Naslov
Phytosphingosine and Sphingosine Ceramide H-bonding: Structural Insights from Thermotropic H-D Exchange

Autori
Moore, David ; Rerek, Mark ; Marković, Berislav ; Vanwyck, Dina ; Garidel, Patrick ; Chen, H. ; Mendelsohn, Richard

Izvornik
BIOPHYSICAL JOURNAL (0006-3495) 82 (2002), 1; 159-160

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, kongresno priopcenje, znanstveni

Ključne riječi
Phytosphingosine

Sažetak
IR spectroscopic studies are reported for phytosphingosine ceramides and their behavior contrasted with sphingosine ceramides. These measurements utilize temperaturecontrolled HATR infrared spectroscopy of hydrated films to study H’ D exchange in the polar regions of the molecules as well as chain conformational and packing properties. Analysis of methylene stretching and scissoring vibrations reveals that the chains of phytosphingosine ceramides are more poorly packed than their sphingosine counterparts, in spite of having order’ disorder transitions some 15-20 degrees higher. This unanticipated relative stability of the phytosphingosines is traced to enhanced headgroup H-bonding interactions manifest by lower Amide I and higher Amide II frequencies. Water penetration of the polar regions was also monitored via the temperature dependence of the Amide II and O-H/N-H stretching intensities as a function of H’ D exchange. These measurements reveal that the relative contributions of chain packing and H-bonding under physiological conditions differ markedly for the phytosphingosines compared to the sphingosines The implications of these molecular structure data for lipid organization in the stratum corneum are briefly discussed.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA