ELUCIDATION OF THE INDUCED CHIRALITY OF DANSYLGLYCINE BY ITS INTERACTION WITH HUMAN SERUM ALBUMIN

Author(s)

Aguinaldo Robinson de Souza ^[1] ; Izabelle Amorim Ferreira Boza ^[2] ; Valdecir Farias Ximenes ^[3] ; Maurício Ikeda Yoguin ^[4] ; María-José Dávila-Rodriguez ; Nelson Henrique Morgon ^[6] ; Ignez Caracelli ^[7]

Affiliation

^[1] Universidade Estadual Paulista. Faculdade de Ciências. Departamento de Química - Brasil

^[2] Universidade Estadual Paulista. Faculdade de Ciências. Departamento de Química - Brasil

^[3] Universidade Estadual Paulista. Faculdade de Ciências. Departamento de Química - Brasil

^[4] Universidade Estadual Paulista. Faculdade de Ciências. Departamento de Química - Brasil

^[6] Universidade Estadual de Campinas. Departamento de Fisico-Química - Brasil

^[7] Universidade Federal de São Carlos. Departamento de Física - Brasil

• Document type: Journal article
• Source: Química Nova; v. 42, n. 2, p. 135-142, 2019-02-00.

Abstract

Human serum albumin (HSA) plays an important role in the transport of a wide variety of substances, including compounds with pharmacological properties. The dansylglycine (DanG) is a fluorescent amino acid derivative specific for the site II of HSA. This work aimed to elucidate the induction of chirality in the DanG due to its bonding to the HSA. Theoretical electronic circular dichroism spectra (ECDs) were simulated using the Density Functional Theory (DFT) and the implicit Solvation Model based on Density (SMD). The DanG-HSA complexation resulted in the appearance of a positive ECD spectrum centered at 346 nm. Focusing on the dihedral angles between the -N(CH3)2 group bounded to the naphthalene ring, the potential energy surface (PES) of the DanG was obtained. Analysis of the various conformations obtained revealed that the calculated dihedral angle (150º) is in agreed with the experimental ECD spectrum. In addition, we observed that the nitrogen atom of the -N(CH3)2 group presented the greatest contribution to the HOMO-LUMO transition that gives rise to the n→π* electronic transition involved in the generation of the ECD signal. Molecular docking analysis of the complexation between DanG and HSA revealed a conformation with a dihedral angle similar to that obtained by DFT. (AU)

• FAPESP's process: 16/20549-5 - Development and application of fluorescent probes and probes based on circular dichroism for the interaction studies of ligands with protein, characterization of amyloid proteins and determination of enzymatic activity
• Grantee: Valdecir Farias Ximenes
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/22338-9 - Study of the interaction between drugs and human serum albumin (HSA) based on computer simulation, DFT and TDDFT, experiments of electronic circular dichroism, ECD, and determination of the bond formation constant
• Grantee: Aguinaldo Robinson de Souza
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/50926-0 - INCT 2014: biodiversity and natural products
• Grantee: Vanderlan da Silva Bolzani
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants