Document Type
Article
Publication Title
Langmuir
Abstract
Vitamin E (α-tocopherol) and a range of other biological compounds have long been known to promote the HII (inverted hexagonal) phase in lipids. Now, it has been well established that purely hydrophobic lipids such as dodecane promote the HII phase by relieving extensive packing stress. They do so by residing deep within the hydrocarbon core. However, we argue from X-ray diffraction data obtained with 1-palmitoyl-2-oleoylphosphatidylcholine (POPE) and 1,2-dioleoylphosphatidylcholine (DOPE) that α-tocopherol promotes the HII phase by a different mechanism. The OH group on the chromanol moiety of α-tocopherol anchors it near the aqueous interface. This restriction combined with the relatively short length of α-tocopherol (as compared to DOPE and POPE) means that α-tocopherol promotes the HII phase by relieving compressive packing stress. This observation offers new insight into the nature of packing stress and lipid biophysics. With the deeper understanding of packing stress offered by our results, we also explore the role that molecular structure plays in the primary function of vitamin E, which is to prevent the oxidation of polyunsaturated membrane lipids.
First Page
4908
Last Page
4916
DOI
10.1021/acs.langmuir.0c00176
Publication Date
5-12-2020
Recommended Citation
Harper, Paul E.; Cavazos, Andres T.; Kinnun, Jacob J.; and Petrache, Horia I., "Thinking like a chemist or beekeeper" (2020). University Faculty Publications and Creative Works. 124.
https://digitalcommons.calvin.edu/calvin_facultypubs/124