Voltage dependence and ion selectivity of the mitochondrial channel, VDAC, are modified by succinic anhydride.
The mitochondrial protein VDAC forms voltage-dependent anion-selective channels in planar phospholipid membranes. When succinic anhydride was added to these membranes, it virtually eliminated VDAC's voltage-dependence and changed its selectivity from anion to cation. These results were obtained without large changes in open-channel conductance or in energy difference between the open and closed states in the absence of a field. Since succinic anhydride converts amino groups into carboxyl groups, we propose that amino groups are responsible for VDAC's voltage-dependence and anion selectivity. Perhaps the same charges are responsible for both functions.
Doring
C
C
Colombini
M
M
D000818:Animals; D000838:Anions; D007473:Ion Channels / Q000378:metabolism*; D008051:Lipid Bilayers; D008564:Membrane Potentials; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D013025:Glycine max; D013386:Succinates; D013387:Succinic Anhydrides
D000838:Anions; D007473:Ion Channels; D008051:Lipid Bilayers; D013386:Succinates; D013387:Succinic Anhydrides; C031801:succinic anhydride