>cd06128 DNA_polA_exo The 3'-5' exonuclease domain of family-A DNA polymerases has a fundamental role in reducing polymerase errors and is involved in proofreading activity. Family-A DNA polymerases contain a DnaQ-like exonuclease domain in the same polypeptide chain as the polymerase domain, similar to family-B DNA polymerases. The exonuclease domain contains three conserved sequence motifs termed ExoI, ExoII and ExoIII, which are clustered around the active site and contain four invariant acidic residues that serve as ligands for the two metal ions required for catalysis. The Klenow fragment (KF) of Escherichia coli pol I, the Thermus aquaticus (Taq) pol I, and Bacillus stearothermophilus (BF) pol I are examples of family-A DNA polymerases. They are involved in nucleotide excision repair and in the processing of Okazaki fragments that are generated during lagging strand synthesis. The N-terminal domains of BF pol I and Taq pol I resemble the fold of the 3'-5' exonuclease domain of KF

Probab=99.92 E-value=5.5e-24 Score=176.87 Aligned_cols=151 Identities=18% Similarity=0.149 Sum_probs=118.7 Q ss_pred CEEEEEECCCCCCCCCCCCCHHHCCCCEEEEEEEEECCCEEEEEECCCCC----------HHHHHHHHHHCCCCCEEEEE Q ss_conf 78999804067887000460000268829999999838228999788842----------21799999864889819986 Q gi|254780127|r 2 SKLFIDIETRSPQPLPKVGVWAYAEQAVITLCAYAWDDEPVKLWDRTEQS----------AMPSDLLQYLRDETVMCVAH 71 (675) Q Consensus 2 k~l~lD~ET~s~~dl~~~Gl~~y~~~~~I~~i~~a~~~~~~~~~d~~~~~----------~~~~~l~~~L~~~~~~kv~H 71 (675) T Consensus 2 ~~~a~DtETt~ld~~----------~a~iVGis~s~~~~~a~YiP~~h~~~~~~~~l~~~~vl~~L~p~led~~i~Kigh 71 (166) T cd06128 2 PVFAFDTETDSLDNI----------SANLVGLSFAIEPGVAAYIPVAHDYLDAPDQISRERALELLKPLLEDEKALKVGQ 71 (166) T ss_pred CEEEEECCCCCCCCC----------CCEEEEEEEECCCCEEEEEECCCCCCCCHHHHHHHHHHHHHHHHHCCCCCCEEEE T ss_conf 989997887998904----------3549999998008969999526776675257789999999999973999764531 Q ss_pred EHHHHHHHHHHHCCCCCCCCCEEEHHHHHHHHCC---CCCHHHHHH-HHCCCCCCHHHHHCHHHHHHHHHHHHHHCCCCC Q ss_conf 3077599999862998786504545889998588---999789999-808898652766376576641002332013453 Q gi|254780127|r 72 NSLFERILFKKTLGIDIPSKRWICTSVLARTNGL---PSSLKNACL-ALNFSEHLTKMEEGKALIARFCKGSIDSPPYDC 147 (675) Q Consensus 72 Na~FD~~vL~~~lGi~i~~~~~~DTmi~A~~l~~---p~sL~~la~-~lgl~~~~~kd~~gk~li~~~~~~~~~~~~~~~ 147 (675) T Consensus 72 NlK~D~~vL~~~-Gi~l~g-~~fDTMlaaylldp~~~~h~Ld~La~~~L~~~~i~~~dl~GkGk------~q-------~ 136 (166) T cd06128 72 NLKYDRGILANY-GIELRG-IAFDTMLESYILNSVAGRHDMDSLAERWLKHKTITFEEIAGKGK------NQ-------L 136 (166) T ss_pred CHHHHHHHHHHC-CCCCCC-CCCCHHHHHHHCCCCCCCCCHHHHHHHHCCCCCEEHHHHHCCCC------CC-------C T ss_conf 156679999619-966899-98457679876289998899699999983998705999837885------75-------8 Q ss_pred CCCCCHHHHHHHHHHHHHHHHHHHHHHHHHCC Q ss_conf 11258768999898877539999999987200 Q gi|254780127|r 148 TRANHVQAWQLFGEYCKRDVEATRELFKRLIP 179 (675) Q Consensus 148 ~~~~~~~~~~~~~~Ya~~Dv~~~~~L~~~L~~ 179 (675) T Consensus 137 ~f~--~v~i~~~~~YA~eDAd~t~rL~~~l~P 166 (166) T cd06128 137 TFN--QIALEEAGRYAAEDADVTLQLHLKMWP 166 (166) T ss_pred CCC--CCCHHHHHHHHHHHHHHHHHHHHHHCC T ss_conf 932--289999999899999999999985389

HHsearch alignment for GI: 254780127 and conserved domain: cd06128