>TIGR00398 metG methionyl-tRNA synthetase; InterPro: IPR002304 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 . Methionyl-tRNA synthetase (6.1.1.10 from EC) is an alpha 2 dimer that belongs to class Ia. In some species (archaea, eubacteria and eukaryota) a coding sequence, similar to the C-term end of MetRS, is present as an independent gene which is a tRNA binding domain as a dimer. In eubacteria, MetRS can also be splitted in two sub-classes corresponding to the presence of one or two CXXC domain specific to zinc binding. The crystal structures of a number of methionyl-tRNA synthases are known , , .; GO: 0000166 nucleotide binding, 0004825 methionine-tRNA ligase activity, 0005524 ATP binding, 0006412 translation, 0006431 methionyl-tRNA aminoacylation, 0005737 cytoplasm.

Probab=97.74 E-value=0.0001 Score=52.28 Aligned_cols=282 Identities=19% Similarity=0.279 Sum_probs=156.9 Q ss_pred CCCCCCCCHHHHH-HHHHHHHHHHH--CCCEEEE----------------EECCCC-CCCCCHHHHHHHHHHHHHCCCCC Q ss_conf 4338878501599-99999999997--1884999----------------970486-66388679999999988658988 Q gi|255764513|r 13 PSPTGEPHIGTAY-TALFNYLIAKR--TGGKFIL----------------RIEDTD-SKRSTLESENAVMQSLKWCGLNW 72 (492) Q Consensus 13 PsPtG~lH~G~~r-tal~n~l~a~~--~~g~f~l----------------RieDtd-~~R~~~~~~~~i~~~l~wlgl~~ 72 (492) T Consensus 8 ~Y~Ng~pHlGH~~st~~~AD~~~RY~~~~G~~v~f~cGTDEHG~kI~~~A~~~g~tqP~~~vd~~~~~f~~~~~~lnI~f 87 (573) T TIGR00398 8 PYANGKPHLGHAYSTTILADVYARYKRLRGYEVLFVCGTDEHGTKIELKAEQEGLTQPKELVDKYHEEFKKLWKWLNISF 87 (573) T ss_pred CCCCCCHHHHHHHHHHHHHHHHHHHHHCCCCEEEEEECCCCCCCHHHHHHHHCCCCCHHHHHHHHHHHHHHHHHHHCCCC T ss_conf 66787112103667778999999998528974789851344687888869870899648999999999999998728456 Q ss_pred CCCCCCCCCCCCEECCCCHHHHHHHHHHHHHCCCEEE-------CCCCHHHHHHHHHHH--HHHHCCCC------CCCCC Q ss_conf 8676558876763232628999999999998898245-------148899977668876--64310002------36655 Q gi|255764513|r 73 DEGPDIGGAYGPYRQSERKNIYQPYVQNLLEKKLAFR-------CFCSTERLEEMRRAQ--RKRNIPSR------YDGHC 137 (492) Q Consensus 73 De~~~~~g~~~p~~QS~r~~~y~~~~~~L~~~g~aY~-------c~~t~eel~~~r~~~--~~~~~~~~------Y~~~~ 137 (492) T Consensus 88 D~-------F~RTTd~~H~~~v~~~f~~L~~nGyIY~~~~~g~YC~~c~~Fl~d-r~~~~~yv~g~CP~c~~~~~~gd~c 159 (573) T TIGR00398 88 DR-------FIRTTDEEHKEIVQKIFQKLLENGYIYEKEIKGLYCPECESFLPD-RKLVDDYVEGTCPKCGSEDARGDHC 159 (573) T ss_pred CC-------CCCCCCHHHHHHHHHHHHHHHHCCCCCHHCCCCCCCCCCCCCCCH-HHHHCCCCCCCCCCCCCCCCCCCCC T ss_conf 76-------546768888999999999987537741100353234756653622-3200133467488688777778775 Q ss_pred ----CCCCHHHHHH--HHHCCCCCEEE------EEECCCCEEECCCCCCC------------C---EECCCCCCCCCCEE Q ss_conf ----5788333001--12025774078------86224311430475134------------0---21364323564100 Q gi|255764513|r 138 ----LKLSSQEIER--LSQEQKKHVVR------LTVPNQGSCVFQDKVYG------------E---MEIPWNAVDMQVLL 190 (492) Q Consensus 138 ----r~l~~~e~~~--~~~~g~~~~iR------~k~p~~~~~~~~D~i~G------------~---~~~~~~~~~D~vi~ 190 (492) T Consensus 160 ~~Cg~~leP~~Li~P~c~~~~~~~~~~~~~hyFf~L~~~~-~~l~~~~~~~~~~~~~~~~~~n~~~~~~~~~GL~D~~It 238 (573) T TIGR00398 160 EVCGRHLEPFELINPRCVICKNKPELRDSEHYFFRLSAFE-KELEEWIKKNPESKSPASNVKNVAKQNWIKGGLKDLAIT 238 (573) T ss_pred CCCCCCCCCCHHCCCCEEEECCEEEEECCCCCCCCCHHHH-HHHHHHHHCCCCCCCHHHHHHHHHHHHHHCCCCCCCEEE T ss_conf 5465536850011870255488002513545223536888-999998614884242189999998899850687430110 Q ss_pred CCC-----CCH-----------------HHHHHHHH------------------HH-HHHHHHHHHCCCCCCCHHHHHHH Q ss_conf 045-----324-----------------89867887------------------64-44444431122354302478899 Q gi|255764513|r 191 KSD-----GMP-----------------TYHLANVI------------------DD-HLMKITHVARGEEWISSVPKHIL 229 (492) Q Consensus 191 r~d-----g~p-----------------tY~~a~vv------------------DD-~~m~ithviRg~d~~~~t~~q~~ 229 (492) T Consensus 239 R~~~~lkWG~pvP~~~~p~~~~YVW~DAl~gYiss~~~~~~~~~~~~~~~~~W~~~~~~~~~~HfI-GKD---I~~FH~i 314 (573) T TIGR00398 239 RDLVDLKWGIPVPNDGAPNKVVYVWFDALIGYISSLKALGIEKGLTEDWKKWWNNNSEDAELIHFI-GKD---IVRFHTI 314 (573) T ss_pred CCCCCCCCCCCCCCCCCCCCEEEEEECHHHHHHHHHHHCCCCCCCCHHHHHHCCCCCCCCEEEEEE-CCC---CCCHHHH T ss_conf 364412115317898987967998720345699997521335687578998626888650278884-241---2020333 Q ss_pred HH----HHHH--HCCCH--HHHHHHHHHHHCCCCCCCCCC-CCHHH-HHHCCCCHHHHHHHHHHCCCCCCCCCHHHCCHH Q ss_conf 99----9851--00000--101455531101322122343-30245-666297737799899850676665530110146 Q gi|255764513|r 230 LY----QYFN--FPIPE--FIHLPLIKNPDKSKLSKRRNP-TSISY-YSAMGYLPEALINFLALLFVHKSEDDDELMDMQ 299 (492) Q Consensus 230 l~----~al~--~~~p~--f~H~pli~~~~g~klSKR~~~-~~i~~-~~~~GylPeAilNyLalLGws~~~~d~Eifsl~ 299 (492) T Consensus 315 yWPa~L~~~~eN~~lP~q~~~hGyl--~~eG~KMSKS~G~vv~~~~~~~~~~~g~D~lRYYl~~~--~-~~~~D~~F~~~ 389 (573) T TIGR00398 315 YWPAMLMGLGENLPLPTQVFAHGYL--TVEGQKMSKSLGNVVDPEDDLLARGYGADILRYYLLKE--V-PLGKDGDFSWE 389 (573) T ss_pred HHHHHHHHCCCHHHHHHHHEEEEEE--EECCEEECCCCCCEECHHHHHHHCCCCHHHHHHHHHHH--C-CCCCCCCCCHH T ss_conf 4458885112100212132430168--84784432324753232178764478805788899864--2-43447656889 Q ss_pred HHHHHHHHHHCCC Q ss_conf 7776520211375 Q gi|255764513|r 300 QLIHHFDLHHLSK 312 (492) Q Consensus 300 eli~~FdL~~I~K 312 (492) T Consensus 390 ~f~~r~N~~L~n~ 402 (573) T TIGR00398 390 DFVERVNADLAND 402 (573) T ss_pred HHHHHHHHHHHHH T ss_conf 9999976887765

HHsearch alignment for GI: 255764513 and conserved domain: TIGR00398