A molecular dynamics study on the effects of varying temperature and pressure on the water transport through aquaporin-1 membrane system

• Main Author: Ducut, Melsa Rose D.
• Format: text
• Language: English
• Published: Animo Repository 2015
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4829
• Institution: De La Salle University

The main objective of this study was to simulate the permeation of water through cell membranes by using the software called GROMACS. In this study, two models were created. The first one was consisted of 32 DLPC, 32 DOPC, 32 DPPC, 32 DSPC and 6000 water molecules. The second one was composed of 32 DLPC, 32 DOPC, 32 DPPC, 32 DSPC, aquaporin-1 and 6000 water molecules and 12 Cl ions. The effect of varying the temperature, which was varied from 300 K to 410 K, on the bilayer thickness was investigated. Additionally, the effect of varying pressure, which was changed from 7.50 MPa to 15.50 MPa, on the time it would take for 5% of water molecules to move through the lipid bilayer and aquaporin-1 was studied. Results show that the thickness of the lipid bilayer is dependent on temperature as expected, but gradual and abrupt changes were observed at certain temperatures. The lipid bilayer expanded as the temperature ascended, which signifies that spaces between the phospholipids increased because the chemical bonds of the lipids weakened. It was also evident that at very high temperature the lipid bilayer collapsed. Results on varying pressure would indicate that increasing the pressure will decrease the time required for the water molecules to permeate the bilayer. It was also observed that the presence of AQP1 significantly decreased the time needed for the water molecules to pass through the bilayer.