\"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 factors, host genetic factors, and more significantly, genetic differences in the infecting H pylori strains. Type I strains of H pylori contain a 40-kb cytotoxin-associated pathogenicity island (cag PAl) that encodes and secretes the CagA protein into host epithelial cells via a type IV secretion system. To date, CagA is the only identified effector protein of the cag PAI. The goal of this study was to identify novel H pylori virulence factors, to further elucidate their role in H pylori virulence and their potential as novel effectors of the cag PAI. In the work presented here, we generated an H pylori genomic plasmid library and screened this library in Saccharomyces cerevisiae for toxic effects. We initially identified 2 candidate H pylori virulence factors, however, after further analysis these candidates were not toxic to S. cerevisiae and are no longer genes of interest. To identify novel H pylori virulence factors, others in the lab are addressing pitfalls found in this study to conduct a better-structured screen that we believe will be successful in identifying H pylori genes of interest\"--Document.
","abstract_html":"<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 factors, host genetic factors, and more significantly, genetic differences in the infecting H pylori strains. Type I strains of H pylori contain a 40-kb cytotoxin-associated pathogenicity island (cag PAl) that encodes and secretes the CagA protein into host epithelial cells via a type IV secretion system. To date, CagA is the only identified effector protein of the cag PAI. The goal of this study was to identify novel H pylori virulence factors, to further elucidate their role in H pylori virulence and their potential as novel effectors of the cag PAI. In the work presented here, we generated an H pylori genomic plasmid library and screened this library in Saccharomyces cerevisiae for toxic effects. We initially identified 2 candidate H pylori virulence factors, however, after further analysis these candidates were not toxic to S. cerevisiae and are no longer genes of interest. To identify novel H pylori virulence factors, others in the lab are addressing pitfalls found in this study to conduct a better-structured screen that we believe will be successful in identifying H pylori genes of interest"--Document.</p>","abstract_has_math":false,"creators":["Bothwell, Amelia M."],"institution":null,"degree_name":"Master of Science (MS) in Biology","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Andrea Castillo","Prakash Bhuta","Nicholas Burgis"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-01-01T08:00:00Z","date_published":"2013-01-01T08:00:00Z","updated_at":"2026-07-24T02:12:52Z","subjects":["Helicobacter pylori","Virulence (Microbiology)--Genetic aspects","Helicobacter pylori infections","Stomach--Diseases","Saccharomyces cerevisiae--Biotechnology","Biology"],"languages":[],"rights":["Access is available to all users"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.ewu.edu/theses/96","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Andrea Castillo","Prakash Bhuta","Nicholas Burgis"]},{"key":"dc:creator","label":"Author","values":["Bothwell, Amelia M."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS) in Biology"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Helicobacter pylori","Virulence (Microbiology)--Genetic aspects","Helicobacter pylori infections","Stomach--Diseases","Saccharomyces cerevisiae--Biotechnology","Biology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Access is available to all users"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.ewu.edu/theses/96"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["\"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 factors, host genetic factors, and more significantly, genetic differences in the infecting H pylori strains. Type I strains of H pylori contain a 40-kb cytotoxin-associated pathogenicity island (cag PAl) that encodes and secretes the CagA protein into host epithelial cells via a type IV secretion system. To date, CagA is the only identified effector protein of the cag PAI. The goal of this study was to identify novel H pylori virulence factors, to further elucidate their role in H pylori virulence and their potential as novel effectors of the cag PAI. In the work presented here, we generated an H pylori genomic plasmid library and screened this library in Saccharomyces cerevisiae for toxic effects. We initially identified 2 candidate H pylori virulence factors, however, after further analysis these candidates were not toxic to S. cerevisiae and are no longer genes of interest. To identify novel H pylori virulence factors, others in the lab are addressing pitfalls found in this study to conduct a better-structured screen that we believe will be successful in identifying H pylori genes of interest\"--Document.
"]},{"key":"dc:title","label":"Title","values":["A genetic screen to identify novel Helicobacter pylori virulence factors using Saccharomyces cerevisiae as a model eukaryotic cell"]}]}],"canonical_facts":{"dc:contributor":["Andrea Castillo","Prakash Bhuta","Nicholas Burgis"],"dc:creator":["Bothwell, Amelia M."],"dc:description.abstract":["\"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 factors, host genetic factors, and more significantly, genetic differences in the infecting H pylori strains. Type I strains of H pylori contain a 40-kb cytotoxin-associated pathogenicity island (cag PAl) that encodes and secretes the CagA protein into host epithelial cells via a type IV secretion system. To date, CagA is the only identified effector protein of the cag PAI. The goal of this study was to identify novel H pylori virulence factors, to further elucidate their role in H pylori virulence and their potential as novel effectors of the cag PAI. In the work presented here, we generated an H pylori genomic plasmid library and screened this library in Saccharomyces cerevisiae for toxic effects. We initially identified 2 candidate H pylori virulence factors, however, after further analysis these candidates were not toxic to S. cerevisiae and are no longer genes of interest. To identify novel H pylori virulence factors, others in the lab are addressing pitfalls found in this study to conduct a better-structured screen that we believe will be successful in identifying H pylori genes of interest\"--Document.
"],"dc:identifier":["https://dc.ewu.edu/theses/96"],"dc:rights":["Access is available to all users"],"dc:subject":["Helicobacter pylori","Virulence (Microbiology)--Genetic aspects","Helicobacter pylori infections","Stomach--Diseases","Saccharomyces cerevisiae--Biotechnology","Biology"],"dc:title":["A genetic screen to identify novel Helicobacter pylori virulence factors using Saccharomyces cerevisiae as a model eukaryotic cell"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science (MS) in Biology"]},"updated_at":"2026-07-24T02:12:52Z"}