Organisms Commons^™

Functional And Structural Studies On The Neisseria Gonorrhoeae Gmha, The First Enzyme In The Glycero-Manno-Heptose Biosynthesis Pathways, Demonstrate A Critical Role In Lipooligosaccharide Synthesis And Gonococcal Viability, Igor H. Wierzbicki, Ryszard A. Zielke, Konstantin V. Korotkov, Aleksandra E. Sikora

Molecular and Cellular Biochemistry Faculty Publications

Sedoheptulose-7-phosphate isomerase, GmhA, is the first enzyme in the biosynthesis of nucleotide-activated-glycero-manno-heptoses and an attractive, yet underexploited, target for development of broad-spectrum antibiotics. We demonstrated that GmhA homologs in Neisseria gonorrhoeae and N. meningitidis (hereafter called GmhA_GC and GmhA_NM, respectively) were interchangeable proteins essential for lipooligosaccharide (LOS) synthesis, and their depletion had adverse effects on neisserial viability. In contrast, the Escherichia coli ortholog failed to complement GmhA_GC depletion. Furthermore, we showed that GmhA_GC is a cytoplasmic enzyme with induced expression at mid-logarithmic phase, upon iron deprivation and anaerobiosis, and conserved in contemporary gonococcal …

The Family Rhabdoviridae: Mono- And Bipartite Negative-Sense Rna Viruses With Diverse Genome Organization And Common Evolutionary Origins, Ralf G. Dietzgen, Hideki Kondo, Michael M. Goodin, Gael Kurath, Nikos Vasilakis

Plant Pathology Faculty Publications

The family Rhabdoviridae consists of mostly enveloped, bullet-shaped or bacilliform viruses with a negative-sense, single-stranded RNA genome that infect vertebrates, invertebrates or plants. This ecological diversity is reflected by the diversity and complexity of their genomes. Five canonical structural protein genes are conserved in all rhabdoviruses, but may be overprinted, overlapped or interspersed with several novel and diverse accessory genes. This review gives an overview of the characteristics and diversity of rhabdoviruses, their taxonomic classification, replication mechanism, properties of classical rhabdoviruses such as rabies virus and rhabdoviruses with complex genomes, rhabdoviruses infecting aquatic species, and plant rhabdoviruses with both mono- …

Structure Of The Chlorovirus Pbcv-1 Major Capsid Glycoprotein Determined By Combining Crystallographic And Carbohydrate Molecular Modeling Approaches, Cristina De Castro, Thomas Klose, Immacolata Speciale, Rosa Lanzetta, Antonio Molinaro, James L. Van Etten, Michael G. Rossmann

James Van Etten Publications

The glycans of the major capsid protein (Vp54) of Paramecium bursaria chlorella virus (PBCV-1) were recently described and found to be unusual. This prompted a reexamination of the previously reported Vp54 X-ray structure. A detailed description of the complete glycoprotein was achieved by combining crystallographic data with molecular modeling. The crystallographic data identified most of the monosaccharides located close to the protein backbone, but failed to detect those further from the glycosylation sites. Molecular modeling complemented this model by adding the missing monosaccharides and examined the conformational preference of the whole molecule, alone or within the crystallographic environment. Thus, combining …

Puerto Rico : Zika Virus, Rachel Cybulski

Global Public Health

Puerto Rico has had an epidemic of Zika virus within the past few years. Considering the close distance to America, the U.S. has been up-to-date in stopping the spread of Zika from Puerto Rico to the states. In 2016 particularly, the United States declared Puerto Rico to be in a state of emergency due to the heavy presence of the virus. Although this specific outbreak has been terminated, the likelihood of another such occurrence is high, so it is important to learn about the effects of Zika and ways to prevent the spread. The major result of having the virus …

Burundi : Water Scarcity, Isabel Salas

Global Public Health

Burundi is located near the African great lakes region of East Africa. This country is one of the poorest and hungriest countries throughout the world because of this they are facing multiple problems with communicable disease. These families are seeing a reduction in the amount of water available to them and based on this they are receiving water from external sources such as wells and lakes. Most of the water throughout Burundi is contaminated with Phytoplankton which increase cholera outbreaks in this area. It has also been shown that uranium impacts the water throughout the wells and lakes. Both of …

