Synthesis of heterobimetallic complexes: In vitro DNA binding, cleavage and antimicrobial studies

• Published in: Journal of photochemistry and photobiology. B, Biology Biology, 2012-09, Vol.114, p.108-118
• Main Authors: Tabassum, Sartaj, Zaki, Mehvash, Arjmand, Farukh, Ahmad, Iqbal
• Format: Article
• Language: English
• Subjects: 5′-GMP; Anti-Infective Agents - chemical synthesis; Anti-Infective Agents - chemistry; Anti-Infective Agents - pharmacology; anti-infective properties; Antimicrobial activity; Cobalt - chemistry; Coordination Complexes - chemical synthesis; Coordination Complexes - chemistry; Coordination Complexes - pharmacology; Copper - chemistry; CT DNA binding; DNA; DNA - metabolism; DNA Cleavage; electrospray ionization mass spectrometry; fluorescence; Gram-Negative Bacteria - drug effects; Gram-Positive Bacteria - drug effects; indole acetic acid; Indoleacetic Acids - chemistry; nuclear magnetic resonance spectroscopy; Phenanthrolines - chemistry; phosphates; photobiology; photochemistry; Static Electricity
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2012.05.017

[Display omitted] ► New CuII–Sn2IV and CoII–Sn2IV complexes were synthesized and characterized. ► DNA binding studies revealed the electrostatic interaction into the minor groove. ► Complex 5 shows efficient hydrolytic cleavage of pBR322 DNA. ► Complex 5 exhibited significant antimicrobial activity. The monometallic (1–3) and heterobimetallic (4–6) complexes, containing 1,10-phenanthroline and indole-3-acetic acid were synthesized and characterized by spectroscopic (IR, UV–vis, NMR, ESI-MS) and analytical methods. The in vitro DNA binding studies of 5 and 6 with CT DNA were carried out by employing various biophysical methods which reveal strong electrostatic binding via phosphate backbone of DNA helix. The binding constant (K) value as determined from fluorescence experiments of complexes 5 and 6 were calculated to be 4.09×104 and 2.51×104M−1, respectively revealing that complex 5 has greater binding propensity for DNA. To gain further insight into the molecular recognition at the target site, interaction studies of 5 with 5′-GMP were carried out by employing 1H and 31P NMR spectroscopy. Complex 5 exhibited preferential selectively towards the minor groove of pBR322 DNA and efficient cleavage activity via hydrolytic pathway. Furthermore complexes 4–6 exhibited significant antimicrobial activity.