More than 250 different glycero-phospholipid and sphingomyelin molecular
species make up the structural backbone of the red cell lipid bilayer.
While the overall composition and organization is well maintained during
the life of the cell, this is a very dynamic system in which lipid molecules
are continuously renewed and rapidly move in the plane, and across the
bilayer. To better understand the underlying mechanisms that keep this
dynamic integrity intact are important to assess the consequences of alterations
of this structure to red cell pathology. Whereas the red cell lacks de
novo lipid synthesis, the phospholipids in the plasma membrane are continuously
renewed by a deacylation/reacylation mechanism (the Lands pathway).
||Reacylation of lysophospholipid
Fatty acids (FA) are taken up from the plasma, and moved to the inner
monolayer of the red cell membrane, where Coenzyme A (CoA) is synthesized
by Long acyl CoA synthase (LACS) using ATP. The formed, activated
fatty acyl-CoA (FA-CoA) and lysophospholipid (LPL) is used by lysophospholipid
acylCoA- acyltransferase (LAT) to form phospholipid (PL), releasing
CoA for the next activation of a fatty acid.