Shishido K, Ando T
Biochim Biophys Acta. 1979 Jun 20;563(1):261-5. doi: 10.1016/0005-2787(79)90026-1.
A DNA-relaxing enzyme capable of concerted nicking and closing of DNA backbone bonds has been purified from Haemophilus gallinarum by two chromatographic steps and gel filtration. The enzyme efficiently catalyzes the removal of superhelical turns from a negatively twisted DNA and requires Mg2+ for this activity. Slight removal of superhelical turns from a positively twisted DNA generated by binding of ethidium bromide is found, but only at high enzyme concentrations. The DNA-relaxing activity is inhibited markedly with heat-denatured DNA, whereas native DNA and RNA have almost no affect on this activity.
一种能够协同切割和封闭DNA主链键的DNA松弛酶已通过两步色谱法和凝胶过滤从鸡嗜血杆菌中纯化出来。该酶能有效催化从负超螺旋DNA中去除超螺旋圈数，且此活性需要Mg2+。发现从溴化乙锭结合产生的正超螺旋DNA中能轻微去除超螺旋圈数，但仅在高酶浓度下。热变性DNA能显著抑制DNA松弛活性，而天然DNA和RNA对此活性几乎没有影响。
