AraC-like Transcriptional Activator CuxR Binds c-di-GMP by a PilZ-like Mechanism to Regulate Extracellular Polysaccharide Production

Schaper S, et al., doi: 10.1073/pnas.1702435114, Proc Natl Acad Sci U S A, 2017

This study aims to unravel the structure and mechanism of action of a c-di-GMp responsive AraC-like protein, the CuxR, that plays a role in bacterial biofilm generation. The interaction of c-di-GMP, a bacterial second messenger, with CuxR promotes CuxR dimerization and DNA binding. The binding mode of c-di-GMP to CuxR and PilZ-domain, both with similar topologies, is suggesting convergent evolution. In this work biotinylated c-di-GMP was immobilized on SA biosensors and a dilution series of CuxR was used to measure affinity of c-di-GMP to CuxR (KD=6.7 μM) on a Blitz system. Thereby demonstrating unambiguously the binding of c-di-GMP to CuxR.

Read More