Q-242. Characterization of Enterobacter sakazakii Isolates from Different Environments

A. Cruz1, E. Salinas1, L. Martínez1, B. Gonzalez2, C. Eslava3, C. Amábile-Cuevas4, I. Rosas1;
1Facultad de Medicina-Ctr. de Ciencias de la Atmósfera, UNAM, Mexico, MEXICO, 2Fisiología Celular, UNAM, Mexico, MEXICO, 3Facultad de Medicina, UNAM, Mexico, MEXICO, 4Fundación Lusara, Mexico, MEXICO.

Enterobacter sakazakii was identified by Farmer in 1980, and is considered an opportunistic pathogen; it was later proposed to be renamed as Cronobacter by Iversen. Objective: Here we characterized 16 isolates identified as Enterobacter sakazakii by an automated method (Vitek) from different environments, 7 from urban dust, 5 from alfalfa sprouts, 1 from an urban lake, 1 from soy milk and 2 from urinary catheters Methods: Additional tests proposed as specific for Cronobacter were also performed (indole production, dulcitol fermentation, malonate utilization and production of acid from methyl-alfa-D-glucoside) in isolates. We also determined antibiotic susceptibility by disk diffusion method. An Enterobacter sakazakii gene, ompA and 16S variable region V1-V3 were PCR-amplified. Biofilm formation was assessed by microplate test crystal violet stained. Cronobacter strains were used as positive control. Results: Our isolates previously identify as Enterobacter sakazakii strains, seem to rather be Cronobacter sakazakii sub malonaticus, Cronobacter genomoespecies 1 and Cronobacter dublinensis among environmental and clinical strains. The antibiotic resistance was mainly to cefazoline. Biofilm assays showed that 36% of strains tested were able to form biofilms at 24 h. Conclusion: Phenotypic characterization allow identification of some species of Cronobacter genero. The biofilm forming ability migth represent a potential health risk that need further investigation.