Microbiology Commons^™

The 20th Anniversary Meeting Of The Rocky Mountain Virology Association, Joel Rovnak, Laura A. St Clair, Carley Mcalister, Chinemerem P. Ogbu, Jessica Smolenske, Randall J. Cohrs, Rushika Perera

Nebraska Center for Virology: Faculty Publications

Due to the COVID-19 pandemic and multiple devastating forest fires, the 2020 meeting of the Rocky Mountain Virology Association was held virtually. The three-day gathering featured talks describing recent advances in virology and prion research. The keynote presentation described the measles virus paradox of immune suppression and life-long immunity. Special invited speakers presented information concerning visualizing antiviral effector cell biology in mucosal tissues, uncovering the T-cell tropism of Epstein-Barr virus type 2, a history and current survey of coronavirus spike proteins, a summary of Zika virus vaccination and immunity, the innate immune response to flavivirus infections, a discussion concerning prion …

Chlorovirus Pbcv-1 Multidomain Protein A111/114r Has Three Glycosyltransferase Functions Involved In The Synthesis Of Atypical N-Glycans, Eric Noel, Anna Notaro, Immacolata Speciale, Garry A. Duncan, Cristina De Castro, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

The structures of the four N-linked glycans from the prototype chlorovirus PBCV-1 major capsid protein do not resemble any other glycans in the three domains of life. All known chloroviruses and antigenic variants (or mutants) share a unique conserved central glycan core consisting of five sugars, except for antigenic mutant virus P1L6, which has four of the five sugars. A combination of ge- netic and structural analyses indicates that the protein coded by PBCV-1 gene a111/114r, conserved in all chloroviruses, is a glycosyltransferase with three putative domains of approximately 300 amino acids each. Here, in addition to in silico sequence …

Strategies Targeting Hemagglutinin As A Universal Influenza Vaccine, Brianna L. Bullard, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Influenza virus has significant viral diversity, both through antigenic drift and shift, which makes development of a vaccine challenging. Current influenza vaccines are updated yearly to in- clude strains predicted to circulate in the upcoming influenza season, however this can lead to a mismatch which reduces vaccine efficacy. Several strategies targeting the most abundant and im- munogenic surface protein of influenza, the hemagglutinin (HA) protein, have been explored. These strategies include stalk-directed, consensus-based, and computationally derived HA immunogens. In this review, we explore vaccine strategies which utilize novel antigen design of the HA protein to improve cross-reactive immunity for development …

Zika Virus Infection Induces Endoplasmic Reticulum Stress And Apoptosis In Placental Trophoblasts, Philma Glora Muthuraj, Prakask K. Sahoo, Madison Kraus, Taylor Bruett, Arun S. Annamalai, Aryamav Pattnaik, Asit K. Pattnaik, Siddappa N. Byrareddy, Sathish Kumar Natarajan

Nebraska Center for Virology: Faculty Publications

Zika virus (ZIKV) infection to a pregnant woman can be vertically transmitted to the fetus via the placenta leading to Congenital Zika syndrome. This is characterized by microcephaly, retinal defects, and intrauterine growth retardation. ZIKV induces placental trophoblast apoptosis leading to severe abnormalities in the growth and development of the fetus. However, the molecular mechanism behind ZIKV-induced apoptosis in placental trophoblasts remains unclear. We hypothesize that ZIKV infection induces endoplasmic reticulum (ER) stress in the trophoblasts, and sustained ER stress results in apoptosis. HTR-8 (HTR-8/SVneo), a human normal immortalized trophoblast cell and human choriocarcinoma-derived cell lines (JEG-3 and JAR) were …

Covid19 Disease Map, A Computational Knowledge Repository Of Virus–Host Interaction Mechanisms, Marek Ostaszewski, Tomáš Helikar, Bhanwar Lal Puniya, A Host Of Co-Authors, Covid-19 Disease Map Community

Department of Biochemistry: Faculty Publications

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, …

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 …

Pseudomonas Aeruginosa Vaccine Development Using Dual-Species Whole Cell And Subunit Vaccines, Catherine Bell Blackwood

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen which can cause severe, recurrent, and chronic infections. The pathogen is highly adaptable, and pneumonia caused by it is associated with high morbidity and mortality, especially in individuals with the genetic disorder cystic fibrosis. Antibiotic resistance amongst clinical isolates of P. aeruginosa is steadily increasing, and multi-drug resistant strains are prevalent. There is currently no vaccine available for commercial use against P. aeruginosa. For these reasons, we sought to understand the immunity to P. aeruginosa induced by whole cell vaccination and identify antigens for development of future subunit vaccines. In this dissertation, …

