Stabilizing solubilized membrane proteins by supplementing detergents with lipids
(# 2018 by Francis Haraux)
0
20
40
60
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activity (s -1
)
activity (s -1
)
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0
0
20
40
60
80
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time (min)
time (min)
no PC
1:5 PC
no PC
1:10 PC
1:5 PC
1:10 PC
100 mM HG
50 mM HG
Fig. 2.11 Kinetics of inactivation of the b 6 f complex incubated with high concentrations of detergent
supplemented or not with lipids. The purified complex was incubated with either 50 mM or 100 mM of
Hecameg (HG; CMC % 19.5 mM under the conditions used) containing either no added lipids (◆) or a
molar ratio of egg phosphatidylcholine (PC) to micellar detergent of 1:5 (●) or 1:10 (■). The electron
transfer activity from plastoquinol to plastocyanin was followed as a function of time (This figure was
originally published in Breyton et al. 1997, # The American Society for Biochemistry and Molecular
Biochemistry).
2.4 Why Are Membrane Proteins Unstable in Detergent Solutions?
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