Abstract
Herein, we have investigated the effect of cationic gemini surfactant (hexanediyl-alpha,omega-bis-(N-(2-hydroxyethyl) -N-methylhexadecylammonium bromide), (16-6-16MEA) and its monomeric counterpart (N-(2-hyroxyethyl)-N, N-dimethylhexadecylammonium bromide), (16MEA) on the conformational stability of phospholipase A(2) (PLA(2)). The interaction of gemini surfactant and its monomeric counterpart with PLA(2) was characterized by utilizing steady-state fluorescence, time-resolved fluorescence, CD spectroscopy, and computational methods. The steady-state fluorescence results suggested the involvement of static quenching mechanism which was further supported by time resolved fluorescence measurements. The Stern-Volmer equation was utilized to calculate the value of Stern-Volmer quenching constant K-SV. The stoichiometric binding ratio of PLA(2) with 16MEA and 16-6-16MEA was observed to be 1:1. The far-UV CD spectra for PLA(2) revealed similar alteration in secondary structure, in presence of 16MEA and 16-6-16 MEA, which was further supported by computational methods. (C) 2018 Elsevier B.V. All rights reserved.