title: Characterization of heat-induced interaction of neutral liposome with lipid membrane of Streptomyces griseus cell.
abstract: The interaction between the neutral 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) liposomes and cell membrane of Streptomyces griseus induced by the heat treatment at specific temperature was investigated, focusing on the internalization of the neutral POPC liposomes with S. griseus cells. In an attempt to clarify the modes of liposome internalization, various kinds of inhibitors of endocytotic pathways were used to treat S. griseus cells. The efficiency of the heat treatment on liposome-cell membrane interactions was finally characterized based on the hydrophobic, electrostatic interactions and hydration effect. In fact, the internalization of the neutral liposomes into these cells was found to show higher rate and greater amount at higher temperatures. The kinetic study showed that the maximum amount of the internalized liposomes was, respectively, 469 x 10(5) and 643 x 10(5) liposomes/cell at 37 and 41 degrees C. The internalization of the neutral liposomes induced by the heat treatment was characterized, implying that the endocytosis occurred. The interactions involving the internalization, adsorption, and fusion of these liposomes with S. griseus cells were mainly contributed by the hydrophobic interaction and the unstable hydrogen bonds caused by the loss of water of surface hydration of cell membrane rather than the electrostatic interaction under the specific heat condition.
authors: Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
authors: Kien Xuan
authors: KX
authors: Ngo
authors: Hiroshi
authors: H
authors: Umakoshi
authors: Toshinori
authors: T
authors: Shimanouchi
authors: Ryoichi
authors: R
authors: Kuboi
mesh_terms: D000327:Adsorption; D004705:Endocytosis; D018869:Heat-Shock Response; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008051:Lipid Bilayers / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D010713:Phosphatidylcholines / Q000378:metabolism; D012235:Rhodamines / Q000378:metabolism; D013055:Spectrophotometry, Infrared; D013194:Staining and Labeling; D013305:Streptomyces griseus / Q000166:cytology* / Q000378:metabolism*; D013499:Surface Properties; D014867:Water
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes; D010713:Phosphatidylcholines; D012235:Rhodamines; D014867:Water; C028694:1-palmitoyl-2-oleoylphosphatidylcholine