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Eliminating the roughness in cholesterol's β-face: does it matter?

ABSTRACT: One of the long-standing issues surrounding cholesterol (Chol) relates to its two-faced character. In particular, the consequences of its having a rough β-face and a smooth α-face on its structural influence in cell membranes has remained elusive. In this study, direct comparisons have been made between cholesterol and a "smoothened" analog, DChol (i.e., 18,19-dinorcholesterol) using model membranes and a combination of nearest-neighbor recognition, differential scanning calorimetry, fluorescence, and monolayer measurements. Taken together, these results indicate that subtle differences exist between the interaction of these two sterols with the different states of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Chol has a greater condensing power than DChol, but only slightly so, i.e., on the order of a few tens of calories per mole.

SUBMITTER: Krause MR

PROVIDER: S-EPMC4204922 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Eliminating the roughness in cholesterol's β-face: does it matter?

Krause Martin R MR Wang Minghui M Mydock-McGrane Laurel L Covey Douglas F DF Tejada Emmanuel E Almeida Paulo F PF Regen Steven L SL

Langmuir : the ACS journal of surfaces and colloids 20141010 41

One of the long-standing issues surrounding cholesterol (Chol) relates to its two-faced character. In particular, the consequences of its having a rough β-face and a smooth α-face on its structural influence in cell membranes has remained elusive. In this study, direct comparisons have been made between cholesterol and a "smoothened" analog, DChol (i.e., 18,19-dinorcholesterol) using model membranes and a combination of nearest-neighbor recognition, differential scanning calorimetry, fluorescenc ...[more]

PMID: 25290635

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