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Articles 1 - 30 of 447

Full-Text Articles in Pathogenic Microbiology

Lipoarabinomannan From Mycobacterium Smegmatis Stimulates An Inflammatory Response In Raw 264.7 Murine Macrophages, Aysha Zaman Apr 2019

Lipoarabinomannan From Mycobacterium Smegmatis Stimulates An Inflammatory Response In Raw 264.7 Murine Macrophages, Aysha Zaman

Student Scholar Showcase

Macrophages are a key leukocyte in defense against Mycobacterium tuberculosis infection. The precise mechanism by which M. tuberculosis evades host macrophage defenses remains unknown, so understanding how macrophages interact with cell wall components of mycobacteria is critical. Lipoarabinomannan (LAM) is a glycolipid Toll-like receptor-2 (TLR-2) ligand found on the cell wall of mycobacteria, and is thought to contribute to the cell wall structural integrity. When LAM binds to TLR on host leukocytes, this activates cellular responses and phagocytosis by host macrophages. Nitric oxide production can be used as a measure of inflammatory response and can be evaluated via nitrite response ...


Does Quorum Sensing Regulate The Conjugation Of The Two Co-Resident Megaplasmids Of Agrobacterium Tumefaciens 15955, Christopher Carter Apr 2019

Does Quorum Sensing Regulate The Conjugation Of The Two Co-Resident Megaplasmids Of Agrobacterium Tumefaciens 15955, Christopher Carter

Kansas State University Undergraduate Research Conference

While the effects of Agrobacterium tumefaciens can be easily observed and have been studied closely, the mechanisms for their virulence habits have not. Several studies have suggested the mechanisms for plasmid transfer and conjugation, particularly concerning plasmid Ti (pTi), the TraR (TraR1) regulator, and the quorum sensing (QS) system associated with it. Very little is known, however, about the second plasmid (pAt) present within the bacteria nor its regulatory QS systems. To further understand these mechanics of plasmid conjugation, we have devised a series of experiments in order to find connections between the conjugation of both pTi and pAt and ...


Assessment Of The Potential Use Of Recombinant Baculovirus-Expressed Lassa Virus Nucleoprotein As A Serodiagnostic Antigen, Sahiba Grover Apr 2019

Assessment Of The Potential Use Of Recombinant Baculovirus-Expressed Lassa Virus Nucleoprotein As A Serodiagnostic Antigen, Sahiba Grover

Kansas State University Undergraduate Research Conference

Lassa virus is an arenavirus causing a disseminated systemic primary viral infection. This virus causes Lassa fever which is a viral hemorrhagic fever endemic in West Africa and is responsible for the deaths of thousands of people each year. There is a possibility for the Lassa virus to be introduced into the US and used as a biological weapon with the potential to harm a large-scale population. Because of increasing international travel, a sizeable burden from the disease, and its potential use for biological warfare, it is necessary to develop sensitive diagnostic assays to accurately detect virus infections and mitigate ...


Determining The Role Of Cdr20291_0493 Sporulation Initiation In Clostridium Difficile, Carolina Bueno Apr 2019

Determining The Role Of Cdr20291_0493 Sporulation Initiation In Clostridium Difficile, Carolina Bueno

Kansas State University Undergraduate Research Conference

Our lab focuses on the gene regulatory networks of Clostridium difficilesporulation and toxins virulence factors. Spores are the major reason of the disease transmission; this is why it is important to understand how this spores are formed so drugs can be targeted to formation. Our objective is to identify the gene regulatory networks that control sporulation. The candidate target gene we are studying is CDR20291_0493 in C. difficileR20291 strain. We want to understand the role of this gene in sporulation initiation of C.difficile. We first created a mutant of CDR20291_0493 mutant R20291Dto look for sporulation phenotype and ...


