Antimicrobial Activity and DNA/BSA Binding Affinity of Polynuclear Silver(I) Complexes with 1,2-Bis(4-pyridyl)ethane/ethene as Bridging Ligands

Sonja Ž Đurić; Sandra Vojnovic; Tina P Andrejević; Nevena Lj Stevanović; Nada D Savić; Jasmina Nikodinovic-Runic; Biljana Đ Glišić; Miloš I Djuran

doi:10.1155/2020/3812050

Antimicrobial Activity and DNA/BSA Binding Affinity of Polynuclear Silver(I) Complexes with 1,2-Bis(4-pyridyl)ethane/ethene as Bridging Ligands

Bioinorg Chem Appl. 2020 Apr 14:2020:3812050. doi: 10.1155/2020/3812050. eCollection 2020.

Authors

Sonja Ž Đurić¹, Sandra Vojnovic², Tina P Andrejević¹, Nevena Lj Stevanović¹, Nada D Savić^{1

3}, Jasmina Nikodinovic-Runic², Biljana Đ Glišić¹, Miloš I Djuran⁴

Affiliations

¹ University of Kragujevac, Faculty of Science, Department of Chemistry, R. Domanovića 12, 34000 Kragujevac, Serbia.
² Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia.
³ University of Kragujevac, Institute for Information Technologies Kragujevac, Department of Science, Jovana Cvijića bb, 34000 Kragujevac, Serbia.
⁴ Serbian Academy of Sciences and Arts, Knez Mihailova 35, 11000 Belgrade, Serbia.

Abstract

1,2-Bis(4-pyridyl)ethane (bpa) and 1,2-bis(4-pyridyl)ethene (bpe) were used for the synthesis of polynuclear silver(I) complexes, {[Ag(bpa)]NO₃}_n (1), {[Ag(bpa)₂]CF₃SO₃ ^.H₂O}_n (2) and {[Ag(bpe)]CF₃SO₃}_n (3). In complexes 1-3, the corresponding nitrogen-containing heterocycle acts as a bridging ligand between two Ag(I) ions. In vitro antimicrobial activity of these complexes, along with the ligands used for their synthesis, was evaluated against the broad panel of Gram-positive and Gram-negative bacteria and fungi. The silver(I) complexes 1-3 showed selectivity towards Candida spp. and Gram-negative Escherichia coli in comparison to the other investigated bacterial strains, effectively inhibiting the growth of four different Candida species with minimal inhibitory concentrations (MICs) between 2.5 and 25 μg/mL and the growth of E. coli, with MIC value being 12.5 μg/mL. Importantly, complex 2 significantly reduced C. albicans filamentation, an essential process for its pathogenesis. Antiproliferative effect on the normal human lung fibroblast cell line MRC-5 was also evaluated with the aim of determining the therapeutic potential of the complexes 1-3. The interactions of these complexes with calf thymus DNA (ctDNA) and bovine serum albumin (BSA) were studied to evaluate their binding activities towards these biomolecules for possible insights on their mode of action.