Table 1.

Summary of SecA partitioning free energies at 37°C. Titration curves from which these data are obtained are provided in Figure 2 and Figure S2.

aLipid	bComposition	cKx ×10−3	dΔGwb 0.1 M KCl	cKx ×10−3	dΔGwb 0.1 M KGlu
E. coli extract	—	325 ± 22	−7.8 ± 0.1	198 ± 21	−7.4 ± 0.1
PC	—	en.o.	en.o.	en.o.	en.o.
PE:PC	50:50	8.5 ± 2.3	−5.2 ± 0.2	9.4 ± 4.1	−5.6 ± 0.3
PE:PG	80:20	305 ± 20	−7.8 ± 0.2	235 ± 22	−7.6 ± 0.1
PE:CL	80:20	347 ± 18	−7.9 ± 0.1	245 ± 20	−7.6 ± 0.1

^aPC, palmitoyloleoylphosphatidylcholine (POPC); PE, palmitolyloleoylphosphatidylethanolamine (POPE); PG, palmitolyloleoylphosphatidylglycerol (POPG); CL, cardiolipin.

^bmole ratio.

^cmole-fraction partition coefficient (see Methods)

^dfree energy of transfer, water to bilayer, kcal mol⁻¹

^enot observable