The targeted incorporation of proteins into the membrane is a vital process for cell maintenance; these membrane proteins ensure the proper functioning of the cell’s metabolism, communication with its environment, and energy supply. Protein-sorting mechanisms ensure that membrane proteins are specifically recognized among thousands of different proteins – and are sent to the membrane, where they’re needed. A team headed by Kärt Denks, a doctoral candidate in Professor Hans-Georg Koch’s working group at the Institute of Biochemistry and Molecular Biology at the University of Freiburg, describes this molecular mechanism in detail in the journal Nature Microbiology, using the gut bacterium Escherichia coli. The researchers showed that the signal recognition particle (SRP), present in all living organisms, identifies correct proteins already during their synthesis.