OXA-244-producers, the nightmare for clinical microbiology labs: insights into their genomes

Background: OXA-48-producing Enterobacteriaceae have widely disseminated throughout Europe. Different variants have been reported, differing by a few amino acid substitutions or deletions mostly in the region of the β5-β6 loop. OXA-244 is a single point mutant derivative of OXA-48 displaying reduced carbapenemase activity. Here, we report features of OXA-244-producing E. coli that may help clinical laboratories to improve their capacity to detect this OXA-48 like carbapenemase. In addition, we have investigated the genetic background and the genetic relatedness of seven OXA-244producing E. coli isolates from different geographical origins.