An Upside Down View of Cholesterol's Condensing Effect: Does Surface Occupancy Play a Role?

Janout, Vaclav
Türkyılmaz, Serhan
Wang, Minghui
Wang, Yao
Manaka, Yuichi
Regen, Steven L.
The condensing action or cholesterol has been compared with that of a structural isomer having its hydroxyl group located at the C-25 position (i.e., 25-OH'), that is, an isomer favoring an "upside down" orientation in lipid membranes. Surface pressure area isotherms of mixed monolayers made from 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DM PC)/cholesterol and DM PC/25-OH' have established that 25-OH' has a weaker condensing effect than cholesterol. Nearest-neighbor recognition measurements in liposomes made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) have also shown that 25-OH' has a weaker condensing effect in the physiologically relevant fluid bilayer state. These findings provide support for surface occupancy playing a role in the condensing action of cholesterol.


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Citation Formats
V. Janout, S. Türkyılmaz, M. Wang, Y. Wang, Y. Manaka, and S. L. Regen, “An Upside Down View of Cholesterol’s Condensing Effect: Does Surface Occupancy Play a Role?,” LANGMUIR, pp. 5316–5318, 2010, Accessed: 00, 2020. [Online]. Available: