Dynamic Allostery of the Catabolite Activator Protein Revealed by Interatomic Forces
Fig 1
Overview of the CAP structure and allostery.
(A) CAP homo-dimer in the two-liganded state known from X-ray diffraction (PDB id: 1G6N [9]). The first protomer is depicted in white cartoon and the second is in yellow cartoon, the two cAMP are represented as balls. (B) Representation of the important region of CAP, the DNA Binding Domain (DBD) is in green, the Nucleotide Binding Domain (NBD) in blue and hot-spots delineated by FDA are in red, the cAMP is in grey balls. (C) Schematic representation of cAMP binding to CAP and allosteric communications between the two protomers. The DBD is shown in green, the NBD is shown in blue. The first cAMP (orange square) binds with a high affinity, whereas the second cAMP binds with a lower affinity (negative cooperativity). The cAMP binding provokes conformational changes in the DBD allowing DNA binding.