>TIGR00484 EF-G translation elongation factor G; InterPro: IPR004540 Translation elongation factors are responsible for two main processes during protein synthesis on the ribosome , , . EF1A (or EF-Tu) is responsible for the selection and binding of the cognate aminoacyl-tRNA to the A-site (acceptor site) of the ribosome. EF2 (or EF-G) is responsible for the translocation of the peptidyl-tRNA from the A-site to the P-site (peptidyl-tRNA site) of the ribosome, thereby freeing the A-site for the next aminoacyl-tRNA to bind. Elongation factors are responsible for achieving accuracy of translation and both EF1A and EF2 are remarkably conserved throughout evolution. EF-G is a large, five-domain GTPase that promotes the directional movement of mRNA and tRNAs on the ribosome in a GTP-dependent manner. Unlike other GTPases, but by analogy to the myosin motor, EF-G performs its function of powering translocation in the GDP-bound form; that is, in a kinetically stable ribosome-EF-G(GDP) complex formed by GTP hydrolysis on the ribosome. The complex undergoes an extensive structural rearrangement, in particular affecting the small ribosomal subunit, which leads to mRNA-tRNA movement. Domain 4, which extends from the 'body' of the EF-G molecule much like a lever arm, appears to be essential for the structural transition to take place. In a hypothetical model, GTP hydrolysis induces a conformational change in the G domain of EF-G, which affects the interactions with neighbouring domains within EF-G. The resulting rearrangement of the domains relative to each other generates conformational strain in the ribosome to which EF-G is fixed. Because of structural features of the tRNA-ribosome complex, this conformational strain results in directional tRNA-mRNA movement. The functional parallels between EF-G and motor proteins suggest that EF-G differs from classical G-proteins in that it functions as a force-generating mechanochemical device rather than a conformational switch . Every completed bacterial genome has at least one copy, but some species have additional EF-G-like proteins. The closest homolog to canonical (e.g. Escherichia coli) EF-G in the spirochetes clusters as if it is derived from mitochondrial forms, while a more distant second copy is also present. Synechocystis sp. (strain PCC 6803) has a few proteins more closely related to EF-G than to any other characterised protein. Two of these resemble E. coli EF-G more closely than does the best match from the spirochetes; it may be that both function as authentic EF-G. More information about these proteins can be found at Protein of the Month: Elongation Factors . ; GO: 0003746 translation elongation factor activity, 0005525 GTP binding, 0006414 translational elongation, 0005622 intracellular.

