Transfer of preformed terminal C5b-9 complement complexes into the outer membrane of viable gram-negative bacteria: effect on viability and integrity
- 20 February 1990
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 29 (7), 1852-1860
- https://doi.org/10.1021/bi00459a027
Abstract
An efficient fusion system between Gram-negative bacteria and liposomes incorporating detergent-extracted C5b-9 complexes has been developed that allows delivery of preformed terminal complexes to the cell envelope (Tomlinson et al., 1989b). Fusion of Salmonella minnesota Re595 and Escherichia coli 17 with C5b-9-incorporated liposomes resulted in the transfer of 1900 C5b-9 complexes to each target bacterial cell. No loss in viability of bacteria was observed following fusion, even though the deposition of 900 complexes onto the envelope following exposure to lysozyme-free serum effected a greater than 99% loss of viability. Increased sensitivity to antibiotics normally excluded from the cell by an integral outer membrane (OM), as well as the ability of the chromogenic substrate PADAC to gain access to periplasmically located .beta.-lactamase, indicated that transferred C5b-9 complexes functioned as water-filled channels through the OM. A similar conclusion was drawn from measurements demonstrating the uptake by cells of the lipophilic cation tetraphenylphosphonium (bromide), a result further indicating that the membrane potential across the cytoplasmic membrane was maintained following C5b-9 transfer to the OM. Examination of S. minnesota Re595 by electron microscopy revealed no obvious difference between cells exposed to lethal concentrations of lysozyme-free serum and cells following fusion with C5b-9-incorporated liposomes. These data suggest either that there are critical sites in the OM to which liposome-delivered C5b-9 complexes are unable to gain access or that bacterial cell death is related to events occurring during polymerization of C9 on the cell surface.This publication has 56 references indexed in Scilit:
- Assembly of complement components C5b-8 and C5b-9 on lipid bilayer membranes: visualization by freeze-etch electron microscopyBiochemistry, 1989
- Complement-mediated killing of Escherichia coli: dissipation of membrane potential by a C9-derived peptideBiochemistry, 1986
- Interaction of human complement proteins with serum-sensitive and serum-resistant strains of Escherichia coliMolecular Immunology, 1984
- Molecular architecture and functioning of the outer membrane of Escherichia coli and other gram-negative bacteriaBiochimica et Biophysica Acta (BBA) - Reviews on Biomembranes, 1983
- Terminal membrane C5b-9 complex of human complement: transition from an amphiphilic to a hydrophilic state through binding of the S protein from serum.The Journal of cell biology, 1982
- Interaction of divalent cations and polymyxin B with lipopolysaccharideBiochemistry, 1979
- C5b-9 dimer: isolation from complement lysed cells and ultrastructural identification with complement-dependent membrane lesions.The Journal of Experimental Medicine, 1979
- Mechanisms of active transport in isolated bacterial membrane vesicles. 28. Membrane potential and active transport in membrane vesicles from Escherichia coliBiochemistry, 1975
- Calcium-dependent bacteriophage DNA infectionJournal of Molecular Biology, 1970
- Areas of Adhesion between Wall and Membrane of Escherichia coliJournal of General Microbiology, 1968