>TIGR01054 rgy reverse gyrase; InterPro: IPR005736 DNA topoisomerases regulate the number of topological links between two DNA strands (i.e. change the number of superhelical turns) by catalysing transient single- or double-strand breaks, crossing the strands through one another, then resealing the breaks. These enzymes have several functions: to remove DNA supercoils during transcription and DNA replication; for strand breakage during recombination; for chromosome condensation; and to disentangle intertwined DNA during mitosis , . DNA topoisomerases are divided into two classes: type I enzymes (5.99.1.2 from EC; topoisomerases I, III and V) break single-strand DNA, and type II enzymes (5.99.1.3 from EC; topoisomerases II, IV and VI) break double-strand DNA . Type I topoisomerases are ATP-independent enzymes (except for reverse gyrase), and can be subdivided according to their structure and reaction mechanisms: type IA (bacterial and archaeal topoisomerase I, topoisomerase III and reverse gyrase) and type IB (eukaryotic topoisomerase I and topoisomerase V). These enzymes are primarily responsible for relaxing positively and/or negatively supercoiled DNA, except for reverse gyrase, which can introduce positive supercoils into DNA. Reverse gyrase is a type IA topoisomerase that is unique among these enzymes in its requirement for ATP. Reverse gyrase is a hyperthermophile-specific enzyme that acts as a renaturase by positively supercoiling DNA, and by annealing complementary single-strand circles . Hyperthermophilic organisms must protect themselves against heat-induced degradation, and reverse gyrase acts to reduce the rate of double-strand DNA breakage, a function that does not require ATP hydrolysis and which is independent of its positive supercoiling abilities. Reverse gyrase achieves this by recognising nicked DNA and recruiting a protein coat to the site of damage . More information about this protein can be found at Protein of the Month: DNA Topoisomerase .; GO: 0003677 DNA binding, 0003916 DNA topoisomerase activity, 0006265 DNA topological change, 0006268 DNA unwinding during replication, 0005694 chromosome.

Probab=99.34 E-value=6.3e-10 Score=97.42 Aligned_cols=281 Identities=19% Similarity=0.264 Sum_probs=201.1 Q ss_pred HHHHHHHHHCCCCCCHHHHHHHHHHHHHHCCCCCCEEEEEECCCCCHHHHHHHHHHHHHHH-HCCEEEEEHHHHHHHHHH Q ss_conf 7899998630246798899999999984100134307886214422369999997334443-054588612799999999 Q gi|254780945|r 260 KIAQKILRNIPFSPTKSQESAIKDILQDMSQKNRMLRILQGDVGSGKTLVALIAMAAAVEA-GGQAVIMAPIGILAQQHY 338 (700) Q Consensus 260 ~~~~~f~~~LPF~LT~~Q~~ai~eI~~Dl~~~~pM~RLLQGDVGSGKTiVA~~A~l~~~~~-G~Q~alMaPTEILA~QH~ 338 (700) T Consensus 72 ~f~~FF~~~~G~~pws~Qk~WAKRv~~~~S--Fa----i~APTGVGKttFG~~mslflA~kKGkR~y~ilPT~lLv~Qv~ 145 (1843) T TIGR01054 72 EFEEFFKKAVGSEPWSIQKSWAKRVLKGDS--FA----IVAPTGVGKTTFGLVMSLFLAKKKGKRSYIILPTTLLVKQVA 145 (1843) T ss_pred HHHHHHHHHHCCCCHHHHHHHHHHHHCCCC--EE----EECCCCCCHHHHHHHHHHHHHHHCCCEEEEEECHHHHHHHHH T ss_conf 999999997188843567999999641796--48----980588767799999999986542987899947078899999 Q ss_pred