>TIGR02432 lysidine_TilS_N tRNA(Ile)-lysidine synthetase; InterPro: IPR012795 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 . The only examples in which the wobble position of a tRNA must discriminate between G and A of mRNA are AUA (Ile) vs. AUG (Met) and UGA (stop) vs. UGG (Trp). In all bacteria, the wobble position of the tRNA(Ile) recognizing AUA is lysidine, a lysine derivative of cytidine. This domain is found, apparently, in all bacteria in a single copy. Eukaryotic sequences appear to be organellar. The domain architecture of this protein is variable; some, including characterised proteins of Escherichia coli and Bacillus subtilis known to be tRNA(Ile)-lysidine synthetase, include a conserved 50-residue domain that many other members lack. This protein belongs to the ATP-binding PP-loop family. It appears in the literature and protein databases as TilS, YacA, and putative cell cycle protein MesJ (a misnomer).; GO: 0000166 nucleotide binding, 0005524 ATP binding, 0016879 ligase activity forming carbon-nitrogen bonds, 0008033 tRNA processing, 0005737 cytoplasm.

Probab=98.55  E-value=1.3e-06  Score=67.37  Aligned_cols=156  Identities=26%  Similarity=0.372  Sum_probs=104.1

Q ss_pred             CEEEEECCCCHHHHHHHHHHHH---CCCC-------EEEEEECCCCC--CCC-CHHHHHHHHHHCCCCCEEEEE-HHHHH
Q ss_conf             0366405640477999999862---2365-------69999738955--156-278999988623698579975-88999
Q gi|254780414|r  224 RVICAVSGGVDSTVAAFLIYEA---IGIN-------LTCVLVDHGFM--RKN-EVENIISLFKGYPNFPLRVVD-ASERF  289 (520)
Q Consensus       224 kVi~~lSGGVDStV~A~Ll~kA---ig~~-------l~~vfVD~Gll--Rkn-E~~~v~~~~~~~~~~~l~~vd-a~~~F  289 (520)
T Consensus         1 ~~lvAvSGG~DS~aLL~~L~~~~~~~~~~~~~~~~~~~a~h~nH~lR~~s~~~~~~~v~~~c~-~~~~~~~~~~~~~~~~   79 (204)
T TIGR02432         1 KILVAVSGGVDSMALLHLLLKLQPKLKISWQIKDFKLIAAHVNHGLRPESAQEEAEFVQQFCE-KLNIPLEIKKLVDVKA   79 (204)
T ss_pred             CEEEEEECCHHHHHHHHHHHHHHHHCCCCCCCCCEEEEEEEEECCCCHHHHHHHHHHHHHHHH-HCCCCEEEEEEECCCC
T ss_conf             978886286427999999999766327877887506899996177884158999999999999-6189569984212411


Q ss_pred             HHHHCCCCCHHHHHHHHHHHHHHHHHHHHHHCCC-CEEEEECCCCCHHHHHHCC--CCCCCCEEEEEECCCC---HHHH-
Q ss_conf             9996689888999988756589999999974399-7099864622024542024--6777630344302320---1132-
Q gi|254780414|r  290 IRKLKNIVDPETKRKVIGQLFIEVFEEEAKKIGG-AQFLGQGTLYPDVIESISF--FGGPSSIIKSHHNVGG---LPEH-  362 (520)
Q Consensus       290 l~~L~gv~DPE~KRkiIG~~Fi~vf~~~a~~~~~-~~~L~QGTlypDvIES~~~--~~~~~~~IKsHHNvgg---lp~~-  362 (520)
T Consensus        80 ~~-~~~~~~~E~~AR~~R---Y~~f~~~~~~~-~~~~~i~tAHh~dDq~ET~L~rL~RG~--~~~---Gl~g~~~~~~~~  149 (204)
T TIGR02432        80 LA-KGKKKNLEEAAREAR---YAFFEEIAKKH-GKADYILTAHHADDQAETILMRLLRGS--GLR---GLSGMPEIRPLG  149 (204)
T ss_pred             CC-CCCCCCHHHHHHHHH---HHHHHHHHHHC-CCCEEEEECCCCCCHHHHHHHHHHHCC--CCC---HHHHHCCCCCCC
T ss_conf             01-224767789999999---99999999972-994089972483227999999875168--700---011101336633


Q ss_pred             -----HCCCHHHHHHHHHHHHHHHHHHHHCCCH
Q ss_conf             -----0320223789873899999999819998
Q gi|254780414|r  363 -----MDMKLVEPLKELFKDEVRLLGKELRLPD  390 (520)
Q Consensus       363 -----~~~~liEPl~~l~KdEVR~lg~~Lglp~  390 (520)
T Consensus       150 ~~g~~~~~~~~RPLL~~~k~ei~~y~~~~~l~~  182 (204)
T TIGR02432       150 SLGWYKGGQIIRPLLNISKSEIEEYLKENGLPY  182 (204)
T ss_pred             CCCCCCCEEEEECCCCCCHHHHHHHHHHCCCCE
T ss_conf             244225632770775677899999999668965