Table 1. Effect of receptor on nucleotide exchange kinetics and equilibria.
Reaction | k assoc (M−1·s−1) | +Rec/–Rec | k dissoc (s−1) | +Rec/–Rec | K eq (M−1) | +Rec/–Rec |
t1 | 5.0×102 | 2.2×10−8 | 2.3×1010 | |||
t2 (+A) | 3.8×102 | 6.4×10−10 | 5.9×1011 | |||
t3(+R) | 1.7×106 | 3.4×103 | 1.9×10−2 | 8.6×105 | 8.9×107 | 3.9×10−3 |
t4(+A,+R) | 2.1×106 | 5.5×103 | 3.2×10−2 | 5.0×107 | 6.6×107 | 1.1×10−4 |
d1 | 3.6×103 | 1.5×10−5 | 2.4×108 | |||
d2(+A) | 6.8×103 | 3.7×10−5 | 1.8×108 | |||
d3(+R) | 2.1×107 | 5.8×103 | 2.8×10−1 | 1.9×104 | 7.5×107 | 3.1×10−1 |
d4(+A,+R) | 1.5×106 | 2.2×102 | 4.7 | 1.3×105 | 3.2×105 | 1.7×10−3 |
Rate constants are log average values from Table S2. “+Rec/–Rec” indicates ratios of parameters for Gq that is bound and not bound to activated receptor. “+R” and “+A” label parameters for Gq bound to receptor or GAP.