SMART: Pfam domain B3

The domain within your query sequence starts at position 1 and ends at position 54; the E-value for the B3_4 domain shown below is 1.1e-9.

XENYPCLVDAEGDVISFPPITNSEKTKIKKTTCNLFLEVTSATSLQLCKDIMDS

B3_4

PFAM accession number:	PF03483
Interpro abstract (IPR005146):	This entry represents the B3/B4 domain found in tRNA synthetase beta subunits as well as in some non-tRNA synthetase proteins. This domain has a 3-layer structure, and contains a beta-sandwich fold of unusual topology, and contains a putative tRNA-binding structural motif [ (PUBMED:7664121) ]. In Thermus thermophilus, both the catalytic alpha- and the non-catalytic beta-subunits comprise the characteristic fold of the class II active-site domains. The presence of an RNA-binding domain, similar to that of the U1A spliceosomal protein, in the beta-subunit of tRNA synthetase indicates structural relationships among different families of RNA-binding proteins. Aminoacyl-tRNA synthetases can catalyse editing reactions to correct errors produced during amino acid activation and tRNA esterification, in order to prevent the attachment of incorrect amino acids to tRNA. The B3/B4 domain of the beta subunit contains an editing site, which lies close to the active site on the alpha subunit [ (PUBMED:15526031) ]. Disruption of this site abolished tRNA editing, a process that is essential for faithful translation of the genetic code.
GO function:	phenylalanine-tRNA ligase activity (GO:0004826), RNA binding (GO:0003723)

PFAM accession number:

PF03483

Interpro abstract (IPR005146):

This entry represents the B3/B4 domain found in tRNA synthetase beta subunits as well as in some non-tRNA synthetase proteins. This domain has a 3-layer structure, and contains a beta-sandwich fold of unusual topology, and contains a putative tRNA-binding structural motif [ (PUBMED:7664121) ]. In Thermus thermophilus, both the catalytic alpha- and the non-catalytic beta-subunits comprise the characteristic fold of the class II active-site domains. The presence of an RNA-binding domain, similar to that of the U1A spliceosomal protein, in the beta-subunit of tRNA synthetase indicates structural relationships among different families of RNA-binding proteins.

Aminoacyl-tRNA synthetases can catalyse editing reactions to correct errors produced during amino acid activation and tRNA esterification, in order to prevent the attachment of incorrect amino acids to tRNA. The B3/B4 domain of the beta subunit contains an editing site, which lies close to the active site on the alpha subunit [ (PUBMED:15526031) ]. Disruption of this site abolished tRNA editing, a process that is essential for faithful translation of the genetic code.

GO function:

phenylalanine-tRNA ligase activity (GO:0004826), RNA binding (GO:0003723)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry B3_4