ChromoTek GmbH (Munich, Germany) has developed a series of highly sensitive protein-protein-interaction (PPI) assays to screen compounds that resolve the binding of two proteins within cells. The so-called fluorescent two hybrid (F2H®) technology is based on a proprietary cell line that contains a spot-like landing platform where one interaction partner binds. The interacting proteins are tagged with different fluorescent proteins and co-localize to the same spot upon binding. The resulting bright dual fluorescent merge signal is clearly detectable and measurable under the microscope. Disruption of the binding by test substances recreates a single fluorescent spot. For drug discovery campaigns the F2H® platform can be fully automated.

One particular advantage of the F2H® platform is that only those molecules will emerge as possible drug candidates which are taken up into cells and which show little or no cytotoxicity. In addition, due to the standardized binding platform used, it is possible to conduct comparative protein-protein-interaction (PPI) studies.

To date, more than 50 protein-protein-interactions have been successfully reconstructed with the F2H® system. “For example, by tracing the binding of p53 to Mdm2 or Mdm4, known inhibitors of these interactions could be verified and new inhibitors identified” states Dr. Kourosh Zolghadr, Head of R&D at ChromoTek. ChromoTek’s academic partner, Prof. Sir David Lane, calls the F2H® approach a missing link between biochemistry and cell biology. In collaboration with his lab, the F2H® assay was successfully applied for comprehensive (stapled) peptide profiling for activation of p53 (recently published in ACS Chem. Biol. 8 (3): 506-512 (2013)).

ChromoTek not only offers p53:Mdm2 and/or p53:Mdm4 compound screening and profiling services but, owing to the flexibility and versatility of this new technology, develops customized F2H® PPI assays to conduct compound screening services for biotech/pharma partners aiming to increase the efficiency of their drug discovery and validation programs with real time cellular data.

bout ChromoTek GmbH

ChromoTek products set new benchmarks in cellular research. Established in 2008 as a spin-off from Munich’s Ludwig Maximilian University, ChromoTek is located in Martinsried, Germany’s leading biotech cluster.

ChromoTek develops and markets immunological and bioimaging reagents and cellular assays for biomedical research and drug discovery. These include the GFP-Trap® for the rapid pull-down of GFP fusion proteins, GFP- and RFP-Booster for intensifying the fluorescence signal of GFP or RFP fusion proteins, Chromobody® based live cell assays for screening and validation as well as a selection of conventional monoclonal antibodies. About 3,000 customers from all over the world trust in ChromoTek products.