Investigation of proteins in living bacteria with in-cell NMR experiments

In recent years NMR methods have been developed that enable the observation of proteins insideliving bacterial cells. Because of the sensitivity of the chemical shift to environmental changesthese in-cell NMR experiments can be used to study protein conformation, molecular interaction ordynamics in a protein's natural surrounding. Detection of proteins in the bacterial cytoplasmrelies on labeling of the protein of interest with NMR active isotopes. This review describes differentlabeling techniques based on either uniform (15)N or (13)Clabeling as well as amino acid specific labeling schemes. In addition potential applications of thesein-cell NMR experiments and their limitations are discussed.