ATP-dependent substrate reduction at an [Fe8S9] double-cubane cluster

Proc Natl Acad Sci U S A. 2018 Mar 20;115(12):2994-2999. doi: 10.1073/pnas.1720489115. Epub 2018 Mar 5.

Abstract

Chemically demanding reductive conversions in biology, such as the reduction of dinitrogen to ammonia or the Birch-type reduction of aromatic compounds, depend on Fe/S-cluster-containing ATPases. These reductions are typically catalyzed by two-component systems, in which an Fe/S-cluster-containing ATPase energizes an electron to reduce a metal site on the acceptor protein that drives the reductive reaction. Here, we show a two-component system featuring a double-cubane [Fe8S9]-cluster [{Fe4S4(SCys)3}2(μ2-S)]. The double-cubane-cluster-containing enzyme is capable of reducing small molecules, such as acetylene (C2H2), azide (N3-), and hydrazine (N2H4). We thus present a class of metalloenzymes akin in fold, metal clusters, and reactivity to nitrogenases.

Keywords: ATPase; Fe/S-cluster; acetylene; electron transfer; nitrogenase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylene / metabolism
  • Adenosine Triphosphate / metabolism*
  • Cloning, Molecular
  • Firmicutes / metabolism
  • Gene Expression Regulation, Bacterial
  • Iron-Sulfur Proteins / metabolism*
  • Models, Molecular
  • Protein Conformation

Substances

  • Iron-Sulfur Proteins
  • Adenosine Triphosphate
  • Acetylene

Associated data

  • PDB/6ENO