Archaeal protein containing domain of unknown function 2193 undergoes oligomeric reconfiguration upon iron-sulfur cluster binding.

Abstract

Methanogenic archaea are particularly rich in iron-sulfur proteins, yet their roles remain largely enigmatic. Here, we characterized a Methanococcus voltae (Mvo) protein from the domain of unknown function (DUF) 2193 family, a group of proteins present primarily in archaea and characterized by a conserved cysteine-rich C-terminal motif. MvoDUF2193 was heterologously expressed and characterized by a range of spectroscopic and analytical methods. The results demonstrate that MvoDUF2193 binds a single [4Fe-4S] cluster per subunit and that cluster occupancy regulates the transition from an apo tetramer to a [4Fe-4S] monomeric form. We hypothesize that MvoDUF2193 serves a regulatory role in the cell, mediated by [Fe-S] cluster binding and changes in oligomeric state.