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Showing 1 to 17 of 17 for “"type IV secretion"”.
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Characterization of The Agrobacterium Tumefaciens Virb2 Pilin of The Virb/D4 Type Iv Secretion System
… <em>tumefaciens</em> VirB/D4 type IV secretion system (T4SS) delivers oncogenic T-DNA and effector proteins to susceptible plant cells. This leads to the formation of tumors termed Crown Galls. The VirB/D4 T4SS is comprised of 12 subunits (VirB1 to VirB11 and VirD4), which …
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Development of Chimeric Type Iv Secretion Systems For Transfer of Heterologous Substrates Across The Gram-Negative Cell Envelope
<p>Many bacteria use Type IV Secretion Systems (T4SSs) to aid in pathogenesis by translocating virulence factors across the cell envelope and into eukaryotic cells. These systems are structurally and functionally diverse, but are often compared to the archetypal VirB/VirD4 T4SS of <em>Agrobacterium …
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Molecular Genetic Characterization of the Mating Pair Formation and Vegetative Replication Regions on the Agrobacterium Tumefaciens Ti Plasmid pTiC58
… region, now called trb, and the adjacent vegetative replication (rep) region have been the focus of this dissertation research. Nucleotide sequence analysis of the 11-kb trb region identified 13 significant open reading frames (ORFs). The first, encoding traI, is responsible for the synthesis of …
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Interactions between an integrative and conjugative element and its bacterial host
Conjugative elements are mobile genetic elements that can transfer from a donor bacterium to a recipient via an element-encoded type IV secretion system. Integrative and conjugative elements (ICEs) are an abundant class of conjugative element. ICEs are typically integrated into the bacterial host …
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Characterization of an exclusion mechanism in an integrative and conjugative element in Bacillus subtilis
… new genetic material that can confer novel phenotypes to bacteria and contribute to their evolution. Conjugation is an important mechanism of horizontal gene transfer that involves the direct transfer of DNA between two cells and is mediated by mobile genetic elements encoding type IV secretion …
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A genetic screen to identify novel Helicobacter pylori virulence factors using Saccharomyces cerevisiae as a model eukaryotic cell
<p>"Helicobacter pylori is a spiral, gram-negative bacterium that colonizes the stomachs of approximately 50% of the World's population overall and is a major etiological agent of human gastric adenocarcinoma. Of infected individuals, only 10-15% develop severe gastric disease due to environmental …
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<em>Agrobacterium</em> Virb10 Contributions to Type Iv Substrate Secretion, T-Pilus Biogenesis, and Outer Membrane Pore Formation
The VirB/D4 type IV secretion system (T4SS) of <em>Agrobacterium tumefaciens</em> functions to transfer substrates to infected plant cells through assembly of a translocation channel and a surface structure termed a T-pilus. This thesis is focused on identifying contributions of VirB10 to substrate …
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Characterization of The Role of The Pkm101-Encoded T4Ss Outer Membrane Core Complex In Substrate Transfer, Pilus Biogenesis, and Recipient Cell Contact
<p>The bacterial type IV secretion systems (T4SS) encoded on the <em>Escherichia coli</em> pKM101 and R388 conjugative plasmids and the <em>Agrobacterium tumefaciens</em> <em>virB</em> operon are composed of 12 subunits arranged in an architecturally similar fashion. Structural studies of the T4SS …
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Multiple virulence genes and other MRNA regulatory targets are differentially expressed in two Helicobacter pylori strains overexpressing small RNAs
… and cancer through the action of the cagPAI Type IV secretion system and its associated cytotoxin, CagA. Although the genetic regulation necessary for these and other virulence traits is complicated by a relative lack of regulatory proteins in H. pylori, its wealth of small RNAs (sRNAs) may …
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Characterization of Helicobacter pylori sRNAs HPnc2525, HPnc2600, and HPnc2645
… pylori is a common microaerophilic gram-negative bacterium that infects approximately 50% of the human population. Although all H. pylori infections result in inflammation of the gastric epithelium, only 10-15% of infections are symptomatic and progress to severe gastric diseases such as …
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Mechanisms of Iron Acquisition Employed by Neisseria Gonorrhoeae for Survival within Cervical Epithelial Cells
… of the Ton system and TdTs in gonococcal survival within human cervicalepithelial cells was also determined for two gonococcal strains, FA1090 and MS 1 1. Wedemonstrate that intracellular survival of both strains was dependent upon host cell ironacquisition, yet the expression of the Ton …
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Evasion Of Innate Immunity By The Pathogen Coxiella Burnetii
… causes the emerging disease Q fever. It uses a type IV secretion system (T4SS) to inject over 100 bacterial effector proteins into the host cytoplasm, which modulate many host cellular processes to form a replicative niche for the bacteria inside the cell. We describe here the discovery of a …
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Assessing Helicobacter pylori's HcpE and DsbK's Effects on Immunostimulation in Host Gastric Cells
… patient noncompliance, the search for an alternative treatment is essential. HcpE, a member of the Helicobacter cysteine-rich proteins (Hcps) family, contains the largest number of cysteine residues and is secreted extracellularly. Its structure is made of Sel-Like Repeats (SLR) motifs–stabilized …
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Structural Studies of the Receiver Domain of LytR from Staphylococcus Aureus and Interaction Studies of TraW and TrbC from the F Plasmid of Escherichia Coli
… two-component regulatory system (TCS) and the type IV secretion system (T4SS). Microbes use TCSs to regulate important functions such as sporulation, chemotaxis, as well as autolysis that leads to biofilm formation. In addition, microbes utilize T4SSs to deliver DNA, protein substrates, toxin, …
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Interplay between an integrative and conjugative element and its bacterial host
… Mobile genetic elements (MGEs) are the primary drivers of horizontal gene transfer, introducing large fragments of DNA. Often, MGEs contain cargo genes beneficial to the host, conferring new traits such as antibiotic resistances, pathogenicity, and metabolic capabilities. Though MGEs sometimes …
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Immunogenität translozierter Effektorproteine bei Infektionen mit Bartonella henselae
Bartonella henselae, ein gramnegatives Stäbchenbakterium, ist weltweit verbreitet und bekannt als der Erreger der Katzenkratzkrankheit, einer häufigen Differentialdiagnose einer Lymphadenopathie. Vor allem bei Immunsuppimierten kann Bartonella henselae auch die Bazilläre Angiomatose, die Peliosis …
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An exploratory study of Helicobacter suis control strategies
Helicobacter suis is a Gram-negative, spiral-shaped bacterium that colonizes the stomach of the majority of slaughter pigs worldwide. An infection with this microorganism has been associated with erosive and ulcerative lesions in the non-glandular part of the porcine stomach and with chronic …