Global characterisation of proteins and post-translational modifications

Biological systems are astonishingly adaptable and subject to constant change. Cells and tissue react very quickly to external influences; these dynamic changes are one of the research topics of the Protein Dynamics group.

Biological systems first need to be fundamentally investigated in order to understand the interaction between these dynamic changes and various illnesses (such as cancer, blood clotting or cardiovascular complaints) and to find potential approaches for new therapies. To this end, the group requires reliable, reproducible methods that can identify as many components as possible in such systems.

It is nowadays assumed that there are around 10,000 different proteins in a cell which communicate and interact with each other. Depending on the cell type, the concentrations of these proteins can cover up to 6 orders of magnitude: A cell can contain millions of copies of frequently occurring proteins, such as structural proteins, whilst there may only be 10 to 100 copies of rare proteins. The group therefore not only investigates which proteins occur (qualitative analysis), but also the amounts in which they occur (quantitative analysis). 

For this purpose, the group uses and refines different LC-MS techniques, such as label-free quantification. One of the goals is to perform reliable analyses – even with minute quantities of samples - and to standardise procedures to the extent that the methods can be transferred to clinical use. The development of quality standards is important here: Each step of the analysis - from sample preparation through to data evaluation – must work reliably and in a reproducible manner.