Clostridium Difficile, Ryan Osborn

Nursing Student Class Projects (Formerly MSN)

Clostridium Difficile infection (CDI) is an antibiotic resistant bacterium that is widely recognized and currently noted to be the "most common and costly healthcare associated infection in the United States" (Abt, McKenney & Pamer, 2016). The topic of CDI is important to discuss, as this infection can attack all patient populations especially those following antibiotic treatment. A disruption in a person's intestinal microbiota is known to place them at higher risk for CDI (Abt, McKenney & Pamer, 2016). Becoming infected with this bacterium leads to symptoms of diarrhea, bloating, belly pain, and occasionally fevers. The growing prevalence, antibiotic resistance associated …

An Rnai Screen To Identify Components Of A Polyamine Transport System, Adam J. Foley

Honors Undergraduate Theses

Polyamines, specifically putrescine, spermidine, and spermine, are small cationic molecules found in all organisms. Cells can biosynthetically make these molecules, or alternatively, they can be transported from the extracellular environment. Malignant cells have been shown to require relatively high amounts of polyamines. There is a chemotherapeutic agent, DFMO, used to block the biosynthesis of polyamines. Many malignant cells can circumvent DFMO therapy by activating their transport system. A potential solution is to simultaneously block biosynthesis and transport of polyamines. However, little is known about the polyamine transport system in higher eukaryotes.

This thesis aims to add to the basic biological …

Evaluation Of Flocculation, Sedimentation, And Filtration For Dewatering Of Scenedesmus Algae, Nicholas A. Rhea, Jack Groppo, Czarena Crofcheck

Biosystems and Agricultural Engineering Faculty Publications

Algae can be used as a feedstock for agricultural fertilizers, livestock and poultry feeds, anaerobic digestion, and biofuel production. For each end product, the requirements for moisture content (or solids content) vary, such that a desirable water removal strategy needs to be adaptable to varying levels of water removal. Flocculation, sedimentation, and filtration were evaluated as possible strategies for thickening and dewatering of algae. The goal of this study was to validate that algae cells treated by such means could be processed by vacuum belt filters and to determine the conditions under which the solids content could be increased to …

Conversion Of An Instantaneous Activating K+ Channel Into A Slow Activating Inward Rectifier, Dirk Baumeister, Brigitte Hertel, Indra Schroeder, Sabrina Gazzarrini, Stefan M. Kast, James L. Van Etten, Anna Moroni, Gerhard Thiel

James Van Etten Publications

The miniature channel, Kcv, is a structural equivalent of the pore of all K⁺ channels. Here, we follow up on a previous observation that a largely voltage-insensitive channel can be converted into a slow activating inward rectifier after extending the outer transmembrane domain by one Ala. This gain of rectification can be rationalized by dynamic salt bridges at the cytosolic entrance to the channel; opening is favored by voltage-sensitive formation of salt bridges and counteracted by their disruption. Such latent voltage sensitivity in the pore could be relevant for the understanding of voltage gating in complex Kv channels.

Structure Of The N-Glycans From The Chlorovirus Ne-Jv-1, Immacolata Speciale, Irina Agarkova, Garry Duncan, James L. Van Etten, Cristina De Castro

James Van Etten Publications

Results from recent studies are breaking the paradigm that all viruses depend on their host machinery to glycosylate their proteins. Chloroviruses encode several genes involved in glycan biosynthesis and some of their capsid proteins are decorated with N-linked oligosaccharides with unique features. Here we describe the elucidation of the N-glycan structure of an unusual chlorovirus, NE-JV-1, that belongs to the Pbi group. The host for NE-JV-1 is the zoochlorella Micractinium conductrix. Spectroscopic analyses established that this N-glycan consists of a core region that is conserved in all of the chloroviruses. The one difference is that the residue 3OMe-l-rhamnose is …

