>cd04677 Nudix_Hydrolase_18 Members of the Nudix hydrolase superfamily catalyze the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+, for their activity and contain a highly conserved 23-residue nudix motif (GX5EX7REUXEEXGU, where U = I, L or V), which functions as a metal binding and catalytic site. Substrates of nudix hydrolases include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the nudix hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance & "house-cleaning" enzymes. Substrate specificity is used to define families within the superfamily. Differences in substrate

Probab=99.92 E-value=1.7e-25 Score=168.92 Aligned_cols=124 Identities=23% Similarity=0.284 Sum_probs=83.4 Q ss_pred CCCEEEEEEECCCCCEEEEEECCCCCCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHHHCCCCCCCCCCCCCCEEECCCCC Q ss_conf 56606999984898399999268877666872201211507888888999999999837552222201366124116322 Q gi|254780557|r 2 YRRGVGILILNQDDLVWVGRRCFHDNNKHLSLWQMPQGGINPQEDPLDAAYRELYEETGIKSISLLGQGDSYIQYDFPAH 81 (160) Q Consensus 2 yR~~V~vvi~n~~~~iLl~kR~~~~~~~~~g~W~~PgG~ve~gEt~~~Aa~REl~EEtGi~~~~~~~~~~~~~~~~~~~~ 81 (160) T Consensus 6 ~~~g~~~vv~~~~g~vLL~~r~~------~g~W~lPGG~ve~gEt~~~aa~RE~~EEtGi~~~~~~~~~----~~~~~~~ 75 (132) T cd04677 6 ILVGAGVILLNEQGEVLLQKRSD------TGDWGLPGGAMELGESLEETARRELKEETGLEVEELELLG----VYSGKEF 75 (132) T ss_pred EEEEEEEEEEECCCEEEEEEECC------CCCEECCEEEECCCCCHHHHHHHHHHHHHCCEEEEEEEEE----EECCCEE T ss_conf 78579999998999899999889------9949898427669979999999999998695535247999----9778645 Q ss_pred CCC--CCCCCCCCCEEEEEEECCCCCCEECCCCCCCCCCCCCEEEECCHHHHHHCCHHCCHHHH Q ss_conf 200--00112344337999980475430105788888886003760378997630000137999 Q gi|254780557|r 82 CIQ--ENGYVGQMQKWFAFRFQGLTSEICVDRTAYGYESEFDAWTWVSLWDTPNIVVDFKKEAY 143 (160) Q Consensus 82 ~~~--~~~~~~~~~~~~~~~~~~~~~~i~~~~~~~~~~~E~~~~~Wv~~~el~~~i~~fk~~vy 143 (160) T Consensus 76 ~~~~~~~~~~~~~~~~~~~~~~~~--------~~~~~~~E~~e~~Wf~~delp~l~~p~~r~~i 131 (132) T cd04677 76 YVKPNGDDEQYIVTLYYVTKVFGG--------KLVPDGDETLELKFFSLDELPELINPQHKEML 131 (132) T ss_pred EECCCCCCEEEEEEEEEEEEECCC--------CCCCCCCCEEEEEEECHHHCCCCCCHHHHHHC T ss_conf 544899847999999999862587--------56799970158999829998344892257560

HHsearch alignment for GI: 254780557 and conserved domain: cd04677