The first phospholipid identified as such in biological tissues was lecithin, or phosphatidylcholine, in the egg yolk, by Theodore Nicolas Gobley, a French chemist and pharmacist, in 1847.
Next, in response to many inflammatory stimuli, such as air pollution, smoking, second-hand smoke, vegetables oils and other exogenous toxins; phospholipase is generated and cleaves this phospholipid, releasing AA as a free fatty acid.
These amides conceptually can be formed from a fatty acid and ethanolamine with the release of a molecule of water, but the known biological synthesis uses a specific phospholipase D to cleave the phospholipid unit from N-acylphosphatidylethanolamines.
Atomic force microscopy experimentation on potato PSI expressed separately from its parent AP has revealed that anionic phospholipid membranes are rearranged by PSI in a similar fashion to that observed with saposin C.