Dresden 2017 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

BP: Fachverband Biologische Physik

BP 5: Single Molecule Biophysics

BP 5.3: Talk

Monday, March 20, 2017, 15:45–16:00, HÜL 386

Coiled Coils as Mechanical Building Blocks — Melis Goktas, Patricia Lopez-Garcia, Ruby M. A. Sullan, and •Kerstin G. Blank — Max Planck Institute of Colloids and Interfaces

Coiled coils (CCs) are ubiquitous structural motifs found in many different proteins. They are made of α-helices that self-assemble into helical superstructures such as dimers, trimers and tetramers. CCs are important components of cytoskeletal and extracellular matrix proteins, highlighting their crucial role as mechanical building blocks. Despite their widespread appearance, the general structural determinants that define their molecular mechanical properties in different pulling geometries ('shear' vs. 'unzip') are largely unknown. With the goal of shedding light on the structure-to-mechanics relationship, we are applying AFM-based single molecule force spectroscopy to a set of CCs characterized by differences in CC length and sequence. We show that a 28-amino-acid-long, heterodimeric CC ruptures at a most probable force of >40 pN when loaded in shear geometry, while the rupture force for the unzip geometry is below the detection limit of AFM. In the shear geometry, we observe a clear dependence on CC length and helix propensity, showing that the rupture force of CCs in the shear geometry can be tuned by a number of parameters. Our final goal is to develop a library of CCs for the synthesis of CC-based materials with tunable mechanical properties for applications in tissue engineering.