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 …

Applied Molecular Dynamics: From Targeting Viral Helicases, To Understanding The Interactions Of Cucurbituril Complexes In Ionic Solutions, Bryan Raubenolt

LSU New Orleans Theses and Dissertations

Molecular Dynamics simulations are a highly useful tool in helping understand the fundamental interactions present in a variety of chemical systems. The work discussed here illustrates it’s use in determining the conformational dynamics of the Zika and SARS-Cov-2 helicase in a physiological environment, largely in an effort to discover inhibitors capable of rendering the protein inert. Additionally, we show how it can be used to understand paradoxical trends in the anion-induced precipitation of Cucurbituril cavitands.

Viral helicases are motor proteins tasked with unwinding the viral dsRNA, a crucial step in preparing the strand to be translatable by host cells. By …

Inaction On Lead Despite The Relevant Knowledge: Predictors, Covariates, And Outreach Implications, Alessandra Rossi, Bernabas Wolde, Pankaj Lal, Melissa Harclerode

Department of Biology Faculty Scholarship and Creative Works

Testing residential soil and paint for lead provides actionable information. By showing where and how much lead exists on the residence, it allows one to quantify risk and determine the best ways to reduce exposure along with the corresponding health and financial costs. For these reasons, several federal and state programs offer outreach to audiences on the benefits of testing residential soil and paint for lead. Not all individuals who know about lead’s adverse health effects, however, test their residence for lead, potentially limiting the actionable information that could have helped to reduce their exposure. Such individuals represent a challenge …

Pandemic Vibrio Cholerae Shuts Down Site-Specific Recombination To Retain An Interbacterial Defence Mechanism, Francis J. Santoriello, Lina Michel, Daniel Unterweger, Stefan Pukatzki

Publications and Research

Vibrio cholerae is an aquatic microbe that can be divided into three subtypes: harmless environmental strains, localised pathogenic strains, and pandemic strains causing global cholera outbreaks. Each type has a contact-dependent type VI secretion system (T6SS) that kills neighbouring competitors by translocating unique toxic effector proteins. Pandemic isolates possess identical effectors, indicating that T6SS effectors may affect pandemicity. Here, we show that one of the T6SS gene clusters (Aux3) exists in two states: a mobile, prophage-like element in a small subset of environmental strains, and a truncated Aux3 unique to and conserved in pandemic isolates. Environmental Aux3 can be readily …

Impact Of Endangered Animal Protection Rights, Policies, And Practices On Zoonotic Disease Spread, Daniella Fedak-Lengel

Honors Projects

Building on field research in Costa Rica and Belize, this honors project analyzes environmental and endangered animal protection policies, rights, and practices in Central America and the Caribbean, and assesses the impact of veterinary science and biological research and practice, particularly conservation biology, on animal welfare concerns. Informed by the recent surge in awareness regarding zoonoses and zoonotic disease transmission, prevention and control, resulting from the current global pandemic of SARS-CoV-2, the project assesses the need for new and innovative types of collaboration, particularly involving conservation biologists, environmental scientists, public health experts, law and policy makers, and global trade and …

Study Of Plants Used Against Infections By California Native American Tribes, Maria J. Rojas

Master's Theses

The objectives of this research were to evaluate the antibacterial activity and to determine the chemical composition of a list of medicinal plants used by Native Americans in California. Artemisia californica, Mimulus aurantiacus, Equisetum telmateia, Equisetum hyemale, and Marah fabacea were selected from a list of plants reported as having been used for ailments related to infections by tribes located in California. The extracts obtained through steam distillation from E. telmateia, E. hyemale and M. fabacea were assayed for in vitro antibacterial activity against 16 Gram-negative and 6 Gram-positive bacteria using disk diffusion assays and measuring the diameters of inhibition …

Role Of Β-Glucan Structure In Dectin-1 Homo- And Hetero-Oligomerization In Innate Anti-Fungal Immunity, Eduardo U. Anaya

Biomedical Sciences ETDs

Dectin-1A is a C-type Lectin innate immunoreceptor that recognizes β-(1,3)-glucan, a structural component of Candida species cell walls. Dectin-1 has eight alternative splice isoforms including, A and B. Innate immunocytes can express one or both isoforms, but neither their relative responsiveness to β-glucan nor the potential for inter-isoform signaling cross-talk is well understood. In this study, we determine how the different structures of soluble β-glucans affect both isoforms and unravel how differences in glucan structure impact the earliest events in Dectin-1 signaling. Using quantitative microscopy techniques, we explored the role of glucan structure on Dectin-1A oligomerization, which is thought to …

