Does isoprene protect plant membranes from thermal shock? A molecular dynamics study.
The question of why plants release isoprene when heat stressed has been continuously debated for more than half a century. In this work we use molecular dynamics simulation techniques to directly investigate the interaction between isoprene and a model phospholipid membrane in atomic detail. It is found that isoprene partitions preferentially in the center of the membrane and in a dose dependent manner enhances the order within the membrane without significantly changing the dynamical properties of the system. At a concentration of 20 mol% isoprene (16 isoprene molecules per 64 lipid molecules) the effect of the addition of isoprene on the membrane order is equivalent to a reduction in temperature of 10 K, rising to a reduction of 30 K at 43 mol% isoprene. The significance of the work is that it provides for the first time direct evidence that isoprene stabilizes lipid membranes and reduces the likelihood of a phospholipid membrane undergoing a heat induced phase transition. Furthermore it provides a clear mechanistic picture as to why plants specifically utilize isoprene for this purpose.
Siwko
Magdalena E
ME
Laboratory of Lipids and Liposomes, Institute of Biochemistry and Molecular Biology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
Marrink
Siewert J
SJ
de Vries
Alex H
AH
Kozubek
Arkadiusz
A
Schoot Uiterkamp
Anton J M
AJ
Mark
Alan E
AE
D002070:Butadienes; D002462:Cell Membrane / Q000378:metabolism*; D003198:Computer Simulation; D045782:Hemiterpenes / Q000502:physiology*; D006358:Hot Temperature; D008051:Lipid Bilayers; D008563:Membrane Lipids / Q000378:metabolism*; D008958:Models, Molecular; D010420:Pentanes; D010743:Phospholipids / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*
D002070:Butadienes; D045782:Hemiterpenes; D008051:Lipid Bilayers; D008563:Membrane Lipids; D010420:Pentanes; D010743:Phospholipids; C005059:isoprene