Typing of intimin (eae) genes from enteropathogenic Escherichia coli (EPEC) isolated from children with diarrhoea in Montevideo, Uruguay: identification of two novel intimin variants ({micro}B and {xi}R/{beta}2B)

• Published in: Journal of medical microbiology Vol. 55; no. 9; pp. 1165 - 1174
• Main Authors: Blanco, Miguel, Blanco, Jesus E, Dahbi, Ghizlane, Mora, Azucena, Alonso, Maria Pilar, Varela, Gustavo, Gadea, Maria Pilar, Schelotto, Felipe, Gonzalez, Enrique A, Blanco, Jorge
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.09.2006; Society for General Microbiology
• Subjects: Adhesins, Bacterial - classification; Adhesins, Bacterial - genetics; Antigens, Bacterial - analysis; Bacteriology; Biological and medical sciences; Child; Child, Preschool; Cluster Analysis; Deoxyribonucleases, Type II Site-Specific; DNA Fingerprinting; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Electrophoresis, Gel, Pulsed-Field; Escherichia coli - classification; Escherichia coli - genetics; Escherichia coli - isolation & purification; Escherichia coli Infections - microbiology; Escherichia coli Proteins - classification; Escherichia coli Proteins - genetics; Fundamental and applied biological sciences. Psychology; Genes, Bacterial; Genotype; Humans; Infectious diseases; Medical sciences; Microbiology; Miscellaneous; Molecular Sequence Data; O Antigens - analysis; Phylogeny; Polymorphism, Restriction Fragment Length; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Serotyping; Uruguay; South America; Uruguay; America; Human; Typing; Gene; Microbiology; Escherichia coli; Diarrhea; Digestive diseases; Bacteria; Intestinal disease; Identification; Child; Enterobacteriaceae
• ISSN: 0022-2615; 1473-5644
• DOI: 10.1099/jmm.0.46518-0

1 Laboratorio de Referencia de E. coli (LREC), Departamento de Microbioloxía e Parasitoloxía, Universidade de Santiago de Compostela, 27002 Lugo, Spain 2 Unidade de Microbioloxía Clínica, Complexo Hospitalario Xeral-Calde, 27004 Lugo, Spain 3 Departamento de Bacteriología y Virología, Instituto de Higiene, Facultad de Medicina, Universidad de la República, CP 11600 Montevideo, Uruguay Correspondence Jorge Blanco jba{at}lugo.usc.es Received 11 January 2006 Accepted 11 June 2006 A total of 71 enteropathogenic Escherichia coli (EPEC) strains isolated from children with diarrhoea in Montevideo, Uruguay, were characterized in this study. PCR showed that 57 isolates carried eae and bfp genes (typical EPEC strains), and 14 possessed only the eae gene (atypical EPEC strains). These EPEC strains belonged to 21 O : H serotypes, including eight novel serotypes not previously reported among human EPEC in other studies. However, 72 % belonged to only four serotypes: O55 : H– (six strains), O111 : H2 (13 strains), O111 : H– (14 strains) and O119 : H6 (18 strains). Nine intimin types, namely, 1 (two O142 strains), ß 1 (29 strains, including 13 O111 : H2 and 14 O111 : H–), 1 (three O55 : H– strains), (five strains, including three strains with H40 antigen), (two strains), 1 (one strain), (one strain), µ B (six strains of serotypes O55 : H51 and O55 : H–) and R/ ß 2B (22 strains, including 18 O119 : H6) were detected among the 71 EPEC strains. The authors have identified two novel intimin genes ( µ B and R/ ß 2B) in typical EPEC strains of serotypes O55 : H51/H– and O119 : H6/H–. The complete nucleotide sequences of the novel µ B and R/ ß 2 variant genes were determined. PFGE typing after Xba I DNA digestion was performed on 44 representative EPEC strains. Genomic DNA fingerprinting revealed 44 distinct restriction patterns and the strains were clustered in 12 groups. Only 15 strains clustered in six groups of closely related (similarity >85 %) PFGE patterns, suggesting the prevailing clonal diversity among EPEC strains isolated from children with diarrhoea in Montevideo. Abbreviations: AEEC, attaching and effacing E. coli ; A/E, attaching and effacing; DEC, diarrhoeagenic E. coli ; EPEC, enteropathogenic E. coli ; STEC, Shiga-toxin-producing E. coli ; UPGMA, unweighted pair group method with arithmetic means. The GenBank/EMBL/DDBJ accession numbers for the complete nucleotide sequences of the novel µ B and R/ ß 2B variant intimin genes are AJ705049 and AJ715407, respectively.