This work unveils the noncovalent
interactions of a novel series
of finely tuned gemini surfactants (C
m
–E2O–C
m
, m = 12, 14, and 16) with myoglobin (Mb) using multifaceted spectroscopic/voltammetric
and docking techniques. The Mb-binding capacity of these geminis decreased
in the order of C14–E2O–C14 >
C16–E2O–C16 > C12–E2O–C12, following the 1:2 stoichiometry,
as confirmed by the quantitative
evaluation of binding constants via intrinsic fluorescence and cyclic
voltammetry. The binding-induced microenvironmental and conformational
changes of Mb were explored by pyrene/synchronous/three-dimensional
(3-D) fluorescence and absorption spectroscopy. Furthermore, far-
and near-ultraviolet (UV) circular dichroism spectral results depicted
discernible changes in both secondary and tertiary structures of Mb
upon complexation with C
m
–E2O–C
m
. Molecular docking specified the binding
site, and aromatic residues involved in the complexation. These investigations
provide deeper insight into the structure–property relationships
of biomacromolecules, and they will be useful in designing/selecting
appropriate surfactants which, in turn, can facilitate the application
of protein–surfactant mixtures in pharmaceutical, biological,
and industrial fields.