{"id":{"repo_id":"uwo","oai_identifier":"oai:uwo.scholaris.ca:20.500.14721/32085"},"canonical_url":"https://search.dev.ndltd.org/etd/uwo/oai:uwo.scholaris.ca:20.500.14721/32085","repository":{"repo_id":"uwo","name":"Western University","base_url":"https://uwo.scholaris.ca/server/oai/request"},"display":{"title":"Screening for purine transporters in S. aureus","abstract":"Staphylococcus aureus is an important human pathogen and crucial part of its pathogenesis depends on its ability to acquire purines to cause disease. In this study, I screened a library of individual mutants under purine import-dependent conditions by inhibiting the purine biosynthesis using the pharmacological agents methotrexate and 6-mercaptopurine and supplementing inosine monophosphate and/or guanine as an exogenous purine source. I identified an ATP-Binding Cassette transporter mutant that failed to grow under the selective purine transport conditions. Further growth characterization of the mutant revealed that the growth defect was not due to an inability to transport purines but rather to downstream effects related to the toxicity of the purine biosynthesis inhibitors. A thorough understanding of S. aureus purine acquisition will allow for development of antimicrobials with prolonged effectiveness.","abstract_html":"Staphylococcus aureus is an important human pathogen and crucial part of its pathogenesis depends on its ability to acquire purines to cause disease. In this study, I screened a library of individual mutants under purine import-dependent conditions by inhibiting the purine biosynthesis using the pharmacological agents methotrexate and 6-mercaptopurine and supplementing inosine monophosphate and/or guanine as an exogenous purine source. I identified an ATP-Binding Cassette transporter mutant that failed to grow under the selective purine transport conditions. Further growth characterization of the mutant revealed that the growth defect was not due to an inability to transport purines but rather to downstream effects related to the toxicity of the purine biosynthesis inhibitors. A thorough understanding of S. aureus purine acquisition will allow for development of antimicrobials with prolonged effectiveness.","abstract_has_math":false,"creators":["Sonpaveerawong, Tothong"],"institution":"The University of Western Ontario","degree_name":"M Sc","degree_level":null,"degree_discipline":"Microbiology and Immunology","degree_department":null,"school":null,"contributors":[],"advisors":["David Heinrichs"],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-05-25","date_published":"2022-05-25","updated_at":"2026-07-27T21:55:59Z","subjects":["Staphylococcus aureus","purine transporter","mntC","Mn homeostasis","superoxide dismutase","methotrexate","6-mercaptopurine"],"languages":["en_ca"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.14721/32085","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["David Heinrichs"]},{"key":"dc:creator","label":"Author","values":["Sonpaveerawong, Tothong"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-07-10T19:26:29Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-07-10T19:26:29Z"]},{"key":"dc:date.issued","label":"Date","values":["2022-05-25"]},{"key":"dc:publisher","label":"Institution","values":["The University of Western Ontario"]},{"key":"dc:type","label":"Dc Type","values":["thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Microbiology and Immunology"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M Sc"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Staphylococcus aureus","purine transporter","mntC","Mn homeostasis","superoxide dismutase","methotrexate","6-mercaptopurine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_ca"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/20.500.14721/32085"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The thesis cover page in the PDF document includes references to Western University’s previous institutional repository platform, known as Scholarship@Western, and links to that platform (beginning with ir.lib.uwo.ca). In citing or referring to this thesis, use the DOI or handle from this page instead. Sample citation: Author name, \"Thesis title.\" (Year). Western University Open Repository. https://doi.org/10.71858/123456."]},{"key":"dc:description.abstract","label":"Abstract","values":["Staphylococcus aureus is an important human pathogen and crucial part of its pathogenesis depends on its ability to acquire purines to cause disease. In this study, I screened a library of individual mutants under purine import-dependent conditions by inhibiting the purine biosynthesis using the pharmacological agents methotrexate and 6-mercaptopurine and supplementing inosine monophosphate and/or guanine as an exogenous purine source. I identified an ATP-Binding Cassette transporter mutant that failed to grow under the selective purine transport conditions. Further growth characterization of the mutant revealed that the growth defect was not due to an inability to transport purines but rather to downstream effects related to the toxicity of the purine biosynthesis inhibitors. A thorough understanding of S. aureus purine acquisition will allow for development of antimicrobials with prolonged effectiveness."]},{"key":"dc:title","label":"Title","values":["Screening for purine transporters in S. aureus"]}]}],"canonical_facts":{"dc:contributor.advisor":["David Heinrichs"],"dc:creator":["Sonpaveerawong, Tothong"],"dc:date.accessioned":["2025-07-10T19:26:29Z"],"dc:date.available":["2025-07-10T19:26:29Z"],"dc:date.issued":["2022-05-25"],"dc:description":["The thesis cover page in the PDF document includes references to Western University’s previous institutional repository platform, known as Scholarship@Western, and links to that platform (beginning with ir.lib.uwo.ca). In citing or referring to this thesis, use the DOI or handle from this page instead. Sample citation: Author name, \"Thesis title.\" (Year). Western University Open Repository. https://doi.org/10.71858/123456."],"dc:description.abstract":["Staphylococcus aureus is an important human pathogen and crucial part of its pathogenesis depends on its ability to acquire purines to cause disease. In this study, I screened a library of individual mutants under purine import-dependent conditions by inhibiting the purine biosynthesis using the pharmacological agents methotrexate and 6-mercaptopurine and supplementing inosine monophosphate and/or guanine as an exogenous purine source. I identified an ATP-Binding Cassette transporter mutant that failed to grow under the selective purine transport conditions. Further growth characterization of the mutant revealed that the growth defect was not due to an inability to transport purines but rather to downstream effects related to the toxicity of the purine biosynthesis inhibitors. A thorough understanding of S. aureus purine acquisition will allow for development of antimicrobials with prolonged effectiveness."],"dc:identifier.uri":["https://hdl.handle.net/20.500.14721/32085"],"dc:language.iso":["en_ca"],"dc:publisher":["The University of Western Ontario"],"dc:subject":["Staphylococcus aureus","purine transporter","mntC","Mn homeostasis","superoxide dismutase","methotrexate","6-mercaptopurine"],"dc:title":["Screening for purine transporters in S. aureus"],"dc:type":["thesis"],"thesis:degree_discipline":["Microbiology and Immunology"],"thesis:degree_name":["M Sc"]},"updated_at":"2026-07-27T21:55:59Z"}