Spectroscopic and Structural Characterization of Reduced Desulfovibrio vulgaris Hildenborough W-FdhAB Reveals Stable Metal Coordination during Catalysis

Funding Information: This work was financially supported by Fundação para a Ciência e Tecnologia (FCT, Portugal) through fellowship SFRH/BD/116515/2016, COVID/BD/151766/2021, grant PTDC/BII-BBF/2050/2020, R&D units MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020) and UCIBIO (UIDP/04378/2020 and UIDB/04378/2020), and associated laboratories LS4FUTURE (LA/P/0087/2020) and i4HB (LA/P/0140/2020). European Union’s Horizon 2020 research and innovation program (grant agreement no. 810856) is also acknowledged. This work was also funded by the French national research agency (ANR─MOLYERE project, grant number 16-CE-29-0010-01) and supported by the computing facilities of the CRCMM, “Centre Régional de Compétences en Modélisation Moléculaire de Marseille”. The authors are grateful to the EPR facilities at the French EPR network RENARD (IR CNRS 3443, now INFRANALYTICS, FR2054) and the Aix-Marseille University EPR center. Publisher Copyright: © 2022 American Chemical Society. All rights reserved.Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO2reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Desulfovibrio vulgaris Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe-4S]1+clusters, and full reduction requires Ti(III)-citrate. The redox potentials of the four [4Fe-4S]1+centers range between -250 and -530 mV. Two distinct WVsignals were detected, WDVand WFV, which differ in only the g2-value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of WVI/Vwas determined to be -370 mV when reduced by dithionite and -340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate WVstate of FdhAB.publishersversionpublishe

Standardisation of synovial biopsy analyses in rheumatic diseases: a consensus of the EULAR Synovitis and OMERACT Synovial Tissue Biopsy Groups

Following publication of the original article [1], the authors reported an error in the spelling of the ninth author’s name. Incorrect spelling: Soeren Andreas Just. Correct spelling: Søren Andreas Just. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: The aim of this global collaboration was to develop a consensual set of items for the analysis of synovial biopsies in clinical practice and translational research through the EULAR Synovitis Study Group (ESSG) and OMERACT Synovial Tissue Biopsy Group. Methods: Participants were consulted through a modified Delphi method. Three sequential rounds occurred over 12 months. Members were sent a written questionnaire containing items divided into two parts. Items were identified and formulated based on a scoping review. The first part of the questionnaire referred to synovial biopsies in clinical practice including five subsections, and the second part to translational research with six subsections. Every participant was asked to score each item on a 5-point Likert scale. Items with a median score above 3.5 and a >70% agreement were selected for the next round. The last round was conducted orally at EULAR in June 2017. Results: Twenty-seven participants from 19 centers were contacted by email. Twenty participants from 17 centers answered. Response rates for next rounds were 100%. For the first part relating to clinical practice, 20/44 items (45.5%) were selected. For the second part relating to translational research, 18/43 items (41.9%) were selected for the final set. Conclusions: We herein propose a consensual set of analysis items to be used for synovial biopsies conducted in clinical practice and translational research. Correction: Following publication of the original article [1], the authors reported an error in the spelling of the ninth author's name

Correction to: Standardisation of synovial biopsy analyses in rheumatic diseases: a consensus of the EULAR Synovitis and OMERACT Synovial Tissue Biopsy Groups

Following publication of the original article [1], the authors reported an error in the spelling of the ninth author’s name