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Study Of Rickettsia Parkeri Colonization And Proliferation In The Tick Host Amblyomma Maculatum (Acari: Ixodidae), Khemraj Budachetri 2017 University of Southern Mississippi

Study Of Rickettsia Parkeri Colonization And Proliferation In The Tick Host Amblyomma Maculatum (Acari: Ixodidae), Khemraj Budachetri

Dissertations

Amblyomma maculatum (Gulf coast tick) ticks are prevalent across the Atlantic to Gulf Coast region of United States. These ticks are recognized vectors of Rickettsia parkeri, a spotted fever group of Rickettsia (SFGR) known to cause American boutonneuse fever associated with fever and eschar rashes localized to the site of bites. We hypothesized that Rickettsia parkeri colonization and proliferation in the tick vector involve pathogen-symbiont dynamics and tick-pathogen interactions, which influence rickettsial transmission to the victims after tick bites. The rickettsial infection is maintained across the tick life cycle for many generations due to transovarial and transstadial transmission of …


Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett 2017 East Tennessee State University

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …


Proteomic Identification Of Histone Post-Translational Modifications Induced By Dna Double-Strand Breaks And Novel Proteins Involved In The Dna Damage Response, Pingping Wang 2017 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Proteomic Identification Of Histone Post-Translational Modifications Induced By Dna Double-Strand Breaks And Novel Proteins Involved In The Dna Damage Response, Pingping Wang

Dissertations and Theses (Open Access)

Inaccurate repair of DNA double-strand breaks (DSBs) can lead to DNA mutation and chromosome rearrangements, causing human diseases such as cancer. Although we know the basic mechanisms of DSB repair, the added complexities in the chromatin context are unclear. This is partially due to the lack of unbiased systems for identifying proteins and post-translational modifications (PTMs) involved in DSB repair. In this work, we established a novel method, termed DSB-ChAP-MS (Double Strand Break-Chromatin Affinity Purification with Mass Spectrometry), for the affinity purification of a sequence-specific single copy endogenous chromosomal locus containing a DSB, followed by the proteomic identification of enriched …


Evaluating The Impact Of Post-Translational Modifications By The Secreted Zinc Metalloprotease, Gele, On The Major Autolysin Of E. Faecalis, Atla, And A Stress-Induced Protein, Salb, Emily K. Stinemetz 2017 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Evaluating The Impact Of Post-Translational Modifications By The Secreted Zinc Metalloprotease, Gele, On The Major Autolysin Of E. Faecalis, Atla, And A Stress-Induced Protein, Salb, Emily K. Stinemetz

Dissertations and Theses (Open Access)

AtlA is the major peptidoglycan hydrolase of E. faecalis involved in cell separation of dividing cells. SalB is a secreted stress-induced protein regulated by the CroRS system. In addition, these two proteins also appear to be affected by the virulence factor, gelatinase (GelE). GelE is a secreted zinc metalloprotease known to impact various cellular functions by post- translational modification of protein substrates. The overall objective of this work was to understand how GelE cleavage of secreted proteins, specifically AtlA and SalB, changes their function. Herein, I discovered that GelE modifies both AtlA and SalB. As visualized by Western blot analysis …


Analysis Of The Biochemical And Cellular Activities Of Substrate Binding By The Molecular Chaperone Hsp110/Sse1, Veronica M. Garcia 2017 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Analysis Of The Biochemical And Cellular Activities Of Substrate Binding By The Molecular Chaperone Hsp110/Sse1, Veronica M. Garcia

Dissertations and Theses (Open Access)

Molecular chaperones ensure protein quality during protein synthesis, delivery, damage repair, and degradation. The ubiquitous and highly conserved molecular chaperone 70-kDa heat-shock proteins (Hsp70s) are essential in maintaining protein homeostasis by cycling through high and low affinity binding of unfolded protein clients to facilitate folding. The Hsp110 class of chaperones are divergent relatives of Hsp70 that are extremely effective in preventing protein aggregation but lack the hallmark folding activity seen in Hsp70s. Hsp110s serve as Hsp70 nucleotide exchange factors (NEF) that facilitate the Hsp70 folding cycle by inducing release of protein substrate from Hsp70, thus recycling the chaperone for a …


