Capturing the Structure of the Substrate Bound Condensation Domain

Condensation domains of nonribosomal peptide synthetase machineries have so far escaped detailed structural analysis. In this issue of Cell Chemical Biology, Bloudoff et al. (2016) describe a protein tethering technique that allowed the authors to obtain structural information on the substrate bound state of the first condensation domain from calcium-dependent antibiotic biosynthesis, thus opening a new window into how these important biosynthetic machineries function.