Preprint Hypothesis Version 1 This version is not peer-reviewed

Identification of a Novel Fumarate Reductase Potentially Involved in Electron Bifurcation

Version 1 : Received: 20 December 2019 / Approved: 22 December 2019 / Online: 22 December 2019 (01:47:29 CET)

How to cite: Van Kranenburg, R.; Koendjbiharie, J.G. Identification of a Novel Fumarate Reductase Potentially Involved in Electron Bifurcation. Preprints 2019, 2019120288 (doi: 10.20944/preprints201912.0288.v1). Van Kranenburg, R.; Koendjbiharie, J.G. Identification of a Novel Fumarate Reductase Potentially Involved in Electron Bifurcation. Preprints 2019, 2019120288 (doi: 10.20944/preprints201912.0288.v1).

Abstract

In the succinic acid-producing bacterium Pseudoclostridium thermosuccinogenes the fumarate reductase (FRD) genes reside in an operon together with those encoding an electron bifurcating complex (FlxABCD-HdrABC) that shuttles electrons from NADH to ferredoxin and a disulfide bond. Based on phylogeny and genomic co-occurrence we propose two hypothetical mechanisms via which the FRD is involved in electron bifurcation: (I) A disulfide bond from a hitherto unknown cofactor is reduced by the electron-bifurcating FlxABCD-HdrABC complex, using NADH to generate two thiol groups, while facilitating the unfavourable reduction of ferredoxin by NADH. The disulfide bond is subsequently regenerated via the reduction of fumarate by the FRD using the previously formed thiol groups. (II) The FRD forms an integral part of the FlxABCD-HdrABC complex, and NADH is used to reduce ferredoxin and fumarate directly, without an intermediate disulfide-forming cofactor. Either way enables the conservation of additional energy by a soluble FRD, analogous to fumarate respiration.

Subject Areas

Pseudoclostridium thermosuccinogenes; fumarate reductase; FRD; electron-bifurcation

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.