Characterization Of The Role Of The Pkm101-Encoded T4ss Outer Membrane Core Complex In Substrate Transfer, Pilus Biogenesis, And Recipient Cell Contact, Jay E. Gordon 2017 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Characterization Of The Role Of The Pkm101-Encoded T4ss Outer Membrane Core Complex In Substrate Transfer, Pilus Biogenesis, And Recipient Cell Contact, Jay E. Gordon

Dissertations and Theses (Open Access)

The bacterial type IV secretion systems (T4SS) encoded on the Escherichia coli pKM101 and R388 conjugative plasmids and the Agrobacterium tumefaciens virB operon are composed of 12 subunits arranged in an architecturally similar fashion. Structural studies of the T4SS from R388 (TrwR388) highlighted the presence of a distinct outer membrane core complex (OMCC) and inner membrane complex (IMC) joined together by a central stalk. This thesis is focused on the development of the pKM101 model system and the role of an OMCC cap region formed by alpha helical antenna projections (AP) found in VirB10 and TraFpKM101. …


The Bovine Rumen Microbiome Revealed By Different Fractions Of Rumen Contents, Ashlee L. Breakstone 2017 University of Arkansas, Fayetteville

The Bovine Rumen Microbiome Revealed By Different Fractions Of Rumen Contents, Ashlee L. Breakstone

Animal Science Undergraduate Honors Theses

The bovine rumen microbiota is very important in terms of animal functionality and digestion. The fermentative capability of the rumen provides means for the digestion of complex plant material that is indigestible by humans. The rumen is the working ground for millions of microorganisms, primarily bacteria, to digest and ferment feed into volatile fatty acids and bacterial protein for the animal’s energy and protein needs, respectively. Of significant importance is the rumen microbiomes ability to conform to certain factors such as genetics, feed, or geographic location. These changes can have a direct measure on animal growth, health, and performance. The …


Borrelia Burgdorferi-Specific Iga In Lyme Disease, Christina D'Arco, Raymond Dattwyler, Paul Arnaboldi 2017 New York Medical College

Borrelia Burgdorferi-Specific Iga In Lyme Disease, Christina D'Arco, Raymond Dattwyler, Paul Arnaboldi

NYMC Faculty Publications

The laboratory diagnosis of Lyme disease is currently dependent on the detection of IgM and IgG antibodies against Borrelia burgdorferi, the causative agent of the disease. The significance of serum IgA against B. burgdorferi remains unclear. The production of intrathecal IgA has been noted in patients with the late Lyme disease manifestation, neuroborreliosis, but production of antigen-specific IgA during early disease has not been evaluated. In the current study, we assessed serum IgA binding to the B. burgdorferi peptide antigens, C6, the target of the FDA-cleared C6 EIA, and FlaB(211-223)-modVlsE(275-291), a peptide containing a Borrelia flagellin epitope linked to a …


Evaluation Of A Fluorescence Method For Quantifying Bioaerosol Concentrations On Air Quality Filter Samples, Rachel Kolberg 2017 University of Nevada, Las Vegas

Evaluation Of A Fluorescence Method For Quantifying Bioaerosol Concentrations On Air Quality Filter Samples, Rachel Kolberg

UNLV Theses, Dissertations, Professional Papers, and Capstones

Airborne particulate matter (PM) in outdoor environments contains many components that cause adverse human health effects. The size of the particulates determine in what manner the particles would bypass the body’s defense mechanisms to enter the respiratory system and is directly related to their health impacts. Currently the United States Environmental Protection Agency is enforcing the National Ambient Air Quality Standards (NAAQS) to regulate the annual and 24-hour average concentrations of PM2.5 and PM10 in the air. PM2.5 are fine particles with aerodynamic diameter <2.5μm, small enough to reach the deepest parts of the bronchi and lungs. PM10 include PM2.5 and larger particles with aerodynamic diameter of 2.5-10μm. Both PM2.5 and PM10 contain multiple components from multiple sources. Bioaerosols are an important component of PM, but there is limited knowledge about how bioaerosols contribute to PM2.5 and PM10 concentrations. There is also a lack of research about the incidence and prevalence of disease caused by bioaerosols and about the limits of exposure to bioaerosol particulates. The main barrier to assess bioaerosol concentrations and health-related effects is the absence of quick and inexpensive methodology for quantifying bioaerosols. This study explored the feasibility of using fluorescence microscopy to quickly quantify bioaerosols in PM2.5 and PM10 collected on polycarbonate filters. Bioaerosols were stained with a DNA marker directly on a filter, followed by fixation, microscopic imaging, and automatic counting. The method was first validated using reference samples prepared by depositing different known concentrations of E. coli onto blank polycarbonate filters. The results indicated a linear response over two orders of magnitude (R2 = 0.9) and an accuracy within ±25%. E. coli were also deposited onto selected ambient PM10 and PM2.5 filter samples to determine if pre-loaded particles would interfere with bioaerosol imaging and counting. It was found that despite an increase in uncertainty (variability), the calibration slope remained within ±10% of unity for both PM2.5 and PM10 samples. Bioaerosol concentrations in ambient samples, as quantified by this method, were on average 14% higher for PM10 than for PM2.5 acquired concurrently in a desert environment of Las Vegas, Nevada. The application of this method to other types of compliance filters, such as Teflon filters and tapes of a Beta Attenuation Monitor (BAM) were also explored in this study. By means of a high-yield approach this method is expected to facilitate bioaerosol research, support exposure and health assessments, and help refine NAAQS for PM2.5 and PM10.


