Dataset Information

Development of PCR assays targeting the genes involved in synthesis and assembly of the new Escherichia coli O 174 and O 177 O antigens.

ABSTRACT: Escherichia coli O 174 and O 177 are newly described O serogroups which were reported as human pathogens. Identification of these strains by serotyping has been restricted, as the required sera are not commercially available. In this study, a collection of 13 E. coli O 174 strains and 12 E. coli O 177 strains was studied on the O:H serotypes and virulence markers. The O-antigen gene clusters of E. coli O 174 and O 177 were sequenced, and associated genes were assigned functions on the basis of homology. Two genes, each specific for E. coli O 174 and O 177, were identified. PCR assays based on the O-antigen-specific genes were developed and tested on 25 clinical and environmental isolates of those two serogroups as well as 26 isolates of other O serogroups. As little as 1 pg per mul of chromosomal DNA and as few as 0.1 CFU per g of pork and water samples were detected for either strain. The PCR assays established in this study were shown to be highly sensitive and reliable and could be the method of choice for detection of these two human pathogens from clinical, food, and other environmental samples.

SUBMITTER: Beutin L

PROVIDER: S-EPMC1248525 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Development of PCR assays targeting the genes involved in synthesis and assembly of the new Escherichia coli O 174 and O 177 O antigens.

Beutin Lothar L Kong Qingke Q Feng Lu L Wang Quan Q Krause Gladys G Leomil Luciana L Jin Qi Q Wang Lei L

Journal of clinical microbiology 20051001 10

Escherichia coli O 174 and O 177 are newly described O serogroups which were reported as human pathogens. Identification of these strains by serotyping has been restricted, as the required sera are not commercially available. In this study, a collection of 13 E. coli O 174 strains and 12 E. coli O 177 strains was studied on the O:H serotypes and virulence markers. The O-antigen gene clusters of E. coli O 174 and O 177 were sequenced, and associated genes were assigned functions on the basis of h ...[more]

PMID: 16207976

Similar Datasets

Project description:Operons of the afa family are expressed by pathogenic Escherichia coli strains associated with intestinal and extraintestinal infections in humans and animals. The recently demonstrated heterogeneity of these operons (L. Lalioui, M. Jouve, P. Gounon, and C. Le Bouguénec, Infect. Immun. 67:5048-5059, 1999) was used to develop a new PCR assay for detecting all the operons of the afa family with a single genetic tool. This PCR approach was validated by investigating three collections of human E. coli isolates originating from the stools of infants with diarrhea (88 strains), the urine of patients with pyelonephritis (97 strains), and the blood of cancer patients (115 strains). The results obtained with this single test and those previously obtained with several PCR assays were closely correlated. The AfaE adhesins encoded by the afa operons are variable, particularly with respect to the primary sequence encoded by the afaE gene. The receptor binding specificities have not been determined for all of these adhesins; some recognize the Dr blood group antigen (Afa/Dr(+) adhesins) on the human decay-accelerating factor (DAF) as a receptor, and others (Afa/Dr(-) adhesins) do not. Thus, the afa operons detected in this study were characterized by subtyping the afaE gene using specific PCRs. In addition, the DAF-binding capacities of as-yet-uncharacterized AfaE adhesins were tested by various cellular approaches. The afaE8 subtype (Afa/Dr(-) adhesin) was found to predominate in afa-positive isolates from sepsis patients (75%); it was frequent in afa-positive pyelonephritis E. coli (55.5%) and absent from diarrhea-associated strains. In contrast, Afa/Dr(+) strains (regardless of the afaE subtype) were associated with both diarrhea (100%) and extraintestinal infections (44 and 25% in afa-positive pyelonephritis and sepsis strains, respectively). These data suggest that there is an association between the subtype of AfaE adhesin and the physiological site of the infection caused by afa-positive strains.

Dataset Information

Development of PCR assays targeting the genes involved in synthesis and assembly of the new Escherichia coli O 174 and O 177 O antigens.

Publications

Development of PCR assays targeting the genes involved in synthesis and assembly of the new Escherichia coli O 174 and O 177 O antigens.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets