TOP3B (Vector pUC, Accession No. BC002432)

Length: 2589 Sequence: atgaagactg tgctcatggt tgctgaaaag ccgtccttgg cacagtcaat tgccaaaatc ctctctagag ggagcctgtc ctcacacaaa gggctgaacg gggcctgctc agtccacgag tacactggga cctttgctgg ccagccagtg cgcttcaaga tgacgtctgt ctgtggtcac gtgatgaccc tggatttcct gggaaaatac aacaaatggg acaaagtgga ccccgcagaa ctgttcagcc aagctcccac ggagaagaaa gaagctaacc ccaagctgaa catggtgaag ttcctgcagg tggagggcag aggctgcgac tacatcgtgc tgtggctgga ctgcgacaag gagggggaga acatctgctt tgaggttctt gatgctgttc tgcccgtcat gaacaaggcc catggtggcg agaagaccgt gttccgggcc aggtttagct ccatcacgga cacagacatc tgtaatgcca tggcctgcct aggcgagcct gaccacaacg aggcgctctc agtggatgct cgccaggagc tggacctgcg aatcggctgt gcattcacca ggtttcagac taaatatttc caggggaaat acggtgattt agacagctct ctcatctcct ttgggccgtg tcagactcca accctgggat tctgtgtgga gagacatgat aaaatccagt ccttcaaacc agagacctac tgggtgctgc aggccaaggt taacactgac aaagacagat ctctcctttt ggactgggac cgagtaagag tgtttgaccg ggagatcgca cagatgtttt taaacatgac aaagctggag aaggaagccc aggtggaggc cacaagcagg aaagaaaagg ccaagcagag gcccctggcc ctgaacactg tggagatgct gcgtgtggcc agctcttctc tgggcatggg gccgcagcat gccatgcaga cggctgagcg gctctacacg caaggctaca tcagctaccc acggacagag accacccact accctgagaa ctttgacctg aagggctctc tgcggcagca ggccaaccac ccctactggg ccaacacggt gaagcggttg ttagcagaag gtatcaaccg cccgcggaaa ggccatgacg ccggcgacca tccccccatc acccccatga agtctgccac agaggccgaa ttagggggtg acgcgtggcg gctctatgag tacatcacca gacacttcat cgccacggtc agccatgact gcaagtacct gcagagcacc atctccttca gaattgggcc cgagctcttc acctgctccg ggaagaccgt cctctcacca ggcttcacgg aggtcatgcc ctggcagagc gtgcccctgg aggagagcct gcccacttgc cagcggggtg atgccttccc tgtgggcgag gtgaagatgc tggagaagca gacgaaccca cccgactacc tgacggaggc cgagctcatc acgctcatgg agaagcatgg catcggcacg gatgccagca tccctgtgca tatcaacaac atctgccagc gcaactatgt cacggtggag agcgggcgcc ggctcaagcc caccaacctc ggcatcgtcc tggtgcacgg ctactataag attgatgcag agctggtgct ccccaccatc cgcagtgcag tggagaagca gctgaacctg atcgcccagg gcaaggccga ctaccgccag gtcctgggcc acaccctgga cgtgttcaag aggaagttcc actactttgt cgactccatt gctggcatgg atgagttgat ggaggtgtct ttctcgcccc tggcggccac aggcaagccc ctctcacgct gtgggaagtg ccaccgcttc atgaagtaca tccaggccaa gccaagccgc ctgcactgct cccactgcga tgagacctac acgctccccc agaacggcac catcaagctc tacaaggagc tccgctgccc tctggatgac ttcgagctgg tcctgtggtc atcaggctct cggggcaaga gctacccgct gtgcccctac tgctacaacc acccaccctt ccgagacatg aagaaaggca tgggctgcaa cgagtgtacg cacccctcct gccagcactc gctgagcatg ctgggcatcg gccagtgcgt ggaatgtgag agcggggtgc tggtgctgga ccccacctcg ggccccaagt ggaaggtggc ctgcaacaag tgcaacgtgg tagcgcactg cttcgagaac gcccaccgcg tgcgggtgtc cgccgacacc tgcagtgtct gtgaggccgc cttgcttgat gtggacttca acaaggccaa gtccccactc ccgggcgatg agacgcagca catgggctgc gtcttttgtg accccgtctt ccaggagctg gtggagctga agcatgcggc ctcctgccac cccatgcacc gcggtggacc agggagaagg cagggtcgag ggcggggccg ggccaggagg ccccctggga agcccaaccc cagacggccc aaggacaaga tgtcagccct ggccgcctac Protein function: Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)- enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand than undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone. Possesses negatively supercoiled DNA relaxing activity. [The UniProt Consortium]