HHHHHHCCCCCCEEE----EEECCCCHHHHHHHHHHHCCCCCEEEEECHHHCCCC-------CCCCCCCEEEECCCC--- Q ss_conf 862110145786589----962464225667687762134754864111201334-------554444178852101--- Q gi|254780945|r 339 EFIKKYTQNTQIIVE----IITGNMPQAHRRKALERIAHGQAHIIIGTHALFQDS-------IQYYKLILVIVDEQH--- 404 (700) Q Consensus 339 ~~~~~~~~~~~i~v~----lLtg~~~~~er~~i~~~i~~G~~~iiIGTHAL~q~~-------v~F~~LgLvViDEQH--- 404 (700) T Consensus 146 ~kl~~~~~k~g~~~~~l~~~yhS~L~~~~kke~~Eri~~GDfdilitT~~FL~K~~~~L~~~y~F~---liFVDDVDa~L 222 (1843) T TIGR01054 146 EKLSSLAEKEGVGIVRLLGAYHSKLSTKEKKEVKERIENGDFDILITTSMFLSKNFDKLKNQYKFD---LIFVDDVDALL 222 (1843) T ss_pred HHHHHHCCCCCCCCEEEEEEEECCCCHHHHHHHHHHHHCCCEEEEHHHHHHHHHHHHHCCCCCEEE---EEEEECHHHHH T ss_conf 998752002575000022210112654567889998731891786122468887665178985144---89971536763 Q ss_pred -----------------------------------------C----CCHHHHHHHHHC---------------CCCCCCE Q ss_conf -----------------------------------------3----356889987402---------------5677610 Q gi|254780945|r 405 -----------------------------------------R----FGVQQRLKLTQK---------------ATAPHVL 424 (700) Q Consensus 405 -----------------------------------------R----FGV~QR~~L~~K---------------g~~ph~L 424 (700) T Consensus 223 k~skNVD~~L~LlGF~eE~i~~a~~~i~L~~k~~k~~~~~~~~~~~~R~E~~~~~LE~~~r~~~~~a~~~~krGr~g~Li 302 (1843) T TIGR01054 223 KASKNVDKILKLLGFSEELIEKAYELIKLKLKENKLEEDLAREKIVVRLEARKKLLEAKRRLEKLEAEIKKKRGRKGVLI 302 (1843) T ss_pred HCCCCHHHHHHHHCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCEEEE T ss_conf 16555667775517889999999999999887643577888888864678889999999998987764743248864699 Q ss_pred EECHHHHHHHHHHHHHHCC-CHHHHCCCCC-CCCCCEEEEEECCCHHHHHHH---HHHHHCCCCEEEEEECCCCCCCCCC Q ss_conf 1010132278999975201-0111102355-766620799970200268999---9763103873899971201221112 Q gi|254780945|r 425 LMTATPIPRTLVLTSLGDI-DISKITEKPA-GRKPIKTVIIPINRIDEVIER---LKVVLSEGKKAYWICPQIEEKKESN 499 (700) Q Consensus 425 ~MtATPIPRTLal~~ygdl-dvS~i~e~P~-gR~~I~T~~~~~~~~~~~~~~---i~~~l~~g~q~y~VcPlIeese~~~ 499 (700) T Consensus 303 vsSATG~prG~r~~LFR~LL~FevG~~~~~GLRnvvD~y~~~~d~v~E~~~~sve~v~~LG~GGlVyv-------s~~yG 375 (1843) T TIGR01054 303 VSSATGKPRGKRVKLFRELLGFEVGKGSDTGLRNVVDVYEEDEDGVKEKLLESVELVKKLGKGGLVYV-------SIDYG 375 (1843) T ss_pred EEECCCCCCCCHHHHHHHHCCCCCCCCCCCCCCCEEEEEECCCCCHHHHHHHHHHHHHHHCCCEEEEE-------ECCCC T ss_conf 98514888761336536552710057642233213885114888446889999999998479439997-------12225 Q ss_pred CCHHHHHHHHHHHHCCCCEECCCCCCCHHHHHHHHHHHHCCCEEEEEECH----HHHCCCCCCCCC Q ss_conf 10146666666866371031201469989999999997559869999800----341046888765 Q gi|254780945|r 500 FRSVVERFNSLHEHFTSSIAIIHGRMSDIDKESVMDSFKNGTCKLLIATT----VIEVGIDVVDAS 561 (700) Q Consensus 500 ~~~~~~~~~~l~~~~~~~v~~lHGkm~~~ek~~~m~~F~~g~~~iLvaTt----viEVGvdvpna~ 561 (700) T Consensus 376 ~e~a~ei~~~L~~~-Gv~A~~~~~~k----~~~~~~~F~~GE~dVliG~a~yyg~LVRGLDLP~rv 436 (1843) T TIGR01054 376 KEKAEEIKEFLREH-GVKAVAYHAKK----PKEDLEKFAEGEIDVLIGVASYYGVLVRGLDLPERV 436 (1843) T ss_pred HHHHHHHHHHHHHC-CCEEEEEEECC----CCCCHHHHHCCCEEEEEEEECCCCCEEECCCCCCHH T ss_conf 58999999999857-94799984037----732034663485136877101547635326661010

HHsearch alignment for GI: 254780945 and conserved domain: TIGR01054