Modomics - A Database of RNA Modifications

ID Card:

Full name: tRNA-specific adenosine deaminase
Synonym: SAV0558
GI: 15923548
COG: COG0590
UniProt: Q99W51
Structures: | 2B3J |
Alpha Fold Predicted Structure: AF-Q99W51-F1
Enzyme type: deaminase predicted
Position of modification - modification: t:34 - I

PDB Structures:


Structure Description:


Abstract of the PDB Structure's related Publication:

Bacterial tRNA adenosine deaminases (TadAs) catalyze the hydrolytic deamination of adenosine to inosine at the wobble position of tRNA(Arg2), a process that enables this single tRNA to recognize three different arginine codons in mRNA. In addition, inosine is also introduced at the wobble position of multiple eukaryotic tRNAs. The genes encoding these deaminases are essential in bacteria and yeast, demonstrating the importance of their biological activity. Here we report the crystallization and structure determination to 2.0 A of Staphylococcus aureus TadA bound to the anticodon stem-loop of tRNA(Arg2) bearing nebularine, a non-hydrolyzable adenosine analog, at the wobble position. The cocrystal structure reveals the basis for both sequence and structure specificity in the interactions of TadA with RNA, and it additionally provides insight into the active site architecture that promotes efficient hydrolytic deamination.

Download RCSB-PDB Structures:

Pdb Files   2B3J.pdb  
Pdbx/mmCIF Files   2B3J.cif  

Protein sequence:



The homologue from E. coli was biochemically characterized.

Alpha Fold Predicted Structure:

Clear Selection and Reset Camera

Protein sequence:

Secondary Structure Alphabet

  • G: 3-turn helix (310helix)
  • H: α-helix
  • I: 𝝅-helix (5 - turn helix)
  • T: Hydrogen Bonded Turn
  • B: β-sheet
  • S: Bend
  • C: Coil (residues not present in any of the above conformations)
  • N: Not assigned

Download PDB Structures & DSSP Secondary Structures:

Alpha Fold Pdb Files   AF-Q99W51-F1.pdb  
Alpha Fold Pdbx/mmCIF Files   AF-Q99W51-F1.cif  


Title Authors Journal Details PubMed Id DOI
Crystal structure of Staphylococcus aureus tRNA adenosine deaminase TadA in complex with RNA. Losey HC, Ruthenburg AJ, Verdine GL Nat Struct Mol Biol [details] 16415880 -