Complement-mediated killing of susceptible gram-negative bacteria: an elusive mechanism

Exposure of gram-negative bacteria to a source of antibody and complement frequently results in efficient cell killing; this effect follows the deposition of C5b-9 membrane attack complexes onto the bacterial surface. This review examines the molecular and physiological events culminating in C5b-9 deposition and cell death and advances an hypothesis that may account for cytoplasmic-membrane damage following complement-mediated perturbation of the outer membrane.