TtcA a new tRNA-thioltransferase with an Fe-S cluster. Issue 12 (26th June 2014)

• Record Type: Journal Article
• Authors: Bouvier, Denis; Labessan, Natty; Clémancey, Martin; Latour, Jean-Marc; Ravanat, Jean-Luc; Fontecave, Marc; Atta, Mohamed
• Is Part Of: Nucleic acids research. Volume 42:Issue 12(2014)
• Page Start: 7960
• Page End: 7970
• Publication Date: 2014-06-26
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gku508
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract : TtcA catalyzes the post-transcriptional thiolation of cytosine 32 in some tRNAs. The enzyme from Escherichia coli was homologously overexpressed in E. coli . The purified enzyme is a dimer containing an iron–sulfur cluster and displays activity in in vitro assays. The type and properties of the cluster were investigated using a combination of UV-visible absorption, EPR and Mössbauer spectroscopy, as well as by site-directed mutagenesis. These studies demonstrated that the TtcA enzyme contains a redox-active and oxygen-sensitive [4Fe-4S] cluster, chelated by only three cysteine residues and absolutely essential for activity. TtcA is unique tRNA-thiolating enzyme using an iron–sulfur cluster for catalyzing a non-redox reaction.