Advanced search
Start date
Betweenand


pEO5 Plasmid of Escherichia coli of O26 serogroup: comparative analysis with other plasmids that encode alpha hemolysin in pathogenic E. coli.

Full text
Author(s):
Ylanna Kelner Burgos
Total Authors: 1
Document type: Doctoral Thesis
Press: São Paulo.
Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
Defense date:
Examining board members:
Antonio Fernando Pestana de Castro; Waldir Pereira Elias Junior; Andrea Micke Moreno; Tania Mara Ibelli Vaz; Tomomasa Yano
Advisor: Antonio Fernando Pestana de Castro
Field of knowledge: Biological Sciences - Microbiology
Location: Universidade de São Paulo. Biblioteca do Instituto de Ciências Biomédicas; T-ICB BMM QW4; B957pl
Abstract

The conjugative pEO5 encoding haemolysin in strains of EPEC O26 was investigated for its relationship with EHEC haemolysin-encoding of EHEC O26 and O157 strains. pEO5 was found to be compatible with EHEC virulence plasmids and did not hybridize in Southern blots with pO157, indicating that both plasmids were unrelated. A 9227 bp stretch pEO5 DNA encompassing the entire operon hlyCABD was sequenced and compared for similarity to plasmid and chromosomally inherited hly determinants. The a hly determinant of pEO5 (7252 bp) and its upstream region was most similar to corresponding sequences of pHly152, in particular, the structural a-hlyCABD and hlyR regions. pEO5 and hly of EPEC O26 strains from humans and cattle were very similar for the regions encompassing the structural a-hlyCABD. The major difference found between the hly regions of pHly152 and pEO5 is caused by the IS2 upstream of the hlyC in pHly152. The presence of transposonlike structures at both ends of hly sequence indicates that pEO5 was probably acquired by horizontal gene transfer. (AU)