7LC5
Crystal structure of epoxyqueuosine reductase QueH from Thermotoga maritima
Summary for 7LC5
| Entry DOI | 10.2210/pdb7lc5/pdb |
| Descriptor | Epoxyqueuosine reductase QueH, IRON/SULFUR CLUSTER, FE (III) ION, ... (5 entities in total) |
| Functional Keywords | epoxyqueuosine reductase, queh, iron-sulfur cluster, queuosine, trna, oxidoreductase |
| Biological source | Thermotoga maritima MSB8 |
| Total number of polymer chains | 1 |
| Total formula weight | 22991.81 |
| Authors | Li, Q.,Bruner, S.D. (deposition date: 2021-01-09, release date: 2021-11-03, Last modification date: 2024-05-22) |
| Primary citation | Li, Q.,Zallot, R.,MacTavish, B.S.,Montoya, A.,Payan, D.J.,Hu, Y.,Gerlt, J.A.,Angerhofer, A.,de Crecy-Lagard, V.,Bruner, S.D. Epoxyqueuosine Reductase QueH in the Biosynthetic Pathway to tRNA Queuosine Is a Unique Metalloenzyme. Biochemistry, 60:3152-3161, 2021 Cited by PubMed Abstract: Queuosine is a structurally unique and functionally important tRNA modification, widely distributed in eukaryotes and bacteria. The final step of queuosine biosynthesis is the reduction/deoxygenation of epoxyqueuosine to form the cyclopentene motif of the nucleobase. The chemistry is performed by the structurally and functionally characterized cobalamin-dependent QueG. However, the gene is absent from several bacteria that otherwise retain queuosine biosynthesis machinery. Members of the IPR003828 family (previously known as DUF208) have been recently identified as nonorthologous replacements of QueG, and this family was renamed QueH. Here, we present the structural characterization of QueH from . The structure reveals an unusual active site architecture with a [4Fe-4S] metallocluster along with an adjacent coordinated iron metal. The juxtaposition of the cofactor and coordinated metal ion predicts a unique mechanism for a two-electron reduction/deoxygenation of epoxyqueuosine. To support the structural characterization, biochemical and genomic analyses are presented. Overall, this work reveals new diversity in the chemistry of iron/sulfur-dependent enzymes and novel insight into the last step of this widely conserved tRNA modification. PubMed: 34652139DOI: 10.1021/acs.biochem.1c00164 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.5 Å) |
Structure validation
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