TUD Organische ChemieImmelGraphicsMolArch+AnimationsLipophilicity Pattern of SucroseView or Print (this frame only)View or Print (this frame only)

The Lipophilicity Pattern of Sucrose

S. Immel and F. W. Lichtenthaler, Liebigs Ann. Chem. 1995, 1925-1937.
F. W. Lichtenthaler, S. Immel, and P. Pokinskyj, Liebigs Ann. Chem. 1995, 1938-1947.
F. W. Lichtenthaler and S. Immel, in: Sweet Taste Chemoreception (Eds.: M. Mathlouthi, J. A. Kanters, and G. G. Birch), Elsevier Appl. Science, London/New York, 1993, pp. 21-53.
F. W. Lichtenthaler, S. Immel, and U. Kreis, Starch/Stärke 1991, 43, 121-132.
Conformational analysis of sucrose was carried out using the PIMM force-field[1], yielding the global energy minimum structure shown below. Using the MOLCAD[2] molecular modeling program the contact-surface[3] (roughly equivalent to the solvent-accessible surface) of sucrose was generated. The dotted surface is 'closed' by triangulation over all surface points (yielding a triangle-mesh), and then the molecular lipophilicity pattern[4] of sucrose is mapped onto the closed surface model. Thereby, the relative hydrophobicity of sucrose was translated into a 16 color-code, with blue colors corresponding to the most hydrophilic surface regions, and yellow to the most hydrophobic areas. Texture mapping[5] improves the image quality, before the surface is displayed in a transparent mode to visualize the molecular orientation. These molecular modelings yielded a revised model of how sucrose is incorporated into the hydrophobic cleft of the human sweetness receptor (cf. scheme on the right side).


Sucrose lipophilicity pattern
   Sucrose AH-B-X-model

References
[1]
(a) H. J. Lindner, PIMM88 - Closed Shell PI-SCF-LCAO-MO- Molecular Mechanics Program, Technical University of Darmstadt, 1988. - (b) H. J. Lindner, Tetrahedron 1974, 30, 1127-1132. - (c) A. E. Smith, Ph.D. Thesis, Technical University of Darmstadt, 1989. - (d) A. E. Smith and H. J. Lindner, J. Comput.-Aided Mol. Des. 1991, 5, 235-262.
[2]
(a) J. Brickmann, MOLCAD - MOLecular Computer Aided Design, Technical University of Darmstadt, 1992. The major part of the MOLCAD program is included in the MOLCAD-module of the SYBYL package of TRIPOS Associates, St. Louis, USA. - (b) J. Brickmann and M. Waldherr-Teschner, Labo (Hoppenstedt Verlag, Darmstadt) 1989, 10, 7-14; Informationstechnik (Oldenburg Verlag, Muenchen) 1991, 33, 83-90. - (c) J. Brickmann, J. Chim. Phys. 1992, 89, 1709-1721. - (d) M. Waldherr-Teschner, T. Goetze, W. Heiden, M. Knoblauch, H. Vollhardt, and J. Brickmann, in: Advances in Scientific Visualization (Eds.: F. H. Post, A. J. S. Hin), Springer Verlag, Heidelberg, 1992, pp. 58-67. - (e) J. Brickmann, T. Goetze, W. Heiden, G. Moeckel, S. Reiling, H. Vollhardt, and C.-D. Zachmann, Interactive Visualization of Molecular Scenarios with MOLCAD/SYBYL, in: Data Visualization in Molecular Science - Tools for Insight and Innovation (Ed.: J. E. Bowie), Addison-Wesley Publishing Company Inc., Reading, Mass., 1995, pp. 83-97.
[3]
(a) F. M. Richards, Ann. Rev. Biophys. Bioeng. 1977, 6, 151-176; Carlsberg. Res. Commun. 1979, 44, 47-63. - (b) M. L. Connolly, J. Appl. Cryst. 1983, 16, 548-558; Science 1983, 221, 709-713. (c) B. Lee and F. M. Richards, J. Mol. Biol. 1971, 55, 379-400.
[4]
W. Heiden, G. Moeckel, and J. Brickmann, J. Comput.-Aided Mol. Des. 1993, 7, 503-514.
[5]
M. Teschner, C. Henn, H. Vollhardt, S. Reiling, and J. Brickmann, J. Mol. Graphics 1994, 12, 98-105.

© Copyright PD Dr. S. Immel