HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gao, Q. Articles by Craven, B. M. Search for Related Content PubMed PubMed Citation Articles by Gao, Q. Articles by Craven, B. M. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol 27, 1214-1221, Copyright © 1986 by Lipid Research, Inc.

ARTICLES

Conformation of the oleate chains in crystals of cholesteryl oleate at 123 K

Q Gao and BM Craven

At 123 K, crystals of cholesteryl cis-9-octadecenoate (cholesteryl oleate, C45H78O2) are monoclinic, space group P2(1) with unit cell dimensions a = 12.356(2), b = 8.980(3), c = 18.382(2) A, beta = 85.49(2) degrees, and have two molecules in the unit cell. The crystal structure including all H atoms has been determined from 3812 independent X-ray reflections with sin theta/lambda less than 0.61 A-1 and refined to give Rw = 0.08. At 123 K, the crystal structure consists of an antiparallel efficient packing of cholesteryl ring systems to form layers that are very similar to those observed in the room temperature structure. The oleate chains that protrude from these layers have a somewhat different packing arrangement from the room temperature structure because they have undergone a conformational change. At 123 K, the oleate chains are well ordered and are almost fully extended except for a kink at the cis double bond. The oleate chains at 123 K are 1.7 A longer than at 295 K due in part to an uncoiling whereby their helical character is lost. On cooling, there is a substantial change in the unit cell beta-angle from obtuse (93.3 degrees) to acute (85.5 degrees) which involves a shearing motion of 2.5 A between adjacent molecular layers. Cell dimension measurements at 10 temperatures in the range 295 K to 123 K show that much of the change occurs in two narrow ranges centered at 262 K and 215 K.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				J. Yano, K. Sato, F. Kaneko, D. M. Small, and D. R. Kodali Structural analyses of polymorphic transitions of sn -1,3-distearoyl-2-oleoylglycerol (SOS) and sn -1,3-dioleoyl-2-stearoylglycerol (OSO): assessment on steric hindrance of unsaturated and saturated acyl chain interactions J. Lipid Res., January 1, 1999; 40(1): 140 - 151. [Abstract] [Full Text]

				Z.-q. Wang, H.-n. Lin, S. Li, and C.-h. Huang Phase Transition Behavior and Molecular Structures of Monounsaturated Phosphatidylcholines J. Biol. Chem., February 3, 1995; 270(5): 2014 - 2023. [Abstract] [Full Text] [PDF]