia Hanif, Shazia Ali, Sadia Shakoor, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:
Duration of digestion/decontamination has a considerable impact on yield of mycobacteria especially from sterile body fluids and pus specimens. Additionally, duration of digestion/decontamination affects the contamination rates. This study evaluates the effect of digestion/decontamination protocol for 15 and 20min versus inoculation of media directly from the sample on contamination rates as well as the yield of mycobacteria from pus and sterile fluids other than cerebrospinal fluids.
Methods:
Pleural fluid (n=60), pus (n=48) and ascitic fluid (n=12) specimens were cultured for mycobacteria and evaluated for contamination and mycobacterial yield using three different processing methodologies: without digestion/decontamination with 5% NaOH-NALC (D/D), …

Mycobacterial Contamination Of Bronchoscopes: Challenges And Possible Solutions In Low Resource Settings, Dania Khalid Saeed, Sadia Shakoor, Seema Irfan, Rumina Hasan

Department of Pathology and Laboratory Medicine

The use of bronchoscopes has increased in tuberculosis (TB) diagnostics to circumvent the diagnostic challenges that are associated with low sputum volume and smear-negative TB. In healthcare facilities situated in low income countries that have a high burden of TB, adequate decontamination of bronchoscopes is a challenge and often overlooked to save on time and costs. This amplifies the risk of outbreaks and pseudo-outbreaks due to Mycobacterium tuberculosis and nontuberculosis mycobacteria. In this minireview, we review published literature of contaminated bronchoscopes causing pseudo-outbreaks of M. tuberculosis and nontuberculosis mycobacteria in an effort to determine common sources, and possible mitigation strategies …

Pulmonary Infections After Tuberculosis, Kauser Jabeen

Department of Pathology and Laboratory Medicine

Aims and Objective: Despite effective treatment of pulmonary tuberculosis (TB) patients, destruction of lung parenchyma may lead to complications including repeated infections. These infections are often misdiagnosed or wrongly identified as TB recurrence, and hence are not treated effectively. The frequency and severity of these infections vary with the extent of damage, and are much more prominent in patients with post-TB bronchiectasis and fibrocavitary diseases. This presentation will focus on the epidemiology, treatment, and management of post-TB infections and challenges, and the impact of these infections on public health in high-TB-burden countries.
Methods: Published literature and review articles were evaluated …

Oral Microbial Burden Of Periodontal Pathogens Among Orthodontic Patients, David Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objectives

Many research studies involving orthodontic patients have a natural inclination to focus on changes in levels of cariogenic pathogens after bracket placement, and very few studies examine the role of changes of periodontal pathogens – particularly among adult patients. Interestingly, recent evidence suggests that increased levels of a specific periodontal pathogen, Fusobacterium nucleatum, may elevate risk for development of colon cancer in adults through direct pathways. Based upon this new evidence, the objective of the current study was to screen saliva samples taken from orthodontic patients to determine the prevalence of periodontal pathogens, including F. Nucleatum, T. denticola, and …

Development Of The K-State (Competence) And Mutagenesis In Stressed Bacillus Subtillis Cells, Amanda Kidman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mutagenesis is central to the evolutionary process. We currently view evolution as a gradual process affecting all cells within a population. However, my project studied an underestimated part of the evolutionary process: mutations generated during stationary phase (caused by nutritional stress or growth arrest) within a subpopulation of cells. I used Bacillus subtilis, a bacterial model for cell growth and differentiation. Stationary-phase cultures of B. subtilis differentiate subpopulations that exhibit different survival strategies including competence, secondary metabolite production, biofilm formation, cannibalism, and endospore formation. The development of competence permits cells to uptake exogenous DNA and incorporate it into their genome. …