Interferon-Induced Transmembrane Protein 3 Blocks Fusion Of Sensitive But Not Resistant Viruses By Partitioning Into Virus-Carrying Endosomes, Krishna C. Suddala, Christine C. Lee, Paul Meraner, Mariana Marin, Ruben M. Markosyan, Tanay M. Desai, Fredric S. Cohen, Abraham L. Brass, Gregory B. Melikyan Jan 2019

Interferon-Induced Transmembrane Protein 3 Blocks Fusion Of Sensitive But Not Resistant Viruses By Partitioning Into Virus-Carrying Endosomes, Krishna C. Suddala, Christine C. Lee, Paul Meraner, Mariana Marin, Ruben M. Markosyan, Tanay M. Desai, Fredric S. Cohen, Abraham L. Brass, Gregory B. Melikyan

Open Access Articles

Late endosome-resident interferon-induced transmembrane protein 3 (IFITM3) inhibits fusion of diverse viruses, including Influenza A virus (IAV), by a poorly understood mechanism. Despite the broad antiviral activity of IFITM3, viruses like Lassa virus (LASV), are fully resistant to its inhibitory effects. It is currently unclear whether resistance arises from a highly efficient fusion machinery that is capable of overcoming IFITM3 restriction or the ability to enter from cellular sites devoid of this factor. Here, we constructed and validated a functional IFITM3 tagged with EGFP or other fluorescent proteins. This breakthrough allowed live cell imaging of virus co-trafficking and fusion with ...


Nascent Dna Proteomics Analysis Uncovers Dna Replication Dynamics In The Human Pathogen Trypanosoma Brucei, Maria Rocha Granados Jan 2019

Nascent Dna Proteomics Analysis Uncovers Dna Replication Dynamics In The Human Pathogen Trypanosoma Brucei, Maria Rocha Granados

Doctoral Dissertations

DNA is the substrate of many cellular processes including DNA replication, transcription and chromatin remodeling. These processes are coordinated to maintain genome integrity and ensure accurate duplication of genetic and epigenetic information. Genome-wide studies have provided evidence of the relationship between transcription and DNA replication timing. A global analysis of DNA replication initiation in T. brucei showed that TbORC1 (subunit of the origin recognition complex, ORC) binding sites are located at the boundaries of transcription units. Although recent studies in T. brucei indicate functional links among DNA replication and transcription, the underlying mechanisms remain unknown. In this study, we adapted ...


Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey Jan 2019

Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey

Undergraduate Honors Theses

The microbial community of amphibians skin has demonstrated significant importance in amphibian health and disease resistance specifically in response to the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd; Barnhart et al. 2017). Since its discovery in the late 1990s, Bd has contributed to world-wide decline in amphibian populations. Multiple naturally occurring amphibian-skin bacteria have been identified as inhibitors of Bd, including Janthinobacterium lividum (J liv; Harris et al. 2009). The McKenzie group developed a probiotic treatment of J liv as an intervention for a boreal toad population in Colorado drastically declining due to a Bd epidemic. Since wild toads cannot be ...


Antibiotic Resistance Coming Soon To A Pathogen Near You, Mckenzie Altman, Tamia Mills, Lindsey Layman, Catherine Stone Dec 2018

Antibiotic Resistance Coming Soon To A Pathogen Near You, Mckenzie Altman, Tamia Mills, Lindsey Layman, Catherine Stone

Undergraduate Research Symposium (URS)

The phenomena of antibiotic resistant bacteria has increased worldwide and can frequently be found on everyday surfaces. Here, we characterize a bacterial isolate from a woman’s restroom door handle at Marian. Preliminary results comprised of morphological and biochemical tests, including growth characteristics on blood agar medium, as well as usage of the Kirby Bauer agar diffusion test to determine antibiotic susceptibility, identifies this isolate to be a multidrug resistant Neisseria species. However, additional detailed analysis is needed to confirm its identity.


Aqueous Ozone Inactivation Of Viruses And Bacteria On Biotic And Abiotic Surfaces, Cailin Dawley Dec 2018

Aqueous Ozone Inactivation Of Viruses And Bacteria On Biotic And Abiotic Surfaces, Cailin Dawley

Theses and Dissertations

Produce is susceptible to contamination by foodborne pathogens. Food service establishments utilize sanitizing agents to reduce microbes on produce surfaces. The research objectives were to evaluate the efficacy of aqueous ozone 1) on the inactivation of viruses and bacteria on produce; 2) on the inactivation of viruses on stainless steel; and 3) against viruses in association with bacteria on produce surfaces. For objective 1, Boston bibb lettuce and cherry tomatoes were spot inoculated with a cocktail of viruses (murine norovirus (MNV) and MS2 bacteriophage) or bacteria (Enterobacter cloacae and Bacillus cereus) and washed for 40 min with samples taken every ...


