Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex

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Standard

Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex. / Laursen, Mette; Gregersen, Jonas Lindholt; Yatime, Laure; Nissen, Poul; Fedosova, Natalya.

In: PNAS (Proceedings of the National Academy of Sciences of the United States of America), Vol. 112, No. 6, 10.02.2015, p. 1755-1760.

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

Harvard

Laursen, M, Gregersen, JL, Yatime, L, Nissen, P & Fedosova, N 2015, 'Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex', PNAS (Proceedings of the National Academy of Sciences of the United States of America), vol. 112, no. 6, pp. 1755-1760. https://doi.org/10.1073/pnas.1422997112

APA

Laursen, M., Gregersen, J. L., Yatime, L., Nissen, P., & Fedosova, N. (2015). Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex. PNAS (Proceedings of the National Academy of Sciences of the United States of America), 112(6), 1755-1760. https://doi.org/10.1073/pnas.1422997112

CBE

Laursen M, Gregersen JL, Yatime L, Nissen P, Fedosova N. 2015. Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex. PNAS (Proceedings of the National Academy of Sciences of the United States of America). 112(6):1755-1760. https://doi.org/10.1073/pnas.1422997112

MLA

Laursen, Mette et al. "Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex". PNAS (Proceedings of the National Academy of Sciences of the United States of America). 2015, 112(6). 1755-1760. https://doi.org/10.1073/pnas.1422997112

Vancouver

Laursen M, Gregersen JL, Yatime L, Nissen P, Fedosova N. Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex. PNAS (Proceedings of the National Academy of Sciences of the United States of America). 2015 Feb 10;112(6):1755-1760. https://doi.org/10.1073/pnas.1422997112

Author

Laursen, Mette ; Gregersen, Jonas Lindholt ; Yatime, Laure ; Nissen, Poul ; Fedosova, Natalya. / Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex. In: PNAS (Proceedings of the National Academy of Sciences of the United States of America). 2015 ; Vol. 112, No. 6. pp. 1755-1760.

Bibtex

@article{f9656fa4e9704fa8b4541181baccbd2d,
title = "Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex",
abstract = "Cardiotonic steroids (CTSs) are specific and potent inhibitors of the Na+,K+-ATPase, with highest affinity to the phosphoenzyme (E2P) forms. CTSs are comprised of a steroid core, which can be glycosylated, and a varying number of substituents, including a five- or six-membered lactone. These functionalities have specific influence on the binding properties. We report crystal structures of the Na+,K+-ATPase in the E2P form in complex with bufalin (a nonglycosylated CTS with a six-membered lactone) and digoxin (a trisaccharide-conjugated CTS with a five-membered lactone) and compare their characteristics and binding kinetics with the previously described E2P–ouabain complex to derive specific details and the general mechanism of CTS binding and inhibition. CTSs block the extracellular cation exchange pathway, and cation-binding sites I and II are differently occupied: A single Mg2+ is bound in site II of the digoxin and ouabain complexes, whereas both sites are occupied by K+ in the E2P–bufalin complex. In all complexes, αM4 adopts a wound form, characteristic for the E2P state and favorable for high-affinity CTS binding. We conclude that the occupants of the cation-binding site and the type of the lactone substituent determine the arrangement of αM4 and hypothesize that winding/unwinding of αM4 represents a trigger for high-affinity CTS binding. We find that the level of glycosylation affects the depth of CTS binding and that the steroid core substituent fine tune the configurationof transmembrane helices αM1–2.",
keywords = "Na/K-ATPase, phosphoenzyme, inhibitor, cardiac glycosides, structure",
author = "Mette Laursen and Gregersen, {Jonas Lindholt} and Laure Yatime and Poul Nissen and Natalya Fedosova",
year = "2015",
month = "2",
day = "10",
doi = "10.1073/pnas.1422997112",
language = "English",
volume = "112",
pages = "1755--1760",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
publisher = "The National Academy of Sciences of the United States of America",
number = "6",

}

RIS

TY - JOUR

T1 - Structures and characterization of digoxin- and bufalin-bound Na+,K+-ATPase compared with the ouabain-bound complex

AU - Laursen, Mette

AU - Gregersen, Jonas Lindholt

AU - Yatime, Laure

AU - Nissen, Poul

AU - Fedosova, Natalya

PY - 2015/2/10

Y1 - 2015/2/10

N2 - Cardiotonic steroids (CTSs) are specific and potent inhibitors of the Na+,K+-ATPase, with highest affinity to the phosphoenzyme (E2P) forms. CTSs are comprised of a steroid core, which can be glycosylated, and a varying number of substituents, including a five- or six-membered lactone. These functionalities have specific influence on the binding properties. We report crystal structures of the Na+,K+-ATPase in the E2P form in complex with bufalin (a nonglycosylated CTS with a six-membered lactone) and digoxin (a trisaccharide-conjugated CTS with a five-membered lactone) and compare their characteristics and binding kinetics with the previously described E2P–ouabain complex to derive specific details and the general mechanism of CTS binding and inhibition. CTSs block the extracellular cation exchange pathway, and cation-binding sites I and II are differently occupied: A single Mg2+ is bound in site II of the digoxin and ouabain complexes, whereas both sites are occupied by K+ in the E2P–bufalin complex. In all complexes, αM4 adopts a wound form, characteristic for the E2P state and favorable for high-affinity CTS binding. We conclude that the occupants of the cation-binding site and the type of the lactone substituent determine the arrangement of αM4 and hypothesize that winding/unwinding of αM4 represents a trigger for high-affinity CTS binding. We find that the level of glycosylation affects the depth of CTS binding and that the steroid core substituent fine tune the configurationof transmembrane helices αM1–2.

AB - Cardiotonic steroids (CTSs) are specific and potent inhibitors of the Na+,K+-ATPase, with highest affinity to the phosphoenzyme (E2P) forms. CTSs are comprised of a steroid core, which can be glycosylated, and a varying number of substituents, including a five- or six-membered lactone. These functionalities have specific influence on the binding properties. We report crystal structures of the Na+,K+-ATPase in the E2P form in complex with bufalin (a nonglycosylated CTS with a six-membered lactone) and digoxin (a trisaccharide-conjugated CTS with a five-membered lactone) and compare their characteristics and binding kinetics with the previously described E2P–ouabain complex to derive specific details and the general mechanism of CTS binding and inhibition. CTSs block the extracellular cation exchange pathway, and cation-binding sites I and II are differently occupied: A single Mg2+ is bound in site II of the digoxin and ouabain complexes, whereas both sites are occupied by K+ in the E2P–bufalin complex. In all complexes, αM4 adopts a wound form, characteristic for the E2P state and favorable for high-affinity CTS binding. We conclude that the occupants of the cation-binding site and the type of the lactone substituent determine the arrangement of αM4 and hypothesize that winding/unwinding of αM4 represents a trigger for high-affinity CTS binding. We find that the level of glycosylation affects the depth of CTS binding and that the steroid core substituent fine tune the configurationof transmembrane helices αM1–2.

KW - Na/K-ATPase

KW - phosphoenzyme

KW - inhibitor

KW - cardiac glycosides

KW - structure

U2 - 10.1073/pnas.1422997112

DO - 10.1073/pnas.1422997112

M3 - Journal article

VL - 112

SP - 1755

EP - 1760

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 6

ER -