>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=97.89 E-value=2.7e-05 Score=61.08 Aligned_cols=308 Identities=16% Similarity=0.320 Sum_probs=135.7 Q ss_pred CCCCHHHHHHHHHCCCCCCHHHHHHHHHHHHHHCCCCCCEEEEEECCCCCHHHHHHHHHHHHHHHHCCEEEEEHHHHHHH Q ss_conf 87757899998630246798899999999984100134307886214422369999997334443054588612799999 Q gi|254780945|r 256 NVEGKIAQKILRNIPFSPTKSQESAIKDILQDMSQKNRMLRILQGDVGSGKTLVALIAMAAAVEAGGQAVIMAPIGILAQ 335 (700) Q Consensus 256 ~~~~~~~~~f~~~LPF~LT~~Q~~ai~eI~~Dl~~~~pM~RLLQGDVGSGKTiVA~~A~l~~~~~G~Q~alMaPTEILA~ 335 (700) T Consensus 309 ~prG~r~~LFR~LL~FevG~~~~~GLRnvvD~y~~~~--------d-~v~E~~~~sve~v~~L--G~GGlVyvs~~y-G~ 376 (1843) T TIGR01054 309 KPRGKRVKLFRELLGFEVGKGSDTGLRNVVDVYEEDE--------D-GVKEKLLESVELVKKL--GKGGLVYVSIDY-GK 376 (1843) T ss_pred CCCCCHHHHHHHHCCCCCCCCCCCCCCCEEEEEECCC--------C-CHHHHHHHHHHHHHHH--CCCEEEEEECCC-CH T ss_conf 8876133653655271005764223321388511488--------8-4468899999999984--794399971222-55 Q ss_pred HHHHHHHHHCCCCCCEEEEEECCCCHHHHHHHHHHHCCCCCEEEEECHHHC---CCCCCCCC-CCEEEEC--CCCCCCHH Q ss_conf 999862110145786589962464225667687762134754864111201---33455444-4178852--10133568 Q gi|254780945|r 336 QHYEFIKKYTQNTQIIVEIITGNMPQAHRRKALERIAHGQAHIIIGTHALF---QDSIQYYK-LILVIVD--EQHRFGVQ 409 (700) Q Consensus 336 QH~~~~~~~~~~~~i~v~lLtg~~~~~er~~i~~~i~~G~~~iiIGTHAL~---q~~v~F~~-LgLvViD--EQHRFGV~ 409 (700) T Consensus 377 e~a~ei~~~L~~~Gv~A~~~~~~k----~~~~~~~F~~GE~dVliG~a~yyg~LVRGLDLP~rvRYAvF~G~Pk~k~~~~ 452 (1843) T TIGR01054 377 EKAEEIKEFLREHGVKAVAYHAKK----PKEDLEKFAEGEIDVLIGVASYYGVLVRGLDLPERVRYAVFLGVPKFKVPLK 452 (1843) T ss_pred HHHHHHHHHHHHCCCEEEEEEECC----CCCCHHHHHCCCEEEEEEEECCCCCEEECCCCCCHHEEEEECCCCCEEEEEE T ss_conf 899999999985794799984037----7320346634851368771015476353266610100023438995066412 Q ss_pred ------HHH-HHHHCCC--CCCCEEECHHHHHHHHHHHHHHCCCHHHHCCCCCC-------CCCCEE----EEEECCC-- Q ss_conf ------899-8740256--77610101013227899997520101111023557-------666207----9997020-- Q gi|254780945|r 410 ------QRL-KLTQKAT--APHVLLMTATPIPRTLVLTSLGDIDISKITEKPAG-------RKPIKT----VIIPINR-- 467 (700) Q Consensus 410 ------QR~-~L~~Kg~--~ph~L~MtATPIPRTLal~~ygdldvS~i~e~P~g-------R~~I~T----~~~~~~~-- 467 (700) T Consensus 453 ~~~~~p~~~~~LLSl~~~~~~e~~i~~~~~~~~~~~~~L~r~~~ls~~e~~~~~~~~~~~~~~e~~~Gydr~i~e~~~~~ 532 (1843) T TIGR01054 453 VALSSPRRLLALLSLLALILKEERIESLAEKARKLLGRLKRYIDLSVIERALEEKLEARRARGEVKEGYDRIIEEVLKFL 532 (1843) T ss_pred ECCCCHHHHHHHHHHHHHHHCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCHHHHHHHHHHHHHHHHH T ss_conf 03787578999999999851432035789999999999988654443328889999852376502201568999888778 Q ss_pred -----HHHHHHH-HHH-----HHCCCCEEEEEECCCC----CCCCC--------------CCCHHHHHHHHHHHHCC--- Q ss_conf -----0268999-976-----3103873899971201----22111--------------21014666666686637--- Q gi|254780945|r 468 -----IDEVIER-LKV-----VLSEGKKAYWICPQIE----EKKES--------------NFRSVVERFNSLHEHFT--- 515 (700) Q Consensus 468 -----~~~~~~~-i~~-----~l~~g~q~y~VcPlIe----ese~~--------------~~~~~~~~~~~l~~~~~--- 515 (700) T Consensus 533 ~~~L~~e~~~~~G~~~~~~~~~~~~e~~~ylvvpD~~tYiQASGRTSRl~aGGlTkGlS~Vl~dd~~~~~aL~kr~~lyy 612 (1843) T TIGR01054 533 REALKREDVLEKGIKESEDLSLVAKEGKLYLVVPDVKTYIQASGRTSRLYAGGLTKGLSVVLVDDPEAFEALKKRLKLYY 612 (1843) T ss_pred HHHHHHHHHHHCCCCCCCCEEEECCCCEEEEEECCCCCCCCCCCHHHHHHHHHHHHCCEEEEECCHHHHHHHHHHHHHHH T ss_conf 88775202553265410344786179725999668774424674156655423230534899654789999998886666 Q ss_pred CCEECCCCCCCHHHHHHHHHHHHCC--CEEEEEECHHHHCCCCCCCCCEEEEECHH-------HCCHHHHHHH Q ss_conf 1031201469989999999997559--86999980034104688876589985852-------5474688773 Q gi|254780945|r 516 SSIAIIHGRMSDIDKESVMDSFKNG--TCKLLIATTVIEVGIDVVDASIIIIENAE-------HFGLAQLHQL 579 (700) Q Consensus 516 ~~v~~lHGkm~~~ek~~~m~~F~~g--~~~iLvaTtviEVGvdvpna~~mvI~~ae-------rfGLsqLHQL 579 (700) T Consensus 613 ~~~ei~fk~i~EVDL~~l~rEIDEdR~k~r~~~~g~~~A~~~dLvKt~L~vVESPnKARTIA~FFGkP~~R~i 685 (1843) T TIGR01054 613 FTQEIEFKRIDEVDLEKLLREIDEDREKVRRIVEGKVKAKVKDLVKTALLVVESPNKARTIARFFGKPSVRKI 685 (1843) T ss_pred HHHCCCCCCCCCCCHHHHHHHHHHCCCCCCEEEECCEEEEEECCCCCEEEEEECCCCHHHHHHHCCCCCCEEC T ss_conf 5201355445600178887764101012401220762664202424137998278604455343069963551

HHsearch alignment for GI: 254780945 and conserved domain: TIGR01054