Heterogeneity of enteroaggregative Escherichia coli virulence demonstrated in volunteers.
Enteroaggregative Escherichia coli (EAggEC) are diarrheal pathogens defined by aggregative adherence to HEp-2 cells. In an effort to identify pathogenic EAggEC isolates, four groups of 5 volunteers were fed 1 of 4 different EAggEC strains, each at a dose of 10(10) cfu. Strain 042 caused diarrhea in 3 of 5 adults; 3 other EAggEC isolates (17-2, 34b, and JM221) failed to elicit diarrhea. A gene encoding enterotoxin EAST1 was found in strains 042 and 17-2 but not 34b or JM221; a 108-kDa cytotoxin was expressed in all 4 isolates. All 4 isolates showed a modest degree of gentamicin protection in HEp-2 cells. 17-2, 34b, and JM221 expressed the fimbrial antigen AAF/I; 042 did not express this fimbria as determined by immunogold electron microscopy and genetic probe hybridization.
Department of Medicine, University of Maryland School of Medicine, Baltimore 21201.
J P
JP
Nataro
Y
Y
Deng
S
S
Cookson
A
A
Cravioto
S J
SJ
Savarino
L D
LD
Guers
M M
MM
Levine
C O
CO
Tacket
D001422:Bacterial Adhesion; D003967:Diarrhea / Q000188:drug therapy; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000188:drug therapy; D014644:Genetic Variation; D005839:Gentamicins / Q000627:therapeutic use; D006801:Humans; D010641:Phenotype; D014774:Virulence
D005839:Gentamicins