1st International and 10th National Iranian Conference on Bioinformatics

Home Accepted Papers

Spectroscopic and Molecular Docking Studies of Co(III) Carboxamide Complexes with HSA

Paper ID : 1413-ICB10

Authors:

پریسا رضوانی نیا *¹, احمد امیری², سودابه شکرالهی صورتی³, Aria اریا Tajally⁴

¹نازی اباد ، پارک ۱۷شهریور، خ دولت آبادی، ک اصغرزاده پلاک ۴۴ زنگ دوم

²شیمی معدنی- دانشکده شیمی- دانشگاه تهران

³تهران، خوابگاه متاهل دانشگاه تهران

⁴تهران، دامپزشکی خ صالحی تیرسوم پلاک2 واحد1

Abstract:

The binding of small molecules to Human Serum Albumin (HSA) has been investigated for many years through different spectroscopic techniques to illustrate details of the protein structure and binding mechanism [1,2]. The carboxamide [–C(O)NH–] group, ubiquitous throughout nature in the primary structure of proteins, is an important ligand construction unit for coordination chemists. Metal complexes of carboxamide ligands have paid special attention in biological systems and DNA cleavage. We report here the synthesis, spectroscopic characterization and molecular docking studies of [Co(bpb)(Br)(H2O)], (1) and [Co(bpb)(N3)(H2O)], (2) complexes where bpb2-= N,N'-bis(pyridine-2-carboxamido) benzene dianion. The interaction of 1 and 2 with HSA was investigated under physiological conditions, using fluorescence and circular dichroism techniques. The interaction between the complexes and HSA resulted to fluorescence quenching with a blue shift at λmax of 343 nm. The magnitude of the Kq value for both 1 and 2 complexes (~ 1011 M-1s-1) indicates the static mecnanism for the interaction type. Furthermore, molecular docking analysis by using Vina was done to obtain more information regarding the binding sites between the HSA and complexes. The results demonstrated the presence of strong HSA-complex interactions with the binding affinities of -9.7 kcal/mol and -9.3 kcal/mol for 1 and 2, respectively. However, the H-bonding interactions between H atoms of the axially coordinated water molecule and the oxygen atoms of proline (Pro-447B) and cysteine (Cys-448B) residues, led to the changes in the secondary structure of the protein.

Keywords:

carboxamide; HSA Binding; Molecular Docking; DFT; Circular Dichroism; MTT assay.

Status : Paper Accepted (Poster Presentation)