Biometals
Cancro, 3-years Fellowship for Italy Project Code: 18044).
CIRCMSB is also acknowledged.
PtBr2(NH3)2 occurs through progressive release of the
two bromide ligands.
When tested with a model protein (lysozyme) a
platination pattern similar to cisplatin emerged, with
protein coordination of [cisPt(NH3)2]2? fragments.
Even the process of platination of standard ctDNA
(800 bp) was highly reminiscent of that of cisplatin
and CD spectroscopy clearly proved the similar nature
of those interactions. One equivalent of ligand (per
base pair, 0.5 equiv per base) turned out to achieve full
binding. The binding is similar for cis-PtBr2(NH3)2
and cisplatin. Using our fragmented ctDNA, the
effects of cisplatin are slightly different from those
reported in the literature for non-sonicated ctDNA
(Tamburro et al. 1977; Sristava et al. 1978).
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Acknowledgments We gratefully acknowledge Beneficentia
Stiftung, Ente Cassa Risparmio Firenze (ECR), COST Action
J
Biol Chem
`
CM1105 and Universita di Pisa (PRA2015-0055) for financial
support, CISM (University of Florence) for recording ESI–MS
spectra, and Dr. Tarita Biver for a sample of fragmented ctDNA.
T.M. thanks AIRC-FIRC (Fondazione Italiana per la Ricerca sul
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