Effect of exposure of bacteria to endotoxin on their susceptibility to the lethal action of normal serum.

Michael, J. Gabriel (National Cancer Institute, Bethesda, Md.), and Maurice Landy. Effect of exposure of bacteria to endotoxin on their susceptibility to the lethal action of normal serum. J. Bacteriol. 82:257-264. 1961.-The uptake of typhoid endotoxin by Escherichia coli and Shigella dysenteriae was investigated with respect to its effect on the susceptibility of these strains to the bactericidal action of serum. The attachment of endotoxin to the organisms was found to be dependent on time, temperature, concentration, and the physiological state of the bacteria. Short exposure leading to the adsorption or incorporation of small amounts of endotoxin enhanced the lethal effect of serum, whereas long periods of exposure leading to the uptake of larger amounts rendered the bacteria relatively resistant.