Device for the Mesurement of Biomolecular-Interactions

• Subject Area: Plant Sciences
• Term: Funded in 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 557506741

Interactions between proteins and the associated dynamics of cellular processes are the basis of all life. These interactions include the interplay between subunits of protein complexes, interactions during assembly, stabilization and maintenance of intact protein complexes as well as interactions between proteins and oligopeptides. In addition, low molecular weight ligands can stabilize or destabilize protein interactions. The characterization and mechanistic analysis of these interactions are the central challenges in modern protein biochemistry research. One of the most important protein complexes of life are the membrane-bound protein complexes of oxygenic photosynthesis. Although groundbreaking insights into the structure and assembly of these complexes have been gained in recent years, e.g. using cryo-electron microscopy, research into the dynamics of de novo biosynthesis and the orchestration of constant turnover is still in its infancy. A prerequisite for analyzing the complex interactions between the subunits of the functional complexes, transient binding assembly factors and low-molecular ligands (inhibitors or effectors) is highly sensitive modern instrumentation. A sensible combination of complementary and orthogonal technologies enables the detection, verification and characterization of interactions as well as the determination of stability and integrity of protein complexes. The method of choice for the detection of biomolecular interactions is the label-free analysis of real-time binding kinetics under physiological conditions. This requirement is met by grating coupled interferometry (GCI), which has a very wide range of applications and opens up the possibility of analyzing kinetics with a fast on- or off-rate very precisely. Isothermal microtitration calorimetry as an orthogonal technique enables the simultaneous determination of other binding parameters such as reaction stoichiometry, enthalpy and entropy in a single experiment. This enables a comprehensive thermodynamic characterization of molecular interactions. In addition, information on the size, stability and integrity of the protein complexes in solution completes the characterization and ensures that intact interaction partners were used. The technique of dynamic multi-angle light scattering will be used for this purpose. The acquisition of a GC interferometer in combination with the supplementary equipment modules enables the establishment of a characterization platform which, in addition to structure elucidation by cryo-electron microscopy, represents the most modern equipment technology for the comprehensive analysis and characterization of protein complexes.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Gerät zur Messung Biomolekularer-Interaktionen
• Instrumentation Group: 3160 Biomolekular-Interaktionssysteme
• Applicant Institution: Universität Rostock
• Leader: Professor Dr. Marc Nowaczyk