HHsearch alignment for GI: 254780870 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=100.00 E-value=0 Score=742.09 Aligned_cols=407 Identities=21% Similarity=0.344 Sum_probs=375.2
Q ss_pred HHHHHHC-CCC--CCCCCCHHHHHHHCCCEECCCCCHHCCCCHHHHHHHHHHHHHHHHHHCCCEEEECCCCCCHHHHHHC
Q ss_conf 8887310-711--1412561221353032000388111043169999999999999998669889735751246898771
Q gi|254780870|r 7 FLPILQE-NPR--DAEIASHKLMLRTGMIHQHSKGIYSWLPLGQKALDNVNAIIREEQNRTGAIEMSVPTLQSADLWVES 83 (449)
Q Consensus 7 ~~~~l~~-~~~--d~~~~~~~ll~~~g~i~~~~~G~~~~lP~G~~i~~~le~~~r~~~~~~G~~ei~tP~l~~~eL~~~S 83 (449)
T Consensus 170 yl~~~eEa~~r~PDHRklGKeL~Lf~-f~~~~gpG~~~WlPkG~~ir~~ledf~~~~~~~~Gy~~V~TP~m~~~~l~~~s 248 (595)
T TIGR00418 170 YLKRLEEAKKREPDHRKLGKELELFS-FEPEIGPGLPFWLPKGALIRNLLEDFVREKQIKRGYEEVETPIMYDSELWEIS 248 (595)
T ss_pred HHHHHHHHHCCCCCHHHHHHHHCCCC-CCCCCCCCCEEECCCHHHHHHHHHHHHHHHHHHCCCCCCCCCEECCCCCHHHH
T ss_conf 99999997426857256754531234-58320487414657646789999999999998758864157412156542453
Q ss_pred CCCHHHHHHHCCHHHCCCCCCEECCCCCCCCCCCHHHCCCCCCCCCEEEEECC-CCCCCCCCCCC-CCCCCEEEEEEECC
Q ss_conf 97311222210402137862000345554310110000134201340264146-53345667675-43453166874042
Q gi|254780870|r 84 GRYDSYGKEMLRLADRNDKAMIYGPTHEEVMTDIFRSHIKSYRNLPFTFYQIQ-LKFRDELRPRF-GVMRSREFLMKDAY 161 (449)
Q Consensus 84 Gh~d~~~~em~~~~d~~~~~~~LrP~~~e~~~~i~~~~~~SYr~LPlr~y~ig-~~fR~E~rp~~-GL~R~ReF~q~D~~ 161 (449)
T Consensus 249 GH~~~Y~e~Mf~~~~~~~~~~~LkPMnCpgH~~i~k~~~~SYR~LP~R~aE~g~~~hR~E~sG~L~GL~RvR~FT~dDaH 328 (595)
T TIGR00418 249 GHWDHYKERMFPFTEEDNQEFMLKPMNCPGHILIFKSSLRSYRDLPLRIAELGTTVHRYEKSGALHGLKRVRGFTQDDAH 328 (595)
T ss_pred HHHHHCCCCCCCCEEECCCCCCCCCCCCHHHHHHHCCCCCCHHHCCCHHHHCCCEEEEEECCCCCCHHHHHHHCCCCCCC
T ss_conf 05450342354010103530334567754453300177777323350343318604788425421010164430699852
Q ss_pred EECCCHHHHHHHHHHHHHHHHHHHHHCCCHHHHHHHCCHHCCCCHHHHHHHHCCCCCC-EEEECCCCCCCCCCHHHCCHH
Q ss_conf 2118868879999999998741111006201223311001013113343454686770-143101003477641112201
Q gi|254780870|r 162 SFDLTPEGSKHSYNKMFVSYLRIFHRLGLKSIPMRAESGPIGGDLSHEFIVLADTGET-QVFCSKDFMDFPIPSENTDFD 240 (449)
Q Consensus 162 ~F~~~~e~~~~e~~~~~~~~~~i~~~lgl~~~~v~~~~~~ig~~~s~e~~~~~~~~e~-~~~~~~~~~~~~~~~~~~~~~ 240 (449)
T Consensus 329 ifc~d~dQi~~E~~~~~~l~~~v~~~fgf~~~~~~LS~R~P--------------e~~~Ky~g~d~~W~~~~~~l~~~l~ 394 (595)
T TIGR00418 329 IFCTDEDQIKSEIKNQFRLIQKVYSKFGFSNYKYELSTRDP--------------ENDKKYIGEDELWEKAESALEEALK 394 (595)