Structural Studies Demonstrating A Bacteriophage-Like Replication Cycle Of The Eukaryote-Infecting Paramecium Bursaria Chlorella Virus-1, Elad Milrot, Eyal Shimoni, Katya Rechav, Tamar Unger, James L. Van Etten, Abraham Minsky

James Van Etten Publications

A fundamental stage in viral infection is the internalization of viral genomes in host cells. Although extensively studied, the mechanisms and factors responsible for the genome internalization process remain poorly understood. Here we report our observations, derived from diverse imaging methods on genome internalization of the large dsDNA Paramecium bursaria chlorella virus-1 (PBCV-1). Our studies reveal that early infection stages of this eukaryotic- infecting virus occurs by a bacteriophage-like pathway, whereby PBCV-1 generates a hole in the host cell wall and ejects its dsDNA genome in a linear, base-pair-by-base-pair process, through a membrane tunnel generated by the fusion of the …

Understanding Zoonotic Enteric Disease In Minnesota: A Spatio Temporal Analysis And Causal Theory Approach, Suchismita Swain

All Graduate Theses, Dissertations, and Other Capstone Projects

With 75 percent of diseases in humans having origin in animals or animal products, zoonotic diseases have an enormous impact on the global disease burden. A significant portion of this can be attributed to bacterial zoonotic enteric pathogens. This study was designed to locate clusters of bacterial zoonotic enteric outbreaks in the State of Minnesota and study the seasonality of these outbreaks. In addition to identifying hot spots for zoonotic enteric outbreaks in Minnesota, the study also aimed to design a causal model to improve understanding of risk factors. This thesis considered only the bacterial zoonotic pathogens with significant disease …

Role Of Intracellular Growth During The Gastrointestinal Stage Of Listeria Monocytogenes Infection, Grant Steven Jones

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Listeria monocytogenes is a facultative intracellular bacterium that causes foodborne disease in humans. L. monocytogenes invade the gut mucosa and then disseminate, causing systemic infections associated with high mortality rates in immunocompromised individuals. It is unknown how L. monocytogenes traffic to the mesenteric lymph nodes, which represent an important bottleneck for systemic spread. In addition, little is known about the gastrointestinal stage of infection due to the general resistance of mice to oral infection with L. monocytogenes. Our laboratory developed a novel foodborne mouse model of listeriosis utilizing a murinized strain of L. monocytogenes to investigate the gastrointestinal stage …

Cyclic Ac253, A Novel Amylin Receptor Antagonist, Improves Cognitive Deficits In A Mouse Model Of Alzheimer’S Disease, Rania Soudy, Aarti Patel, Wen Fu, Kamaljit Kaur, David Mactavish, David Westaway, Rachel Davey, Jeffrey Zajac, Jack Jhamandas

Pharmacy Faculty Articles and Research

Introduction: Amylin receptor serves as a portal for the expression of deleterious effects of amyloid b-protein (Ab), a key pathologic hallmark of Alzheimer’s disease. Previously, we showed that AC253, an amylin receptor antagonist, is neuroprotective against Ab toxicity in vitro and abrogates Ab-induced impairment of hippocampal long-term potentiation.

Methods: Amyloid precursor protein–overexpressing TgCRND8 mice received intracerebroventricularly AC253 for 5 months. New cyclized peptide cAC253 was synthesized and administered intraperitoneally three times a week for 10 weeks in the same mouse model. Cognitive functions were monitored, and pathologic changes were quantified biochemically and immunohistochemically.

Results: AC253, when administered …

Remote Sensing Observation Of Annual Dust Cycles And Possible Causality Of Kawasaki Disease Outbreaks In Japan, Hesham El-Askary, Nick Lahaye, Erik J. Linstead, William A. Sprigg, Magdi Yacoub

Mathematics, Physics, and Computer Science Faculty Articles and Research

Kawasaki disease (KD) is a rare vascular disease that, if left untreated, can result in irreparable cardiac damage in children. While the symptoms of KD are well-known, as are best practices for treatment, the etiology of the disease and the factors contributing to KD outbreaks remain puzzling to both medical practitioners and scientists alike. Recently, a fungus known as Candida, originating in the farmlands of China, has been blamed for outbreaks in China and Japan, with the hypothesis that it can be transported over long ranges via different wind mechanisms. This paper provides evidence to understand the transport mechanisms …