Regulation Of Alpha-Herpesvirus Reactivation From Latency By Stress, Insun Kook

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

Bovine herpes virus 1 (BHV-1) and Herpes simplex virus 1 (HSV-1) are crucial etiological viral agent of clinical diseases. HSV-1 and BHV-1 establish latent infection in sensory neurons. Periodically, reactivation from latency occurs resulting in virus excretion and transmission. Stress increases corticosteroid levels and the incidence of HSV-1 and BHV-1 reactivation from latency. The synthetic corticosteroid, dexamethasone (DEX) mimics stress and induces BHV-1 and HSV-1 reactivation. However, molecular mechanisms by which corticosteroid mediates viral reactivation are not well understood. My dissertation has focused on elucidating events that induce BHV- 1 or HSV-1 reactivation during the early stages of stress-induced escape …

The Role Of Viral Interleukin-6 In Tumor Development Of Kaposi's Sarcoma-Associated Herpesvirus Lymphomas, Rebecca A. Fullwood

Theses and Dissertations

Kaposi's sarcoma herpesvirus (KSHV) is a cancer-causing virus, primarily affecting AIDS patients. KSHV is found in 3-10% of the U.S. population and can cause a range of cancers in the highly immunosuppressed; these cancers include Kaposi's sarcoma, pleural effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). The current techniques for treating these cancers are relatively ineffective, largely due to their inefficiency at targeting tumors formed by the infection. One protein produced by KSHV, the viral homolog of interleukin-6 (vIL-6), is thought to play a major role in tumor development post-infection. Here a novel animal model is implemented to study the …

Tuberculosis In Vulnerable Populations In Eastern Mediterranean Region-Implications For Control, Sadia Shakoor, Rumina Hasan

Department of Pathology and Laboratory Medicine

Objectives: Socially and economically disadvantaged or "vulnerable" people are at high risk of tuberculosis (TB) and also contribute to active chains of TB transmission. Included in such vulnerable populations are children, women, prisoners, people living with human immunodeficiency virus, the homeless, and displaced people. The ongoing active transmission of TB among such populations is made more difficult to assess and control by difficult access, health inequities, poverty, and other chronic and debilitating health conditions at individual, domestic, and community levels.
Methods: The 22 Eastern Mediterranean Region member states encompass diverse sociopolitical and socioeconomic situations with far-reaching effects on vulnerable populations …

The Role Of Streptococcus Gallolyticus Subspecies Gallolyticus In Colon Cancer Development, Jennifer L. Herold

Dissertations and Theses (Open Access)

Colorectal cancer (CRC) is the third most common cancer in men and women and is also the third most common cause of cancer death. A large body of evidence points towards the possibility that bacteria can have a significant impact on the development of cancer. It has been suggested that Streptococcus gallolyticus subsp. gallolyticus, a group D streptococci, may play a role in the development of CRC. Sg, formerly S. bovis biotype I, has been shown to be highly associated with CRC. In observing patients with either Sg bacteremia or endocarditis it was found that 25-80% of …

Analysis Of Nucleosome Isolation And Recovery: From In Silico Invitrosomes To In Vivo Nucleosomes, Collin Brendan Skousen

Theses and Dissertations

There are a vast number of factors that influence nucleosome formation, and consequently gene regulation. These factors include histone modifications, nucleotide composition, transcriptional region elements, and specific nucleotide motifs, among others. Although the amount we know now is limited, we are creating new techniques and discoveries to assist us in continued understanding of chromatin. To make a significant contribution to the field of chromatin, I conducted two hypothesis driven sets of experiments that address the topic of chromatin structure. First, I created a technique for tissue specific nucleosome isolation with the goal of observing the effect of single nucleotide polymorphisms …

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe-Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given …

Fecal Bacterial Communities As An Indicator Of Trophic Interactions Among Anuran Larvae, Steven Jacob Everman

Master's Theses

Anurans are mass spawners, often with multiple females spawning together, resulting in thousands of tadpoles sharing a habitat. Such large numbers of tadpoles with limited dispersal can lead to intense competition for resources. Inter and intra-specific competition for food could have negative impacts on the growth and survival of smaller tadpoles. Fecal bacterial communities have the potential to be used as indicators of changes in diet making it possible to determine if tadpoles in the wild are eating the same food or not. After feeding on two prepared diets that differed in the percentage of complex carbohydrates, the fecal bacterial …

Consensus Paper: Cerebellar Development, K Leto, M Arancillo, Ebe Becker, A Chiang, Et Al.

