Factors affecting endotoxin release from the cell surface of avian strains of Pasteurella multocida.
Two avian strains of Pasteurella multocida, a vaccine strain and a virulent field isolate, were investigated to determine their propensity to release endotoxin from the cell surface. Both organisms released comparable amounts of endotoxin when plasma complement proteins were present, however the virulent strain did so without the loss of viability that occurred in the vaccine strain. Blocking complement activity decreased the ability of plasma to elicit endotoxin release from the bacteria. When the cells were treated with divalent metal chelators such as trans-1, 2-diaminocyclohexane-N,N,N1,N1-tetraacetic acid (CDTA), more endotoxin was released from the vaccine strain than from the virulent isolate. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of purified lipopolysaccharide (LPS) from both strains revealed virtually identical patterns. Both had patterns considered typical of rough LPS. Challenge studies in 8 weeks old turkeys showed that the field strain induced endotoxemia of longer duration than the vaccine strain and produced greater mortality.
Lee
M D
MD
Department of Medical Microbiology, College of Veterinary Medicine, University of Georgia, Athens 30602.
Glisson
J R
JR
Wooley
R E
RE
D000818:Animals; D016470:Bacteremia / Q000382:microbiology / Q000662:veterinary; D001428:Bacterial Vaccines; D004731:Endotoxins / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000032:analysis; D016979:Pasteurella multocida / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity; D011201:Poultry Diseases / Q000382:microbiology*; D014422:Turkeys; D014774:Virulence
D001428:Bacterial Vaccines; D004731:Endotoxins; D008070:Lipopolysaccharides