Bacterial Abundance And Resistance In Ground Beef Varieties, Savannah Kumar, Sarah M. Boomer Nov 2018

Bacterial Abundance And Resistance In Ground Beef Varieties, Savannah Kumar, Sarah M. Boomer

PURE Insights

Raw ground beef purchased at supermarkets across America have one thing in common: they harbor bacteria, some of which are drug resistant and can be detrimental to public health. To understand the impact of farming and processing practices on the quantity of bacteria and drug resistance, organic and regular beef were assessed using MacConkey media. Bacterial colonies were sorted according to lactose utilization, with positive colonies representing fecal E. coli. Lactose negative colonies were further characterized into one of two groups (fecal Hafnia-like or soil Pseudomonas) using a variety of metabolic tests (oxidase, sulfur, indole). Advanced metabolic testing showed that ...


Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge Nov 2018

Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge

Open Access Articles

Chitin is an essential component of the cell wall of Cryptococcus neoformans conferring structural rigidity and integrity under diverse environmental conditions. Chitin deacetylase genes encode the enyzmes (chitin deacetylases [Cdas]) that deacetylate chitin, converting it to chitosan. The functional role of chitosan in the fungal cell wall is not well defined, but it is an important virulence determinant of C. neoformans Mutant strains deficient in chitosan are completely avirulent in a mouse pulmonary infection model. C. neoformans carries genes that encode three Cdas (Cda1, Cda2, and Cda3) that appear to be functionally redundant in cells grown under vegetative conditions. Here ...


Deciphering The Molecular Basis Of Mycobacteria And Lipoglycan Recognition By The C-Type Lectin Dectin-2, Alexiane Decout, Devinder Kaur, Jerome Nigou Nov 2018

Deciphering The Molecular Basis Of Mycobacteria And Lipoglycan Recognition By The C-Type Lectin Dectin-2, Alexiane Decout, Devinder Kaur, Jerome Nigou

Open Access Articles

Dectin-2 is a C-type lectin involved in the recognition of several pathogens such as Aspergillus fumigatus, Candida albicans, Schistosoma mansonii, and Mycobacterium tuberculosis that triggers Th17 immune responses. Identifying pathogen ligands and understanding the molecular basis of their recognition is one of the current challenges. Purified M. tuberculosis mannose-capped lipoarabinomannan (ManLAM) was shown to induce signaling via Dectin-2, an activity that requires the (alpha1 --> 2)-linked mannosides forming the caps. Here, using isogenic M. tuberculosis mutant strains, we demonstrate that ManLAM is a bona fide and actually the sole ligand mediating bacilli recognition by Dectin-2, although M. tuberculosis produces a ...


Characterization Of Tick Organic Anion Transporting Polypeptides (Oatps) Upon Bacterial And Viral Infections, Vikas Taank, Wenshou Zhou, Xuran Zhuang, John F. Anderson, Utpal Pal, Hameeda Sultana, Girish Neelakanta Nov 2018

Characterization Of Tick Organic Anion Transporting Polypeptides (Oatps) Upon Bacterial And Viral Infections, Vikas Taank, Wenshou Zhou, Xuran Zhuang, John F. Anderson, Utpal Pal, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Background: Ixodes scapularis organic anion transporting polypeptides (OATPs) play important roles in tickrickettsial pathogen interactions. In this report, we characterized the role of these conserved molecules in ticks infected with either Lyme disease agent Borrelia burgdorferi or tick-borne Langat virus (LGTV), a pathogen closely related to tick-borne encephalitis virus (TBEV).

Results: Quantitative real-time polymerase chain reaction analysis revealed no significant changes in oatps gene expression upon infection with B. burgdorferi in unfed ticks. Synchronous infection of unfed nymphal ticks with LGTV in vitro revealed no significant changes in oatps gene expression. However, expression of specific oatps was significantly downregulated upon ...