Isolation Of A Mycobacterium Virus With The Infectivity Rate Tested At Various Temperatures, Katie Wegenast 2017 Bellarmine University

Isolation Of A Mycobacterium Virus With The Infectivity Rate Tested At Various Temperatures, Katie Wegenast

Undergraduate Theses

Isolation techniques developed by the HHMI and the SEA-PHAGES program were used to obtain a bacteriophage from a mixture of loamy clay soil. The sample was retrieved from a forest edge in central Kentucky. The isolate produced large lytic plaques on a lawn of the bacterium Mycobacterium smegmatis. The bacteriophage was purified, amplified, and analyzed using restriction digest analysis with visualization by gel electrophoresis. Restriction digest analysis suggests the virus belongs to a group known as “A”. Mycobacteriophages are placed into distinct groups based on DNA sequences comparison. The next step in the procedure will be to document with …


The Making Of A Pathogen: Implications Of Phage Domestication In Acinetobacter Baumannii, Allison Welp 2017 Bellarmine University

The Making Of A Pathogen: Implications Of Phage Domestication In Acinetobacter Baumannii, Allison Welp

Undergraduate Theses

Mutations and horizontal gene transfer have allowed for rapid evolution of many species of bacteria, allowing them to become more virulent and resistant to antibiotics. As a result of these changes, Acinetobacter baumannii has become one of the most prominent drug-resistant bacteria in hospitals. This nosocomial pathogen is capable of causing a range of infections—from pneumonia to sepsis—and is extremely difficult to eradicate from hospital settings. Despite its current status, this species has not always been apparent in healthcare. The emergence of this organism has been extremely rapid; once an innocuous environmental organism, A. baumannii is now resistant to all …


Non-Capsular Virulence Factors Of Cryptococcus Neoformans, Kirk Nickish 2017 Liberty University

Non-Capsular Virulence Factors Of Cryptococcus Neoformans, Kirk Nickish

Senior Honors Theses

Cryptococcus neoformans is an emerging pathogen that kills hundreds of thousands every year, especially in underdeveloped areas with little access to modern medical care. New treatments for the disease are needed to shorten treatment and decrease the side effects and costs associated with the drugs currently in use. Many C. neoformans genes have been identified that are necessary for full virulence in the host. Cir1, a regulatory protein associated with iron regulation, and Zip1, a surface zinc transporter, are both necessary for full virulence in the host. Anti-fungals targeted at these proteins or the proteins produced by other genes discussed …


Accumulation And Expression Of Multiple Antibiotic Resistance Genes In Arcobacter Cryaerophilus That Thrives In Sewage, Jess A. Millar, Rahul Raghavan 2017 Portland State University

Accumulation And Expression Of Multiple Antibiotic Resistance Genes In Arcobacter Cryaerophilus That Thrives In Sewage, Jess A. Millar, Rahul Raghavan

