Sulfur carrier ThiS/MoaD-like (IPR003749)

Short name: ThiS/MoaD-like

Overlapping homologous superfamilies

Family relationships


ThiS (thiaminS) is a 66 aa protein involved in sulphur transfer. ThiS is coded in the thiCEFSGH operon in Escherichia coli. This family of proteins have two conserved Glycines at the COOH terminus. Thiocarboxylate is formed at the last G in the activation process. Sulphur is transferred from ThiI to ThiS in a reaction catalysed by IscS [PMID: 10781607]. MoaD, a protein involved in sulphur transfer during molybdopterin synthesis, is about the same length and shows limited sequence similarity to ThiS. Both have the conserved GG at the COOH end.

ThiS/MoaD proteins serve as sulfur carriers in thiamine and tungsten/molybdenum cofactor biosynthesis. Proteins in this entry also include TtuB from Thermus thermophilus. TtuB functions as the sulfur donor in the sulfurtransferase reaction catalyzed by TtuA [PMID: 28439027]. It is also required for the 2-thiolation of 5-methyluridine residue at position 54 in the T loop of tRNAs, leading to 5-methyl-2-thiouridine (m5s2U or s2T). This modification allows thermal stabilization of tRNAs in thermophilic microorganisms, and is essential for cell growth at high temperatures [PMID: 16547008].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.