Iron–sulfur biology invades tRNA modification: the case of U34 sulfuration. Issue 7 (21st March 2021)

• Record Type: Journal Article
• Authors: Zhou, Jingjing; Lénon, Marine; Ravanat, Jean-Luc; Touati, Nadia; Velours, Christophe; Podskoczyj, Karolina; Leszczynska, Grazyna; Fontecave, Marc; Barras, Frédéric; Golinelli-Pimpaneau, Béatrice
• Is Part Of: Nucleic acids research. Volume 49:Issue 7(2021)
• Page Start: 3997
• Page End: 4007
• Publication Date: 2021-03-21
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gkab138
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract: Sulfuration of uridine 34 in the anticodon of tRNAs is conserved in the three domains of life, guaranteeing fidelity of protein translation. In eubacteria, it is catalyzed by MnmA-type enzymes, which were previously concluded not to depend on an iron–sulfur [Fe–S] cluster. However, we report here spectroscopic and iron/sulfur analysis, as well as in vitro catalytic assays and site-directed mutagenesis studies unambiguously showing that MnmA from Escherichia coli can bind a [4Fe–4S] cluster, which is essential for sulfuration of U34-tRNA. We propose that the cluster serves to bind and activate hydrosulfide for nucleophilic attack on the adenylated nucleoside. Intriguingly, we found that E. coli cells retain s 2 U34 biosynthesis in the Δ iscUA Δ sufABCDSE strain, lacking functional ISC and SUF [Fe–S] cluster assembly machineries, thus suggesting an original and yet undescribed way of maturation of MnmA. Moreover, we report genetic analysis showing the importance of MnmA for sustaining oxidative stress.