|PROSITE documentation PDOC51709|
The P-loop (see <PDOC00017>) guanosine triphosphatases (GTPases) control a multitude of biological processes, ranging from cell division, cell cycling, and signal transduction, to ribosome assembly and protein synthesis. GTPases exert their control by interchanging between an inactive GDP-bound state and an active GTP-bound state, thereby acting as molecular switches. The common denominator of GTPases is the highly conserved guanine nucleotide-binding (G) domain that is responsible for binding and hydrolysis of guanine nucleotides.
TrmE (also called MnmE) contains a canonical G domain and is conserved in all three kingdoms of life. It is involved in the modification of uridine bases (U34) at the first anticodon (wobble) position of tRNAs decoding two-family box triplets. TrmE is organized as a multidomain protein consisting of an ~220-amino acid N-terminal domain, probably required for self-assembly, a middle GTPase domain, of about 160 residues, and an ~75-amino acid C-terminal domain, which contains a highly conserved CxGK motif. TrmE contains at least four of the five conserved nucleotide-binding motifs G1 (GxxxxGK[ST] or P-loop), G2 (T), G3 (DxxG) and G4 ([NT]KxD). The totally invariant alanine in the SA[KL] (G5) motif of Ras anGalph proteins is less well conserved [1,2,3,4,5].
The profile we developed covers the entire TmrE-type G domain.Last update:
March 2014 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Leipe D.D. Wolf Y.I. Koonin E.V. Aravind L.|
|Title||Classification and evolution of P-loop GTPases and related ATPases.|
|Source||J. Mol. Biol. 317:41-72(2002).|
|2||Authors||Yamanaka K. Hwang J. Inouye M.|
|Title||Characterization of GTPase activity of TrmE, a member of a novel GTPase superfamily, from Thermotoga maritima.|
|Source||J. Bacteriol. 182:7078-7082(2000).|
|3||Authors||Yim L. Martinez-Vicente M. Villarroya M. Aguado C. Knecht E. Armengod M.-E.|
|Title||The GTPase activity and C-terminal cysteine of the Escherichia coli MnmE protein are essential for its tRNA modifying function.|
|Source||J. Biol. Chem. 278:28378-28387(2003).|
|4||Authors||Scrima A. Vetter I.R. Armengod M.E. Wittinghofer A.|
|Title||The structure of the TrmE GTP-binding protein and its implications for tRNA modification.|
|Source||EMBO J. 24:23-33(2005).|
|5||Authors||Monleon D. Martinez-Vicente M. Esteve V. Yim L. Prado S. Armengod M.-E. Celda B.|
|Title||Structural insights into the GTPase domain of Escherichia coli MnmE protein.|