Acyl-coenzyme A organizes laterally in membranes and is recognized specifically by acyl-coenzyme A binding protein.
Long chain acyl-coenzyme A (acyl-CoA) is a biochemically important amphiphilic molecule that is known to partition strongly into membranes by insertion of the acyl chain. At present, microscopically resolved evidence is lacking on how acyl-CoA influences and organizes laterally in membranes. By atomic force microscopy (AFM) imaging of membranes exposed to acyl-CoA in microM concentrations, it is shown that aggregate formation takes place within the membrane upon long-time exposure. It is known that acyl-CoA is bound by acyl-CoA binding protein (ACBP) with high affinity and specificity and that ACBP may bind and desorb membrane-bound acyl-CoA via a partly unknown mechanism. Following incubation with acyl-CoA, it is shown that ACBP is able to reverse the formation of acyl-CoA aggregates and to associate peripherally with acyl-CoA on the membrane surface. Our microscopic results point to the role of ACBP as an intermembrane transporter of acyl-CoA and demonstrate the ability of AFM to reveal the remodelling of membranes by surfactants and proteins.
Cohen Simonsen
A
A
MEMPHYS, Physics Department, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark. adam@memphys.sdu.dk
Bernchou Jensen
U
U
Faergeman
N J
NJ
Knudsen
J
J
Mouritsen
O G
OG
D000214:Acyl Coenzyme A / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D026261:Diazepam Binding Inhibitor / Q000737:chemistry / Q000378:metabolism*; D066298:In Vitro Techniques; D008051:Lipid Bilayers / Q000378:metabolism; D008566:Membranes / Q000378:metabolism; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D010713:Phosphatidylcholines / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
D000214:Acyl Coenzyme A; D026261:Diazepam Binding Inhibitor; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D011994:Recombinant Proteins; C017251:1,2-oleoylphosphatidylcholine