Table I. ITC measurements of Hsp70/Hsp90-Tomm34 interactions.

ITC was used to investigate the ATP-dependent interaction between Tomm34 and Hsp70. At 25 °C, we observed only a very small enthalpy change for the interaction; thus we explored the interaction at different temperatures (for ITC plots see supplemental Fig. 1). To compare Tomm34 binding to another chaperone, we also measured the Hsp90α/Tomm34 interaction.

Protein complex	Nucleotide	T	KD	ΔH	ΔS	TΔS	N
		°C	μm	cal mol−1	cal mol−1 K−1	cal mol−1
Hsp70/Tomm34	ATP	5	0.40 ± 0.06	5672 ± 168	49.7	13824	0.43 ± 0.01
Hsp70/Tomm34	ATP	15	0.20 ± 0.05	3625 ± 126	43.3	12477	0.40 ± 0.01
Hsp70/Tomm34a	ATP	25	NAb	NA	NA	NA	NA
Hsp70/Tomm34	ATP	30	0.10 ± 1.40	−1647 ± 146	26.5	8033	0.60 ± 0.04
Hsp90α/Tomm34		25	0.96 ± 0.10	−6392 ± 146	6.1	1819	0.57 ± 0.01

^a It was not possible to analyze the data due to a very small enthalpy change.

^b NA means not applicable.