>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=98.60 E-value=1.8e-07 Score=71.32 Aligned_cols=174 Identities=13% Similarity=0.269 Sum_probs=96.2 Q ss_pred CCCCCCCHH----HHHHHHHHHHHHHCC--C----CCCCEEEECCHHHCC-------CCCCC------------------ Q ss_conf 336777613----689999999997226--6----345115311011012-------21100------------------ Q gi|254780285|r 353 IYVMGSDHS----GYVKRLEAVAAAVSE--K----KAQINVLLCELVRLY-------RDGMP------------------ 397 (586) Q Consensus 353 iyVv~~~Q~----~h~~~v~~~~~~lg~--~----~~~~~~~~~~~v~l~-------~dg~~------------------ 397 (586) T Consensus 566 ~YiGG~EHAiLHLLY~RF~hK~L~D~g~v~~PaGi~EPFkKL~~QGMVlg~~f~y~~~~g~~~W~~p~d~~~~~d~~~d~ 645 (916) T TIGR00396 566 LYIGGIEHAILHLLYARFFHKFLYDLGLVSTPAGIKEPFKKLINQGMVLGDAFYYKKPNGKRIWVVPADELIERDEKGDI 645 (916) T ss_pred EEECCHHHHHHHHHHHHHHHHHHHHCCCCCCCCCCCCHHHHHHHCCEEECCCEEECCCCCCEEEEECCCCEEECCCCCCC T ss_conf 10262689989988889999999745761587766571455420000211613413899736776457516610466786 Q ss_pred ----------------CCCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHCCHHHHHHHHHHHHHHCCCCHHHHHHHHHHHH Q ss_conf ----------------0001223302456777776321123455542000123334477765320244367888888889 Q gi|254780285|r 398 ----------------IKMSKRAGDFITLRHVVDEVGSDSVRFMMLWRKNSELLDFDFCKVKEQSKENPVFYVQYAYARC 461 (586) Q Consensus 398 ----------------~kmstR~G~~v~l~dll~evg~~aiky~~L~~~~~~~~~Fd~d~~l~~~~~nt~~YiqYa~aR~ 461 (586) T Consensus 646 ~~~~d~~~~~~~~~~~~KMSKSK~N~i~P~e~~~~yGADa~Rlf~mF~~P~~~-~L~W~~~g-~~G~~R--FL~----RV 717 (916) T TIGR00396 646 KKAKDKSGGELVVVGYEKMSKSKGNGIDPQEIVKKYGADALRLFIMFMGPIAA-SLEWNESG-LEGARR--FLD----RV 717 (916) T ss_pred CCCEECCCCCEEEEEEEEECCCCCCCCCCHHHHHHCCHHHHHHHHHHCCCHHH-CCCCCCCC-HHHHHH--HHH----HH T ss_conf 54232588824788777620236798870389740480279999970488314-14777111-013568--889----99 Q ss_pred HHHHHHHHHHCCCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHCCCHH--HHHHHHHHHHHHHHHHHH Q ss_conf 99987533200246832234223552114998999999998421899999998528127--999999999988999870 Q gi|254780285|r 462 RSIFRQAKDIFPDLDFDLFPRNVIPQESEFDTSELQLIVHLAEYPRVIENATIAQEPYK--LAFYLYDLASVFHGHWSH 538 (586) Q Consensus 462 ~SIlrKa~~~~~~~~~~~~~~~~~~~~~~~~~~E~~L~~~l~~f~~vi~~a~~~~~P~~--l~~Yl~~La~~Fn~fY~~ 538 (586) T Consensus 718 w~l~~~~~~~~~~~~~avrP~~~~~~-~~l~~~~~~~~~~~---~~~lk~v~e~~~~~~~~fNT~IS~~M~l~N~L~k~ 792 (916) T TIGR00396 718 WNLVKEILGELSGIISAVRPKTELTE-TALEEAQKELRREV---HKFLKKVTEDLEKLELSFNTAISAMMELLNALYKA 792 (916) T ss_pred HHHHHHHCCCHHHEEEEECCCCCCCC-CCCCCHHHHHHHHH---HHHHHHHHHHCCCCCHHHHHHHHHHHHHHHHHHHH T ss_conf 99998732660002554246100343-11230468999999---99998887531762013558999999999998731

HHsearch alignment for GI: 254780285 and conserved domain: TIGR00396