Photodynamic activity rather than drilling causes membrane damage by a light-powered molecular nanomotor.
J Photochem Photobiol B
; 239: 112633, 2023 Feb.
Article
en En
| MEDLINE
| ID: mdl-36608401
ABSTRACT
The chase toward endowing chemical compounds with machine-like functions mimicking those of biological molecular machineries has yielded a variety of artificial molecular motors (AMMs). Pharmaceutical applications of photoexcited monomolecular unidirectionally-rotating AMMs have been envisioned in view of their ability to permeabilize biological membranes. Nonetheless, the mechanical properties of lipid membranes render the proposed drilling activity of AMMs doubtful. Here, we show that singlet oxygen released by a photoexcited "molecular drill" oxidized unsaturated lipids composing giant unilamellar vesicles. In contrast, giant liposomes built of saturated lipids were inert to AMM photoactuation. The AMM did not mechanically destroy gramicidin A ion channels in planar bilayer lipid membranes but instead photoinactivated them. Sodium azide, a singlet oxygen quencher, reduced both AMM-mediated light-induced dye release from unsaturated large unilamellar vesicles and protected gramicidin A from photoinactivation. Upon additional consideration of the underlying bilayer mechanics, we conclude that AMMs' envisioned therapeutic and pharmaceutical applications rely on their photodynamic activity rather than their nanomechanical drilling abilities.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Oxígeno Singlete
/
Gramicidina
Tipo de estudio:
Etiology_studies
Idioma:
En
Revista:
J Photochem Photobiol B
Asunto de la revista:
BIOLOGIA
Año:
2023
Tipo del documento:
Article
País de afiliación:
Rusia