{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T14:37:53Z","timestamp":1790260673161,"version":"4.1.0"},"reference-count":35,"publisher":"National Academy of Sciences","issue":"46","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2010,11,16]]},"abstract":"<jats:p>\n                    Gram negative pathogens are protected against toxic electrophilic compounds by glutathione-gated potassium efflux systems (Kef) that modulate cytoplasmic pH. We have elucidated the mechanism of gating through structural and functional analysis of\n                    <jats:italic>Escherichia coli<\/jats:italic>\n                    KefC. The revealed mechanism can explain how subtle chemical differences in glutathione derivatives can produce opposite effects on channel function. Kef channels are regulated by potassium transport and NAD-binding (KTN) domains that sense both reduced glutathione, which inhibits Kef activity, and glutathione adducts that form during electrophile detoxification and activate Kef. We find that reduced glutathione stabilizes an interdomain association between two KTN folds, whereas large adducts sterically disrupt this interaction. F441 is identified as the pivotal residue discriminating between reduced glutathione and its conjugates. We demonstrate a major structural change on the binding of an activating ligand to a KTN-domain protein. Analysis of the regulatory interactions suggests strategies to disrupt pathogen potassium and pH homeostasis.\n                  <\/jats:p>","DOI":"10.1073\/pnas.1012716107","type":"journal-article","created":{"date-parts":[[2010,11,2]],"date-time":"2010-11-02T01:22:00Z","timestamp":1288660920000},"page":"19784-19789","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":76,"title":["Mechanism of ligand-gated potassium efflux in bacterial pathogens"],"prefix":"10.1073","volume":"107","author":[{"given":"Tarmo P.","family":"Roosild","sequence":"first","affiliation":[{"name":"Drug Development Department, Nevada Cancer Institute, Las Vegas, NV 89135;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samantha","family":"Castronovo","sequence":"additional","affiliation":[{"name":"Drug Development Department, Nevada Cancer Institute, Las Vegas, NV 89135;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jess","family":"Healy","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"},{"name":"School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, Scotland, United Kingdom; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samantha","family":"Miller","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christos","family":"Pliotas","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim","family":"Rasmussen","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wendy","family":"Bartlett","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stuart J.","family":"Conway","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ian R.","family":"Booth","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2010,11]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1128\/mr.49.4.359-378.1985","article-title":"Regulation of cytoplasmic pH in bacteria","volume":"49","author":"Booth IR","year":"1985","unstructured":"IR Booth, Regulation of cytoplasmic pH in bacteria. 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J Biol Chem 281, 38573\u201338581 (2006).","journal-title":"J Biol Chem"},{"key":"e_1_3_4_28_2","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1085\/jgp.200609486","article-title":"Intra- and intersubunit cooperativity in activation of BK channels by Ca2+","volume":"128","author":"Qian X","year":"2006","unstructured":"X Qian, X Niu, KL Magleby, Intra- and intersubunit cooperativity in activation of BK channels by Ca2+. J Gen Physiol 128, 389\u2013404 (2006).","journal-title":"J Gen Physiol"},{"key":"e_1_3_4_29_2","doi-asserted-by":"crossref","first-page":"1393","DOI":"10.1128\/AEM.66.4.1393-1399.2000","article-title":"Glutathione-dependent conversion of N-ethylmaleimide to the maleamic acid by Escherichia coli: An intracellular detoxification process","volume":"66","author":"McLaggan D","year":"2000","unstructured":"D McLaggan, H Rufino, M Jaspars, IR Booth, Glutathione-dependent conversion of N-ethylmaleimide to the maleamic acid by Escherichia coli: An intracellular detoxification process. Appl Environ Microbiol 66, 1393\u20131399 (2000).","journal-title":"Appl Environ Microbiol"},{"key":"e_1_3_4_30_2","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/S0076-6879(97)76066-X","article-title":"Processing of X-ray diffraction data collected in oscillation mode","volume":"276","author":"Otwinowski Z","year":"1997","unstructured":"Z Otwinowski, W Minor, Processing of X-ray diffraction data collected in oscillation mode. Methods Enzymol 276, 307\u2013326 (1997).","journal-title":"Methods Enzymol"},{"key":"e_1_3_4_31_2","doi-asserted-by":"crossref","first-page":"760","DOI":"10.1107\/S0907444994003112","article-title":"The CCP4 suite: Programs for protein crystallography","volume":"50","year":"1994","unstructured":", The CCP4 suite: Programs for protein crystallography. Acta Crytallogr D 50, 760\u2013763 (1994).","journal-title":"Acta Crytallogr D"},{"key":"e_1_3_4_32_2","doi-asserted-by":"crossref","first-page":"2126","DOI":"10.1107\/S0907444904019158","article-title":"Coot: Model-building tools for molecular graphics","volume":"60","author":"Emsley P","year":"2004","unstructured":"P Emsley, K Cowtan, Coot: Model-building tools for molecular graphics. Acta Crystallogr D 60, 2126\u20132132 (2004).","journal-title":"Acta Crystallogr D"},{"key":"e_1_3_4_33_2","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1006\/jmbi.1993.1351","article-title":"Main-chain bond lengths and bond angles in protein structures","volume":"231","author":"Laskowski RA","year":"1993","unstructured":"RA Laskowski, DS Moss, JM Thornton, Main-chain bond lengths and bond angles in protein structures. 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