Table 1.

Comparison of ATPase rates of purified Hsp90 protein with fitness effects.

Mutation	Relative ATPase ratea		Fitness effectb
	− Aha1	+ Aha1
None (WT) c	1.0	7.9	0.0
T22Id	4.5	nd	−0.64
A41Vd	<0.1	nd	−0.42
D79Cc	<0.1	1.0	−0.03
D79Ec	0.5	6.1	−0.06
D79Nc,d	<0.1	<0.1	−1.10
T101Id	0.1	nd	−0.74

^aATPase rate measured at 37 °C with or without the co-chaperone Aha1 normalized to the rate of hydrolysis for wildtype without Aha1.

^bFitness effect observed with limiting expression level of Hsp90 from bulk competitions in this work.

^cATPase measurements of Hsp90 variants generated in this work.

^dATPase measurements from previous work (Prodromou et al., 2002).