Biomembranes a teaser - uni-muenchen.deBiomembranes – a teaser • defining the cell (what’s...
9
4/20/2012 1 Do, 16:05-17:35, SoSe 2012 Bert Nickel ([email protected] ) Biomembranes – a teaser • defining the cell (what’s cell, what’s not) • blood cells are able to squeeze through narrow pores • impermeable barriers to ions; allows for build-up of chemical and electrical gradients (battery of the cell, life is non-equilibrium) • the outer cell wall is decorated by macro molecules (sugars), which are the cells ID (who am I – who are you) • the immune system relies on cell-cell contacts between T-cells and cells to be sampled. Signalling involved lipid rearrangements • the lung is a huge surface tension problem moderated by surfactants • membranes are the cables of the nervous system, vesicles are the spark generater
Transcript of Biomembranes a teaser - uni-muenchen.deBiomembranes – a teaser • defining the cell (what’s...
4/20/2012
1
Do, 16:05-17:35, SoSe 2012 Bert Nickel ([email protected])
Biomembranes – a teaser • defining the cell (what’s cell, what’s not)
• blood cells are able to squeeze through narrow pores
• impermeable barriers to ions; allows for build-up of chemical and
electrical gradients (battery of the cell, life is non-equilibrium)
• the outer cell wall is decorated by macro molecules (sugars), which are the cells ID (who am I – who are you)
• the immune system relies on cell-cell contacts between T-cells and cells to be sampled. Signalling involved lipid rearrangements
• the lung is a huge surface tension problem moderated by surfactants
• membranes are the cables of the nervous system, vesicles are the spark generater
4/20/2012
2
membranes wrap everything
blood cells
4/20/2012
3
the impermeable membrane
Walther Nernst 1864 - 1941
sugar coats identify cells
4/20/2012
4
immune system: cell-cell contacts of killer cells
genetic program starts
the lungs: surface tension at work
Pulmonary surfactant is present in the epithelial lining of alveoli. Its main function is to lower the surface tension between air and alveolar fluid and thus to prevent alveolar collapse at end of the expiration (Clements 1977)... Pulmonary surfactant consists of lipids (90–95%) and four surfactant proteins (SP-A, SP-B, SP-C, and SP-D, 5–10%).
4/20/2012
5
neurons and synapses
50nm
why is this physics ?
4/20/2012
6
from simple to complex
identify the essential elements, learn about their interactions
Self assembled monolayers
4/20/2012
7
Molecular crystals and thin films
use whatever experimental tools it needs
Max von Laue 1879 - 1960
today ESRF, a 3rd generation synchrotron
tomorrow: Max-von-Laue symposium
4/20/2012
8
experimental methods covered
• diffraction
• fluorescence microscopy FRET, FCS, FRAP
• light scattering
• patch clamp
• vesicle preparation
• Langmuir trough
• …
theoretical concepts
thermodynamics mechanics, forces
electrochemistry hydration forces
fluctuations random motion, diffusion
4/20/2012
9
http://www.physik.lmu.de/lehre/vorlesungen/sose_12/membranes/index.html
Literature
• Ole G. Moritsen Life - as a matter of fat. The emerging science of lipidomics
• Jacob Israelachvili Intermolecular & surface forces
• Erich Sackmann Einführung in die Biophysik
