>TIGR00399 metG_C_term methionyl-tRNA synthetase, beta subunit; InterPro: IPR004495 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 . The methionyl-tRNA synthetase (metG) (6.1.1.10 from EC) is a class I amino acyl-tRNA ligase. This family describes a region of the methionyl-tRNA synthetase that is present at the C-terminus of MetG in some species (Escherichia coli, Bacillus subtilis, Thermotoga maritima, Methanobacterium thermoautotrophicum), and as a separate beta chain in Aquifex aeolicus. It is absent in a number of other species (e.g. Mycoplasma genitalium, Mycobacterium tuberculosis), while Pyrococcus horikoshii has both a full length MetG and a second protein homologous to the beta chain only.; GO: 0000166 nucleotide binding, 0004825 methionine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006431 methionyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=98.70  E-value=1.4e-08  Score=80.17  Aligned_cols=95  Identities=22%  Similarity=0.298  Sum_probs=70.1

Q ss_pred             CEEEEEEEEEEECCCCC-CCEEEEECCCCCEEEEECCCCCCCCCCEE-EEECCCCEEC--CCCEEEEEEHH-CCCCCCCH
Q ss_conf             74899999975657998-70899975999579897548345589789-8966877925--89839833120-58650545
Q gi|254780316|r   43 PFTIVKVLSVERNPDLD-CAILRIDTGKHQEIQVVCGAPNVRVGLLG-VWAPPGSCIP--ENNMIVNVRKI-RGIESTGM  117 (805)
Q Consensus        43 ~vvvg~v~~~~~hP~ad-l~v~~Vd~g~~~~~~IvcgA~Nv~~g~~V-~~A~~Ga~lp--~g~~~i~~~~i-rGv~S~GM  117 (805)
T Consensus        47 dlRVg~i~~AE~v~kS~KLLkL~lDlG~~~~RQivSGI~----~~Y~~PEeLvGk~vivv~N---LKPaKl~~Gv~SeGM  119 (149)
T TIGR00399        47 DLRVGKILEAERVEKSDKLLKLKLDLGDEKDRQIVSGIA----EDYTDPEELVGKKVIVVAN---LKPAKLKFGVKSEGM  119 (149)
T ss_pred             EEEEEEEEEECCCCCCCCEEEEEEECCCCEECCEEEECH----HCCCCCHHHCCCEEEEEEC---CCCHHHCCCCCCCCC
T ss_conf             245577553205846566256887538970002352002----4178704743977999704---876012377343351


Q ss_pred             HHHHHHCCCCCCCCCEEEECC--CCCCCCCH
Q ss_conf             411887699854775078168--88888455
Q gi|254780316|r  118 MCSEKELMLSDDSASIMELPI--DAPVGGRL  146 (805)
Q Consensus       118 lCS~~ELgl~~~~~gI~~l~~--~~~~G~~~  146 (805)
T Consensus       120 iLAae~~g~nf--k~l~lls~~~~~~aG~ri  148 (149)
T TIGR00399       120 ILAAEDDGKNF--KNLFLLSPDKEVEAGERI  148 (149)
T ss_pred             EEEEECCCCCE--EEEEEECCCCCCCCCCCC
T ss_conf             78852699724--578886667888998435