>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=99.93 E-value=7.6e-25 Score=179.22 Aligned_cols=151 Identities=18% Similarity=0.189 Sum_probs=115.7 Q ss_pred CEEEEEECCCCCCCCCCCCCHHHCCCCEEEEEEEEECCEEEEEEECCCC----------HHHHHHHHHHHCCCCCEEEEE Q ss_conf 6899981417898700044001127981999999984803999978881----------043799999863889819997 Q gi|254781193|r 2 ATLFIDFETRSPIDLTKCGICKYAEDVCVILFAFGFDDHPVELWDCVHD----------PVMPQVLKEALENTDVTIVAH 71 (675) Q Consensus 2 k~i~lD~ET~~~~dl~~~Gl~~y~~~~~i~~i~~a~~~~~v~~~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 PVFAFDTETDSLDN----------ISANLVGLSFAIEPGVAAYIPVAHDYLDAPDQISRERALELLKPLLEDEKALKVGQ 71 (166) T ss_pred CEEEEECCCCCCCC----------CCCEEEEEEEECCCCEEEEEECCCCCCCCHHHHHHHHHHHHHHHHHCCCCCCEEEE T ss_conf 98999788799890----------43549999998008969999526776675257789999999999973999764531 Q ss_pred EHHHHHHHHHHHCCCCCCCCCEEEHHHHHHHHCC---CCCHHHHHHHC-CCCCCHHHHHHHHHHHHCCCCCCCCCCCCCC Q ss_conf 3077499999860899884203316889998678---99968989982-9981100437999986202112343323467 Q gi|254781193|r 72 NSYFERTVLKACFNLDIPIHRWICTLVLARSNGL---PSALKAVGEAL-KLSSQKMEEGKELIARFCKGETHECLYDRNK 147 (675) Q Consensus 72 Na~FD~~~L~~~~Gi~i~~~~~~DTmi~A~~l~~---~~sL~~la~~l-~l~~~k~~~~k~l~~~~~k~~~~~~~~~~~~ 147 (675) T Consensus 72 NlK~D~~vL~~~-Gi~l~-g~~fDTMlaaylldp~~~~h~Ld~La~~~L~~~---~i~~~dl~G---k-------Gk~q~ 136 (166) T cd06128 72 NLKYDRGILANY-GIELR-GIAFDTMLESYILNSVAGRHDMDSLAERWLKHK---TITFEEIAG---K-------GKNQL 136 (166) T ss_pred CHHHHHHHHHHC-CCCCC-CCCCCHHHHHHHCCCCCCCCCHHHHHHHHCCCC---CEEHHHHHC---C-------CCCCC T ss_conf 156679999619-96689-998457679876289998899699999983998---705999837---8-------85758 Q ss_pred CCCHHHHHHHHHHHHHHHHHHHHHHHHCCC Q ss_conf 858532899999989989999999963010 Q gi|254781193|r 148 PNHREAWRLFGEYCKGDVTVTREIFKRLEP 177 (675) Q Consensus 148 ~~~~~~~~~~~~Ya~~Dv~~t~~L~~~l~~ 177 (675) T Consensus 137 ~f~~v~i~~~~~YA~eDAd~t~rL~~~l~P 166 (166) T cd06128 137 TFNQIALEEAGRYAAEDADVTLQLHLKMWP 166 (166) T ss_pred CCCCCCHHHHHHHHHHHHHHHHHHHHHHCC T ss_conf 932289999999899999999999985389

HHsearch alignment for GI: 254781193 and conserved domain: cd06128