한 DNA-결합 단백질이 진주조 (Pennisetum typhoides)의 미토콘드리아 DNA로부터 분리되었다. 그 DNA결함 단백질은 negatively supercoiled pBR322 DNA를 open circle DNA를 주산물로, linear DNA와 고분자량 multimer를 부산물로 전환시켰다. 반응은 이가 양이온 ($Mg^{++}$, $Mn^{++}$, $Zn^{++}$, $Co^{++}$)을 필요하였으나 ATP를 필요로 하지 않았다. 효소반응은 고농도의 일가 및 이가 양이온, EDTA, SDS, 그리고 spermidine에 의하여 억제되었다. 이 다기능 효소 (topoisomerase, recombinase)는 박테리아 topoisomerase I과는 달리 사다리 중간물질을 만들지 않으므로 잠정적으로 신종의 topoisomerase로 명명한다.
A DNA-binding protein was isolated from pearl millet (Pennisetum typhoides) mitochondrial DNA. The DNA-binding protein transformed negatively supercoiled pBR322 DNA into an open circle DNA as a major product, and a linear DNA and a high molecular weight multimer as minor products. The reaction was dependent on divalent cations ($Mg^{++}$, $Mn^{++}$, $Zn^{++}$, $Co^{++}$), but was independent of ATP. The enzyme reaction was inhibited by high concentrations of monovalent and divalent cations, EDTA, SDS, and spermidine. The putative multifunctional enzyme is tentatively designated as a new class of topoisomerase, since, unlike the bacterial topoisomerase I. it does not produce the ladder intermediates
