>TIGR00471 pheT_arch phenylalanyl-tRNA synthetase, beta subunit; InterPro: IPR004531 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 . Phenylalanyl-tRNA synthetase (6.1.1.20 from EC) is an alpha2/beta2 tetramer composed of 2 subunits that belongs to class IIc. In eubacteria, a small subunit (pheS gene) can be designated as beta (E. coli) or alpha subunit (see IPR002319 from INTERPRO). Reciprocally the large subunit (pheT gene) can be designated as alpha (E. coli) or beta. In all other kingdoms the two subunits have equivalent length in eukaryota, and can be identified by specific signatures. The enzyme from Thermus thermophilus has an alpha 2 beta 2 type quaternary structure and is one of the most complicated members of the synthetase family. Identification of phenylalanyl-tRNA synthetase as a member of class II aaRSs was based only on sequence alignment of the small alpha-subunit with other synthetases . This family describes the beta subunit. The beta subunits break into two subfamilies that are considerably different in sequence, length, and pattern of gaps (see also IPR004532 from INTERPRO). This family represents the subfamily that includes the beta subunit from eukaryotic cytosol, the archaea, and spirochetes.; GO: 0000166 nucleotide binding, 0004826 phenylalanine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006432 phenylalanyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=98.23 E-value=1.2e-05 Score=62.27 Aligned_cols=231 Identities=19% Similarity=0.310 Sum_probs=156.4 Q ss_pred HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCCCCCCCCCCCCC--HHHHHHHHHHHHHHHCCCEEECCCEE Q ss_conf 9999999999999999999998567666765431000001123212267423--89999999999998739876237234 Q gi|254780317|r 65 AILNQLKVDISGKISARKDFIRNQLIFEQISSQSVDVSLPVFSSPCHRGRIH--PVTQVIDEVTCIFMDMGFALEEGSDI 142 (366) Q Consensus 65 k~iNelK~~Ie~~i~~kk~~L~~~~~~~kl~~E~iDVTLP~~~~~~~~G~~H--PItqvi~eI~~IF~~lGF~v~eGPEI 142 (366) T Consensus 348 v~IP~YR~DIlHE~D~----~EdvAigyG~~--~~~pE~P---~~~t~g~~~Plp~~~~~~~~R~~mvG~GF~EVi~l~L 418 (605) T TIGR00471 348 VVIPAYRVDILHEVDV----IEDVAIGYGYN--NIEPELP---KILTIGRLKPLPLEKVSDIIREIMVGLGFQEVISLTL 418 (605) T ss_pred ECCCCCCCCHHHHHHH----HHHHHHHHHHH--CCCCCCC---CHHHHHCCCCCCHHHHHHHHHHHHHCCCHHHHHHCCC T ss_conf 7178976402100317----77778873221--0687777---1222210488877788757654220470434241004 Q ss_pred ECHHHHHHHHCCCCCCCCCCCCCEEEEE--CCCCCCCCCCCCCCCCHHHHHHH---HCCCEEEEEECCCCCCCCCC---- Q ss_conf 1588988861898877331633127750--56665563224467630555543---03631225410576474544---- Q gi|254780317|r 143 ETDYYNFAALNFPDDHPARQMHDTFFVP--GIAGGKHKLLRTHTSPVQIRVME---SQDLPIKVIVPGKTYRRDSD---- 213 (366) Q Consensus 143 Etd~~NFdaLNiP~~HPARdmqDTFyl~--~~~~~~~~lLRthTS~vQiR~m~---~~~pP~~~~~~GrvyR~d~D---- 213 (366) T Consensus 419 ~s~~~~~~~mR~~d~~------~k~~v~V~~P~t~e~~~~R~SlLP~LLe~~~~Nk~~~lP~KiFE~GDVV~~d~~~erk 492 (605) T TIGR00471 419 TSEEVLFKRMRIEDNN------FKLAVKVANPLTLEYTIVRTSLLPGLLETLSENKHHELPQKIFEIGDVVVKDDDSERK 492 (605) T ss_pred CCHHHHHHHHCCCCCC------CHHHHHHCCCCCCCHHHHHHHHHHHHHHHHHHHCCCCCCCEEEEEEEEEEECCCHHHH T ss_conf 7806999980757887------2003331178762333776562236788886514899882078874388828720122 Q ss_pred CCCCCCCCCCCEEEECCC----------CCHHHHHHHHHHHHHHHCCCCCCEEEEEEC-CCCCCCCC--CEEEEEEECCC Q ss_conf 213781002005786178----------668999889999999970888662645423-88985266--10367875058 Q gi|254780317|r 214 STHSPMFHQIEGLVVSDS----------ATIANLRWVLESFCKSFFEVSSLQMRFRPS-FFPFTEPS--FEVDVRCSFSD 280 (366) Q Consensus 214 ~tH~~~FhQ~egl~v~~~----------i~~~~lk~~l~~~~~~~fg~~~~~~r~rp~-~fPftePs--~Evdv~~~~~~ 280 (366) T Consensus 493 ~~~~r~~~~lA~~~~~~~eiiqGllGki~~F~eI~S~v~~~~~~L-~---~e~~~~e~D~~~~fi~GR~A~I~~~----- 563 (605) T TIGR00471 493 ETRSRVVTKLAVLITHSEEIIQGLLGKIANFNEIKSIVAALLREL-G---IEYEIEESDEHPSFIEGRGAKIVIE----- 563 (605) T ss_pred HHCCEEEEEEEEEEECCHHHHHHHHHHHCCCHHHHHHHHHHHHHC-C---CCEEEECCCCCCCCCCCCEEEEEEC----- T ss_conf 305625556787762761433435532013024788999999963-9---8379831788613116710489841----- Q ss_pred CEEEECCCCCEEEEE-CCCCCCHHHHHHCCCCCCCEEEEEEECCHHH Q ss_conf 804224688348984-5756388899856988000379963134469 Q gi|254780317|r 281 GIIKFDEGTEWMEIL-GCGMVDPRVLRGVGIDPDIYQGFAWGMGLDR 326 (366) Q Consensus 281 ~~~~~~~~~~WiEi~-g~Gm~~p~vl~~~g~d~~~~~g~AfG~G~eR 326 (366) T Consensus 564 GK----~GaeP~~IGG~FGe~HPEV~~NF~l~---~Pvs~fE~~~~~ 603 (605) T TIGR00471 564 GK----EGAEPKAIGGVFGEIHPEVLTNFELE---FPVSAFEVNIEV 603 (605) T ss_pred CC----CCCCCCCCCCCCCCEECCEECCCCCC---EEEEEEEEEEHH T ss_conf 65----78883325740231422056278832---016999985012

HHsearch alignment for GI: 254780317 and conserved domain: TIGR00471