title: Neither adriamycin nor actinomycin D displaces Tb3+ from DNA.
abstract: The decay of fluorescence of Tb3+ bound to DNA was measured in the absence and presence of adriamycin and actinomycin D. The decay for Tb3+ bound to DNA was mainly exponential (lifetime: tau = 0.96 ms). In the presence of adriamycin or actinomycin D, the Tb3+ fluorescence decayed much faster, indicating that excitation energy was transferred from Tb3+ to the drugs. Extrapolation of the decay curves to zero time showed that the number of strongly emitting, DNA-bound terbium ions was not reduced by the presence of adriamycin or actinomycin D. Hence, these drugs do not seem to displace Tb3+ bound to DNA.
mesh_terms: D001667:Binding, Competitive; D004247:DNA / Q000378:metabolism*; D003609:Dactinomycin / Q000378:metabolism*; D004317:Doxorubicin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013725:Terbium / Q000378:metabolism*
chemical_list: D013725:Terbium; D003609:Dactinomycin; D004317:Doxorubicin; D004247:DNA