The Bacterial [Fe]‐Hydrogenase Paralog HmdII Uses Tetrahydrofolate Derivatives as Substrates. Issue 11 (25th January 2019)

• Record Type: Journal Article
• Authors: Watanabe, Tomohiro; Wagner, Tristan; Huang, Gangfeng; Kahnt, Jörg; Ataka, Kenichi; Ermler, Ulrich; Shima, Seigo
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 11(2019)
• Page Start: 3506
• Page End: 3510
• Publication Date: 2019-01-25
• Subjects: FeGP cofactor -- metalloenzymes -- protein structure -- tetrahydrofolate -- tetrahydromethanopterin; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201813465
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: [Fe]‐hydrogenase (Hmd) catalyzes the reversible hydrogenation of methenyl‐tetrahydromethanopterin (methenyl‐H4 MPT + ) with H2 . H4 MPT is a C1‐carrier of methanogenic archaea. One bacterial genus, Desulfurobacterium, contains putative genes for the Hmd paralog, termed HmdII, and the HcgA–G proteins. The latter are required for the biosynthesis of the prosthetic group of Hmd, the iron–guanylylpyridinol (FeGP) cofactor. This finding is intriguing because Hmd and HmdII strictly use H4 MPT derivatives that are absent in most bacteria. We identified the presence of the FeGP cofactor in D. thermolithotrophum . The bacterial HmdII reconstituted with the FeGP cofactor catalyzed the hydrogenation of derivatives of tetrahydrofolate, the bacterial C1‐carrier, albeit with low enzymatic activities. The crystal structures show how Hmd recognizes tetrahydrofolate derivatives. These findings have an impact on future biotechnology by identifying a bacterial Hmd paralog. Abstract : [Fe]‐hydrogenase (Hmd) catalyzes the hydrogenation of methenyl‐tetrahydromethanopterin (methenyl‐H4 MPT + ). H4 MPT is a C1‐carrier of methanogenic archaea. One bacterial genus contains the Hmd paralog, HmdII. Bacterial HmdII catalyzes the hydrogenation of derivatives of the bacterial C1‐carrier, tetrahydrofolate. The crystal structure of HmdII explains the evolutionary adaptation to the different hydride‐accepting substrate.