A subclass of archaeal U8-tRNA sulfurases requires a [4Fe–4S] cluster for catalysis - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Access content directly
Journal Articles Nucleic Acids Research Year : 2022

A subclass of archaeal U8-tRNA sulfurases requires a [4Fe–4S] cluster for catalysis

Abstract

Sulfuration of uridine 8, in bacterial and archaeal tRNAs, is catalyzed by enzymes formerly known as ThiI, but renamed here TtuI. Two different classes of TtuI proteins, which possess a PP-loop-containing pyrophosphatase domain that includes a conserved cysteine important for catalysis, have been identified. The first class, as exemplified by the prototypic Escherichia coli enzyme, possesses an additional C-terminal rhodanese domain harboring a second cysteine, which serves to form a catalytic persulfide. Among the second class of TtuI proteins that do not possess the rhodanese domain, some archaeal proteins display a conserved CXXC + C motif. We report here spectroscopic and enzymatic studies showing that TtuI from Methanococcus maripaludis and Pyrococcus furiosus can assemble a [4Fe–4S] cluster that is essential for tRNA sulfuration activity. Moreover, structural modeling studies, together with previously reported mutagenesis experiments of M. maripaludis TtuI, indicate that the [4Fe–4S] cluster is coordinated by the three cysteines of the CXXC + C motif. Altogether, our results raise a novel mechanism for U8-tRNA sulfuration, in which the cluster is proposed to catalyze the transfer of sulfur atoms to the activated tRNA substrate.
Fichier principal
Vignette du fichier
gkac1156.pdf (2.56 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

hal-04106149 , version 1 (25-05-2023)

Identifiers

Cite

Nisha He, Jingjing Zhou, Ornella Bimai, Jonathan Oltmanns, Jean-Luc Ravanat, et al.. A subclass of archaeal U8-tRNA sulfurases requires a [4Fe–4S] cluster for catalysis. Nucleic Acids Research, 2022, 50 (22), pp.12969-12978. ⟨10.1093/nar/gkac1156⟩. ⟨hal-04106149⟩
0 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More