First detection of TEM-116 extended-spectrum β-lactamase in a Providencia stuartii isolate from a Tunisian hospital.

PURPOSE

To study the resistance to third-generation cephalosporins in Providencia stuartii strain isolated from hospitalized patient in Tunisia and to identify the responsible genes

MATERIALS AND METHODS

This strain was analysed by PCR and sequencing to identify the genes responsible for the β-lactamase resistance phenotypes. The transferability of the phenotypes was tested by conjugation to Escherichia coli J53. The isoelectric point was determinate by isoelectrofocalisation.

RESULTS

This resistance was carried by a 60 kb plasmid that encoded a β-lactamase with a pI of 5.4. This β-lactamase revealed identity with the blaTEM-1 gene encoding the TEM-1 β-lactamase, except for a replacement of the Val residue at position 84 by Ile, and the Ala residue at position 184 by Val. These two mutations were encountered in TEM-116 β-lactamase.

CONCLUSION

This study demonstrates the first description of TEM-116 in the P. stuartii species in the world and the first one in a Tunisian hospital.