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The inner mitochondrial membrane contains ion‐conducting channels similar to those found in bacteria
Author(s) -
Petronilli Valeria,
Szabò Ildiko,
Zoratti Mario
Publication year - 1989
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(89)81513-3
Subject(s) - conductance , membrane potential , membrane , ion channel , biophysics , chemistry , voltage dependent anion channel , polarity (international relations) , transmembrane protein , ion , transmembrane channels , inner mitochondrial membrane , patch clamp , bacterial outer membrane , voltage gated ion channel , biochemistry , biology , physics , escherichia coli , receptor , organic chemistry , gene , cell , condensed matter physics
Patch‐clamp experiments were performed on rat liver mitochondria inner membranes. Application of voltage gradients of either polarity revealed the presence of several different conductances, ranging up to 1.3 nS in symmetrical 150 mM KCl. Evidence is presented that at least those higher than 0.3 nS are substates of the highest conductance channel. Increasing matrix‐side‐positive (unphysiological) transmembrane voltage gradients favored the switch of the 1.3 nS channel to operation in lower conductance states. The size of these conductances, the presence of substates and the channel behavior are strongly reminiscent on one hand of the observations on the membrane of protoplasts from the gram‐positive bacterium Streptococcus faecalis , [Zoratti M. and Petronilli V. (1988) FEBS Lett. 240, 105‐109], and on the other of some properties of previously described channels of mitochondrial origin.