Show simple item record

dc.contributor.authorSchuler, Dominik
dc.contributor.authorLubker, Carolin
dc.contributor.authorLushington, Gerald H.
dc.contributor.authorTang, Wei-Jen
dc.contributor.authorShen, Yuequan
dc.contributor.authorRichter, Mark
dc.contributor.authorSeifert, Roland
dc.date.accessioned2017-01-27T20:42:25Z
dc.date.available2017-01-27T20:42:25Z
dc.date.issued2012-01-13
dc.identifier.citationSchuler, Dominik, Carolin Lübker, Gerald H. Lushington, Wei-Jen Tang, Yuequan Shen, Mark Richter, and Roland Seifert. "Interactions of Bordetella Pertussis Adenylyl Cyclase Toxin CyaA with Calmodulin Mutants and Calmodulin Antagonists: Comparison with Membranous Adenylyl Cyclase I." Biochemical Pharmacology 83.7 (2012): 839-48.en_US
dc.identifier.urihttp://hdl.handle.net/1808/22686
dc.description.abstractThe adenylyl cyclase (AC) toxin CyaA from Bordetella pertussis constitutes an important virulence factor for the pathogenesis of whooping cough. CyaA is activated by calmodulin (CaM) and compromises host defense by excessive cAMP production. Hence, pharmacological modulation of the CyaA/CaM interaction could constitute a promising approach to treat whooping cough, provided that interactions of endogenous effector proteins with CaM are not affected. As a first step toward this ambitious goal we examined the interactions of CyaA with wild-type CaM and four CaM mutants in which most methionine residues were replaced by leucine residues and studied the effects of the CaM antagonists calmidazolium, trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). CyaA/CaM interaction was monitored by CaM-dependent fluorescence resonance energy transfer (FRET) between tryptophan residues in CyaA and 2′-(N-methylanthraniloyl)-3′-deoxy-adenosine 5′-triphosphate and catalytic activity. Comparison of the concentration/response curves of CaM and CaM mutants for FRET and catalysis revealed differences, suggesting a two-step activation mechanism of CyaA by CaM. Even in the absence of CaM, calmidazolium inhibited catalysis, and it did so according to a biphasic function. Trifluoperazine and W-7 did not inhibit FRET or catalysis. In contrast to CyaA, some CaM mutants were more efficacious than CaM at activating membranous AC isoform 1. The slope of CyaA activation by CaM was much steeper than of AC1 activation. Collectively, the two-step activation mechanism of CyaA by CaM offers opportunities for pharmacological intervention. The failure of classic CaM inhibitors to interfere with CyaA/CaM interactions and the different interactions of CaM mutants with CyaA and AC1 point to unique CyaA/CaM interactions.en_US
dc.publisherElsevieren_US
dc.rightsThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License 3.0 (CC BY-NC-ND 3.0 US), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.en_US
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/3.0/
dc.subjectBordetella pertussisen_US
dc.subjectAdenylyl cyclaseen_US
dc.subjectCalmodulinen_US
dc.subjectFluorescence spectroscopyen_US
dc.subjectCalmodulin antagonistsen_US
dc.titleInteractions of Bordetella pertussis adenylyl cyclase toxin CyaA with calmodulin mutants and calmodulin antagonists: Comparison with membranous adenylyl cyclase Ien_US
dc.typeArticleen_US
kusw.kuauthorRichter, Mar
kusw.kudepartmentMolecular Biosciencesen_US
dc.identifier.doi10.1016/j.bcp.2012.01.005en_US
kusw.oaversionScholarly/refereed, author accepted manuscripten_US
kusw.oapolicyThis item meets KU Open Access policy criteria.en_US
dc.rights.accessrightsopenAccess


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License 3.0 (CC BY-NC-ND 3.0 US), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
Except where otherwise noted, this item's license is described as: This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License 3.0 (CC BY-NC-ND 3.0 US), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.