Vancomycin Delays Clindamycin-Induced Fatality In The Hamster Model Of Clostridioides [Clostridium] Difficile Infection, Amelia E. Fox-King, Chrisabelle Mefferd, Jacqueline R. Phan, Nancy O. Nou, Ernesto Abel-Santos, Brian P. Hedlund Oct 2018

Vancomycin Delays Clindamycin-Induced Fatality In The Hamster Model Of Clostridioides [Clostridium] Difficile Infection, Amelia E. Fox-King, Chrisabelle Mefferd, Jacqueline R. Phan, Nancy O. Nou, Ernesto Abel-Santos, Brian P. Hedlund

LSAMP Poster Presentations

Antibiotics can leave the host gut microbiome susceptible to Clostridioides [Clostridium] difficile colonization and lethal toxin production. For instance, clindamycin-induced susceptibility to C. difficile infection (CDI) results in rapid fatality in hamster models, yet vancomycin has been shown to offer increased survival in hamsters challenged with C. difficile. We aim to develop an antibiotic treatment that will facilitate CDI susceptibility without prompt fatality in hamster models. An antibiotic regimen starting with a continuous vancomycin treatment along with a single clindamycin dosage is thought to reduce the major disruption in the indigenous gut microbiome and prevent clindamycin-induced death. Quantitative polymerase chain ...


Simulating Antibiotic Resistance In The Computer Lab And Biology Lab: Ideas For Undergraduate Projects, Anne E. Yust Oct 2018

Simulating Antibiotic Resistance In The Computer Lab And Biology Lab: Ideas For Undergraduate Projects, Anne E. Yust

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Select Gp120 V2 Domain Specific Antibodies Derived From Hiv And Siv Infection And Vaccination Inhibit Gp120 Binding To Alpha4beta7, Sakaorat Lertjuthaporn, Shan Lu, Yang Lou, Shixia Wang, James Arthos Aug 2018

Select Gp120 V2 Domain Specific Antibodies Derived From Hiv And Siv Infection And Vaccination Inhibit Gp120 Binding To Alpha4beta7, Sakaorat Lertjuthaporn, Shan Lu, Yang Lou, Shixia Wang, James Arthos

Open Access Articles

The GI tract is preferentially targeted during acute/early HIV-1 infection. Consequent damage to the gut plays a central role in HIV pathogenesis. The basis for preferential targeting of gut tissues is not well defined. Recombinant proteins and synthetic peptides derived from HIV and SIV gp120 bind directly to integrin alpha4beta7, a gut-homing receptor. Using both cell-surface expressed alpha4beta7 and a soluble alpha4beta7 heterodimer we demonstrate that its specific affinity for gp120 is similar to its affinity for MAdCAM (its natural ligand). The gp120 V2 domain preferentially engages extended forms of alpha4beta7 in a cation -sensitive manner and is inhibited ...


Lack Of Evidence For Erm(B) Infiltration Into Erythromycin-Resistant Campylobacter Coli And Campylobacter Jejuni From Commercial Turkey Production In Eastern North Carolina: A Major Turkey-Growing Region In The United States, Hannah K. Bolinger, Qijing Zhang, William G. Miller, Sophia Kathariou Aug 2018

Lack Of Evidence For Erm(B) Infiltration Into Erythromycin-Resistant Campylobacter Coli And Campylobacter Jejuni From Commercial Turkey Production In Eastern North Carolina: A Major Turkey-Growing Region In The United States, Hannah K. Bolinger, Qijing Zhang, William G. Miller, Sophia Kathariou

Veterinary Microbiology and Preventive Medicine Publications

In Campylobacter spp., resistance to erythromycin and other macrolides has typically implicated ribosomal mutations, especially substitutions in the 23S rRNA genes. However, in 2014, the macrolide resistance gene erm(B) was reported for the first time in Campylobacter and shown to be harbored by a multidrug resistance island in the chromosome of the swine-derived strain Campylobacter coli ZC113. erm(B)-positive C. coli and Campylobacter jejuni strains from the food supply have been mostly reported from China. However, erm(B)-positive C. coli isolates were also detected recently in fecal samples from turkeys in Spain. To determine whether erm(B ...