Exploring The Niche Of Rickettsia Montanensis (Rickettsiales: Rickettsiaceae) Infection Of The American Dog Tick (Acari: Ixodidae), Using Multiple Species Distribution Model Approaches, Catherine A. Lippi, Holly Gaff, Alexis L. White, Heidi K. St. John, Allen L. Richards, Sadie J. Ryan

Biological Sciences Faculty Publications

The American dog tick, Dermacentor variabilis (Say) (Acari: Ixodidae), is a vector for several human diseasecausing pathogens such as tularemia, Rocky Mountain spotted fever, and the understudied spotted fever group rickettsiae (SFGR) infection caused by Rickettsia montanensis. It is important for public health planning and intervention to understand the distribution of this tick and pathogen encounter risk. Risk is often described in terms of vector distribution, but greatest risk may be concentrated where more vectors are positive for a given pathogen. When assessing species distributions, the choice of modeling framework and spatial layers used to make predictions are important. …

Examining Pathogenesis And Preventatives In Spontaneous And Staphylococcus-Induced Bacterial Chondronecrosis With Osteomyelitis In Broilers, Nnamdi Simon Ekesi

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis is the most important cause of lameness in broilers. This is important to poultry production, as it poses animal welfare issues, and causes a significant loss in revenue. The remediation of this disease requires the study of its etiology with fitting models and evaluating preventatives. The research reported herein covers genomic virulence analysis of BCO isolates, mainly Staphylococcus aureus, and Escherichia coli retrieved from lame birds. We found that S. aureus isolates were closest to chicken strains in Europe but may have been in the Arkansas area for a decade. Phylogenomics suggest our S. aureus is …

Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai

Graduate Theses and Dissertations

Bovine respiratory disease (BRD) is the most common and costly disease in the beef cattle industry, leading to high morbidity, mortality and huge economic loss. Despite the recent advances in vaccination and antimicrobial techniques, no significant health-improved outcomes have developed. Due to a deep investigation of the microbiome, respiratory microbiotas are known to have important roles for host health and disease. However, BRD specific pathogens have not yet been identified since they are found in both healthy and diseased animals. A systemic and comprehensive study of the biogeography of the bovine respiratory microbiome and its relationship with BRD is lacking …

Acute Ischemic Stroke As The Presenting Feature Of Covid-19 In The Young And Pregnant, Nermila A. Ballmick, Jiri F. Kubac, Hossein Akhondi

HCA Healthcare Journal of Medicine

Introduction: Coronavirus disease (COVID-19) is an emerging and rapidly evolving public health issue that has become globally widespread and an overwhelming pandemic. Clinical manifestations of the disease include asymptomatic carrier states, acute respiratory distress syndrome, and even multiorgan dysfunction. Here, we present a unique and rare case of an acute ischemic stroke (AIS) in an asymptomatic pregnant woman with no predisposing medical illnesses.

Discussion: An 18-year-old G2P1 African American woman at 7 weeks gestational age with no significant medical or family history presenting to the Emergency Department during the initial phases of the pandemic with complaints of new onset left …

A Microbiome Analysis Of The Relationship Among Crayfish Ectosymbionts And Their Environment, John Hoverson

Senior Honors Theses

The purpose of this project was to determine if there are differences present between the α-diversities of the crayfish microbiome and its surrounding water and sediment. Furthermore, this project sought to discover if these differences hold when microbiomes are evaluated between crayfish of first and second stream orders. Finally, this project sought to determine if the presence of branchiobdellidan ectosymbionts on the crayfish caused further differences in the crayfish microbiome. While the hypothesized patterns between crayfish, ectosymbionts, and stream order were not found to exist, a significantly different microbiome was observed between water, sediment, and crayfish, and the α-diversity of …

Increasing Antibiotic Resistance In Shigella Bacteria In The United States, William J. Pharr

The Corinthian

Shigella bacteria cause half a million infections, 6,000 hospitalizations, and 70 deaths annually in the United States. These bacteria are of particular concern due to their high survivability, low infectious dose, and high adaptability. Cases of shigellosis from Shigella sonnei are becoming a more prevalent issue in the U.S. as the bacteria continues to develop higher resistance to today’s strongest antibiotics. Much of this resistance is connected to the exchange of genes between strains of Shigella due to insertion sequences (IS), intercontinental travel, and men who have sex with men (MSM). As a result of increased resistance, the use of …

