Crithidia fasciculata 2 D,L-dithiothreitol 2 DNA topoisomerase 2 DNA topoisomerase I 2 DTT 2 NAD+ 2 PARP 2 Poly(ADP-ribose)polymerase 2 TCA 2 Topo 2 Trichloroacetic acid 2 adenosine 2 article 2 catalysis 2 cell nucleus 2 controlled study 2 enzyme activity 2 enzyme inhibition 2 enzyme isolation 2 enzyme purification 2 gel filtration 2 hypoxanthine 2 molecular dynamics 2 nicotinamide 2 nicotinamide adenine dinucleotide adenosine diphosphate ribosyltransferase 2 nonhuman 2 priority journal 2 theophylline 2 thymidine 2 xanthine 2