Probab=99.17 E-value=1.1e-11 Score=97.72 Aligned_cols=432 Identities=17% Similarity=0.215 Sum_probs=195.6 Q ss_pred EEEECCCCCCHHHHHHHHH---CCCEEE--ECCCCC-CEEEEEEE-------------EEEECC------EEEEEEECCC Q ss_conf 9997189887888999985---885010--258985-30223899-------------999899------8999996588 Q gi|255764471|r 5 IAIVGAPNVGKSTLFNRLV---KKKMAV--VGNHPG-ITRDRLYG-------------QAIING------VIFNIVDTAG 59 (470) Q Consensus 5 iaivG~pNvGKStL~N~l~---~~~~ai--v~~~~g-~Trd~~~~-------------~~~~~~------~~~~liDT~G 59 (470) T Consensus 13 iGI~AHIDaGKTT~~ERILFy~g~~HkIgE~~g~dG~a~MDwME~E~ERGITItSAAT~~~Wk~~~~~~~~~~N~IDTPG 92 (705) T TIGR00484 13 IGISAHIDAGKTTTTERILFYTGRIHKIGEVHGKDGAATMDWMEQEKERGITITSAATTVEWKGMAKQYDHRINIIDTPG 92 (705) T ss_pred CCEEEEECCCCCCCHHEEEECCCCCCCEEECCCCCCCEECCHHHHCCCCCEEEECHHCCHHHHHHHHCCCCEEEEEECCC T ss_conf 43278633887320101000137501000001678851123123003587142100110102101000140378873789 Q ss_pred CCCCCHHHHHHHHHHHHHHHHHHCCEEEEEECCCCCCCHHHHHHHHHHHCCCCCCCCCHHHHCCCHHHHH--HHHH-HHH Q ss_conf 4207636899999999999998779899997598877623445553321023322220565223012100--1245-531 Q gi|255764471|r 60 IADGKNCSIAKQMNDQTELAINEAHLILFLIDSKAGITPYDHAITSFLRKKNIPIIIVSNKMDTRIAQRN--FYEI-YSL 136 (470) Q Consensus 60 ~~~~~~~~~~~~i~~~~~~ai~~aD~il~vvD~~~g~~~~D~~i~~~lr~~~~~~ilv~NK~D~~~~~~~--~~e~-~~l 136 (470) T Consensus 93 HVDFT~-EVER--------SlRVLDGAv~V~~a~~GV~pQ~~TVwRQa~~Y~VPRi~FVNK~Dk~GAnf~~~~~~~~~rL 163 (705) T TIGR00484 93 HVDFTV-EVER--------SLRVLDGAVAVLDAVGGVQPQSETVWRQANKYEVPRIVFVNKMDKTGANFLRVVNQLKSRL 163 (705) T ss_pred CEEEEE-EEEE--------HHHHHHHHHHHHHHCCCCCCCHHHHHHHHHHCCCCEEEEEECCCCCCCCHHHHHHHHHHHH T ss_conf 412578-8520--------1225645665333026866411567765432688628997155645787889999999874 Q ss_pred CCCCC---EEEHHHCC-CCCHHHHHHHHH------------------HHHHCCCCCCHHHHHCCCCCCCCCCCCCCCCCC Q ss_conf 22220---10011102-220147999999------------------861012345112210000111111222111233 Q gi|255764471|r 137 DFKEI---VEISAEHD-LGTSELHSVIFK------------------IFKQKYPNHPLEMIENNKRNEESPKENITSEGK 194 (470) Q Consensus 137 g~~~~---i~iSA~~g-~Gi~~L~~~i~~------------------~~~~~~~~~~~e~~e~~~~~ee~~~~~~~~e~~ 194 (470) T Consensus 164 ~~~~~~~qlpiGaE~~f~GviDLv~~ka~~~~~~~~g~~~~~~~iP~~~~~~~~~~~~~l~e~~a~~~~~LM~~yl~G~e 243 (705) T TIGR00484 164 GANAVPIQLPIGAEDKFIGVIDLVEMKAYFFEEGDKGTKIDEKEIPSDLLEQAKELRENLVEAVAELDEELMEKYLEGEE 243 (705) T ss_pred CCCCEEEEECCCCCCCCCEEEEEEEEEEEEECCCCCCCEEHHHCCCHHHHHHHHHHHHHHHHHHHCCCHHHHHHHCCCCC T ss_conf 67734664112566563104554301567750677664001222647899999999999999884200788998508965 Q ss_pred CCCCCCC---------CCEEEEEEE--CCCCCHHHHHHHHHCCCCCC--CHHHHHHHHHCCCCEEEEC--C------EEE Q ss_conf 4332344---------430388640--35642567887652012110--0024566542023114203--4------069 Q gi|255764471|r 195 SSVKNIS---------KPLRIAVVG--RPNVGKSTLINRLLGYNRLL--TGSQSGITRDSVSISWNWK--N------HPI 253 (470) Q Consensus 195 ~~~~~~~---------~~i~~~~~G--~pN~GKStl~N~l~~~~r~i--vs~~~GtTrD~i~~~~~~~--~------~~~ 253 (470) T Consensus 244 ~~~~~ik~~~r~g~l~~~~~pv~~GSafKNKGv~~lLDAV~~yLP~P~dv~~~~~~~~~~~~~e~~~~~sd~~~f~~LAF 323 (705) T TIGR00484 244 LTIEEIKNAIRKGVLNLELIPVLCGSAFKNKGVQLLLDAVVDYLPSPTDVPAIKGIDPDTNEEEIELKASDEEPFVALAF 323 (705) T ss_pred