Identification of EPEC and non-EPEC serotypes in the EPEC O serogroups by PCR-RFLP analysis of the fliC gene.
Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the flagellin gene (fliC) was performed in 233 strains of enteropathogenic Escherichia coli (EPEC) O serogroups for determining their flagellar antigen (H) status. The serological detection of flagellin is the basis for the H-codes typing system in E. coli. Thus, it is impossible to serotype nonmotile bacteria (i.e. to assign H-codes). Twenty-eight fliC restriction patterns were obtained for motile (H2, H4, H6, H7, H8, H9, H10, H11, H12, H18, H21, H27, H32, H34, H35, H40 and H51) and nonmotile serotypes (H(-)). Each motile serotype was characterized by one or two fliC specific restriction patterns. The only exception was serogroup O128ab, where a common restriction pattern was found for serotypes O128ab:H2 and O128ab:H35, even after digestion with RsaI, AluI and Sau3AI endonucleases. These two serotypes were, however, discriminated by single strand conformation polymorphism (SSCP) analysis of RsaI restriction fragments. Nonmotile strains showed fliC restriction patterns identical to some known H serotypes. The PCR-RFLP analysis of fliC gene proved to be a useful method for identifying the H variants in motile and nonmotile EPEC O serogroups.
Departamento de Imunologia, Instituto de Ciências Biomédicas da Universidade de São Paulo, Av. Prof. Lineu Prestes 1730, 05508-900 São Paulo, Brazil.
Beatriz A
BA
Botelho
Silvia Y
SY
Bando
Luiz R
LR
Trabulsi
Carlos A
CA
Moreira-Filho
D000595:Amino Acid Sequence; D000942:Antigens, Bacterial / Q000235:genetics; D015373:Bacterial Typing Techniques; D004269:DNA, Bacterial / Q000032:analysis; D015252:Deoxyribonucleases, Type II Site-Specific; D003967:Diarrhea / Q000382:microbiology; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology; D004927:Escherichia coli Infections / Q000382:microbiology; D005408:Flagellin / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational; D017422:Sequence Analysis, DNA; D012703:Serotyping
D000942:Antigens, Bacterial; D004269:DNA, Bacterial; C022863:H antigen; D005408:Flagellin; D015252:Deoxyribonucleases, Type II Site-Specific; C040158:GTAC-specific type II deoxyribonucleases