>TIGR00396 leuS_bact leucyl-tRNA synthetase; InterPro: IPR002302 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 . Leucyl tRNA synthetase (6.1.1.4 from EC) is an alpha monomer that belongs to class Ia. There are two different families of leucyl-tRNA synthetases. This family includes the eubacterial and mitochondrial synthetases. The crystal structure of leucyl-tRNA synthetase from the hyperthermophile Thermus thermophilus has an overall architecture that is similar to that of isoleucyl-tRNA synthetase, except that the putative editing domain is inserted at a different position in the primary structure. This feature is unique to prokaryote-like leucyl-tRNA synthetases, as is the presence of a novel additional flexibly inserted domain . ; GO: 0000166 nucleotide binding, 0004823 leucine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006429 leucyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=96.47  E-value=0.0075  Score=39.68  Aligned_cols=93  Identities=23%  Similarity=0.312  Sum_probs=67.8

Q ss_pred             CCCCCC-CCHHHHHHHHHHHHHHHHC--CCEEEEE---------------EC-CCCCCCCCHHHHHHHHHHHHHCCCCCC
Q ss_conf             433887-8501599999999999971--8849999---------------70-486663886799999999886589888
Q gi|255764513|r   13 PSPTGE-PHIGTAYTALFNYLIAKRT--GGKFILR---------------IE-DTDSKRSTLESENAVMQSLKWCGLNWD   73 (492)
Q Consensus        13 PsPtG~-lH~G~~rtal~n~l~a~~~--~g~f~lR---------------ie-Dtd~~R~~~~~~~~i~~~l~wlgl~~D   73 (492)
T Consensus        40 PYPSG~GLH~GHvR~YTItDvl~Ry~r~~GynVLHP~GwDAFGLPAEnaAI~~~~~P~~WT~~NI~~m~~Ql~~LGf~yD  119 (916)
T TIGR00396        40 PYPSGAGLHMGHVRNYTITDVLSRYKRMKGYNVLHPMGWDAFGLPAENAAIKRGIHPAKWTYENIANMKKQLQALGFSYD  119 (916)
T ss_pred             CCCCCCCCCCCCCCHHHHHHHHHHHHHHCCCCCCCCCCCCCCCCCHHHHHHHCCCCCHHHHHHHHHHHHHHHHHHCCCCC
T ss_conf             79560775016514235764999999862883247667574564258999864898700378999999999998455644


Q ss_pred             CCCCCCCCCCCEECCCCHHHHHHHHHHHHHCCCEEEC
Q ss_conf             6765588767632326289999999999988982451
Q gi|255764513|r   74 EGPDIGGAYGPYRQSERKNIYQPYVQNLLEKKLAFRC  110 (492)
Q Consensus        74 e~~~~~g~~~p~~QS~r~~~y~~~~~~L~~~g~aY~c  110 (492)
T Consensus       120 w~RE~~T~~P~YYk-----wtQWiF~~Lf~kGLaY~k  151 (916)
T TIGR00396       120 WDREIATCDPEYYK-----WTQWIFLELFEKGLAYVK  151 (916)
T ss_pred             HHCCCCCCCCCCCH-----HHHHHHHHHHHCCCEEEE
T ss_conf             11053238887433-----666888999762852763