CCHHHHHHHHHCCEEEEEEEEEEECCCCHHHHHHHHHHHHHHHCCCCCCHHHHHCCCCCCCCCCEEEEECCCCCCEEEEE T ss_conf 36899988875131124688887503300025888999999747897431543023556677613675156765122345 Q ss_pred EEEECH------------HC-CCCCCCCC----HHHHHHCC--------CCCEEEECCEEEEEEC--CCCCC--CHHHHH Q ss_conf 998171------------10-44444300----01110001--------2100120120599845--53212--202122 Q gi|255764471|r 254 EIFDTA------------GM-RKPSRITE----SLEQKTVK--------KSMQSVRTCETTIVLL--DATIP--FEKQDL 304 (470) Q Consensus 254 ~liDTa------------Gi-rkk~~~~~----~~E~~s~~--------~t~~~i~~advvi~vi--Da~~~--~~~qd~ 304 (470) T Consensus 324 K~~tdpfvG~LTf~RvY~G~l~~G~~v~Ns~~~k~ervgRl~~MHa~~re~I~~~~aGdI~A~~Glkd~~TGdTl~d~~~ 403 (705) T TIGR00484 324 KVATDPFVGQLTFVRVYSGVLKSGSYVKNSRKSKKERVGRLVKMHANKREEIKEVRAGDIAAAIGLKDTTTGDTLCDEKA 403 (705) T ss_pred EECCCCCCCEEEEEEEEEEEECCCCEEEECHHHHHHHHHHHHHCCCCCCCCCCCCCCCCEEEEECCEECCCCCCCCCCCC T ss_conf 64058731127899997615127977760200001443233310037721001213563688731300256763225642 Q ss_pred HHHHHHHCCCCCCCEE-E---ECCCCCCCHHHHHHHHHHHCCCCCCCCCCCCCCCCCCCCCC----CHHHH-HHHHH-HH Q ss_conf 3200000035766558-9---44223354155566654201333200488311123453334----85899-99999-99 Q gi|255764471|r 305 RIVDSVFNTGHAVVLA-L---NKWDMVSDKLNLLQDLRTKAIKNLPQIGDIYINTISGRTGE----GLDDL-MVSVL-EI 374 (470) Q Consensus 305 ~i~~~i~~~~k~~iiv-~---NK~Dli~~~~~~~~~~~~~~~~~~~~~~~~~i~~iSA~~g~----gi~~l-~~~i~-~~ 374 (470) T Consensus 404 ~~~le~M~fp~PVI~~avePK~Kad~-----~kM~~AL~~la~EDP~F~----~~~~~E~g~TiI~GMGELHL~i~vdRm 474 (705) T TIGR00484 404 DVILESMEFPEPVISLAVEPKTKADQ-----EKMGIALGKLAEEDPTFR----TFTDEETGQTIIAGMGELHLDIIVDRM 474 (705) T ss_pred CCEEEECCCCCCEEEEEECCCCCCCH-----HHHHHHHHHHHCCCCCEE----EEECCCCCCHHHHCCCHHHHHHHHHHH T ss_conf 00010025888716887558874355-----679999875322488604----775274444132031045677886652 Q ss_pred HHHHHCCCCHHHHHHHHHHHHH--------HCCCCCCCCC----EEEEEEEEECC-CCCCEEEEEECCH--HHCCHHHHH Q ss_conf 9984146897898999999998--------2887877871----20699998628-7977899992582--238866899 Q gi|255764471|r 375 NKLWKTRITTSYLNSWLQKTQL--------QNPPPTIFNR----YNRLKYITQIQ-SSPPSFLIFCTFP--NKIPESYKR 439 (470) Q Consensus 375 ~~~~~~ri~T~~LN~~l~~~~~--------~~~pp~~~g~----~~ki~y~~Q~~-~~Pp~f~if~n~~--~~~~~~y~r 439 (470) T Consensus 475 kREFkvE~~~G~PQVayRET~~~~~~~~e~k~~k-QSGGrGQyG~V~i~~~P~~~~~~~~gyE-F~n~I~GGviP~EYIp 552 (705) T TIGR00484 475 KREFKVEANVGAPQVAYRETIRSKAEDVEGKYAK-QSGGRGQYGHVVIELEPLEPEEGGKGYE-FVNEIKGGVIPREYIP 552 (705) T ss_pred CCEEEEEEECCCCCCHHHHHHHHHHHHHCCEEEE-CCCCCCCCEEEEEEEECCCCCCCCCCCE-EEECCCCCCCCCCCHH T ss_conf 1003343305868303455431112321350323-0689873016899861277788876422-5330348607732103 Q ss_pred HHHHHHHHHC---CCCCCEE Q ss_conf 9999888976---8986448 Q gi|255764471|r 440 YLINRLRINF---SLSGIPI 456 (470) Q Consensus 440 yl~n~~r~~f---~~~g~pi 456 (470) T Consensus 553 ~v~~G~~~a~~~G~LaGyP~ 572 (705) T TIGR00484 553 AVDKGLQEALESGPLAGYPV 572 (705) T ss_pred HHHHHHHHHHHCCCEECCCE T ss_conf 67777999984697321434

HHsearch alignment for GI: 255764471 and conserved domain: TIGR00484