The biochemical differentiation of <it>Enterobacter sakazakii </it>genotypes

• Main Authors: Waddington Mike, Iversen Carol, Farmer Jim J, Forsythe Stephen J
• Format: Article
• Language: English
• Published: BMC 2006-10-01
• Series: BMC Microbiology
• Online Access: http://www.biomedcentral.com/1471-2180/6/94

<p>Abstract</p> <p>Background</p> <p><it>Enterobacter sakazakii </it>is an emergent pathogen that has been associated with neonatal infections through contaminated powdered infant milk formula. The species was defined by Farmer <it>et al. </it>(1980) who described 15 biogroups according to the biochemical characterization of 57 strains. This present study compares genotypes (DNA cluster groups based on partial 16S rDNA sequence analysis) with the biochemical traits for 189 <it>E. sakazakii </it>strains.</p> <p>Results</p> <p>Analysis of partial 16S rDNA sequences gave 4 well defined phylogenetic groups. Cluster group 1 was composed of the majority of strains (170/189) and included Biogroups 1–5, 7–9, 11, 13 and 14. Cluster 3 corresponded with Biogroup 15 and cluster 4 with Biogroups 6, 10 and 12. Cluster group 2 comprised a new Biogroup 16. For the isolates in this study, the four DNA cluster groups can be distinguished using the inositol, dulcitol and indole tests.</p> <p>Conclusion</p> <p>This study demonstrates an agreement between genotyping (partial 16S rDNA) and biotyping and describes a new biogroup of <it>E. sakazakii</it>.</p>