2QY2
Characterization of a trifunctional mimivirus mRNA capping enzyme and crystal structure of the RNA triphosphatase domainm.
Summary for 2QY2
| Entry DOI | 10.2210/pdb2qy2/pdb |
| Related | 2QZE 3BGY |
| Descriptor | Probable mRNA-capping enzyme, ACETATE ION, CITRATE ANION, ... (4 entities in total) |
| Functional Keywords | mrna capping, phosphatase, beta tunnel, viral protein, hydrolase, mrna processing, multifunctional enzyme, nucleotidyltransferase, s-adenosyl-l-methionine, transferase |
| Biological source | Mimivirus |
| Cellular location | Virion: Q5UQX1 |
| Total number of polymer chains | 2 |
| Total formula weight | 55601.94 |
| Authors | Shuman, S.,Benarroch, D.,Smith, P. (deposition date: 2007-08-13, release date: 2008-04-01, Last modification date: 2024-02-21) |
| Primary citation | Benarroch, D.,Smith, P.,Shuman, S. Characterization of a trifunctional mimivirus mRNA capping enzyme and crystal structure of the RNA triphosphatase domain. Structure, 16:501-512, 2008 Cited by PubMed Abstract: The RNA triphosphatase (RTPase) components of the mRNA capping apparatus are a bellwether of eukaryal taxonomy. Fungal and protozoal RTPases belong to the triphosphate tunnel metalloenzyme (TTM) family, exemplified by yeast Cet1. Several large DNA viruses encode metal-dependent RTPases unrelated to the cysteinyl-phosphatase RTPases of their metazoan host organisms. The origins of DNA virus RTPases are unclear because they are structurally uncharacterized. Mimivirus, a giant virus of amoeba, resembles poxviruses in having a trifunctional capping enzyme composed of a metal-dependent RTPase module fused to guanylyltransferase (GTase) and guanine-N7 methyltransferase domains. The crystal structure of mimivirus RTPase reveals a minimized tunnel fold and an active site strikingly similar to that of Cet1. Unlike homodimeric fungal RTPases, mimivirus RTPase is a monomer. The mimivirus TTM-type RTPase-GTase fusion resembles the capping enzymes of amoebae, providing evidence that the ancestral large DNA virus acquired its capping enzyme from a unicellular host. PubMed: 18400173DOI: 10.1016/j.str.2008.01.009 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2 Å) |
Structure validation
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