NTU Undergraduates' research April 2014 - Biosciences | Page 141

Identification of Virulence Genes in Cronobacter Species

Identification of Virulence Genes in Cronobacter
Species
Tifaine Héchard, Stephen J. Forsythe.
School of Science and Technology, Nottingham Trent University, Nottingham, U.K.
April 2014

Abstract
Cronobacter is a foodborne pathogen which can cause serious disease in neonates including meningitis, necrotising
enterocolitis and septicaemia. It is a recently defined genus composed of ten species, only three of them have been
linked with clinical cases; C. malonaticus, C. turicensis and in particular C. sakazakii.
As Cronobacter is composed of species with different features our aim is to understand the factors of pathogenicity of
these species in order to be able to avoid or to treat more efficiently neonatal infection.
In vitro experimentation were done for haemolysis, protease activity, capsule production, siderophores production and
antibiotic resistance in several Cronobacter species. Gene search was proceed on the genome of each of the ten species
to identified potential virulence genes. Many differences were found between species. A unique siderophore was found
in C. sakazakii as well as a β-fimbriae not encoded in other species. Furthermore, indole production was not detected
in vitro in the three pathogenic species; C. malonaticus, C. turicensis and C. sakazakii. Through these phenotypic and
genotypic analysis of one representative strains of each species of Cronobacter we identified several interesting
virulence factors.
Key words: Cronobacter species, haemolysis, siderophore, capsule, protease, virulence factors,
antibiotic resistance.

1
Nottingham Trent University – April 2014