5mkq

TtuA enzyme containing a [4Fe-4S]

spinqualitylabelsall models 5mkq, resolution 2.79Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5mkq is a 2 chain structure with sequence from Pyrococcus horikoshii OT3. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.79Å Ligands: SF4, ZN Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function TTUA_PYRHO Catalyzes the ATP-dependent 2-thiolation of 5-methyluridine residue at position 54 in the T loop of tRNAs, leading to 5-methyl-2-thiouridine (m(5)s(2)U or s(2)T) (PubMed:28655838). This modification allows thermal stabilization of tRNAs in thermophilic microorganisms, and is required for cell growth at high temperatures (By similarity). Can use free sulfide as sulfur source in vitro, which may be also the sulfur source in vivo (PubMed:28655838).[UniProtKB:Q72LF3] Publication Abstract from PubMed Sulfur is present in several nucleosides within tRNAs. In particular, thiolation of the universally conserved methyl-uridine at position 54 stabilizes tRNAs from thermophilic bacteria and hyperthermophilic archaea and is required for growth at high temperature. The simple nonredox substitution of the C2-uridine carbonyl oxygen by sulfur is catalyzed by tRNA thiouridine synthetases called TtuA. Spectroscopic, enzymatic, and structural studies indicate that TtuA carries a catalytically essential [4Fe-4S] cluster and requires ATP for activity. A series of crystal structures shows that (i) the cluster is ligated by only three cysteines that are fully conserved, allowing the fourth unique iron to bind a small ligand, such as exogenous sulfide, and (ii) the ATP binding site, localized thanks to a protein-bound AMP molecule, a reaction product, is adjacent to the cluster. A mechanism for tRNA sulfuration is suggested, in which the unique iron of the catalytic cluster serves to bind exogenous sulfide, thus acting as a sulfur carrier. Nonredox thiolation in tRNA occurring via sulfur activation by a [4Fe-4S] cluster.,Arragain S, Bimai O, Legrand P, Caillat S, Ravanat JL, Touati N, Binet L, Atta M, Fontecave M, Golinelli-Pimpaneau B Proc Natl Acad Sci U S A. 2017 Jul 11;114(28):7355-7360. doi:, 10.1073/pnas.1700902114. Epub 2017 Jun 27. PMID:28655838 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA