>TIGR01059 gyrB DNA gyrase, B subunit; InterPro: IPR011557 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 II topoisomerases are ATP-dependent enzymes, and can be subdivided according to their structure and reaction mechanisms: type IIA (topoisomerase II or gyrase, and topoisomerase IV) and type IIB (topoisomerase VI). These enzymes are responsible for relaxing supercoiled DNA as well as for introducing both negative and positive supercoils . Topoisomerase II (called gyrase in bacteria) primarily introduces negative supercoils into DNA. In bacteria, topoisomerase II consists of two polypeptide subunits, gyrA and gyrB, which form a heterotetramer: (BA)2. In most eukaryotes, topoisomerase II consists of a single polypeptide, where the N- and C-terminal regions correspond to gyrB and gyrA, respectively. This entry represents the B subunit (gyrB) as found predominantly in bacteria, but does not include the topoisomerase II enzymes composed of a single polypeptide, as are found in most eukaryotes. GyrB has two functional domains: an N-terminal ATPase and a C-terminal responsible for subunit interactions, the latter differing between subunit B and single polypeptide topoisomerase II . More information about this protein can be found at Protein of the Month: DNA Topoisomerase .; GO: 0003677 DNA binding, 0003918 DNA topoisomerase (ATP-hydrolyzing) activity, 0005524 ATP binding, 0006265 DNA topological change, 0005694 chromosome.

Probab=98.67 E-value=8.4e-08 Score=75.71 Aligned_cols=269 Identities=15% Similarity=0.300 Sum_probs=160.6 Q ss_pred HHHHHHHHHHHHHH---CC-CCEEEEEEECCCEEEEEEEECCCCCCHH-----H------HH---HH-HCCCCCCCCHHH Q ss_conf 78999999987772---69-9679999980984399999888998898-----9------99---87-502466563124 Q gi|254780399|r 23 PSIAIKELIENSLD---AE-SSRVETVIAGGGKSFFQITDNGFGMTSE-----E------IP---MA-VQRHCTSKISDD 83 (594) Q Consensus 23 ~~svVkELveNSlD---Ag-At~I~v~i~~~g~~~i~V~DnG~Gi~~~-----d------l~---~~-~~rh~TSKi~~d 83 (594) T Consensus 32 LHHlvyEVVDNaIDEAlAGyC~~I~v~i~~dg--sv~V~DnGRGIPVdIHp~eGakqGRe~SA~EvVlT~LHAGGKFD~~ 109 (818) T TIGR01059 32 LHHLVYEVVDNAIDEALAGYCDTINVTINDDG--SVTVEDNGRGIPVDIHPEEGAKQGREISAVEVVLTVLHAGGKFDKD 109 (818) T ss_pred CEEEEEEEECCHHHHHHCCCCCEEEEEEECCC--EEEEEECCCCCCCCCCCCCCCCCCCCCCCEEEEEEEECCCEEECCC T ss_conf 23899998434044200661241489996287--6999858858874306768787888566000122000575001588 Q ss_pred HHHCCCCCCCHHHHHHHHHHE-EEEEEEECCCCCCCEEEEECCCCCCC-C---CCCCCCCCCEEEEEHHHHHHHHHHHCC Q ss_conf 411214884048999876202-48999804898630155110100000-2---110125675788521012112543103 Q gi|254780399|r 84 FSNIHTFGFRGEALPSIGAVS-HLTLMSRPPQNNTGAQIAISGEKISS-V---RPVAMNPGTIVEVRDLFFTIPARLNFL 158 (594) Q Consensus 84 l~~i~t~GFRGEAL~sIa~vs-~l~i~s~~~~~~~~~~~~~~~g~~~~-~---~~~~~~~GT~V~V~~LF~N~PvRrkfl 