J Antimicrob

Chemother 2009,63(3):462–468.PubMedCrossRef 51. Black RE, Levine MM, Clements ML, Hughes TP, Blaser MJ: Experimental Campylobacter jejuni infection in humans. J Infect Dis 1988,157(3):472–479.PubMedCrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions SH, BJ, JY, and SR conceived and designed the study. SH carried out Geneticin supplier the experimental work and wrote the manuscript. JY designed the mutant construction. SH, BJ, and SR analyzed and interpreted the data. SR and BJ revised the manuscript critically for important intellectual content. All authors read and approved the final manuscript.”
“Background Cronobacter, formerly known as Enterobacter sakazakii [1], is a bacterial genus containing seven this website species [2, 3] in the family Enterobacteriacae; C. sakazakii, C. malonaticus, C. muytjensii, C. turicensis, C. dublinensis, C. universalis, and C. condimenti. The organism has received a lot of attention recently due to its association with neonatal infections,

especially meningitis, necrotizing enterocolitis, septicaemia and subsequent death [4, 5]. see more These bacteria have been isolated from a wide range of food stuffs [6–8], therefore it is important to be able to detect Cronobacter species in food. For this purpose several diagnostic tests exist. However, most of these tests make no distinction as to the species of the bacteria. Not all Cronobacter species are known to be pathogenic to infants and can cause asymptomatic colonisation. The strict microbiological criteria for the presence of Cronobacter in powdered infant formula (< 1 Cronobacter cell/10 g) for intended age < 6 months [9] means it is of great interest to differentiate between pathogenic and non-pathogenic strains. Although a range of possible virulence features (i.e. ompA, adhesins, iron-uptake mechanisms) have been identified in Cronobacter and reviewed elsewhere [10], their presence does not correspond to clinical symptoms. Therefore, the identification of further discriminating factors would be useful.

Currently, to differentiate between species, it is necessary to sequence either the 16S RNA subunit [11] or the MLST genes [12]; the latter is required for searching the Cronobacter MLST database [12, 13]. There are 178 isolates of Cronobacter recorded in the MLST database [13] at the time of analysis IKBKE (March 2011). Although it is known that type 4 strains (ST 4) are associated with meningitis [14], neither of the above methods is able to differentiate between pathogenic and non-pathogenic strains, they only identify individual species. Moreover, both methods are time consuming compared with the use of biochemical diagnostic test kits which take 4-18 hours to produce results that can easily be interpreted. For this reason we aimed to develop methods for identifying which of the strains in the Cronobacter genus are pathogenic based on data obtained from standard biochemical diagnostic tests.