Intermolecular interactions in dry and rehydrated pure and mixed bilayers of phosphatidylcholine and digalactosyldiacylglycerol: a Fourier transform infrared spectroscopy study.
Glycolipids are an important part of almost all biological membranes. Their effects on membrane structure and their interactions with phospholipids, however, have not been extensively studied so far. We have investigated the phase behavior and intermolecular interactions in dry and rehydrated bilayers made from the phospholipid egg phosphatidylcholine (EPC) and the plant chloroplast glycolipid digalactosyldiacylglycerol (DGDG), or from a mixture (1:1) of these lipids, using Fourier transform infrared spectroscopy. We show that there are extensive interactions between EPC and DGDG in mixed membranes, and also between DGDG molecules in pure DGDG membranes, involving sugar OH groups and C[double bond]O, P[double bond]O, and choline moieties in dry membranes. These interactions persist to a certain degree even after rehydration. We present evidence that these interactions influence the mixing behavior in phosphatidylcholine/DGDG membranes and also the phase behavior of both EPC/DGDG and pure DGDG membranes in the dry state.
Popova
Antoaneta V
AV
Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14424 Potsdam, Germany.
Hincha
Dirk K
DK
D055592:Biophysical Phenomena; D001703:Biophysics; D038983:Galactolipids / Q000737:chemistry*; D006017:Glycolipids; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry; D008563:Membrane Lipids / Q000737:chemistry*; D008567:Membranes, Artificial; D010713:Phosphatidylcholines / Q000737:chemistry*; D010743:Phospholipids; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013696:Temperature; D014867:Water / Q000737:chemistry
D038983:Galactolipids; D006017:Glycolipids; D008051:Lipid Bilayers; D008055:Lipids; D008081:Liposomes; D008563:Membrane Lipids; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D010743:Phospholipids; C007388:digalactosyldiacylglycerol; D014867:Water