2025/09/05 by Seigo Shima, James A. Birrell, Sven T. Stripp +2 · 1 voice
Energy · Materials Science · #Metalloenzymes and iron-sulfur proteins #Electrocatalysts for Energy Conversion #Hydrogen Storage and Materials
paper · doi:10.1002/9783527843596.ch15
During evolution, three types of H 2 -activating enzymes have evolved, namely the [Fe]-, [FeFe]-, and [NiFe]-hydrogenases. All three enzymes contain thiol-coordinated iron ions and at least one iron-bound carbon monoxide at their active site and catalyze the cleavage of H 2 into a hydride (H − ) and a proton (H + ). In contrast to [Fe]-hydrogenases, which mediate the hydride transfer from H 2 to methenyl-tetrahydromethanopterin to form methylene-tetrahydromethanopterin, a central step in methanogenesis, [FeFe]- and [NiFe]-hydrogenases enable the complete, but reversible conversion of H 2 into 2 H + and 2 e − , which in most cases contributes to the energy metabolism of their microbial hosts. Although catalyzing a seemingly simple chemical reaction, the catalytic cycles involve a large number of redox intermediates, which despite some similarities, differ in the three classes of hydrogenase. Therefore, in this chapter, the details of the catalytic cycles of the hydrogenases, whose identification required decades of research, are treated separately in three parts, by Seigo Shima for [Fe]-hydrogenases (Section 15.1), James Birrell and Sven Stripp for [FeFe]-hydrogenases (Section 15.2), and Giorgio Caserta and Oliver Lenz for [NiFe]-hydrogenases (Section 15.3).