High-Throughput Nanoliter Dispensing Device For Biological Applications, Cole Reynolds, Euiwon Bae Dr., J Paul Robinson Dr. Aug 2018

High-Throughput Nanoliter Dispensing Device For Biological Applications, Cole Reynolds, Euiwon Bae Dr., J Paul Robinson Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Pathogen identification is a field that can contribute largely to the prevention of the spreading of illness and disease. In the past, pathogen identification has been a long and arduous process due to the time-consuming processes and steps that requires technician’s time and effort. With new technologies emerging however, screening of bacteria colonies can be done in a quick and high-throughput way. The problem is that using the current methods, bacteria cannot be transferred to petri dishes fast enough to keep up with the new screening methods. The current study focuses on exploring different methods to create an ergonomic ...


Transporters Mrp1 And Mrp2 Regulate Opposing Inflammatory Signals To Control Transepithelial Neutrophil Migration During Streptococcus Pneumoniae Lung Infection, Andrew Zukauskas, Randall J. Mrsny, Paula Cortes Barrantes, Jerrold R. Turner, John M. Leong, Beth A. Mccormick Jul 2018

Transporters Mrp1 And Mrp2 Regulate Opposing Inflammatory Signals To Control Transepithelial Neutrophil Migration During Streptococcus Pneumoniae Lung Infection, Andrew Zukauskas, Randall J. Mrsny, Paula Cortes Barrantes, Jerrold R. Turner, John M. Leong, Beth A. Mccormick

Open Access Articles

Streptococcus pneumoniae remains a source of morbidity and mortality in both developed and underdeveloped nations of the world. Disease can manifest as pneumonia, bacteremia, and meningitis, depending on the localization of infection. Interestingly, there is a correlation in experimental murine infections between the development of bacteremia and influx of neutrophils into the pulmonary lumen. Reduction of this neutrophil influx has been shown to improve survivability during infection. In this study, we use in vitro biotinylation and neutrophil transmigration and in vivo murine infection to identify a system in which two epithelium-localized ATP-binding cassette transporters, MRP1 and MRP2, have inverse activities ...


Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta Jul 2018

Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ixodes scapularis ticks transmit several pathogens to humans including rickettsial bacterium, Anaplasma phagocytophilum. Here, we report that A. phagocytophilum uses tick transcriptional activator protein-1 (AP-1) as a molecular switch in the regulation of arthropod antifreeze gene, iafgp. RNAi-mediated silencing of ap-1 expression significantly affected iafgp gene expression and A. phagocytophilum burden in ticks upon acquisition from the murine host. Gel shift assays provide evidence that both the bacterium and AP-1 influences iafgp promoter and expression. The luciferase assays revealed that a region of approximately 700 bp upstream of the antifreeze gene is sufficient for AP-1 binding to promote iafgp gene ...


Novel Role Of Pseudomonas Aeruginosa Lptd Operon, Sundar Pandey Jun 2018

Novel Role Of Pseudomonas Aeruginosa Lptd Operon, Sundar Pandey

FIU Electronic Theses and Dissertations

Pseudomonas aeruginosais an opportunistic pathogen that infects cystic fibrosis (CF) patients contributing to their high morbidity and mortality. P. aeruginosaundergoes a phenotypic conversion in the CF lung, from nonmucoid to mucoid, by constitutively producing a polysaccharide called alginate. These mucoid strains often revert to nonmucoid in vitrodue to second-site suppressor mutations. We hypothesized that mapping these mutations would lead to the identification of novel genes involved in alginate production. In a previous study, a mucoid strain, PDO300 (PAOmucA22), was used to isolate suppressors of alginate phenotype (sap). One of the uncharacterized nonmucoid revertants, sap27, is the ...


The Role Of Eukaryotic Abc-Transporters In Eliciting Neutrophil Infiltration During Streptococcus Pneumoniae Infection, Andrew Zukauskas Jun 2018

The Role Of Eukaryotic Abc-Transporters In Eliciting Neutrophil Infiltration During Streptococcus Pneumoniae Infection, Andrew Zukauskas

GSBS Dissertations and Theses

Streptococcus pneumoniae (S. pneumoniae) is a Gram-positive, encapsulated bacterium capable of causing significant morbidity and mortality throughout the world. A hallmark of S. pneumoniae infection is infiltration of neutrophils (PMNs) that assist in controlling the spread infection but may also contribute to pathology. Paradoxically, studies have shown that limiting PMN infiltration into the lumen of the lung during infection actually betters clinical outcome in experimental S. pneumoniae infection. The final step in PMN luminal trafficking is a Hepoxilin A3 (HXA3)-dependent migration across the pulmonary epithelium. HXA3 is a PMN chemoattractant that forms gradients along the polarized epithelial ...