Biology Faculty Publications and Presentations

We explored the bacterial diversity of untreated sewage influent samples of a wastewater treatment plant in Tucson, AZ and discovered that Arcobacter cryaerophilus, an emerging human pathogen of animal origin, was the most dominant bacterium. The other highly prevalent bacteria were members of the phyla Bacteroidetes and Firmicutes, which are major constituents of human gut microbiome, indicating that bacteria of human and animal origin intermingle in sewage. By assembling a near-complete genome of A. cryaerophilus, we show that the bacterium has accumulated a large number of antibiotic resistance genes (ARGs) probably enabling it to thrive in the wastewater. We also …


Draft Nuclear Genome Sequence Of The Liquid Hydrocarbon–Accumulating Green Microalga Botryococcus Braunii Race B (Showa), Daniel R. Browne, Jerry Jenkins, Jeremy Schmutz, Shengqiang Shu, Kerrie Barry, Jane Grimwood, Jennifer Chiniquy, Aditi Sharma, Thomas Daniel Niehaus, Taylor L. Weiss, Andrew T. Koppisch, David T. Fox, Suraj Dhungana, Shigeru Okada, Joe Chappell, Timothy P. Devarenne 2017 Texas A&M University

Draft Nuclear Genome Sequence Of The Liquid Hydrocarbon–Accumulating Green Microalga Botryococcus Braunii Race B (Showa), Daniel R. Browne, Jerry Jenkins, Jeremy Schmutz, Shengqiang Shu, Kerrie Barry, Jane Grimwood, Jennifer Chiniquy, Aditi Sharma, Thomas Daniel Niehaus, Taylor L. Weiss, Andrew T. Koppisch, David T. Fox, Suraj Dhungana, Shigeru Okada, Joe Chappell, Timothy P. Devarenne

Plant and Soil Sciences Faculty Publications

Botryococcus braunii has long been known as a prodigious producer of liquid hydrocarbon oils that can be converted into combustion engine fuels. This draft genome for the B race of B. braunii will allow researchers to unravel important hydrocarbon biosynthetic pathways and identify possible regulatory networks controlling this unusual metabolism.


Antimicrobial Properties Of S-Benzofuran-2-Yl Ethanol Produced By Biotransformation, Nick Cheatwood, Ann Davis, Elizabeth Schabeck, Kelsi Hooker, Michele Harris 2017 Stephen F Austin State University

Antimicrobial Properties Of S-Benzofuran-2-Yl Ethanol Produced By Biotransformation, Nick Cheatwood, Ann Davis, Elizabeth Schabeck, Kelsi Hooker, Michele Harris

Undergraduate Research Conference

All living organisms contain enzymes to carry out biological reactions, which produce substances with a specific three dimensional shape. Enantiomers are two molecules that are mirror images of each other just as hands are mirror images of each other. It is well known in the pharmaceutical world that one of the enantiomers (one of the mirrorimage molecules) has a positive biological effect while the other can be harmful or have no effect. Currently, any potential pharmaceutical that could exist as enantiomers must have each enantiomer tested for biological activity prior to FDA approval. In our laboratory, we have focused on …


Impact Of Cations On The Sorption Capabilities Of Kaolin Towards Biofilm-Forming Bacteria, Rachel E. Brineman 2017 Georgia College and State University

Impact Of Cations On The Sorption Capabilities Of Kaolin Towards Biofilm-Forming Bacteria, Rachel E. Brineman

Georgia College Student Research Events

Biofilm-forming bacteria cause problems for industries such as medical, food, and water treatment. Due to its heterogeneous charges, kaolin is capable of sorption of these microorganisms. These charges are impacted by pH and cations, which change the electrostatic interactions between kaolin particles and microorganisms. Proper pH and cation composition may lead to enhanced sorption. The impact of Al3+ cations on kaolin sorption of Gram negative (E. coli and P. aeruginosa) and Gram positive (B. megaterium and S. aureus) was investigated. Calcined kaolin and Diatomaceous Earth kaolin, which were selected in previous studies, were incubated in triplicates with the above organisms …


Lysine Residues Of Interferon Regulatory Factor 7 Affect The Replication And Transcription Activatormediated Lytic Replication Of Kaposi’S Sarcomaassociated Herpesvirus/Human Herpesvirus 8, Tianzheng Zhang, Ying Wang, Li Zhang, Bin Liu, Jinhui Xie, Charles Wood, Jinzhong Wang 2017 Nankai University

