Modomics - A Database of RNA Modifications

ID Card:

Full name:	Queuine tRNA-ribosyltransferase catalytic subunit 1
Synonym:	QTRT1, TGUT
GI:	221218971
UniProt:	Q9BXR0
Structures:	\| 6H42 \| 6H45 \| 7NQ4 \|
Alpha Fold Predicted Structure:	AF-Q9BXR0-F1
Enzyme type:

PDB Structures:

6H42

Structure Description:

Title:
Classification:
Technique:

Abstract of the PDB Structure's related Publication:

RNA modifications have been implicated in diverse and important roles in all kingdoms of life with over 100 of them present on tRNAs. A prominent modification at the wobble base of four tRNAs is the 7-deaza-guanine derivative queuine which substitutes the guanine at position 34. This exchange is catalyzed by members of the enzyme class of tRNA guanine transglycosylases (TGTs). These enzymes incorporate guanine substituents into tRNA Asp , tRNA Asn tRNA His , and tRNA Tyr in all kingdoms of life. In contrast to the homodimeric bacterial TGT, the active eukaryotic TGT is a heterodimer in solution, comprised of a catalytic QTRT1 subunit and a noncatalytic QTRT2 subunit. Bacterial TGT enzymes, that incorporate a queuine precursor, have been identified or proposed as virulence factors for infections by pathogens in humans and therefore are valuable targets for drug design. To date no structure of a eukaryotic catalytic subunit is reported, and differences to its bacterial counterpart have to be deducted from sequence analysis and models. Here we report the first crystal structure of a eukaryotic QTRT1 subunit and compare it to known structures of the bacterial TGT and murine QTRT2. Furthermore, we were able to determine the crystal structure of QTRT1 in complex with the queuine substrate.

Download RCSB-PDB Structures:

Pdb Files	6H42.pdb 6H45.pdb 7NQ4.pdb
Pdbx/mmCIF Files	6H42.cif 6H45.cif 7NQ4.cif

Protein sequence:

MAGAATQASLESAPRIMRLVAECSRSRARAGELWLPHGTVATPVFMPVGTQATMKGITTEQLDALGCRICLGNTYHLGLRPGPELIQKANGLHGFMNWPHNLLTDSGGFQMVSLVSLSEVTEEGVRFRSPYDGNETLLSPEKSVQIQNALGSDIIMQLDDVVSSTVTGPRVEEAMYRSIRWLDRCIAAHQRPDKQNLFAIIQGGLDADLRATCLEEMTKRDVPGFAIGGLSGGESKSQFWRMVALSTSRLPKDKPRYLMGVGYATDLVVCVALGCDMFDCVFPTRTARFGSALVPTGNLQLRKKVFEKDFGPIDPECTCPTCQKHSRAFLHALLHSDNTAALHHLTVHNIAYQLQLMSAVRTSIVEKRFPDFVRDFMGAMYGDPTLCPTWATDALASVGITLG

Comments:

tRNA-guanine transglycosylase is a heterodimeric enzyme complex that plays a critical role in tRNA modification by synthesizing the 7-deazaguanosine queuosine, which is found in tRNAs that code for asparagine, aspartic acid, histidine and tyrosine.

Alpha Fold Predicted Structure:

Clear Selection and Reset Camera

Protein sequence:

M A G A A T Q A S L E S A P R I M R L V A E C S R S R A R A G E L W L P H G T V A T P V F M P V G T Q A T M K G I T T E Q L D A L G C R I C L G N T Y H L G L R P G P E L I Q K A N G L H G F M N W P H N L L T D S G G F Q M V S L V S L S E V T E E G V R F R S P Y D G N E T L L S P E K S V Q I Q N A L G S D I I M Q L D D V V S S T V T G P R V E E A M Y R S I R W L D R C I A A H Q R P D K Q N L F A I I Q G G L D A D L R A T C L E E M T K R D V P G F A I G G L S G G E S K S Q F W R M V A L S T S R L P K D K P R Y L M G V G Y A T D L V V C V A L G C D M F D C V F P T R T A R F G S A L V P T G N L Q L R K K V F E K D F G P I D P E C T C P T C Q K H S R A F L H A L L H S D N T A A L H H L T V H N I A Y Q L Q L M S A V R T S I V E K R F P D F V R D F M G A M Y G D P T L C P T W A T D A L A S V G I T L G

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-Q9BXR0-F1.pdb
Alpha Fold Pdbx/mmCIF Files	AF-Q9BXR0-F1.cif
DSSP Secondary Structures	Q9BXR0.dssp

Publications:

Title	Authors	Journal	Details	PubMed Id	DOI
Characterization of the human tRNA-guanine transglycosylase: confirmation of the heterodimeric subunit structure.	Chen YC, Kelly VP, Stachura SV, Garcia GA	RNS	[details]	20354154	10.1261/rna.1997610