Change search
Link to record
Permanent link

Direct link
Gupta, Arun A.
Alternative names
Publications (3 of 3) Show all publications
Gupta, A. A., Reinartz, I., Karunanithy, G., Spilotros, A., Jonna, V. R., Hofer, A., . . . Wolf-Watz, M. (2018). Formation of a Secretion-Competent Protein Complex by a Dynamic Wrap-around Binding Mechanism. Journal of Molecular Biology, 430(18, Part B), 3157-3169
Open this publication in new window or tab >>Formation of a Secretion-Competent Protein Complex by a Dynamic Wrap-around Binding Mechanism
Show others...
2018 (English)In: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 430, no 18, Part B, p. 3157-3169Article in journal (Refereed) Published
Abstract [en]

Bacterial virulence is typically initiated by translocation of effector or toxic proteins across host cell membranes. A class of gram-negative pathogenic bacteria including Yersinia pseudotuberculosis and Yersinia pestis accomplishes this objective with a protein assembly called the type III secretion system. Yersinia effector proteins (Yop) are presented to the translocation apparatus through formation of specific complexes with their cognate chaperones (Syc). In the complexes where the structure is available, the Yops are extended and wrap around their cognate chaperone. This structural architecture enables secretion of the Yop from the bacterium in early stages of translocation. It has been shown previously that the chaperone-binding domain of YopE is disordered in its isolation but becomes substantially more ordered in its wrap-around complex with its chaperone SycE. Here, by means of NMR spectroscopy, small-angle X-ray scattering and molecular modeling, we demonstrate that while the free chaperone-binding domain of YopH (YopHCBD) adopts a fully ordered and globular fold, it populates an elongated, wrap-around conformation when it engages in a specific complex with its chaperone SycH2. Hence, in contrast to YopE that is unstructured in its free state, YopH transits from a globular free state to an elongated chaperone-bound state. We demonstrate that a sparsely populated YopHCBD state has an elevated affinity for SycH2 and represents an intermediate in the formation of the protein complex. Our results suggest that Yersinia has evolved a binding mechanism where SycH2 passively stimulates an elongated YopH conformation that is presented to the type III secretion system in a secretion-competent conformation.

Place, publisher, year, edition, pages
Elsevier, 2018
NMR spectroscopy, protein complex, binding mechanism
National Category
Biochemistry and Molecular Biology
urn:nbn:se:umu:diva-151495 (URN)10.1016/j.jmb.2018.07.014 (DOI)000444668100010 ()
Swedish Research Council, 2013-5954Knut and Alice Wallenberg FoundationCarl Tryggers foundation , CTS 15:210The Kempe Foundations
Available from: 2018-09-05 Created: 2018-09-05 Last updated: 2018-10-04Bibliographically approved
Gupta, A., Reinartz, I., Spilotros, A., Jonna, V. R., Hofer, A., Svergun, D. I., . . . Wolf-Watz, M. (2017). Global Disordering in Stereo-Specific Protein Association. Paper presented at 61st Annual Meeting of the Biophysical-Society, FEB 11-15, 2017, New Orleans, LA. Biophysical Journal, 112(3), 33A-33A
Open this publication in new window or tab >>Global Disordering in Stereo-Specific Protein Association
Show others...
2017 (English)In: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 112, no 3, p. 33A-33AArticle in journal, Meeting abstract (Refereed) Published
Place, publisher, year, edition, pages
National Category
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
urn:nbn:se:umu:diva-137015 (URN)000402328000166 ()
61st Annual Meeting of the Biophysical-Society, FEB 11-15, 2017, New Orleans, LA
Available from: 2017-06-29 Created: 2017-06-29 Last updated: 2018-06-09Bibliographically approved
Zhang, J., Li, Y., Gupta, A. A., Nam, K. & Andersson, P. L. (2016). Identification and Molecular Interaction Studies of Thyroid Hormone Receptor Disruptors among Household Dust Contaminants. Chemical Research in Toxicology, 29(8), 1345-1354
Open this publication in new window or tab >>Identification and Molecular Interaction Studies of Thyroid Hormone Receptor Disruptors among Household Dust Contaminants
Show others...
2016 (English)In: Chemical Research in Toxicology, ISSN 0893-228X, E-ISSN 1520-5010, Vol. 29, no 8, p. 1345-1354Article in journal (Refereed) Published
Abstract [en]

Thyroid hormone disrupting chemicals (THDCs), often found abundantly in the environment, interfere with normal thyroid hormone signaling and induce physiological malfunctions, possibly by affecting thyroid hormone receptors (THRs). Indoor dust ingestion is a significant human exposure route of THDCs, raising serious concerns for human health. Here, we developed a virtual screening protocol based on an ensemble of X-ray crystallographic structures of human THRβ1 and the generalized Born solvation model to identify potential THDCs targeting the human THRβ1 isoform. The protocol was applied to virtually screen an in-house indoor dust contaminant inventory, yielding 31 dust contaminants as potential THRβ1 binders. Five predicted binders and one negative control were tested using isothermal titration calorimetry, of which four, i.e., 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) ether (BADGE-HCl-H2O), 2,2',4,4'-tetrahydroxybenzophenone (BP2), and 2,4-dichlorophenoxyacetic acid (2,4-D), were identified as THRβ1 binders with binding affinities ranging between 60 μM and 460 μM. Molecular dynamics (MD) simulations were employed to examine potential binding modes of these binders and provided a rationale for explaining their specific recognition by THRβ1. The combination of in vitro binding affinity measurements and MD simulations allowed identification of four new potential THR-targeting THDCs that have been found in household dust. We suggest using the developed structure-based virtual screening protocol to identify and prioritize testing of potential THDCs.

National Category
Pharmacology and Toxicology
urn:nbn:se:umu:diva-125629 (URN)10.1021/acs.chemrestox.6b00171 (DOI)000381593500011 ()27410513 (PubMedID)2-s2.0-84982300220 (Scopus ID)
Available from: 2016-09-13 Created: 2016-09-13 Last updated: 2018-06-07Bibliographically approved

Search in DiVA

Show all publications