Free energy plot of ATPase activity.
ΔH‡ and
TΔS‡ values were taken from
Table 3. Except when indicated
otherwise, ATPase activities were determined in the absence of the uncoupler
CCCP. Filled circle, wild-type PS3 ATP synthase; open
circle, Δ380LQDI383 deletion mutant;
filled square, Δ384IAIL387; open
square, Δ388GMDE391; filled
triangle, Δ392LSD394; open triangle,
Δ381QDIIAIL387; filled diamond, wild-type
PS3 ATP synthase measured in the presence of CCCP. The line is an
isobar for ΔG‡ = 67.6 kJ/mol, corresponding
to the value for the wild-type enzyme (determined in the absence of CCCP).