HHsearch alignment for GI: 254781118 and conserved domain: TIGR00418
>TIGR00418 thrS threonyl-tRNA synthetase; InterPro: IPR002320 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 . Threonyl-tRNA synthetase (6.1.1.3 from EC) exists as a monomer and belongs to class IIa. The enzyme from Escherichia coli represses the translation of its own mRNA. The crystal structure of the complex between tRNA(Thr) and ThrRS show structural features that reveal novel strategies for providing specificity in tRNA selection. These include an amino-terminal domain containing a novel protein fold that makes minor groove contacts with the tRNA acceptor stem. The enzyme induces a large deformation of the anticodon loop, resulting in an interaction between two adjacent anticodon bases, which accounts for their prominent role in tRNA identity and translational regulation. A zinc ion found in the active site is implicated in amino acid recognition/discrimination . The zinc ion may act to ensure that only amino acids that possess a hydroxyl group attached to the beta-position are activated .; GO: 0004829 threonine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006435 threonyl-tRNA aminoacylation, 0005737 cytoplasm.
Probab=97.36 E-value=0.00032 Score=46.42 Aligned_cols=257 Identities=18% Similarity=0.184 Sum_probs=132.4
Q ss_pred CCCHHHHHHHHHHHHHHHHCCCCCCCCCCCCCCCHHHHHHHHCCC--------CCC-CCCCCEEEEEEEECCCCCCCC-E
Q ss_conf 168799999999999999838887888767888599999865155--------556-435988999868811148772-1
Q gi|254781118|r 9 SLSSNSIEVRSQKLNMLRKSLAEVYPAHFHRDITNAEVREKYSHL--------QND-EKSQDMITVAGRVYSSRNSGM-F 78 (502)
Q Consensus 9 ~~~~~~~~~R~~kl~~l~~~~~~pyP~~f~~t~~~~e~~~~~~~l--------~~~-~~~~~~V~i~Grv~~~R~~G~-F 78 (502)
T Consensus 40 ~~~~~dl~~ie~~m~~~~~~~-~~~~---~~~~s~~~A~~~f~~~~~~~k~~l~~~~~~~~~~~~~y~~~-------~~f 108 (595)
T TIGR00418 40 SITEEDLEKIEKEMKEIIKKN-YPIA---RLSVSLEEALEAFKEVGEPLKLELLDEIIPNGEAVTVYGQG-------EAF 108 (595)
T ss_pred HCCHHHHHHHHHHHHHHHHHH-CCEE---EEEECHHHHHHHHHHHCCHHHHHHHHHCCCCCCCEEEECCC-------CEE
T ss_conf 027789999999999998640-5702---57724789999998621312267785104566642042252-------134
Q ss_pred EEEECCCCEEE-EEEEC-----CCCCHHHHHHHHHCCCCEEEEEEE----EEECCCCCCCCCCCCEEEEECCCCCCCCCC
Q ss_conf 89977993599-99805-----427967888874237431689965----763056655342122012211355543222
Q gi|254781118|r 79 MDIHDASGKIQ-IFTHK-----DTADQDSQNLLSMIDIGDIIGITG----QVRRTKRGELTVNAQKIIMLSKALNSIPET 148 (502)
Q Consensus 79 i~LrD~~g~iQ-v~~~~-----~~~~~~~~~~~~~l~~gd~i~v~G----~v~~~~~gelei~~~~~~~l~~~~~~lP~~ 148 (502)
T Consensus 109 ~dlC~GpHlp~~~~~~~~~~~fkL~~~~gaYw~Gd~~n~~LqRiyGn~~~~~~~~k~~----L~~yl~~~eEa~~r~PD- 183 (595)
T TIGR00418 109 VDLCRGPHLPNTSRIKPAQKAFKLEKVAGAYWRGDSKNEMLQRIYGNIDITAFADKKQ----LAEYLKRLEEAKKREPD- 183 (595)
T ss_pred EECCCCCCCCCCCCCCCCCHHHHHHHHHHHHHCCCCCCCEEEEECCCEEEECCCCHHH----HHHHHHHHHHHHCCCCC-
T ss_conf 5615797683235667640345665432331026889853788857254501458789----99999999997426857-
Q ss_pred CCCC-CHHHHHH-H-------CCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCCCCCCCCCCEEEEEC
Q ss_conf 1253-1144542-0-------11001234444433578899999999873855345431156532356665542036412
Q gi|254781118|r 149 YYGL-SDVEIRY-R-------KRYLDIISNSDSKIRFQQRSLLISQIRHFMEKKGFMEVETPILQPIYGGATADPFKTHH 219 (502)
Q Consensus 149 ~~~~-~d~e~rl-~-------~R~LDl~~~~~~~~~l~~Rs~i~~~iR~~l~~~gF~EveTP~L~~~~~g~~~~~F~~~~ 219 (502)
T Consensus 184 HRklGKeL~Lf~f~~~~gpG~~~Wl-----PkG~---~ir~~ledf~~~~~~~~Gy~~V~TP~m~~~~l~~----~sGH~ 251 (595)
T TIGR00418 184 HRKLGKELELFSFEPEIGPGLPFWL-----PKGA---LIRNLLEDFVREKQIKRGYEEVETPIMYDSELWE----ISGHW 251 (595)
T ss_pred HHHHHHHHCCCCCCCCCCCCCEEEC-----CCHH---HHHHHHHHHHHHHHHHCCCCCCCCCEECCCCCHH----HHHHH
T ss_conf 2567545312345832048741465-----7646---7899999999999987588641574121565424----53054
Q ss_pred CCCCCCCC-CCHH--HHHHHHHHHCCCC--------------CHHHHHHH-HHHCCCCCCC----CCCCCCCCCCCCCCC
Q ss_conf 22225432-1001--2234444210243--------------02454345-3202542344----324521000100110
Q gi|254781118|r 220 NILKADMY-LRIA--PELYLKRVLISGL--------------TDQVFELN-RNFRNEGVSS----RHNPEFTMIEAYWAY 277 (502)
Q Consensus 220 ~~~~~~~y-L~qS--pql~~k~l~~~G~--------------~drvfeI~-~~FR~E~~~~----~H~pEFt~lE~e~a~ 277 (502)
T Consensus 252 ~~Y~e~Mf~~~~~~~~~~~LkPMnCpgH~~i~k~~~~SYR~LP~R~aE~g~~~hR~E~sG~L~GL~RvR~FT~dDaHi-f 330 (595)
T TIGR00418 252 DHYKERMFPFTEEDNQEFMLKPMNCPGHILIFKSSLRSYRDLPLRIAELGTTVHRYEKSGALHGLKRVRGFTQDDAHI-F 330 (595)
T ss_pred HHCCCCCCCCEEECCCCCCCCCCCCHHHHHHHCCCCCCHHHCCCHHHHCCCEEEEEECCCCCCHHHHHHHCCCCCCCE-E
T ss_conf 503423540101035303345677544533001777773233503433186047884254210101644306998524-5
Q ss_pred CC-HHHHHHHHHHHHHHH
Q ss_conf 00-111245678999988
Q gi|254781118|r 278 TD-YRDMMKLVEDLCHNL 294 (502)
Q Consensus 278 ~d-~~dim~l~E~li~~i 294 (502)
T Consensus 331 c~d~dQi~~E~~~~~~l~ 348 (595)
T TIGR00418 331 CTDEDQIKSEIKNQFRLI 348 (595)
T ss_pred ECCHHHHHHHHHHHHHHH
T ss_conf 378677999999999999