Effects of High Pressure on Phospholipid Bilayers

Abstract

The response of lipid membranes to changes in external pressure is important for many biological processes, and it can also be exploited for technological applications. In this work, we employ all-atom molecular dynamics simulations to characterize the changes in the physical properties of phospholipid bilayers brought about by high pressure (1000 bar). In particular, we study how the response differs, in relation to different chain unsaturation levels, by comparing monounsaturated 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and biunsaturated dioleoyl-phosphatidylcholine (DOPC) bilayers. Various structural, mechanical, and dynamical features are found to be altered by the pressure increase in both bilayers. Notably, for most properties, including bilayer area and thickness, lipid order parameters, lateral pressure profile, and curvature frustration energy, we observe significantly more pronounced effects for monounsaturated POPC than biunsaturated DOPC. Possible biological implications of the results obtained are discussed, especially in relation to how different lipids can control the structure and function of membrane proteins.

Molecular Dynamics Simulation for Mechanism Elucidation of Food Processing and Safety: State of the Art

“…In addition, pressure could modify the structural, mechanical, and dynamical features of membrane. According to Ding et al (2017), the increasing pressure did not influence the bilayer thickness of DOPC, although pressure effect on monounsaturated POPC was more notable than bi-unsaturated DOPC. Apart from the mentioned observation, the number of water crossing events for POPC and DOPC decreased from 54 ± 8 and 52 ± 8 to 14 ± 2 and 33 ± 3 as pressure increased from 0.1 to 100 MPa, respectively.…”

“…Furthermore, pressure slightly changed the area per POPC molecule, that is, 64.6 ± 0.1 Å 2 at 0.1 MPa and 63.8 ± 0.1 Å 2 at 40 MPa. In water, for both the POPC and DOPC bilayers, the head group orientation did not change significantly in response to the elevated pressure (Ding et al., ), although significant decrease in the area per lipid was shown for both membrane as pressure increased to 100 MPa. In addition, pressure could modify the structural, mechanical, and dynamical features of membrane.…”

“…For instance, the study of a multicomponent chocolate system opened a new way for using MD simulation in complex soft matter foods (Greiner et al, 2014). Apart from above achievements, the effects of pressure and electric field on lipid membrane are also studied through MD simulations, which may help unveiling the underlying processing mechanism for food safety (Ding, Palaiokostas, Shahane, Wang, & Orsi, 2017;Moskovitz & Yang, 2015;Tao et al, 2014).…”

First-principles study of intrinsic phononic thermal transport in monolayer C3N

“…33 It is based on the second-order (harmonic) and third-order (anharmonic) interatomic force constants (IFCs) combined with an iterative self-consistent algorithm to solve the Boltzmann transport equation, and has also successfully predicted the thermal conductivities of many materials. 28,[34][35][36][37][38][39][40] 24 and graphene 40 are used in our calculation. The atomic structures of monolayer C3N and graphene are illustrated in Fig.1.…”

Effects of lipid composition on membrane permeation

“…The effect of different lipids on the mechanical properties and dynamic behaviour of bilayer membranes has been studied extensively in the past using experiments 7,8 , analytical theory 9,10 and molecular dynamics (MD) simulations [11][12][13][14][15][16][17][18][19][20][21][22] . In particular, Ding et al 21 have employed atomistic simulations to quantify the effects of changes in the ratio of lamellar vs. nonlamellar lipids on the physical properties of bilayer membranes.…”