Assembly-Hub Function Of Er-Localized Snare Proteins In Biogenesis Of Tombusvirus Replication Compartment, Zsuzsanna Sasvari, Nikolay Kovalev, Paulina Alatriste Gonzalez, Kai Xu, Peter D. Nagy May 2018

Assembly-Hub Function Of Er-Localized Snare Proteins In Biogenesis Of Tombusvirus Replication Compartment, Zsuzsanna Sasvari, Nikolay Kovalev, Paulina Alatriste Gonzalez, Kai Xu, Peter D. Nagy

Plant Pathology Faculty Publications

Positive-strand RNA viruses assemble numerous membrane-bound viral replicase complexes within large replication compartments to support their replication in infected cells. Yet the detailed mechanism of how given subcellular compartments are subverted by viruses is incompletely understood. Although, Tomato bushy stunt virus (TBSV) uses peroxisomal membranes for replication, in this paper, we show evidence that the ER-resident SNARE (soluble NSF attachment protein receptor) proteins play critical roles in the formation of active replicase complexes in yeast model host and in plants. Depletion of the syntaxin 18-like Ufe1 and Use1, which are components of the ER SNARE complex in the ERAS (ER ...


Nutritional Virulence Of Legionella Pneumophila., Ashley M. Best May 2018

Nutritional Virulence Of Legionella Pneumophila., Ashley M. Best

Electronic Theses and Dissertations

Legionella pneumophila is an environment organism that parasitizes a wide range of protozoa. Growth within the environmental host primes L. pneumophila for infection of human alveolar macrophages when contaminated aerosols are inhaled. Intracellular replication within either host requires the establishment a replicative niche, known as the Legionella-containing vacuole (LCV). Biogenesis of the LCV depends on the type IVb translocation system, the Dot/Icm, to translocation >320 effectors into the host cytosol. Effectors are responsible for preventing lysosome fusion to the LCV, recruitment of ER-derived vesicles to the LCV, and modulation of a plethora of host processes to promote the ...


Characterization Of Type Ii Toxin Anti-Toxin Systems In Aggregatibacter Actinomycetemcomitans., Blair W. Schneider May 2018

Characterization Of Type Ii Toxin Anti-Toxin Systems In Aggregatibacter Actinomycetemcomitans., Blair W. Schneider

Electronic Theses and Dissertations

Microbes express many protective mechanisms in response to environmental stress. Toxin/anti-toxin systems encode a biologically active toxin and a labile anti-toxin that inhibits the toxin’s activity. These systems are known to contribute to persister cell and biofilm formation. A. actinomycetemcomitans thrives in the complex oral microbial community and is subjected to continual environmental flux. Little is known regarding the presence and function of TA systems in this organism or their contribution survival in the oral environment. Using BLAST searches and other informatics tools, we identified 11 intact TA systems that are conserved across all seven serotypes of A ...


Characterizing The Virulence Factor Yape In Yersinia Pestis., Tiva Templeton Vancleave May 2018

Characterizing The Virulence Factor Yape In Yersinia Pestis., Tiva Templeton Vancleave

Electronic Theses and Dissertations

Yersinia pestis is the causative agent of bubonic plague and is primarily transmitted by fleas. Upon infection, the bacteria rapidly travel to the regional lymph nodes causing inflammation and cellulitis in these tissues (referred to as buboes). Two outer membrane proteins, YapE and Pla, have been implicated to have roles in dissemination to the lymph nodes. Their adhesive properties have shown that they are able to interact with host macrophages thereby increasing their ability to disseminate to regional lymph nodes. More recently, we have shown that YapE is cleaved by another virulence factor important for lymph node colonization, Pla, to ...


