Characterization of enterotoxigenic Escherichia coli from diarrhoeal patients in Bangladesh using phenotyping and genetic profiling.
A total of 99 isolates out of 370 colonization factor (CF)-positive, well-characterized enterotoxigenic Escherichia coli (ETEC) strains belonging to 13 different CF types isolated from diarrhoeal patients admitted to the hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, were tested. The isolates were selected at random based on expression of the major CFs prevailing in Dhaka, Bangladesh, from 1996 to 1998. These isolates were characterized by O-antigenic serotyping, randomly amplified polymorphic DNA (RAPD) analysis and biochemical fingerprinting using the PhenePlate (PhP) system. The 99 ETEC isolates belonged to 10 O serogroups, the predominant ones being O6 (n=28), O115 (n=20) and O128 (n=20). Most isolates of serogroup O6 (CS1+CS3, 11/14; CS2+CS3, 5/8) belonged to the same PhP/RAPD type (H/f), whereas other isolates of serogroup O6 (n=12) belonged to different PhP/RAPD types (Si/f and F/c). Eleven serogroup O128 (CFA/I) isolates belonged to the same PhP/RAPD type (E/b), whereas the other O128 isolates formed different PhP/RAPD types. Fifteen (75%) serogroup O115 isolates (together with fourteen isolates from serogroups O25, O114, O142 and O159) demonstrated two closely related common groups by PhP typing (A and A1) and belonged to the same PhP/RAPD type (A/a). Three major clonal groups were identified among the ETEC strains in this study, largely based on O-antigenic type, CF expression pattern and toxin profile.
Ansaruzzaman
M
M
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
Bhuiyan
N A
NA
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
Begum
Y A
YA
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
Kühn
I
I
Microbiology and Tumorbiology Centre, Karolinska Institute, Stockholm, Sweden.
Nair
G B
GB
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
Sack
D A
DA
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
Svennerholm
A-M
AM
Department of Medical Microbiology and Immunology, Goteborg University, S-413 46 Goteborg, Sweden.
Qadri
F
F
ICDDR, B (International Centre for Diarrhoeal Diseases Research, Bangladesh), Centre for Health and Population Research, GPO Box 128, Dhaka-1000, Bangladesh.
D001427:Bacterial Toxins / Q000096:biosynthesis; D015373:Bacterial Typing Techniques; D001459:Bangladesh / Q000453:epidemiology; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D004768:Enterotoxins / Q000096:biosynthesis; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000032:analysis / Q000096:biosynthesis; D036781:Fimbriae Proteins / Q000032:analysis; D006761:Hospitals; D006801:Humans; D017720:Molecular Epidemiology; D019081:O Antigens / Q000032:analysis; D019105:Random Amplified Polymorphic DNA Technique; D012703:Serotyping
D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D019081:O Antigens; C022924:colonization factor antigens; C034151:heat stable toxin (E coli); D036781:Fimbriae Proteins; C027538:heat-labile enterotoxin, E coli