skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics

Abstract

Thioredoxins (Trxs) are small ubiquitous proteins that participate in a diverse variety of redox reactions via the reversible oxidation of two cysteine thiol groups in a structurally conserved active site, CGPC. Here, we describe the NMR solution structures of a Trx from Ehrlichia chaffeensis (Ec-Trx, ECH_0218), the etiological agent responsible for human monocytic ehrlichiosis, in both the oxidized and reduced states. The overall topology of the calculated structures is similar in both redox states and similar to other Trx structures, a five-strand, mixed -sheet (1:3:2:4:5) surrounded by four -helices. Unlike other Trxs studied by NMR in both redox states, the 1H-15N HSQC spectra of reduced Ec-Trx was missing eight amide cross peaks relative to the spectra of oxidized Ec-Trx. These missing amides correspond to residues C32-E39 in the active site containing helix (2) and S72-I75 in a loop near the active site and suggest a substantial change in the backbone dynamics associated with the formation of an intramolecular C32-C35 disulfide bond.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1415689
Report Number(s):
PNNL-SA-126464
Journal ID: ISSN 2053-230X; 50089; 49703; 49153; 48233; 48683; 453040220
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Crystallographica. Section F, Structural Biology Communications; Journal Volume: 74; Journal Issue: 1; Related Information: pages 46-56
Country of Publication:
United States
Language:
English
Subject:
infectious diseases; structural biology; NMR spectroscopy; molecular dynamics; SSGCID; Environmental Molecular Sciences Laboratory

Citation Formats

Buchko, Garry W., Hewitt, Stephen N., Van Voorhis, Wesley C., and Myler, Peter J. Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics. United States: N. p., 2018. Web. doi:10.1107/S2053230X1701799X.
Buchko, Garry W., Hewitt, Stephen N., Van Voorhis, Wesley C., & Myler, Peter J. Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics. United States. doi:10.1107/S2053230X1701799X.
Buchko, Garry W., Hewitt, Stephen N., Van Voorhis, Wesley C., and Myler, Peter J. Tue . "Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics". United States. doi:10.1107/S2053230X1701799X.
@article{osti_1415689,
title = {Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics},
author = {Buchko, Garry W. and Hewitt, Stephen N. and Van Voorhis, Wesley C. and Myler, Peter J.},
abstractNote = {Thioredoxins (Trxs) are small ubiquitous proteins that participate in a diverse variety of redox reactions via the reversible oxidation of two cysteine thiol groups in a structurally conserved active site, CGPC. Here, we describe the NMR solution structures of a Trx from Ehrlichia chaffeensis (Ec-Trx, ECH_0218), the etiological agent responsible for human monocytic ehrlichiosis, in both the oxidized and reduced states. The overall topology of the calculated structures is similar in both redox states and similar to other Trx structures, a five-strand, mixed -sheet (1:3:2:4:5) surrounded by four -helices. Unlike other Trxs studied by NMR in both redox states, the 1H-15N HSQC spectra of reduced Ec-Trx was missing eight amide cross peaks relative to the spectra of oxidized Ec-Trx. These missing amides correspond to residues C32-E39 in the active site containing helix (2) and S72-I75 in a loop near the active site and suggest a substantial change in the backbone dynamics associated with the formation of an intramolecular C32-C35 disulfide bond.},
doi = {10.1107/S2053230X1701799X},
journal = {Acta Crystallographica. Section F, Structural Biology Communications},
number = 1,
volume = 74,
place = {United States},
year = {Tue Jan 02 00:00:00 EST 2018},
month = {Tue Jan 02 00:00:00 EST 2018}
}