158 (594) T Consensus 110 sYKV-SGGLHGVGvSVVNALS~~L~v~v~RdGk--~y~q~F~~G~P~~~L~~~G~~~~~~GT~V~-------------F~ 173 (818) T TIGR01059 110 SYKV-SGGLHGVGVSVVNALSEWLEVTVKRDGK--IYRQEFERGIPVGPLEVVGEETKKTGTTVR-------------FV 173 (818) T ss_pred CEEE-ECCEEECCEEEEEECCCEEEEEEEECCE--EEEEEECCCCEECCEEEECCCCCCCCCEEE-------------EE T ss_conf 0478-6756503279996117289999998692--999998487220530681346566676789-------------96 Q ss_pred CCHH-----H--HHHHHHHHHHHHHHCCCCCEEEEEECCCC--EE-EEECCCCCHHHHHHHHHHHH--HHHHHHHHH--- Q ss_conf 4536-----8--99999999999873189974999987983--07-99717881048999997321--666543100--- Q gi|254780399|r 159 KSEQ-----V--ETNLITDVIRRMAIAYPKVSFTFSTIKSN--RY-KMNFQSTNGNFPERISQVIG--EDFINNAVE--- 223 (594) Q Consensus 159 ks~~-----~--e~~~I~~~v~~~aL~~P~V~f~l~~~~~~--~~-~l~~~~~~~~l~~ri~~i~G--~~~~~~l~~--- 223 (594) T Consensus 174 PD~~iF~~~~efd~~~l~~RLrELAFLN~Gv~I~l~D~R~~~~k~~~F~YeG---GI~~fV~YLn~~K~~l~~~ii~ekt 250 (818) T TIGR01059 174 PDPEIFEETTEFDFDILAKRLRELAFLNSGVKISLEDERLGKVKKVEFHYEG---GIKSFVKYLNRNKEPLHEEIIYEKT 250 (818) T ss_pred ECHHHHCCCCEECHHHHHHHHHHHHHHCCCCEEEEEECCCCCCCEEEEEECC---CHHHHHHHHCCCCCCCCCCCCCCCC T ss_conf 0713214430332788999998888718972699987325675203787356---1899999953788224788642343 Q ss_pred -CCCCCE----EEEEEEEECCCCCCCCCCHHHHHHHCCCH-HH--------CHHHHHHHHHHHHH-HCCC-CCCE----- Q ss_conf -224420----36566662161103323206677515210-00--------75888999987554-4279-9980----- Q gi|254780399|r 224 -LNEKSN----EITLQGYTGIPTFNRGNANQFYVFINGRT-VQ--------DKFILSTIRTAYAE-TIPL-GRYP----- 282 (594) Q Consensus 224 -i~~~~~----~~~i~G~is~P~~~r~~~~~q~ifVNgR~-V~--------~~~l~~AI~~aY~~-~l~~-g~~P----- 282 (594) T Consensus 251 t~~g~~~~~~~~i~VE--vAL-Qwnd~Y~e~i~sF~NNI~T~eGGTHl~GFr~aLTr~~n~y~~~~~l~Ki~~~~~l~Ge 327 (818) T TIGR01059 251 TISGEKEDDDGGIEVE--VAL-QWNDGYSENILSFVNNINTREGGTHLEGFRSALTRVINSYAKKNKLLKIESKPNLTGE 327 (818) T ss_pred EEEEEECCCCCEEEEE--EEE-EEECCCCCEEEEEECCCCCCCCCCHHHHHHHHHHHHHHHHHHHCCCCCCCCCCCCCCC T ss_conf 1577751677607999--998-7626855103788567556788611778865789999999973687532445567657 Q ss_pred ------EEEEEEEEEHHHHCCCCCC-----HH-----HHHHHCCHHHHHHHHHHHHHHHHH Q ss_conf ------7999999606571247571-----11-----125535979999999997898875 Q gi|254780399|r 283 ------VVVLLLEIDPRQVDVNVHP-----AK-----SYIRFRNPTIIRNFIIQSIQKAIN 327 (594) Q Consensus 283 ------~~vL~i~i~p~~vDVNVHP-----~K-----~eVrf~de~~i~~~i~~~i~~~L~ 327 (594) T Consensus 328 D~REGLtAViSvKvP--------~PqFEGQTK~KLGNsEVr----~~V~~~v~e~l~~f~e 376 (818) T TIGR01059 328 DIREGLTAVISVKVP--------DPQFEGQTKTKLGNSEVR----SIVESLVYEKLTEFFE 376 (818) T ss_pred CCCCCCEEEEEEECC--------CCCCCCCCCCCCCCCCHH----HHHHHHHHHHHHHHHH T ss_conf 710223899998148--------789788322346464167----7788887999999975

HHsearch alignment for GI: 254780399 and conserved domain: TIGR01059