Downregulation Of Microrna Eca-Mir-128 In Seminal Exosomes And Enhanced Expression Of Cxcl16 In The Stallion Reproductive Tract Are Associated With Long-Term Persistence Of Equine Arteritis Virus, Mariano Carossino, Pouya Dini, Theodore S. Kalbfleisch, Alan T. Loynachan, Igor F. Canisso, Kathleen M. Shuck, Peter J. Timoney, R. Frank Cook, Udeni B. R. Balasuriya May 2018

Downregulation Of Microrna Eca-Mir-128 In Seminal Exosomes And Enhanced Expression Of Cxcl16 In The Stallion Reproductive Tract Are Associated With Long-Term Persistence Of Equine Arteritis Virus, Mariano Carossino, Pouya Dini, Theodore S. Kalbfleisch, Alan T. Loynachan, Igor F. Canisso, Kathleen M. Shuck, Peter J. Timoney, R. Frank Cook, Udeni B. R. Balasuriya

Gluck Equine Research Center Faculty Publications

Equine arteritis virus (EAV) can establish long-term persistent infection in the reproductive tract of stallions and is shed in the semen. Previous studies showed that long-term persistence is associated with a specific allele of the CXCL16 gene (CXCL16S) and that persistent infection is maintained despite the presence of a local inflammatory and humoral and mucosal antibody responses. In this study, we demonstrated that equine seminal exosomes (SEs) are enriched in a small subset of microRNAs (miRNAs). Most importantly, we demonstrated that long-term EAV persistence is associated with the downregulation of an SE-associated miRNA (eca-mir-128) and with an enhanced expression of ...


Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis, Malik Raynor May 2018

Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis, Malik Raynor

UT GSBS Dissertations and Theses (Open Access)

Bacillus anthracis produces three regulators, AtxA, AcpA, and AcpB, that control virulence gene expression and are members of an emerging class of regulators termed “PCVRs” (Phosphoenolpyruvate-dependent phosphotransferase regulation Domain-Containing Virulence Regulators). AtxA controls expression of the toxin genes; lef, cya, and pag, and is the master virulence regulator and archetype PCVR. AcpA and AcpB are less well studied. AcpA and AcpB independently positively control transcription of the capsule biosynthetic operon capBCADE, and culture conditions that enhance AtxA activity result in capBCADE transcription in strains lacking acpA and acpB. RNA-Seq was used to assess the regulons of the paralogs in strains ...


The Unusual Paradigm Of The Acid Response Two Component System Of Helicobacter Pylori, Anna Kenan May 2018

The Unusual Paradigm Of The Acid Response Two Component System Of Helicobacter Pylori, Anna Kenan

Undergraduate Honors Theses

Two component signal transduction systems in bacteria are key for environmental adaptation. Signaling via these systems is traditionally considered to be relatively simple, only involving interactions between the sensory protein and its cognate response regulator. The ArsRS two component system is vital for the acid response in Helicobacter pylori. This study investigates the mechanism by which ArsRS responds to acid in H pylori. Recent studies in our lab have challenged the the classic model in which the response regulator ArsR is activated by the phosphorylation of a conserved aspartic acid by the transfer of a phosphoryl group from a histidine ...


Changes In The Prevalence Of Salmonella Serovars Associated Swine Production And Correlations Of Avian, Bovine And Swine‐Associated Serovars With Human‐Associated Serovars In The United States (1997–2015), Chaohui Yuan, Adam C. Krull, Chong Wang, M. Erdman, P. J. Fedorka-Cray, C. M. Logue, Annette M. O'Connor Apr 2018

Changes In The Prevalence Of Salmonella Serovars Associated Swine Production And Correlations Of Avian, Bovine And Swine‐Associated Serovars With Human‐Associated Serovars In The United States (1997–2015), Chaohui Yuan, Adam C. Krull, Chong Wang, M. Erdman, P. J. Fedorka-Cray, C. M. Logue, Annette M. O'Connor

Veterinary Diagnostic and Production Animal Medicine Publications

As Salmonella enterica is an important pathogen of food animals, surveillance programmes for S. enterica serovars have existed for many years in the United States. Surveillance programmes serve many purposes, one of which is to evaluate alterations in the prevalence of serovars that may signal changes in the ecology of the target organism. The primary aim of this study was to evaluate changes in the proportion of S. enterica serovars isolated from swine over a near 20‐year observation period (1997–2015) using four longitudinal data sets from different food animal species. The secondary aim was to evaluate correlations between ...