Attractant- and disulfide-induced conformational changes in the ligand binding domain of the chemotaxis aspartate receptor: A 19F NMR study

A study involved the measurement of the kinematic values of attractant binding of the ligand region of chemotaxis aspartate receptor. The structural regions involved in attractant-induced conformational change were located. Each subunit of the homodimer revealed six parafluorophenylalanine (4-F-Phe) positions. The dissociation rate constant (k-off approximately equal to 10 cubed per second) was calculated from the association rate constant (K-on approximately equal to 10 to the 9th power meter per second) of the bond between the isolated periplasmic domain and the aspartate.