Title
Multiple spectroscopic and theoretical investigation of meso-tetra-(4-pyridyl)porphyrin‑ruthenium(II) complexes in HSA-binding studies. Effect of Zn(II) in protein binding
Author
Otávio Augusto Chaves, Lucas B. Menezes, Bernardo A. Iglesias
Year
2020
Journal
Journal of Molecular Liquids
Abstract
The present work reports the interaction between human serum albumin (HSA) – the main bio-distributor of exogenous and endogenous compounds in the human bloodstream -and two synthetic Ru(II)-porphyrins (4-RuTPyP and 4-ZnRuTPyP), by multiple spectroscopic techniques (steady-state, time-resolved, circular dichroism, synchronous and 3D fluorescence) combined with molecular docking calculations. The interaction between HSA and each Ru(II) derivatives is spontaneous and moderate, being enthalpically and entropically driven. Steady-state and time-resolved fluorescence analysis showed static process as the main fluorescence quenching mechanism (ground-state association). The binding of tetra-ruthenated derivative containing Zn(II) ion caused more perturbation on the secondary structure of the albumin than the free-base porphyrin. Each Ru(II)-porphyrin interacts preferentially in the site III (subdomain IB), mainly via electrostatic and hydrophobic forces, as well as via van der Waals forces for the sample which contain Zn(II) ion.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Inorganic chemistry, Ligand binding, Biochemistry