>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=99.95 E-value=3e-27 Score=194.71 Aligned_cols=283 Identities=23% Similarity=0.343 Sum_probs=197.9 Q ss_pred CCCCCCCHHHHHHHHHHHCCCCEEEECCCCCCHHHHHHHHHHHHHHCCCCCCCCCEEEEECCCHHHHHHHHHHHHHHCCC Q ss_conf 87987898999999999769979998279851789999999999860652147827999828589999999998741023 Q gi|254780382|r 19 AGYVKPTPIQIKTIPLVLQRHDVCGIAQTGTGKTASFVLPMLTILEKGRARVRMPRTLILEPTRELAAQVADNFEKYGKN 98 (465) Q Consensus 19 ~~~~~pt~iQ~~~i~~~l~g~dvi~~apTGsGKT~~~~lp~l~~l~~~~~~~~~~~~lil~PtreLa~Qi~~~~~~~~~~ 98 (465) T Consensus 81 ~G~~-pws~Qk~WAKRv~~~~SFai~APTGVGKt-tFG~~mslflA~----kKGkR~y~ilPT~lLv~Qv~~kl~~~~~k 154 (1843) T TIGR01054 81 VGSE-PWSIQKSWAKRVLKGDSFAIVAPTGVGKT-TFGLVMSLFLAK----KKGKRSYIILPTTLLVKQVAEKLSSLAEK 154 (1843) T ss_pred HCCC-CHHHHHHHHHHHHCCCCEEEECCCCCCHH-HHHHHHHHHHHH----HCCCEEEEEECHHHHHHHHHHHHHHHCCC T ss_conf 1888-43567999999641796489805887677-999999999865----42987899947078899999998752002 Q ss_pred CCCCCC----CCCCCCCCCCCC---CCCCC-HHHHHHCCCCHHHHHHHCCCCCCC---CCEEECCCCCCCCCC------- Q ss_conf 332210----000122222222---22210-112210221023333200000012---100102551000000------- Q gi|254780382|r 99 YNLTVA----LLIGGIPFEAQN---KKLER-GADVLICTPGRILDHFNRGKLLMN---NIEILVIDEADRMLD------- 160 (465) Q Consensus 99 ~~l~~~----~~~gg~~~~~~~---~~l~~-~~~IiV~TP~rl~~~l~~~~~~l~---~~~~lViDEah~l~~------- 160 (465) T Consensus 155 ~g~~~~~l~~~yhS~L~~~~kke~~Eri~~GDfdilitT~----~FL~K~~~~L~~~y~F~liFVDDVDa~Lk~skNVD~ 230 (1843) T TIGR01054 155 EGVGIVRLLGAYHSKLSTKEKKEVKERIENGDFDILITTS----MFLSKNFDKLKNQYKFDLIFVDDVDALLKASKNVDK 230 (1843) T ss_pred CCCCCEEEEEEEECCCCHHHHHHHHHHHHCCCEEEEHHHH----HHHHHHHHHCCCCCEEEEEEEECHHHHHHCCCCHHH T ss_conf 5750000222101126545678899987318917861224----688876651789851448997153676316555667 Q ss_pred ----CCCHHH-HHHH--------------------------------------HH---HHCCCC---C--CCCCCCCCCC Q ss_conf ----010035-7887--------------------------------------54---310222---2--2333432112 Q gi|254780382|r 161 ----MGFIPY-IQNI--------------------------------------TS---LVPFTR---Q--TLLFSATMTD 189 (465) Q Consensus 161 ----~gf~~~-i~~i--------------------------------------~~---~~~~~~---q--~i~~SAT~~~ 189 (465) T Consensus 231 ~L~LlGF~eE~i~~a~~~i~L~~k~~k~~~~~~~~~~~~R~E~~~~~LE~~~r~~~~~a~~~~krGr~g~LivsSATG~p 310 (1843) T TIGR01054 231 ILKLLGFSEELIEKAYELIKLKLKENKLEEDLAREKIVVRLEARKKLLEAKRRLEKLEAEIKKKRGRKGVLIVSSATGKP 310 (1843) T ss_pred HHHHHCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCEEEEEEECCCCC T ss_conf 77551788999999999999988764357788888886467888999999999898776474324886469998514888 Q ss_pred CC--CCCCCCCCCCCCCCCCCCCCCC-CCCCCCCCCCCCCCCCHHHHHHHH---CCCCCCCCCEEEEEECCC---CCCCC Q ss_conf 22--2111122222100134443212-346421111122221102444321---012234565067762134---43222 Q gi|254780382|r 190 EL--QKVSENFLQNPKRIEVNTPSST-AETIEHCFVATYAQYSKKCALLQQ---LLQSQDTMKNGIIFCNQK---KNVVN 260 (465) Q Consensus 190 ~v--~~l~~~~l~~~~~i~v~~~~~~-~~~i~~~~~~~~~~~~~k~~~l~~---l~~~~~~~~k~iIF~~t~---~~~~~ 260 (465) T Consensus 311 rG~r~~LFR~LL----~FevG~~~~~GLRnvvD~y~~~~d~---v~E~~~~sve~v~~L--G~GGlVyvs~~yG~e~a~e 381 (1843) T TIGR01054 311 RGKRVKLFRELL----GFEVGKGSDTGLRNVVDVYEEDEDG---VKEKLLESVELVKKL--GKGGLVYVSIDYGKEKAEE 381 (1843) T ss_pred CCCHHHHHHHHC----CCCCCCCCCCCCCCEEEEEECCCCC---HHHHHHHHHHHHHHH--CCCEEEEEECCCCHHHHHH T ss_conf 761336536552----7100576422332138851148884---468899999999984--7943999712225589999 Q ss_pred CCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHCCCCCEEEEEH----HHHHHHHCCCC-CCEEEEECCCC Q ss_conf 222222233222223454203332344442013552388884----66464407887-65002002467 Q gi|254780382|r 261 LCHSLEKQGFSVCAIHGNIDQRSRMKILSNFKEGTIQLMVAS----DLAARGLDIPD-VGHVFNFDVPN 324 (465) Q Consensus 261 l~~~L~~~g~~v~~lhg~l~~~~R~~~~~~F~~g~~~vLV~T----d~~~~GiDip~-v~~VI~~d~P~ 324 (465) T Consensus 382 i~~~L~~~Gv~A~~~~~~k~----~~~~~~F~~GE~dVliG~a~yyg~LVRGLDLP~rvRYAvF~G~Pk 446 (1843) T TIGR01054 382 IKEFLREHGVKAVAYHAKKP----KEDLEKFAEGEIDVLIGVASYYGVLVRGLDLPERVRYAVFLGVPK 446 (1843) T ss_pred HHHHHHHCCCEEEEEEECCC----CCCHHHHHCCCEEEEEEEECCCCCEEECCCCCCHHEEEEECCCCC T ss_conf 99999857947999840377----320346634851368771015476353266610100023438995

HHsearch alignment for GI: 254780382 and conserved domain: TIGR01054