Spatial And Temporal Determinants Associated With Eastern Equine Encephalitis Virus Activity In Florida, Kristi M. Miley

USF Tampa Graduate Theses and Dissertations

Eastern Equine Encephalitis virus (EEEV) is considered the most pathogenic mosquito-borne illness in the United States. Human mortality has been estimated to range between 35 to 75%, with horses experiencing mortality rates greater than 90%. A large number of EEEV cases occur in Florida. Though we have come a long way since the first human infection was identified in the 1930s, there is still much to learn regarding the virus’s ability to maintain transmission year-round in Florida. Phylogenic studies support that Florida may serve as the geographic reservoir for EEEV. This research investigated spatiotemporal and ecological variables associated with risk …

Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Clostridioides difficile is recognized as one of the most important pathogens in hospital and community healthcare settings. The clinical outcome of infection of toxigenic C. difficile infection (CDI) ranges from asymptomatic colonization to fulminant pseudomembranous colitis and death. In recent studies, it has been suggested that a high proportion of nosocomial CDI cases are transmitted from asymptomatic carriers which might be acting as infection reservoirs. Understanding what causes the different responses to infection could lead to the development of novel prevention and treatment strategies. Although several explanations have been proposed to explain variations in susceptibility, understanding of the exact mechanisms …

Evaluating The Microbial Experience Influence On Anti-Tumor Immune Response, Jessica A. Ensing

Student Summer Scholars Manuscripts

Despite the steady increase of hygienic standards, the CDC continues to report an increase of immune-mediated diseases such as allergies and asthma. Human avoidance of microbial exposure and subsequently less experienced immune systems may be the cause for this increase. We investigated if increased microbial exposure results in increased immunity to cancer (B16 melanoma) by measuring activated lymphocytes between two groups of C57Bl/6 mice: specific pathogen free (SPF) mice (which had little microbial exposure) and cohoused (COH) mice (which were exposed to numerous microbes). Previous research shows that the CoH mouse model mimics a human adult’s immune system, while the …

Evaluation Of Semi-Quantitative Compared To Quantitative Cultures Of Tracheal Aspirates For The Yield Of Culturable Respiratory Pathogens - A Cross-Sectional Study, Salima Rattani, Joveria Farooqi, Ghazala Jabeen, Saeeda Chandio, Qaiser Kash, Aijaz Khan, Kauser Jabeen

Department of Pathology and Laboratory Medicine

Background: Diagnosis of lower respiratory tract infections (LRTI) depends on the presence of clinical, radiological and microbiological findings. Endotracheal suction aspirate (ETSA) is the commonest respiratory sample sent for culture from intubated patients. Very few studies have compared quantitative and semi-quantitative processing of ETSA cultures for LRTI diagnosis. We determined the diagnostic accuracy of quantitative and semi-quantitative ETSA culture for LRTI diagnosis, agreement between the quantitative and semi quantitative culture techniques and the yield of respiratory pathogens with both methods.
Methods: This was a cross-sectional study conducted at the Aga Khan University clinical laboratory, Karachi, Pakistan. One hundred and seventy-eight …

Cryo‑Electron Microscopy Structure Of The 70s Ribosome From Enterococcus Faecalis, Eileen L. Murphy, Kavindra V. Singh, Bryant Avila, Torsten Kleffmann, Steven T. Gregory, Barbara E. Murray, Kurt L. Krause, Reza Khayat, Gerwald Jogl

Publications and Research

Enterococcus faecalis is a gram-positive organism responsible for serious infections in humans, but as with many bacterial pathogens, resistance has rendered a number of commonly used antibiotics ineffective. Here, we report the cryo-EM structure of the E. faecalis 70S ribosome to a global resolution of 2.8 Å. Structural differences are clustered in peripheral and solvent exposed regions when compared with Escherichia coli, whereas functional centres, including antibiotic binding sites, are similar to other bacterial ribosomes. Comparison of intersubunit conformations among five classes obtained after three-dimensional classification identifies several rotated states. Large ribosomal subunit protein bL31, which forms intersubunit bridges to …

Microbial Diversity In The Sawmill Environment: Implications On The Health Of Sawmill Workers And Merchants, Nigeria, Ebere J. Okafor-Elenwo Ej, Odaro S. Imade Os, Osazee E. Izevbuwa Eo

