>cd00397 DNA_BRE_C DNA breaking-rejoining enzymes, C-terminal catalytic domain. The DNA breaking-rejoining enzyme superfamily includes type IB topoisomerases and tyrosine recombinases that share the same fold in their catalytic domain containing six conserved active site residues. The best-studied members of this diverse superfamily include human topoisomerase I, the bacteriophage lambda integrase, the bacteriophage P1 Cre recombinase, the yeast Flp recombinase and the bacterial XerD/C recombinases. Their overall reaction mechanism is essentially identical and involves cleavage of a single strand of a DNA duplex by nucleophilic attack of a conserved tyrosine to give a 3' phosphotyrosyl protein-DNA adduct. In the second rejoining step, a terminal 5' hydroxyl attacks the covalent adduct to release the enzyme and generate duplex DNA. The enzymes differ in that topoisomerases cleave and then rejoin the same 5' and 3' termini, whereas a site-specific recombinase transfers a 5' hydroxyl gener

Probab=99.92 E-value=5.1e-25 Score=181.15 Aligned_cols=147 Identities=22% Similarity=0.304 Sum_probs=118.6 Q ss_pred HHHHHHHHHCCC--CHHHHHHHHHHHCCCCCCCCCCCCCCEEE--EECCCCCCCCCHHHHHHCCHHHHHHHHHHHC---- Q ss_conf 445666640378--08999989898618873100256640144--3023321133102433112168999996420---- Q gi|254780134|r 178 DMQQFKSFWSEG--SQPRLAFEFLLYSGLRCSDSCRAGVQHLQ--NNIFSIKTQKTGTIITVELPDGFMKLLAMTP---- 249 (348) Q Consensus 178 ei~~~~~~~~~~--~~~~~~~~l~~~TG~R~~Ei~~L~~~did--~~~i~~~~~Kt~~~~~vpl~~~l~~~l~~~~---- 249 (348) T Consensus 1 e~~~~~~~~~~~~~~r~r~~~~l~~~tGlR~~Ei~~L~~~di~~~~~~i~i~~~K~~~~r~vpi~~~~~~~l~~~~~~~~ 80 (164) T cd00397 1 EIERLLAAAEASTPERLYLALLLLLATGLRISELCALRWSDIDLDKRVIHITGTKTKKERTVPLSEEALKLLKEYLKKRR 80 (164) T ss_pred CHHHHHHHHHHCCCHHHHHHHHHHHHHCCCHHHHHCCCCCCCCCCCCEEEEECCCCCCCCCCCCCCHHHHHHHHHHHHHC T ss_conf 98999976514679889999999999781999996384620567764799835646653336676012346888898850 Q ss_pred ---CCCCCCCCCCCCCC---CCHHHHHHHHHHHHHHCCCC---CCCCHHHHHHHHHHHHCCCCHHHHHHHHCCCCHHHHH Q ss_conf ---13322112224577---58778999999999983889---9814026999999998489988999996499989999 Q gi|254780134|r 250 ---IGKETFFINNDKQK---MNATQFSIWFKAKATKAGVN---KSAHGVRKFSATISADAGATAHELMATYGWKTVDQAE 320 (348) Q Consensus 250 ---~~~~~~~~~~~g~~---~~~~~~~~~~~~~~~~agi~---~~~H~lRht~at~l~~~G~~~~~i~~~lGHss~~~t~ 320 (348) T Consensus 81 ~~~~~~~~lf~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~H~lRht~at~l~~~g~~~~~I~~~lGHs~~~tT~ 160 (164) T cd00397 81 PANGDEEYLFPSRRGGPAATLSRRNVKRIFKAAGRRAGIDKEGLTPHSLRHTFASALLNAGLDLEAVQDLLGHSSIAMTM 160 (164) T ss_pred CCCCCCCCEEECCCCCCCCCHHHHHHHHHHHHHHHHHCCCCCCCCCCCCHHHHHHHHHHCCCCHHHHHHHHCCCCHHHHH T ss_conf 14687541211368986652046789999789999833676567756658999999999699999999996899988971 Q ss_pred HHHH Q ss_conf 9999 Q gi|254780134|r 321 TYTK 324 (348) Q Consensus 321 ~Y~~ 324 (348) T Consensus 161 ~Y~h 164 (164) T cd00397 161 RYAH 164 (164) T ss_pred HCCC T ss_conf 1839

HHsearch alignment for GI: 254780134 and conserved domain: cd00397