Antifungal activity, DNA and lysozyme binding affinity of Pd(II) and Pt(II) complexes bearing N,N-pyridylbenzimidazole ligand

Abstract

The lysozyme- and DNA-binding affinities of the biologically active cisplatin analogues, Pd(II) (1) and Pt(II) (2) complexes of functionalized N,N-pyridylbenzimidazole ligand, are reported. The electronic transitions were studied by time-dependent density functional theory. Complex 1 exhibits interesting antifungal activity against Candida albicans (MIC = 32 μg mL⁻¹; 64 nM) and Cryptococcus neoformans (MIC = 16 μg mL⁻¹, 32 nM). Complex 1 is covalently bound to DNA and lysozyme via the elimination of the chloride ligand(s). When complex 2 interacts with lysozyme, two adduct peaks are observed in the mass spectrum corresponding to binding of Pt(II) ion to lysozyme.

Graphical Abstract

Keywords:

• Antifungal agent
• lysozyme
• Candida albicans
• TDDFT

Acknowledgements

A. Mansour thanks Alexander von Humboldt Foundation for Georg Forster postdoctoral fellowship. Antimicrobial screening was performed by The Community for Antimicrobial Drug Discovery (CO-ADD), funded by the Wellcome Trust (UK) and The University of Queensland (Australia). Thanks also to Dr. Ola Shehab, Cairo University, Faculty of Science, Chemistry Department, Egypt, for the mass spectrometer measurements.

Disclosure statement

No potential conflict of interest was reported by the author.