Separation of inner and outer membranes of Rickettsia prowazeki and characterization of their polypeptide compositions.
Smith, D K
Rickettsia prowazeki were disrupted in a French pressure cell and fractionated into soluble (cytoplasm) and envelope fractions. The envelope contained 25% of the cell protein, with the cytoplasm containing 75%. Upon density gradient centrifugation, the envelope fraction separated into a heavy band (1.23 g/cm3) and a lighter band (1.19 g/cm3). The heavy band had a high content of 2-keto-3-deoxyoctulosonic acid, a marker for bacterial lipopolysaccharide, but had no succinic dehydrogenase, a marker for cytoplasmic membrane activity, and therefore represented outer membrane. The lighter band exhibited a high succinate dehydrogenase activity, and thus contained inner (cytoplasmic) membrane. Outer membrane purified by this method was less than 5% contaiminated by cytoplasmic membrane; however, inner membrane from the gradient was as much as 30% contaminated by outer membrane. The protein composition of each cellular fraction was characterized by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. The outer membrane contained four major proteins, which were also major proteins of the whole cell. The cytoplasmic membrane and soluble cytoplasm exhibited a more complex pattern on gels.
ACESSO AO ARTIGOhttp://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=218381
- Isolation and characterization of outer and inner membranes of Selenomonas ruminantium: lipid compositions.
- Separation and characterization of inner and outer envelope membranes of pea chloroplasts
- Isolation and partial characterization of Borrelia burgdorferi inner and outer membranes by using isopycnic centrifugation.
- Isolation and partial characterization of outer and inner membranes from encapsulated Haemophilus influenzae type b.
- Ultrastructure of the Surface of Rickettsia prowazeki and Rickettsia akari