Functional expression and initial biochemical characterization of Yp-NhaP, cation-proton antiporter from Yersinia pestis
| dc.contributor.author | Abboud, Talal | |
| dc.contributor.examiningcommittee | Court, Deborah (Microbiology) Khajehpour, Mazdak (Chemistry) | en_US |
| dc.contributor.supervisor | Dibrov, Pavel (Microbiology) | en_US |
| dc.date.accessioned | 2011-09-06T14:44:11Z | |
| dc.date.available | 2011-09-06T14:44:11Z | |
| dc.date.issued | 2011-09-06 | |
| dc.degree.discipline | Microbiology | en_US |
| dc.degree.level | Master of Science (M.Sc.) | en_US |
| 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. | en_US |
| dc.description.note | October 2011 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/4841 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Y.pestis | en_US |
| dc.subject | Antiporter | en_US |
| dc.title | Functional expression and initial biochemical characterization of Yp-NhaP, cation-proton antiporter from Yersinia pestis | en_US |
| dc.type | master thesis | en_US |