T ss_pred EEECCHHHHHHHHHHHHHHHHHHHHHHCCCCCEEEEEECCC--------------CCCCCCCCCHHHHHHHHHHHHHHHH
T ss_conf 45378677999999999999999887288421689987177--------------7545545887899999999999985
Q ss_pred HHHCCCCCCCCCCCCCCCCHHHCHHHHHCCCCCCCEEEEEEEECCCEEECCCCCCCCCEEEEECCC--CCC-CCCCCCCC
Q ss_conf 210011220001363212011000233035876552432111158144223112230115896477--772-32336663
Q gi|254780870|r 241 DIISLNSIVEQWTAPYAATSDVHNEKLFDSLPENKRVSARGIEVGHIFYFGTKYSLPMSATFKGAD--GKD-HYVQMGSY 317 (449)
Q Consensus 241 ~~~~~~~~~~~~~~~~~~~~d~~~~~~~d~l~~~~~~~~~~ie~~~~f~lG~~ys~~~~~~~~~~~--g~~-~~~~~g~~ 317 (449)
T Consensus 395 ~~~~~yei~~G~~AFYGPKiDf---~~~DaL~R~~q~~TvQlD----f~lPeRF----~l~Y~~~dqd~~~~~Pv~IHra 463 (595)
T TIGR00418 395 ELGVDYEIDEGEGAFYGPKIDF---QIKDALGREWQCATVQLD----FELPERF----DLTYINEDQDNKEKRPVMIHRA 463 (595)
T ss_pred CCCCCEEEECCCCEEECCEEEE---EEEECCCCHHHCCCEEEE----CCCCCCC----CCEEEEECCCCCCCCCEEEECC
T ss_conf 0798405507881130222688---875101764258814887----1588720----3148420367870067789804
Q ss_pred CCCCCCCHHHHHHCCCCCCC----CCCCHHHCCCCCEEEECCCCHHHHHHHHHHHHHHHHHCCCEEEEECCCCCHHHHHH
Q ss_conf 44743002332210232111----11363320321102421788799999999999999986987999758979708678
Q gi|254780870|r 318 GIGAMRVVAAVIESSHDGKG----IIWPDSVAPFKISLINIKAHDQVCRDACEKIYARLSKVGCDVFWDDMGEQIGSQFA 393 (449)
Q Consensus 318 giG~~R~~~alle~~~d~~g----~~wP~~iaP~~v~Iipi~~~~~~~~~~A~~i~~~Lr~~Gi~v~~D~r~~~iGkK~~ 393 (449)
T Consensus 464 ~~GS~ERfi~iL~E~~~G~fde~~PMLP~WLaP~QV~viPV~i--~~h~~yA~kv~~~L~~~giRv~~D~r~e~lgkKIR 541 (595)
T TIGR00418 464 ILGSIERFIAILLEKYAGAFDERLPMLPLWLAPVQVVVIPVSI--EKHLDYAKKVAEKLKKEGIRVDVDDRNERLGKKIR 541 (595)
T ss_pred CCHHHHHHHHHHHHHHHHHHHCCCCCCCEECCCEEEEEEECCH--HHHHHHHHHHHHHHHHCCCEEEECCCCCCHHHHHH
T ss_conf 4005899999999875222114689885421762389970577--88999999999999857977988388880133202
Q ss_pred HHHHCCCCEEEEECCCHHHC--CEEEEEECC---CCCEEEEEHHHHHHHHHHH
Q ss_conf 78748998899986240235--718999989---9978786199999999999
Q gi|254780870|r 394 VADLLGFPLQVIVGSKFVSD--SKVEIKHRL---TGIREDMSLEEVINYASHR 441 (449)
Q Consensus 394 ~Ad~~gip~~iiiG~~el~~--~~Vtir~r~---tg~q~~v~l~eli~~i~~~ 441 (449)
T Consensus 542 ~a~~~kiPy~~V~Gd~E~e~~K~~v~vR~~~t~k~~~~~~m~~~E~~~~~~~~ 594 (595)
T TIGR00418 542 EAQKQKIPYMLVVGDKEMEELKEAVNVRTRKTLKGQKLEKMSLDEFLEKVRKE 594 (595)
T ss_pred HHHCCCCCEEEEECCHHHHCCCCEEEECCHHHHCCCCEEEECHHHHHHHHHHC
T ss_conf 20132206799987302313896685224021046310143099999999733