OBJECTIVES: To characterize the mechanisms involved in reduced susceptibility to carbapenems in two Enterobacter cloacae clinical isolates. METHODS: Two E. cloacae isolates recovered from different regions in Germany and showing reduced susceptibility to carbapenems were analysed. Susceptibility testing, conjugation, transformation assays, plasmid analysis, sequencing and molecular typing using rep-PCR were performed. RESULTS: The two clinical isolates carried the bla(GIM-1) gene and showed resistance to ertapenem, with variable MIC values of imipenem and meropenem. The isolates were clonally unrelated. The bla(GIM-1) gene was located on self-transferable and non-typeable plasmids. Both isolates harboured distinct plasmids and integron structures containing the bla(GIM-1) gene cassette. Interestingly, one of the two plasmids was able to replicate in Pseudomonas aeruginosa, demonstrating its broad host range. CONCLUSIONS: This is the first identification in E. cloacae of the bla(GIM-1) gene, which is responsible for reduced susceptibility to carbapenems. We showed that this gene, previously identified in P. aeruginosa, was located in a different genetic background in E. cloacae. The bla(GIM-1) gene might spread quite efficiently in Enterobacteriaceae and P. aeruginosa, as it is difficult to detect and in addition is located on conjugative plasmids.
OBJECTIVES: To characterize the mechanisms involved in reduced susceptibility to carbapenems in two Enterobacter cloacae clinical isolates. METHODS: Two E. cloacae isolates recovered from different regions in Germany and showing reduced susceptibility to carbapenems were analysed. Susceptibility testing, conjugation, transformation assays, plasmid analysis, sequencing and molecular typing using rep-PCR were performed. RESULTS: The two clinical isolates carried the bla(GIM-1) gene and showed resistance to ertapenem, with variable MIC values of imipenem and meropenem. The isolates were clonally unrelated. The bla(GIM-1) gene was located on self-transferable and non-typeable plasmids. Both isolates harboured distinct plasmids and integron structures containing the bla(GIM-1) gene cassette. Interestingly, one of the two plasmids was able to replicate in Pseudomonas aeruginosa, demonstrating its broad host range. CONCLUSIONS: This is the first identification in E. cloacae of the bla(GIM-1) gene, which is responsible for reduced susceptibility to carbapenems. We showed that this gene, previously identified in P. aeruginosa, was located in a different genetic background in E. cloacae. The bla(GIM-1) gene might spread quite efficiently in Enterobacteriaceae and P. aeruginosa, as it is difficult to detect and in addition is located on conjugative plasmids.
Authors: Andreas F Wendel; Sofija Ressina; Susanne Kolbe-Busch; Klaus Pfeffer; Colin R MacKenzie Journal: Appl Environ Microbiol Date: 2016-05-31 Impact factor: 4.792
Authors: Andreas F Wendel; Martin Kaase; Ingo B Autenrieth; Silke Peter; Philipp Oberhettinger; Heime Rieber; Klaus Pfeffer; Colin R MacKenzie; Matthias Willmann Journal: Antimicrob Agents Chemother Date: 2017-02-23 Impact factor: 5.191
Authors: Andreas F Wendel; Alexander H B Brodner; Stephan Wydra; Sofija Ressina; Birgit Henrich; Klaus Pfeffer; Mark A Toleman; Colin R Mackenzie Journal: Antimicrob Agents Chemother Date: 2013-07-22 Impact factor: 5.191