Faculty, Staff and Students Publications

The development of the mammalian cerebellum is orchestrated by both cell-autonomous programs and inductive environmental influences. Here, we describe the main processes of cerebellar ontogenesis, highlighting the neurogenic strategies used by developing progenitors, the genetic programs involved in cell fate specification, the progressive changes of structural organization, and some of the better-known abnormalities associated with developmental disorders of the cerebellum.

Genetic Determinants Of Salmonella And Campylobacter Required For In Vitro Fitness, Rabindra Kumar Mandal

Graduate Theses and Dissertations

Non-typhoidal Salmonella (NTS) and Campylobacter play a major role in foodborne illness caused by the consumption of food contaminated by pathogens worldwide. A comprehensive understanding of the genetic factors that increase the survival fitness of these foodborne pathogens will effectively help us formulate mitigation strategies without affecting the nutrition ecology. The objective of this study was to identify the genetic determinants of Salmonella and Campylobacter that are required for fitness under various in vitro conditions. For the purpose, we used a high throughput Transposon sequencing (Tn-seq) that utilizes next generation sequencing (NGS) to screen hundreds of thousands of mutants simultaneously. …

A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao

Graduate Theses and Dissertations

Foodborne diseases are a growing public health problem. In recent years, many rapid detection methods have been reported, but most of them are still in lab research and not practical for use in the field. In this study, a portable and automatic biosensing instrument was designed and constructed for separation and detection of target pathogens in food samples using nanobead-based magnetic separation and quantum dots (QDs)-labeled fluorescence measurement. The instrument consisted of a laptop with LabVIEW software, a data acquisition card (DAQ), a fluorescent detector, micro-pumps, stepper motors, and 3D printed tube holders. First, a sample in a syringe was …

Effects Of Acute Heat And Oxidative Stress On The Hepatic Expression Of Orexin And Its Related Receptors, Stephanie Khaldi

Graduate Theses and Dissertations

It is widely known that orexin A and B peptides as well as their receptors are expressed in the hypothalamus and distributed throughout the central nervous system, but there have been few studies regarding its presences in other parts of the body. There is now evidence that orexin (ORX) and its receptors (ORXR1/2) are present in the avian liver; however, their regulation under different environmental conditions is still unknown. In the current study, we sought to determine the effects of heat and oxidative stress using hydrogen peroxide (H2O2) and 4-hydroxynonenal (4-HNE) on the hepatic expression of ORX and ORXR1/2 in …

Visualizing A Plant Cell, Rudaba R. Hasan

The Transdisciplinary STEAM+ Journal

Why visualizing science is important, especially as a school student.

The Subject Librarian Newsletter, Biology, Fall 2016, Sandy Avila

Libraries' Newsletters

No abstract provided.

Genomes Of Gardnerella Strains Reveal An Abundance Of Prophages Within The Bladder Microbiome, Kema Malki, Jason W. Shapiro, Travis Kyle Price, Evann Elizabeth Hilt, Krystal Thomas-White, Trina Sircar, Amy B. Rosenfeld, Michael J. Zilliox, Alan J. Wolfe, Catherine Putonti

Bioinformatics Faculty Publications

Bacterial surveys of the vaginal and bladder human microbiota have revealed an abundance of many similar bacterial taxa. As the bladder was once thought to be sterile, the complex interactions between microbes within the bladder have yet to be characterized. To initiate this process, we have begun sequencing isolates, including the clinically relevant genus Gardnerella. Herein, we present the genomic sequences of four Gardnerella strains isolated from the bladders of women with symptoms of urgency urinary incontinence; these are the first Gardnerella genomes produced from this niche. Congruent to genomic characterization of Gardnerella isolates from the reproductive tract, isolates …