Computational modelling of phospholipids in plasma membranes
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
MPNAT Nanotechnology
Publicerad
2022
Författare
Lanai, Victor
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
The purpose of this project was to investigate if the constituents of phospholipids in plasma membranes affect
how cells interact with graphene (G) and graphene oxide (GO). It has previously been shown that vertically
grown graphene flakes are effective in killing bacteria whilst keeping mammalian cells intact. However, the
mechanism behind this phenomena is not known, and is at the same time difficult to measure experimentally.
Therefore we choose density functional theory as a tool, with the goal to enhance the understanding. This
thesis dives into the plasma membranes of bacterial and mammalian cells, and target different phospholipids
in these membranes. The project started off by creation of a library of single phospholipids. These were put
together into systems of pairs for calculation of bonding between different phospholipids. Further, both a G
and a GO flake were created, and incorporated into the systems with the phospholipid pairs. Analysis of
the interaction energies between these flakes with the phospholipid pairs was performed, both when the flakes
approach the phospholipids, and upon penetration of the membrane. Calculations show that the most abundant
phospholipids in mammalian cells have stronger bonding to each other, compared to bacterial phospholipids.
Further, when the G/GO flakes enter between the phospholipid pairs, the bacterial pair exhibits less repulsive
interactions, and a more stable system with the flakes were found. Therefore, these variables may contribute to
the diverse robustness between bacterial and mammalian cells, and thus, the composition of phospholipids can
be an important factor in explaining the difference in viability between organisms.
Beskrivning
Ämne/nyckelord
Density Functional Theory, Microorganism, Bacteria, Eukaryotes, Mammalian, Graphene, Graphene oxide