Purification, functional characterization, and cDNA sequencing of mitochondrial porin from Dictyostelium discoideum
| Autor: | Roland Benz, Annette Müller-Taubenberger, G Gerisch, F Lottspeich, H Troll, B Humbel, M Ecke, Dieter Malchow, A Schmid |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Lipid Bilayers
Molecular Sequence Data Fluorescent Antibody Technique Porins Saccharomyces cerevisiae Biochemistry Dictyostelium discoideum Membrane Potentials Complementary DNA Animals Humans Dictyostelium Amino Acid Sequence Cloning Molecular Lipid bilayer Molecular Biology Gene Library Gel electrophoresis B-Lymphocytes Chromatography biology Base Sequence Neurospora crassa Sequence Homology Amino Acid Cell Biology Immunogold labelling DNA biology.organism_classification Chromatography Ion Exchange Transmembrane protein Mitochondria Durapatite Porin Electrophoresis Polyacrylamide Gel Hydroxyapatites Bacterial outer membrane Bacterial Outer Membrane Proteins |
| Zdroj: | Europe PubMed Central Scopus-Elsevier |
| ISSN: | 0021-9258 |
| Popis: | Porin of Dictyostelium discoideum was extracted from mitochondria with Genapol X-80 and was purified by hydroxyapatite and CM-cellulose chromatography. The purified protein displayed a single band of 30 kDa in SDS-polyacrylamide gel electrophoresis. The formation of channels in artificial lipid bilayer membranes defined its function as a channel-forming component. Its average single-channel conductance was 3.9 nanosiemens in 1 M KCl, which suggested that the effective diameter of the channel is approximately 1.7 nm at small transmembrane potentials. The channel displayed a characteristic voltage dependence for potentials higher than 20 mV. It switched to substates of smaller conductance and a selectivity different to that of the open state. The closed state was stabilized at low ionic strength. The cDNA sequence of mitochondrial porin from D. discoideum was determined. It showed little sequence similarities to other known mitochondrial porins. The functional similarity, however, was striking. Localization of the porin in the mitochondrial outer membrane was confirmed by immunogold labeling of cryosections of fixed cells. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|