Journal of Bioresource Management

There is an increasingly high suspicion of occupational health diseases amongst workers in sawmill factories. Hence this study aimed to determine the microbial diversity in some sawmill factories in Okada, Edo State, Nigeria to evaluate potential implications of the factory’s processing area on the health of the workers and wood merchants. Bacteria and fungi count in the bioaerosols within the processing area of each factory was performed with the passive air sampling technique. While in the sawdust samples, microbial counts were carried out with the pour plate technique. Identification of the microbes was performed with macroscopic and microscopic examinations as …

A Functional K+ Channel From Tetraselmis Virus 1, A Member Of The Mimiviridae, Kerri Kukovetz, Brigitte Hertel, Christopher R. Schvarcz, Andrea Saponaro, Mirja Manthey, Ulrike Burk, Timo Greiner, Grieg F. Steward, James L. Van Etten, Anna Moroni, Gerhard Thiel, Oliver Rauh

Nebraska Center for Virology: Faculty Publications

Potassium ion (K+) channels have been observed in diverse viruses that infect eukaryotic marine and freshwater algae. However, experimental evidence for functional K+ channels among these alga-infecting viruses has thus far been restricted to members of the family Phycodnaviridae, which are large, double-stranded DNA viruses within the phylum Nucleocytoviricota. Recent sequencing projects revealed that alga-infecting members of Mimiviridae, another family within this phylum, may also contain genes encoding K+ channels. Here we examine the structural features and the functional properties of putative K+ channels from four cultivated members of Mimiviridae. While all four proteins contain variations …

Biofilm Forming Ability Of Bacteria Isolated From Dental Caries: With Reference To Streptococcus Species, Sonali Kaustubh Ambulkar, Vidya Tale, Abhijit Jadhav, Komal Kulkarni

Future Dental Journal

Dental caries is formed by the group of microorganisms attached to a tooth surface embedded in a matrix of polymers. Biofilm plays an important role in the development of dental caries, plaque and other periodontal diseases. The present study is aimed to isolate, identify and characterize bacteria from dental caries. The ability of biofilm formation of these isolates was confirmed by Congo red agar method, Tube method and Microtitre plate method. High biofilm-forming bacteria were identified by 16S rRNA sequencing. Streptococcus mutans, Streptococcus anginosus, Enterococcus faecalis and Rothia dentocariosa are the predominant biofilm forming bacteria associated with dental caries.

Mechanism Of Translation Inhibition By Type Ii Gnat Toxin Atat2, Stepan V Ovchinnikov, Dmitry Bikmetov, Alexei Livenskyi, Marina Serebryakova, Brendan Wilcox, Kyle Mangano, Dmitrii I Shiriaev, Ilya A Osterman, Petr V Sergiev, Sergei Borukhov, Nora Vazquez-Laslop, Alexander S Mankin, Konstantin Severinov, Svetlana Dubiley

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Type II toxin-antitoxins systems are widespread in prokaryotic genomes. Typically, they comprise two proteins, a toxin, and an antitoxin, encoded by adjacent genes and forming a complex in which the enzymatic activity of the toxin is inhibited. Under stress conditions, the antitoxin is degraded liberating the active toxin. Though thousands of various toxin-antitoxins pairs have been predicted bioinformatically, only a handful has been thoroughly characterized. Here, we describe the AtaT2 toxin from a toxin-antitoxin system from Escherichia coli O157:H7. We show that AtaT2 is the first GNAT (Gcn5-related N-acetyltransferase) toxin that specifically targets charged glycyl tRNA. In vivo, the AtaT2 …

Defining The Proteolytic Landscape During Enterovirus Infection., Mohsan Saeed, Sebastian Kapell, Nicholas T Hertz, Xianfang Wu, Kierstin Bell, Alison W Ashbrook, Milica Tesic Mark, Henry A Zebroski, Maxwell L Neal, Malin Flodström-Tullberg, Margaret R Macdonald, John D Aitchison, Henrik Molina, Charles M Rice

Articles, Abstracts, and Reports

Viruses cleave cellular proteins to remodel the host proteome. The study of these cleavages has revealed mechanisms of immune evasion, resource exploitation, and pathogenesis. However, the full extent of virus-induced proteolysis in infected cells is unknown, mainly because until recently the technology for a global view of proteolysis within cells was lacking. Here, we report the first comprehensive catalog of proteins cleaved upon enterovirus infection and identify the sites within proteins where the cleavages occur. We employed multiple strategies to confirm protein cleavages and assigned them to one of the two enteroviral proteases. Detailed characterization of one substrate, LSM14A, a …