>TIGR00459 aspS_bact aspartyl-tRNA synthetase; InterPro: IPR004524 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 . Aspartyl tRNA synthetase 6.1.1.12 from EC is an alpha2 dimer that belongs to class IIb. Structural analysis combined with mutagenesis and enzymology data on the yeast enzyme point to a tRNA binding process that starts by a recognition event between the tRNA anticodon loop and the synthetase anticodon binding module . This family represents aspartyl-tRNA synthetases from the bacteria and from mitochondria. In some species, this enzyme aminoacylates tRNA for both Asp and Asn; Asp-tRNA(asn) is subsequently transamidated to Asn-tRNA(asn). ; GO: 0000166 nucleotide binding, 0004815 aspartate-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006422 aspartyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=96.84  E-value=0.00058  Score=49.94  Aligned_cols=89  Identities=28%  Similarity=0.405  Sum_probs=37.6

Q ss_pred             HCCCCCCEEEEEECCCCCCCCCCEEEEEEECCCCEEEECCC----CCEEEEECCCC------CCHHHHH-HCCCCCCC--
Q ss_conf             70888662645423889852661036787505880422468----83489845756------3888998-56988000--
Q gi|254780317|r  248 FFEVSSLQMRFRPSFFPFTEPSFEVDVRCSFSDGIIKFDEG----TEWMEILGCGM------VDPRVLR-GVGIDPDI--  314 (366)
Q Consensus       248 ~fg~~~~~~r~rp~~fPftePs~Evdv~~~~~~~~~~~~~~----~~WiEi~g~Gm------~~p~vl~-~~g~d~~~--  314 (366)
T Consensus       496 ~fE~d~~E~~~~a~HHpFT~Pk~~~~~~lE~~p~~a~a~aYDlVlNG-~ElGGGSiRIh~~~~Q~~~F~d~Lgid~eea~  574 (653)
T TIGR00459       496 LFEKDEEEGRLVAAHHPFTMPKPEDLEDLETAPEEALAEAYDLVLNG-VELGGGSIRIHDPEVQEKVFEDILGIDPEEAR  574 (653)
T ss_pred             CCCCCCCCCCEEEECCCCCCCCCCCHHHHHCCHHHHHHHCCCEEEEE-EEECCCEEEECCHHHHHHHHHHHHCCCHHHHH
T ss_conf             56677652755840578898751227877407455412028768830-69887104642878999999876288989987


Q ss_pred             ----------------EEEEEEECCHHHHHHHHCCCCCHHH
Q ss_conf             ----------------3799631344699799738970587
Q gi|254780317|r  315 ----------------YQGFAWGMGLDRIAMLKYGMPDVRE  339 (366)
Q Consensus       315 ----------------~~g~AfG~G~eRlaml~~gi~diR~  339 (366)
T Consensus       575 EkFGFLLeA~~yGaPPHgG--~A~GlDRL~Mll~~~~nIRD  613 (653)
T TIGR00459       575 EKFGFLLEAFKYGAPPHGG--LALGLDRLVMLLTGTDNIRD  613 (653)
T ss_pred             HHHHHHHHHHHCCCCCCHH--HHHHHHHHHHHHCCCCCCCE
T ss_conf             7635687587357685101--55558999999808997220