Lysine Residues Of Interferon Regulatory Factor 7 Affect The Replication And Transcription Activatormediated Lytic Replication Of Kaposi’S Sarcomaassociated Herpesvirus/Human Herpesvirus 8, Tianzheng Zhang, Ying Wang, Li Zhang, Bin Liu, Jinhui Xie, Charles Wood, Jinzhong Wang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) infection goes through latent and lytic phases, which are controlled by the viral replication and transcription activator (RTA). Upon KSHV infection, the host responds by suppressing RTA-activated lytic gene expression through interferon regulatory factor 7 (IRF-7), a key regulator of host innate immune response. Lysine residues are potential sites for post-translational modification of IRF-7, and were suggested to be critical for its activity. In this study, we analysed the 15 lysine residues for their effects on IRF-7 function by site-directed mutagenesis. We found that some mutations affect the ability of IRF-7 to activate interferon (IFN)-a1 and …


Respons Tanaman Jagung (Zea Mays L.) Akibat Pemberian Pupuk Fosfat Dan Waktu Aplikasi Pupuk Hayati Mikroba Pelarut Fosfat Pada Ultisols Jatinangor, Agus Wahyudin, Betty Natalie Fitriatin, Fiky Yulianto Wicaksono, Ruminta, A. Rahadiyan 2017 Program Studi Agroteknologi, Fak. Pertanian, Universitas Padjadjaran

Respons Tanaman Jagung (Zea Mays L.) Akibat Pemberian Pupuk Fosfat Dan Waktu Aplikasi Pupuk Hayati Mikroba Pelarut Fosfat Pada Ultisols Jatinangor, Agus Wahyudin, Betty Natalie Fitriatin, Fiky Yulianto Wicaksono, Ruminta, A. Rahadiyan

Jurnal Kultivasi

Jagung merupakan salah satu komoditas tanaman pangan yang mempunyai peranan strategis dalam pembangunan pertanian dan perekonomian Indonesia karena memiliki potensi dalam kebutuhan pangan, pakan, bahan baku industri, dan kerajinan tangan. Penelitian ini bertujuan untuk mengetahui pengaruh jenis pupuk fosfat dan waktu pengaplikasian pupuk hayati mikroba pelarut fosfat (MPF) terhadap pertumbuhan dan hasil tanaman jagung pada Ultisols Jatinangor. Percobaan dilaksanakan di Kebun Percobaan Ciparanje Fakultas Pertanian Universitas Padjadjaran, Jatinangor, Kabupaten Sumedang, Jawa Barat dengan ketinggian tempat +_ 750 meter di atas permukaan laut dan ordo tanah Ultisol, curah hujan rata-rata termasuk tipe C3 menurut Oldeman, dan temperatur udara berkisar antara 22,00 …


Does High Relatedness Promote Cheater-Free Multicellularity In Synthetic Lifecycles?, R F. Inglis, E Ryu, O Asikhia, Joan E. Strassmann, David C. Queller 2017 Washington University in St Louis

Does High Relatedness Promote Cheater-Free Multicellularity In Synthetic Lifecycles?, R F. Inglis, E Ryu, O Asikhia, Joan E. Strassmann, David C. Queller

Biology Faculty Research

The evolution of multicellularity is one of the key transitions in evolution and requires extreme levels of cooperation between cells. However, even when cells are genetically identical, noncooperative cheating mutants can arise that cause a breakdown in cooperation. How then, do multicellular organisms maintain cooperation between cells? A number of mechanisms that increase relatedness amongst cooperative cells have been implicated in the maintenance of cooperative multicellularity including single-cell bottlenecks and kin recognition. In this study, we explore how relatively simple biological processes such as growth and dispersal can act to increase relatedness and promote multicellular cooperation. Using experimental populations of …


Non-Classical Regulators In Staphylococcus Aureus, Andy Weiss 2017 University of South Florida

Non-Classical Regulators In Staphylococcus Aureus, Andy Weiss

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus is a highly problematic human pathogen due to its ability to cause devastating infections, paired with a capacity to withstand the action of a large fraction of available antibiotics. Both pathogenicity and antibiotic resistance are encoded by numerous genomic elements, though the expression of these factors is energetically costly and not always beneficial for cellular survival. Therefore, S. aureus has developed sophisticated regulatory networks to integrate a multitude of signals, enabling it to navigate the delicate balance between its pathogenic lifestyle and baseline needs for cellular energy homeostasis. It is thus imperative to study S. aureus behavior and …


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