Nona Semana Integrada do Instituto de Física de São Carlos

Using moleculary dynamics to study Langmuir monolayers mimicking pulmonary surfactant

Não agendado

20m

Doutorado

Palestrante

Juan Carlos Burbano Zapata (IFSC - USP)

Descrição

Pulmonary surfactant can be modeled as a phospholipid Langmuir monolayer at the air/water interface.(1) This interaction was studied here using molecular dynamics (MD) simulation, which is a classical computational approach to study systems made of a large number of molecules. This technique is based on the solution of Newton’s equations for all the molecules in the system to predict some of the physical properties. We used the software GROMACS with the Martini force field, based on a four-to-one mapping (2-3) (four heavy atoms are represented by a single interaction center), with 64-128 lipid molecules plus water using two lipid compositions, namely dipalmitoyl phosphatidyl choline (DPPC) and DPPC mixed with palmitoyl oleoyl phosphatidyl choline (POPC), to mimic the properties of lung surfactant. The results show that the differences in lipid composition affect the surface pressure of the monolayer.

Referências

1 DOYLE, R. et al. Molecular dynamics simulations of lung surfactant lipid monolayers. Biophysical Chemistry,v.138, n.3, p.67-77,2008.
2 MARRINK, S. J. et al.The MARTINI force field: Coarse grained model for biomolecular simulations. Journal of Physical Chemisty B, v.111, n.27,p.7812-7824,2007.
3 NIELSEN, S. O. et al. Molecular dynamics investigations of lipid Langmuir monolayers using a Coarse-Grain model. Journal of Physical Chemistry B, v.107, n.50,p.13911-13917,2003.