>TIGR00457 asnS asparaginyl-tRNA synthetase; InterPro: IPR004522 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 . AsparaginyltRNA synthetase (6.1.1.22 from EC) is an alpha2 dimer that belongs to class IIb. There is a striking similarity between asparaginyl-tRNA synthetases and archaeal/eukaryotic type aspartyl-tRNA synthetases (IPR004523 from INTERPRO) and a striking divergence of bacterial type aspartyl-tRNA synthetases (IPR004524 from INTERPRO). This family, AsnS, represents asparaginyl-tRNA synthetases from the three domains of life. Some species lack this enzyme and charge tRNA(asn) by misacylation with Asp, followed by transamidation of Asp to Asn.; GO: 0000166 nucleotide binding, 0004816 asparagine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006421 asparaginyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=92.79  E-value=0.042  Score=36.35  Aligned_cols=103  Identities=22%  Similarity=0.302  Sum_probs=66.6

Q ss_pred             CCCCHHHHHHH----HHHHHHHHCCCEEECCCEEECH--------H--HHHHHHCCCCCCCCCCCCCEEEEECCCCCCCC
Q ss_conf             74238999999----9999998739876237234158--------8--98886189887733163312775056665563
Q gi|254780317|r  113 GRIHPVTQVID----EVTCIFMDMGFALEEGSDIETD--------Y--YNFAALNFPDDHPARQMHDTFFVPGIAGGKHK  178 (366)
Q Consensus       113 G~~HPItqvi~----eI~~IF~~lGF~v~eGPEIEtd--------~--~NFdaLNiP~~HPARdmqDTFyl~~~~~~~~~  178 (366)
T Consensus       140 ~~~~AvmrvR~~l~~ai~~yF~~~gF~~V~~PilT~~d~EGAGElF~v~TLdl~~lp~~~g~~df~~~fFgk------~a  213 (495)
T TIGR00457       140 NTLGAVMRVRNALSQAIHEYFQKNGFVKVSPPILTSNDCEGAGELFKVSTLDLEKLPRNDGKIDFSKDFFGK------EA  213 (495)
T ss_pred             HHHHHHHHHHHHHHHHHHHHHHCCCCEEECCCEEECCCCCCCCCCCEEEEHHHHCCCCCCCCCCCCCCCCCC------EE
T ss_conf             887789999999999999876047867868863113688887543322003242153326888763024886------01


Q ss_pred             CCCCCCCCHHHHHHHHCCC-EEEEEECCCCCCCCC--CCCCCCCCCCCCE
Q ss_conf             2244676305555430363-122541057647454--4213781002005
Q gi|254780317|r  179 LLRTHTSPVQIRVMESQDL-PIKVIVPGKTYRRDS--DSTHSPMFHQIEG  225 (366)
Q Consensus       179 lLRthTS~vQiR~m~~~~p-P~~~~~~GrvyR~d~--D~tH~~~FhQ~eg  225 (366)
T Consensus       214 yL---TVSGQL~-~E~~A~AL~kvyTfGPTFRAEkS~T~RHLsEFWMiEP  259 (495)
T TIGR00457       214 YL---TVSGQLY-AEAYALALSKVYTFGPTFRAEKSNTSRHLSEFWMIEP  259 (495)
T ss_pred             EE---EECCHHH-HHHHHHHHCCCEECCCCEECCCCCCCCCHHHHHHHHH
T ss_conf             23---3022789-9999997478144587400428648701112210112