>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=99.07  E-value=2.2e-10  Score=94.53  Aligned_cols=123  Identities=16%  Similarity=0.132  Sum_probs=87.7

Q ss_pred             CCEEEEEEEC--CCCCCC-CCCCCCHHHHHHHHHHHHHHHHCCCCCEEEEECCCCCCHHHHHHHHHCCCCCCCCCCHHHH
Q ss_conf             9847999616--788884-4411127999999999999970799845799605523388899998708986448848999
Q gi|254780573|r   23 PSNIRMYVCG--PTVYDF-AHIGNARPMIVFDVLYRLLRYYYGEKCVTYVRNITDIDDKIIERARQEHPSIPINDAISII   99 (461)
Q Consensus        23 ~~~v~~Y~CG--pTvy~~-~HiG~~r~~v~~D~l~R~L~~~~~~~~V~~v~niTDidDkii~~a~~~~~~~~~~~~~~~~   99 (461)
T Consensus        28 ~~~~K~YiL~MFPYPSG~GLH~GHvR~YTItDvl~Ry~r~~Gyn--VLHP~GwDAFGLPAEnaAI~~~~~------P~~W   99 (916)
T TIGR00396        28 SNKPKYYILSMFPYPSGAGLHMGHVRNYTITDVLSRYKRMKGYN--VLHPMGWDAFGLPAENAAIKRGIH------PAKW   99 (916)
T ss_pred             CCCCCEEEECCCCCCCCCCCCCCCCCHHHHHHHHHHHHHHCCCC--CCCCCCCCCCCCCHHHHHHHCCCC------CHHH
T ss_conf             55786466237879560775016514235764999999862883--247667574564258999864898------7003


Q ss_pred             HHHHHHHHHHHHHHHCCCCC-CHHHHHHHHHHHHHHH----HHHHHHCCCCCCCCCCEEEC
Q ss_conf             99999999998776268541-0001235677778999----99874114320128928752
Q gi|254780573|r  100 TSKNTQQFVKDTTRLACLAP-THQPRATNHIPQMIYL----IQNIILHGHAYEANNEIIFD  155 (461)
Q Consensus       100 a~~~~~~f~~d~~~L~v~~p-~~~pr~t~~i~~~i~~----i~~L~~~g~aY~~~g~VyFd  155 (461)
T Consensus       100 T~~NI~~m~~Ql~~LGf~yDw~RE~~T~~--P~YYkwtQWiF~~Lf~kGLaY~ke~~VNWC  158 (916)
T TIGR00396       100 TYENIANMKKQLQALGFSYDWDREIATCD--PEYYKWTQWIFLELFEKGLAYVKEATVNWC  158 (916)
T ss_pred             HHHHHHHHHHHHHHHCCCCCHHCCCCCCC--CCCCHHHHHHHHHHHHCCCEEEEEEEEEEC
T ss_conf             78999999999998455644110532388--874336668889997628527631113306