Isolation of Escherichia coli bacteriophages from the stool of pediatric diarrhea patients in Bangladesh.
A 3-week coliphage survey was conducted in stool samples from 140 Bangladeshi children hospitalized with severe diarrhea. On the Escherichia coli indicator strain K803, all but one phage isolate had 170-kb genomes and the morphology of T4 phage. In spot tests, the individual T4-like phages infected up to 27 out of 40 diarrhea-associated E. coli, representing 22 O serotypes and various virulence factors; only five of them were not infected by any of these new phages. A combination of diagnostic PCR based on g32 (DNA binding) and g23 (major capsid protein) and Southern hybridization revealed that half were T-even phages sensu strictu, while the other half were pseudo-T-even or even more distantly related T4-like phages that failed to cross-hybridize with T4 or between each other. Nineteen percent of the acute stool samples yielded T4-like phages, and the prevalence was lower in convalescent stool samples. T4-like phages were also isolated from environmental and sewage water, but with low frequency and low titers. On the enteropathogenic E. coli strain O127:K63, 14% of the patients yielded phage, all of which were members of the phage family Siphoviridae with 50-kb genomes, showing the morphology of Jersey- and beta-4 like phages and narrow lytic patterns on E. coli O serotypes. Three siphovirus types could be differentiated by lack of cross-hybridization. Only a few stool samples were positive on both indicator strains. Phages with closely related restriction patterns and, in the case of T4-like phages, identical g23 gene sequences were isolated from different patients, suggesting epidemiological links between the patients.
Chibani-Chennoufi
Sandra
S
Nestlé Research Center, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland.
Sidoti
Josette
J
Bruttin
Anne
A
Dillmann
Marie-Lise
ML
Kutter
Elizabeth
E
Qadri
Firdausi
F
Sarker
Shafiqul Alam
SA
Brüssow
Harald
H
D017122:Bacteriophage T4 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D001459:Bangladesh / Q000453:epidemiology; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology / Q000821:virology*; D004926:Escherichia coli / Q000145:classification / Q000821:virology*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology; D005243:Feces / Q000821:virology*; D005260:Female; D005618:Fresh Water / Q000821:virology; D006801:Humans; D007223:Infant; D008297:Male; D016133:Polymerase Chain Reaction; D012722:Sewage / Q000821:virology
D004279:DNA, Viral; D012722:Sewage