>TIGR00463 gltX_arch glutamyl-tRNA synthetase; InterPro: IPR004526 The aminoacyl-tRNA synthetases (6.1.1. from EC) catalyse the attachment of an amino acid to its cognate transfer RNA molecule in a highly specific two-step reaction. These proteins differ widely in size and oligomeric state, and have limited sequence homology . The 20 aminoacyl-tRNA synthetases are divided into two classes, I and II. Class I aminoacyl-tRNA synthetases contain a characteristic Rossman fold catalytic domain and are mostly monomeric . Class II aminoacyl-tRNA synthetases share an anti-parallel beta-sheet fold flanked by alpha-helices , and are mostly dimeric or multimeric, containing at least three conserved regions , , . However, tRNA binding involves an alpha-helical structure that is conserved between class I and class II synthetases. In reactions catalysed by the class I aminoacyl-tRNA synthetases, the aminoacyl group is coupled to the 2'-hydroxyl of the tRNA, while, in class II reactions, the 3'-hydroxyl site is preferred. The synthetases specific for arginine, cysteine, glutamic acid, glutamine, isoleucine, leucine, methionine, tyrosine, tryptophan and valine belong to class I synthetases; these synthetases are further divided into three subclasses, a, b and c, according to sequence homology. The synthetases specific for alanine, asparagine, aspartic acid, glycine, histidine, lysine, phenylalanine, proline, serine, and threonine belong to class-II synthetases . Glutamyl-tRNA synthetase (6.1.1.17 from EC) is a class Ic synthetase and shows several similarities with glutaminyl-tRNA synthetase concerning structure and catalytic properties. It is an alpha2 dimer. To date one crystal structure of a glutamyl-tRNA synthetase (Thermus thermophilus) has been solved. The molecule has the form of a bent cylinder and consists of four domains. The N-terminal half (domains 1 and 2) contains the 'Rossman fold' typical for class I synthetases and resembles the corresponding part of E. coli GlnRS, whereas the C-terminal half exhibits a GluRS-specific structure . ; GO: 0000166 nucleotide binding, 0004818 glutamate-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006424 glutamyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=93.70  E-value=0.13  Score=30.85  Aligned_cols=72  Identities=19%  Similarity=0.159  Sum_probs=43.4

Q ss_pred             ECCCCCCCHHHHHHHHHHHHHHHHHCCCCEEEEEEEHHHHCCCCCHHHHHHHHHHHHH-HHHHCCCCCCCCEEEECCCHH
Q ss_conf             1589678105579889999999850599589997311573078985899999999999-999628681112365247407
Q gi|254780794|r   12 VQPTGVLHLGNYLGMIRNVIRRQETCNHLGMYFIADLHAITNNIVQENLRYQSRLFVA-SFLAAGVDPSRNIIFKQSDVG   90 (355)
Q Consensus        12 ~~PtG~~HLG~y~g~i~~~i~lq~~~~~~~~~~IAD~halt~~~~~~~~~~~~~~~~~-~~lA~Gldp~k~~if~QS~v~   90 (355)
T Consensus       108 PnPsGpLhiGhArAa~lN~-~fa~~Y~GklIlR~dD----TdP~tk-r~~~Eayd~i~eDLdwLG~k~Dev~--y~Sdr~  179 (600)
T TIGR00463       108 PNPSGPLHIGHARAAILNQ-YFAKKYEGKLILRFDD----TDPRTK-RVKPEAYDMILEDLDWLGVKGDEVV--YQSDRI  179 (600)
T ss_pred             CCCCCCCCHHHHHHHHHHH-HHHHHCCCCEEEEEEC----CCCCCC-CCCHHHHHHHHHHHHHCCCCEEEEE--EEECCH
T ss_conf             5454587523354223204-6685418817999755----878878-8872466524877875284200689--830530


Q ss_pred             H
Q ss_conf             8
Q gi|254780794|r   91 Y   91 (355)
Q Consensus        91 e   91 (355)
T Consensus       180 ~  180 (600)
T TIGR00463       180 E  180 (600)
T ss_pred             H
T ss_conf             1