Bithionol Potently Inhibits Human Soluble Adenylyl Cyclase through Binding to the Allosteric Activator Site.

2.50
Hdl Handle:
http://hdl.handle.net/10033/620904
Title:
Bithionol Potently Inhibits Human Soluble Adenylyl Cyclase through Binding to the Allosteric Activator Site.
Authors:
Kleinboelting, Silke; Ramos-Espiritu, Lavoisier; Buck, Hannes; Colis, Laureen; van den Heuvel, Joop; Glickman, J Fraser; Levin, Lonny R; Buck, Jochen; Steegborn, Clemens
Abstract:
The signaling molecule cAMP regulates functions ranging from bacterial transcription to mammalian memory. In mammals, cAMP is synthesized by nine transmembrane adenylyl cyclases (ACs) and one soluble AC (sAC). Despite similarities in their catalytic domains, these ACs differ in regulation. Transmembrane ACs respond to G proteins, whereas sAC is uniquely activated by bicarbonate. Via bicarbonate regulation, sAC acts as a physiological sensor for pH/bicarbonate/CO2, and it has been implicated as a therapeutic target, e.g. for diabetes, glaucoma, and a male contraceptive. Here we identify the bisphenols bithionol and hexachlorophene as potent, sAC-specific inhibitors. Inhibition appears mostly non-competitive with the substrate ATP, indicating that they act via an allosteric site. To analyze the interaction details, we solved a crystal structure of an sAC·bithionol complex. The structure reveals that the compounds are selective for sAC because they bind to the sAC-specific, allosteric binding site for the physiological activator bicarbonate. Structural comparison of the bithionol complex with apo-sAC and other sAC·ligand complexes along with mutagenesis experiments reveals an allosteric mechanism of inhibition; the compound induces rearrangements of substrate binding residues and of Arg(176), a trigger between the active site and allosteric site. Our results thus provide 1) novel insights into the communication between allosteric regulatory and active sites, 2) a novel mechanism for sAC inhibition, and 3) pharmacological compounds targeting this allosteric site and utilizing this mode of inhibition. These studies provide support for the future development of sAC-modulating drugs.
Affiliation:
Helmholtz Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany.
Citation:
Bithionol Potently Inhibits Human Soluble Adenylyl Cyclase through Binding to the Allosteric Activator Site. 2016, 291 (18):9776-84 J. Biol. Chem.
Journal:
The Journal of biological chemistry
Issue Date:
29-Apr-2016
URI:
http://hdl.handle.net/10033/620904
DOI:
10.1074/jbc.M115.708255
PubMed ID:
26961873
Type:
Article
Language:
en
ISSN:
1083-351X
Appears in Collections:
publications of the research group recombinant protein expression (RPEX)

Full metadata record

DC FieldValue Language
dc.contributor.authorKleinboelting, Silkeen
dc.contributor.authorRamos-Espiritu, Lavoisieren
dc.contributor.authorBuck, Hannesen
dc.contributor.authorColis, Laureenen
dc.contributor.authorvan den Heuvel, Joopen
dc.contributor.authorGlickman, J Fraseren
dc.contributor.authorLevin, Lonny Ren
dc.contributor.authorBuck, Jochenen
dc.contributor.authorSteegborn, Clemensen
dc.date.accessioned2017-05-03T13:27:51Z-
dc.date.available2017-05-03T13:27:51Z-
dc.date.issued2016-04-29-
dc.identifier.citationBithionol Potently Inhibits Human Soluble Adenylyl Cyclase through Binding to the Allosteric Activator Site. 2016, 291 (18):9776-84 J. Biol. Chem.en
dc.identifier.issn1083-351X-
dc.identifier.pmid26961873-
dc.identifier.doi10.1074/jbc.M115.708255-
dc.identifier.urihttp://hdl.handle.net/10033/620904-
dc.description.abstractThe signaling molecule cAMP regulates functions ranging from bacterial transcription to mammalian memory. In mammals, cAMP is synthesized by nine transmembrane adenylyl cyclases (ACs) and one soluble AC (sAC). Despite similarities in their catalytic domains, these ACs differ in regulation. Transmembrane ACs respond to G proteins, whereas sAC is uniquely activated by bicarbonate. Via bicarbonate regulation, sAC acts as a physiological sensor for pH/bicarbonate/CO2, and it has been implicated as a therapeutic target, e.g. for diabetes, glaucoma, and a male contraceptive. Here we identify the bisphenols bithionol and hexachlorophene as potent, sAC-specific inhibitors. Inhibition appears mostly non-competitive with the substrate ATP, indicating that they act via an allosteric site. To analyze the interaction details, we solved a crystal structure of an sAC·bithionol complex. The structure reveals that the compounds are selective for sAC because they bind to the sAC-specific, allosteric binding site for the physiological activator bicarbonate. Structural comparison of the bithionol complex with apo-sAC and other sAC·ligand complexes along with mutagenesis experiments reveals an allosteric mechanism of inhibition; the compound induces rearrangements of substrate binding residues and of Arg(176), a trigger between the active site and allosteric site. Our results thus provide 1) novel insights into the communication between allosteric regulatory and active sites, 2) a novel mechanism for sAC inhibition, and 3) pharmacological compounds targeting this allosteric site and utilizing this mode of inhibition. These studies provide support for the future development of sAC-modulating drugs.en
dc.language.isoenen
dc.rights.urihttp://creativecommons.org/licenses/by-nc-sa/4.0/*
dc.subject.meshAdenosine Triphosphateen
dc.subject.meshAdenylyl Cyclasesen
dc.subject.meshAllosteric Regulationen
dc.subject.meshBicarbonatesen
dc.subject.meshBithionolen
dc.subject.meshCatalytic Domainen
dc.subject.meshCrystallography, X-Rayen
dc.subject.meshHumansen
dc.titleBithionol Potently Inhibits Human Soluble Adenylyl Cyclase through Binding to the Allosteric Activator Site.en
dc.typeArticleen
dc.contributor.departmentHelmholtz Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany.en
dc.identifier.journalThe Journal of biological chemistryen

Related articles on PubMed

This item is licensed under a Creative Commons License
Creative Commons
All Items in HZI are protected by copyright, with all rights reserved, unless otherwise indicated.