Unit:
Τομέας ΚλινικοεργαστηριακόςLibrary of the School of Health Sciences
Dissertation committee:
Καθηγητής Λεγάκης Νικόλαος, Αναπληρωτής Καθηγητής Χατζηπαναγιώτου Στυλιανός, Αναπληρώτρια Καθηγήτρια Νικολάου Χρυσούλα
Original Title:
Φαινοτυπική και γονοτυπική ανίχνευση λοιμογόνων παραραγόντων σε στελέχη Yersinia enterocolitica που απομονώθηκαν από κλινικά περιστατικά
Translated title:
Identification of phenotypic and genotypic virulence factors in clinical isolates of Yersinia enterocolitica
Summary:
Yersinia enterocolitica is the third most common cause of bacterial enteritis.
The aim of this study was the phenotypic and genotypic characterization of
virulence factors of Y. enterocolitica clinical isolates that were isolated
during the period 2006-2011 from thalassemic children in Greece.
A total of 60 isolates were typed by conventional (serotype - biotype) and
molecular methods (PFGE). Antibiotic resistance phenotypes were also
determined. The pYV plasmid was isolated and the plasmidic (yadA and virF) and
chromosomal (yst) genes associated with virulence of the microorganism, were
identified. Additionally, the pathogenic potential and antibiotic resistance
levels were correlated with the ability of biofilm formation.
All 60 isolates were resistant to ampicillin, cephalothin and
amoxicillin-clavulanate. Fifty-nine isolates were assigned to the pathogenic
bio-serotype O:3/biotype4 and 1 isolate in O:9/biotype2. All isolates were
clonally related as documented by PFGE. Plasmid pYV was identified in 53
isolates. The yadA and virF genes were detected in 54 isolates. All isolates
were proven able to produce biofilm. The presence of the latter structure
dramatically increased antibiotic resistance levels.
In this work various characteristic of Y. enterocolitica isolates endemic in
Greece, have been determined for the first time. Data obtained may facilitate
future studies on Y.enterocolitica virulence.
Keywords:
Virulence factors of Yersinia enterocolitica, Plasmid of yersinia virulence, Yersinia adhesin (yadA), Biofilm formation, Yersinia stable toxin (yst)
Number of references:
175
