Polyoxyethyleneglycolalkylether (C mE n, m=12, n=8) can induce a large torocyte-like endovesicle in human erythrocytes. The present study aimed to examine how variations in the molecular structure of C mE n (m=10,12,14,16,18; n=1a-10,23) affect the occurrence of torocyte endovesicles. Our results show that torocytes occur most frequently when m=12,14 and n=8,9. At this molecular configuration the detergents induce inward membrane bending (stomatocytic S 1-S 2 shapes) resulting in the formation of a large membrane invagination. These detergents have a strong membrane perturbing, i.e., haemolytic, effect. Theoretical calculations indicate that a torocyte-shaped inside-out membrane vesicle can be created from a large membrane invagination due to the impact of laterally mobile anisotropic membrane inclusions. Such inclusions may be detergent-membrane component complexes or unanchored integral membrane proteins. It is shown that a nonhomogeneous lateral distribution of anisotropic membrane inclusions may stabilise the torocyte endovesicle shape, characterised by having opposite membranes in the thin central region of the vesicles separated by a certain distance. Tubular, conical or inverted conical isotropic inclusions cannot do so. © 2004 Elsevier B.V. All rights reserved.
Hägerstrand, H., Kralj-Iglič, V., Fošnarič, M., Bobrowska-Hägerstrand, M., Wróbel, A., Mrówczyńska, L., … Iglič, A. (2004). Endovesicle formation and membrane perturbation induced by polyoxyethyleneglycolalkylethers in human erythrocytes. Biochimica et Biophysica Acta - Biomembranes, 1665(1–2), 191–200. https://doi.org/10.1016/j.bbamem.2004.08.010