Document Detail


The interaction of native calf thymus DNA with Fe(III)-dipyrido[3,2-a:2',3'-c]phenazine.
MedLine Citation:
PMID:  18848728     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The mono and bis dipyrido[3,2-a:2',3'-c]phenazine (dppz) adducts of iron(III) chloride, i.e. [Fe(dppz)]Cl(3) and [Fe(dppz)(2)]Cl(3), have been synthesized and characterized. The interaction of the Fe(III)dppz hydrolyzed aquo complex with native calf thymus DNA has been monitored as a function of the metal complex-DNA molar ratio, by variable temperature UV absorption spectrophotometry, circular dichroism (CD) and fluorescence spectroscopy. The results obtained in solution at various ionic strength values give support for a tight intercalative binding of the Fe(III)dppz cation with DNA. In particular, the appearance of induced CD bands, caused by the addition of Fe(III)dppz, indicate the existence of a rigid metal complex-DNA-binding leading to dominating chiral organization of Fe(III)dppz species within the DNA double helix. The trend of selected CD bands with the molar concentration of Fe(III)dppz emphasizes that the presence of high amounts of metal complex induces also the formation of DNA-Fe(III)dppz supramolecular aggregates in solution. The analysis of fluorescence measurements allowed us to calculate a value of the intercalative binding constant comparable to that obtained by UV spectrophotometric titration. Finally, the temperature dependence of the absorbance at 258nm shows that the metal complex strongly increases the DNA melting temperature already at metal complex-DNA molar ratio equal to 0.25 suggesting that metal complex intercalation effectively hinders DNA denaturation. Overall, the results of the present study point out that the Fe(III)dppz aquo complex has DNA-binding properties analogous to those previously reported for the tris-chelate Fe(II)(phen)(2)dppz complex (phen=1,10-phenantroline).
Authors:
Alessio Terenzi; Giampaolo Barone; Arturo Silvestri; Anna Maria Giuliani; Angela Ruggirello; Vincenzo Turco Liveri
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2008-09-05
Journal Detail:
Title:  Journal of inorganic biochemistry     Volume:  103     ISSN:  1873-3344     ISO Abbreviation:  J. Inorg. Biochem.     Publication Date:  2009 Jan 
Date Detail:
Created Date:  2008-12-01     Completed Date:  2009-09-09     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  7905788     Medline TA:  J Inorg Biochem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1-9     Citation Subset:  IM    
Affiliation:
Dipartimento di Chimica Inorganica e Analitica S Cannizzaro, Università di Palermo, d'Orleans II, Palermo, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Circular Dichroism
DNA / metabolism*
DNA Adducts / chemical synthesis,  chemistry,  metabolism*
Ferric Compounds / chemical synthesis,  chemistry,  metabolism*
Fluorescence
Nucleic Acid Denaturation
Phenazines / chemical synthesis,  chemistry,  metabolism*
Chemical
Reg. No./Substance:
0/DNA Adducts; 0/Ferric Compounds; 0/Phenazines; 0/dipyrido(3,2-a-2',3'-c)phenazine; 9007-49-2/DNA; 91080-16-9/calf thymus DNA

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Quantum chemical studies for oxidation of morpholine by Cytochrome P450.
Next Document:  Evaluation of ChloraPrep (2% chlorhexidine gluconate in 70% isopropyl alcohol) for skin antisepsis i...