AI Article Synopsis
- A new method is introduced to extract mitochondrial proteolipids using a chloroform-methanol-water mixture, which separates the proteolipids from phospholipids.
- The purified mitochondrial proteolipids are stable complexes of phospholipids and low molecular weight proteins, which are sensitive to acidic conditions.
- Analysis shows that the phospholipid/protein ratio is about 6, and the composition of the extracted proteolipids matches that of mitochondrial phospholipids, revealing unique nonbilayer structures in reconstituted liposomes.
Article Abstract
A convenient procedure is proposed for extracting mitochondrial proteolipids using a single phase mixture chloroform-methanol-water (1:2:0.8 v/v) with subsequent separation of the phases. The proteolipids were concentrated at the interface between the phases and thus purified from the bulk of the phospholipids. It was found that the mitochondrial proteolipids represent stable complexes of phospholipids with some low molecular weight proteins (M(r) = 7-18 kDa). The latter are destroyed at acid pH values. The phospholipid/protein ratio was found to be equal to 6 (assuming the molecular masses of the proteins and phospholipids to be equal to 10 and 0.8 kDa, respectively). The phospholipid composition of the tightly bound proteolipids thus obtained did not differ from that of the mitochondrial phospholipids. Using 31P-NMR, nonbilayer structures were found to arise from proteolipid reconstitution into multibilayer liposomes.
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