Fluorescence spectroscopic and dynamics simulation studies on isoorientin binding with human serum albumin

Author(s)

Caruso, Icaro Putinhon ^{[1, 2, 3]} ; Vilegas, Wagner ^[4] ; de Oliveira, Leandro Cristante ^[1] ; Cornelio, Marinonio Lopes ^[1]

Affiliation

^[1] UNESP, Inst Biociencias Letras & Ciencias Exatas IBILCE, Dept Fis, Rua Cristovao Colombo 2265, BR-15054000 Sao Jose Do Rio Preto, SP - Brazil

^[2] Univ Fed Rio de Janeiro, Inst Bioquim Media, Ctr Nacl Ressonancia Magnet Nucl & Macromol, BR-21941590 Rio de Janeiro, RJ - Brazil

^[3] Univ Fed Rio de Janeiro, Ctr Nacl Biol Estrutural & Bioimagem CENABIO, BR-21941590 Rio de Janeiro, RJ - Brazil

^[4] UNESP, Inst Biociencias, LBPN, Praca Infante Dom Henrique, BR-11380972 Sao Vicente, SP - Brazil

• Document type: Journal article
• Source: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 228, MAR 5 2020.
• Web of Science Citations: 4

Abstract

Isoorientin (ISOO) a glycosylated flavonoid found in acai berry exhibits relevant activities such as antidiabetic and antidepressant. However, its physicochemical action on any molecular target is scarcely known. In this work, we tackle the problem about the binding of ISOO to human serum albumin (HSA) applying fluorescence spectroscopy bimodal analysis aided by computational simulations. A static quenching process was detected having hypsochromic shift with implication in the polarizability around the endogenous probe (Trp 214) during complex formation. The binding mechanism reveals that all sites are equivalents and independents with binding constant value of 9.1 x 10(4) M-1 and, a total of six sites accessed whereas three of them were identified experimentally. The thermodynamic evaluation indicates that the complex formation is spontaneous (Delta G<0). The dynamics and docking simulations corroborated the experimental data by adding details of each site and its respective microenvironment. (C) 2019 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 17/08834-9 - Experimental and computational assays on molecular targets with pharmacological importance and interactions with natural products
• Grantee: Marinônio Lopes Cornélio
• Support Opportunities: Regular Research Grants