Figure 1

Model describing the species and transitions involved in the time-resolved experiments. a: 5-c-His sGC in the resting state. b: 6-C sGC. c: 5-c-NO sGC, in the activate state. d: 4-c sGC after NO dissociation. e: 5-c-His sGC still in the activated conformation, immediately after His105 rebinding. f: 6-c sGC in the activated state, immediately after NO geminate rebinding. The value adjacent to the letter label is the wavelength of the species. The star at the right bracket in c, d, e denotes the activated state of sGC. The starting species of the kinetic measurements is c. The time constants indicated are those measured and the corresponding rates are given in Table 1. In species d, NO is located within the heme pocket whereas in species e, NO is located in another docking site in the protein.