An evaluation of the contribution of membrane lipids to protection against ultraviolet radiation.
Using dioleoylphosphatidylcholine liposomes incorporating various fatty acids and neutral lipids, we have examined the ability of such lipids to provide protection of Escherichia coli and vesicular stomatitis virus (VSV) against the lethal effect of ultraviolet (254 nm) radiation. While the presence of varying amounts of saturated (palmitic) or polyunsaturated (arachidonic) fatty acids or the lipid antioxidant, alpha-tocopherol, had little effect on killing by ultraviolet radiation, considerable radioprotection was observed with beta-carotene, retinal and vitamin K-1 at final concentrations of 1 mg/ml. In another approach, vesicular stomatitis virus grown under conditions in which its envelope fatty acid composition was substantially modified, showed little change in its sensitivity to inactivation by ultraviolet radiation. The results provide strong evidence for a radioprotective role of certain, relatively rare natural lipid components with conjugated polyene systems, but not of the more ubiquitous and abundant membrane fatty acids.
Anderson
R
R
Department of Microbiology and Infectious Diseases, University of Calgary, Alberta, Canada.
Daya
M
M
Reeve
J
J
D002338:Carotenoids / Q000528:radiation effects; D004926:Escherichia coli / Q000528:radiation effects*; D005227:Fatty Acids / Q000528:radiation effects; D008081:Liposomes / Q000528:radiation effects*; D008563:Membrane Lipids / Q000528:radiation effects*; D010713:Phosphatidylcholines; D011836:Radiation Tolerance; D011837:Radiation-Protective Agents / Q000528:radiation effects*; D014466:Ultraviolet Rays; D014721:Vesicular stomatitis Indiana virus / Q000528:radiation effects*
D005227:Fatty Acids; D008081:Liposomes; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D011837:Radiation-Protective Agents; D002338:Carotenoids; C017251:1,2-oleoylphosphatidylcholine