[A DNA topoisomerase from trypanosomes able to catenate, decatenate and unknot DNA without ATP].
A novel DNA-topoisomerase from Trypanosoma cruzi was partially purified. The enzyme, without ATP addition, catalyzes decatenation of kinetoplast DNA, catenation of circular supercoiled DNAs and unknotting of P4 phage DNA. The presence of Mg++ is required as well as a suitable concentration of KCl. In stoichiometric conditions the trypanosome enzyme induces double-strand DNA cleavage. The reaction is highly stimulated by some chemicals. Such characteristics allow to include this enzyme into the type II class of DNA-topoisomerases.
D000255:Adenosine Triphosphate; D000818:Animals; D004247:DNA / Q000378:metabolism*; D004264:DNA Topoisomerases, Type I / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D014349:Trypanosoma cruzi / Q000201:enzymology*
D000255:Adenosine Triphosphate; D004247:DNA; D004264:DNA Topoisomerases, Type I
Une ADN-topoisomérase de trypanosome capable de caténer, décaténer et dénouer l'ADN sans ATP.