{"id":{"repo_id":"manitoba","oai_identifier":"oai:mspace.lib.umanitoba.ca:1993/4841"},"canonical_url":"https://search.dev.ndltd.org/etd/manitoba/oai:mspace.lib.umanitoba.ca:1993/4841","repository":{"repo_id":"manitoba","name":"University of Manitoba","base_url":"https://mspace.lib.umanitoba.ca/oai/request"},"display":{"title":"Functional expression and initial biochemical characterization of Yp-NhaP, cation-proton antiporter from Yersinia pestis","abstract":"The major objectives of this work were cloning, functional expression and primary biochemical characterization of Yp-NhaP, putative sodium-proton antiporter from the dangerous human pathogen Yersinia pestis. We expressed Yp-NhaP in its functional form in the antiporter-deficient strain of E. coli, TO114. When assayed in inside-out sub-bacterial membrane vesicles, Yp-NhaP acted as an electroneutral cation/proton antiporter, exchanging Ca2+, K+, Na+ and Li+ ions for H+. Competition experiments suggested that in vivo Yp-NhaP operates as Ca2+/H+ and, possibly, Ca2+/Na+ antiporter rather than K+/H+ or Na+/H+ antiporter. Ca2+/H+ and Li+/H+ antiport catalyzed by Yp-NhaP peaked at pH close to 8.0, while K+/H+ and Na+/H+ antiport were smoothly increasing from pH 6.5 to pH 9.0. We also observed inhibition by the excess of substrate in the case of Ca2+/H+ and Li+/H+ antiport mediated by Yp-NhaP. As expected, chromosomal deletion of Yp-nhaP gene did not affect resistance of Y. pestis cells to alkali cations.","abstract_html":"The major objectives of this work were cloning, functional expression and primary biochemical characterization of Yp-NhaP, putative sodium-proton antiporter from the dangerous human pathogen Yersinia pestis. We expressed Yp-NhaP in its functional form in the antiporter-deficient strain of E. coli, TO114. When assayed in inside-out sub-bacterial membrane vesicles, Yp-NhaP acted as an electroneutral cation/proton antiporter, exchanging Ca2+, K+, Na+ and Li+ ions for H+. Competition experiments suggested that in vivo Yp-NhaP operates as Ca2+/H+ and, possibly, Ca2+/Na+ antiporter rather than K+/H+ or Na+/H+ antiporter. Ca2+/H+ and Li+/H+ antiport catalyzed by Yp-NhaP peaked at pH close to 8.0, while K+/H+ and Na+/H+ antiport were smoothly increasing from pH 6.5 to pH 9.0. We also observed inhibition by the excess of substrate in the case of Ca2+/H+ and Li+/H+ antiport mediated by Yp-NhaP. As expected, chromosomal deletion of Yp-nhaP gene did not affect resistance of Y. pestis cells to alkali cations.","abstract_has_math":false,"creators":["Abboud, Talal"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Dibrov, Pavel (Microbiology)"],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-09-06","date_published":"2011-09-06","updated_at":"2026-07-24T03:02:03Z","subjects":["Y.pestis","Antiporter"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1993/4841","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.supervisor","label":"Supervisor","values":["Dibrov, Pavel (Microbiology)"]},{"key":"dc:creator","label":"Author","values":["Abboud, Talal"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2011-09-06T14:44:11Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2011-09-06T14:44:11Z"]},{"key":"dc:date.issued","label":"Date","values":["2011-09-06"]},{"key":"dc:type","label":"Dc Type","values":["master thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Y.pestis","Antiporter"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1993/4841"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The major objectives of this work were cloning, functional expression and primary biochemical characterization of Yp-NhaP, putative sodium-proton antiporter from the dangerous human pathogen Yersinia pestis. We expressed Yp-NhaP in its functional form in the antiporter-deficient strain of E. coli, TO114. When assayed in inside-out sub-bacterial membrane vesicles, Yp-NhaP acted as an electroneutral cation/proton antiporter, exchanging Ca2+, K+, Na+ and Li+ ions for H+. Competition experiments suggested that in vivo Yp-NhaP operates as Ca2+/H+ and, possibly, Ca2+/Na+ antiporter rather than K+/H+ or Na+/H+ antiporter. Ca2+/H+ and Li+/H+ antiport catalyzed by Yp-NhaP peaked at pH close to 8.0, while K+/H+ and Na+/H+ antiport were smoothly increasing from pH 6.5 to pH 9.0. We also observed inhibition by the excess of substrate in the case of Ca2+/H+ and Li+/H+ antiport mediated by Yp-NhaP. As expected, chromosomal deletion of Yp-nhaP gene did not affect resistance of Y. pestis cells to alkali cations."]},{"key":"dc:title","label":"Title","values":["Functional expression and initial biochemical characterization of Yp-NhaP, cation-proton antiporter from Yersinia pestis"]}]}],"canonical_facts":{"dc:contributor.supervisor":["Dibrov, Pavel (Microbiology)"],"dc:creator":["Abboud, Talal"],"dc:date.accessioned":["2011-09-06T14:44:11Z"],"dc:date.available":["2011-09-06T14:44:11Z"],"dc:date.issued":["2011-09-06"],"dc:description.abstract":["The major objectives of this work were cloning, functional expression and primary biochemical characterization of Yp-NhaP, putative sodium-proton antiporter from the dangerous human pathogen Yersinia pestis. We expressed Yp-NhaP in its functional form in the antiporter-deficient strain of E. coli, TO114. When assayed in inside-out sub-bacterial membrane vesicles, Yp-NhaP acted as an electroneutral cation/proton antiporter, exchanging Ca2+, K+, Na+ and Li+ ions for H+. Competition experiments suggested that in vivo Yp-NhaP operates as Ca2+/H+ and, possibly, Ca2+/Na+ antiporter rather than K+/H+ or Na+/H+ antiporter. Ca2+/H+ and Li+/H+ antiport catalyzed by Yp-NhaP peaked at pH close to 8.0, while K+/H+ and Na+/H+ antiport were smoothly increasing from pH 6.5 to pH 9.0. We also observed inhibition by the excess of substrate in the case of Ca2+/H+ and Li+/H+ antiport mediated by Yp-NhaP. As expected, chromosomal deletion of Yp-nhaP gene did not affect resistance of Y. pestis cells to alkali cations."],"dc:identifier.uri":["http://hdl.handle.net/1993/4841"],"dc:language.iso":["eng"],"dc:subject":["Y.pestis","Antiporter"],"dc:title":["Functional expression and initial biochemical characterization of Yp-NhaP, cation-proton antiporter from Yersinia pestis"],"dc:type":["master thesis"]},"updated_at":"2026-07-24T03:02:03Z"}