Characterization of classic and atypical serogroup O:11 Aeromonas: evidence that the surface array protein is not directly involved in mouse pathogenicity.
A number of different techniques were used to analyse classic and atypical serogroup O:11 Aeromonas isolates. Five of seven atypical O:11, S layer-negative strains lacking a homogeneous LPS side-chain pattern exhibited varying degrees of mouse pathogenecity. One virulent atypical strain (AH-77) synthesized a surface array protein (SAP) but was unable to anchor it to the cell surface in an intact form, presumably due to a defect in its LPS architecture. Proteinase K digestion to remove the SAP, or growth at elevated temperatures (42 degrees C) to reduce the proportion of SAP synthesized from classic O:11 S layer-positive strains, did not alter their LD50 values in outbred mice. In addition, a spontaneous mutant, AS-180-1, that was S layer-negative was as virulent as the parental S layer-positive strain in the mouse model. These results suggest neither the SAP nor the characteristic serogroup O:11 homogeneous LPS side-chain pattern are directly involved in mouse pathogenicity.
Kokka
R P
RP
Microbial Diseases Laboratory, California Department of Health Services, Berkeley 94704.
Vedros
N A
NA
Janda
J M
JM
D000333:Aeromonas / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D000372:Agglutination Tests; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D001426:Bacterial Proteins; D004591:Electrophoresis, Polyacrylamide Gel; D019286:Endopeptidase K; D015151:Immunoblotting; D008070:Lipopolysaccharides / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D010641:Phenotype; D012697:Serine Endopeptidases / Q000378:metabolism; D012703:Serotyping; D013696:Temperature
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; C055764:S-layer proteins; D012697:Serine Endopeptidases; D019286:Endopeptidase K