Using Extremophile Bacteriophage Discovery In A Stem Education Professional Development Partnership To Explore Model Classroom Research Experiences Integrating The Three Dimentions Of The Next Generation Science Standards, Carrie L. Boudreau Ms

All Student Scholarship

The National Research Council’s (NRC) A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas describes a vision of what it means to be proficient in science. The project discussed in this thesis was developed with a NIH SEPA Grant 8R25OD010937 to the Virology and Electron Microscopy Laboratory at the University of Southern Maine (USM) under the direction of Dr. S. Monroe Duboise. The goal of the project was to explore using discovery of extreme environment bacteria and their bacteriophages as a model for using the three dimensions of learning to teach Next Generation Science Standards (NGSS). Specifically, …

Structure-Function Investigation Of Proteins Involved In Cellulose Biosynthesis By Escherichia Coli, Thomas Brenner

Theses and Dissertations (Comprehensive)

Bacteria thrive within multicellular communities called biofilms consisting of a self-produced matrix. Biofilm matrices improve bacterial adherence to surfaces while creating a barrier from host immune responses, disinfectants, antibiotics and other environmental factors. Persistent colonization by the widely distributed pathogens, Escherichia coli and Salmonella spp., has been linked to production of biofilms composed of the exopolysaccharide cellulose. Cellulose-containing biofilms are also important to Acetobacter, Sarcina, Rhizobium and Agrobacterium species to form symbiotic and pathogenic interactions. In Enterobacteriaceae, two operons (bcsABZC and bcsEFG) are proposed to encode for proteins that form a cellulose biosynthetic complex that spans the …

Taurine's Effect On Cocaine Reward And Neurogenesis In The Adolescent Male Rat Brain., Avery E. Villa-Gonzalez

Dissertations and Theses

Adolescence is a developmentally critical transition from childhood to adulthood including both maturation of the body and the brain. Neuroplastic changes result in dynamic organization of the brain during adolescence, leaving them vulnerable to development of mental illness and drug-seeking behavior. According to the United Nations Office on Drugs and Crime, the psychostimulant cocaine is the second most popular illicit drug in the world. Cocaine, amongst having many detrimental effects, has shown to also decrease hippocampal neurogenesis, resulting in decreased neuroplasticity and cognitive dysfunction. Previous students in our laboratory have shown that treatment of adult male rats with the essential …

A Systems Biology Approach For Predicting Essential Genes And Deciphering Their Dynamics Under Stress In Streptococcus Sanguinis, Fadi El-Rami

Theses and Dissertations

Infectious diseases are the top leading cause of death worldwide. Identifying essential genes, genes indispensable for survival, has been proven indispensable in defining new therapeutic targets against pathogens, major elements of the minimal set genome to be harnessed in synthetic biology, and determinants of evolutionary relationships of phylogenetically distant species. Thus, essentiality studies promise valuable revenues that can decipher much of biological complexities.

Taking advantage of the available microbial sequences and the essentiality studies conducted in various microbial models, we proposed a framework for the prediction of essential genes based on our experimentally verified knowledge of the pathways involved in …

Aedes Aegypti And Dengue In The Philippines: Centering History And Critiquing Ecological And Public Health Approaches To Mosquito-Borne Disease In The Greater Asian Pacific, Maria R. Pettis

Pomona Senior Theses

The global incidence of dengue has increase 30-fold over the past 50 years in the western or Asian Pacific, this region is also a contemporary epicenter for resource extraction and ecological destabilization. Dengue is addition to yellow fever, chikungunya and most recently zika virus, are transmitted by the mosquito vector Aedes aegypti- a domesticated mosquito adept at breeding in artificial household containers and within homes. The history of the domestication and global distribution of Aedes aegypti is intrinsically linked to European expansion into and among tropical worlds. Contemporary population genetics research suggest the westward expansion of the mosquito vector …