The nano-mechanics inside helical bacteria
Background: The smallest cell in the world, just 200nm thin, is of helical shape, and under-goes fast shape changes in 3D, corresponding to switching of different states of mechanical energy. Shortening and relaxation of protein chains inside the cell lead to fast body deformations ued for locomotion. Problem: The transfer of energy inside the cell body leading to coordinated switching of the protein chains is hardly understood. Basic locomotion principles invented by nature need to be uncovered on a molecular scale. Approach: Interferometrically measured shape changes reveal deformations and energy changes, which differ under external forces. Kramers rate modelling helps to interpret measured transitions between ground and excited states of mechanical energy |
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Publications
- Roth J, Koch M D, Rohrbach A
Dynamics of a Protein Chain Motor Driving Helical Bacteria under Stress
2018 Biophys J, Band: 114, Nummer: 8, Seiten: 1955 - 1969 - Koch M, A. Rohrbach
How to calibrate an object-adapted optical trap for force sensing and interferometric shape tracking of asymmetric structures
2014 Optics Express, Band: 22, Nummer: 21, Seiten: 25242 - 25257 - Koch M, Rohrbach A
Object adapted optical trapping and shape tracking of energy switching helical bacteria
2012 Nat Photonics, Band: 6, Seiten: 680 - 686 - Speidel M, Friedrich L, Rohrbach A
Interferometric 3D tracking of several particles in a scanning laser focus.
2009 Opt Express, Band: 17, Nummer: 2, Seiten: 1003 - 1015