DNA Cleavage Mechanism by Metal complexes of Cu(II), Zn(II), Mn(II) and Co(II) with a Schiff-base Ligand

Abstract

Metal ions and metal complexes are important components of nucleic acid biochemistry, participating both in regulation of gene expression and as therapeutic agents. Four new transition  metal complexes of Cu(II), Ni(II), Co(II) and Zn(II) have been synthesized from a new Schiff base ligand derived from 4-bromo aniline, 2-hydroxy-1-naphthaldehyde. The ligand and its complexes have been characterized by spectral analysis. The in vitro antimicrobial activity of the investigated compounds was tested against the bacteria such as Bacillus subtilis, Escherichia coli and fungi Aspergillus flavus and Aspergillus niger. The data indicate that most of the metal complexes have higher antibacterial activity than the free ligand. DNA cleavage experiments performed on pBR322 DNA using metal complexes in the presence of H₂O₂ showed that all the complexes afford a pronounced DNA cleavage.