First Identification of bla_OXA-51-like in Non-baumannii Acinetobacter spp.

Abstract

bla _OXA-51-like, the intrinsic carbapenemase gene in Acinetobacter baumannii previously found only in this species, was detected in a clinical isolate of Acinetobacter genomic species 13TU. This study aimed to characterize this gene in the isolate. Genomic species identification was confirmed by amplified ribosomal DNA restriction analysis and sequence analysis of 16S-23S ribosomal DNA intergenic spacer, rpoB and recA. The bla _OXA-51-like gene, with an upstream ISAba1 insertion, was plasmid-encoded and the surrounding sequences suggested that its origin was from A. baumannii. Transformation of Acinetobacter genomic species 13TU ATCC 17903 with recombinant plas-mid bearing ISAba1-bla _OXA-51-like from the isolate increased the minimum inhibitory concentrations (MICs) of meropenem and imipenem 256-fold. This is the first reportof bla _OXA-51-like in an organism other than A. baumannii. This plasmid-borne bla _OXA-51-like gene with an upstream ISAba1 insertion confers a high level of carbapenem resistance to Acinetobacter genomic species 13TU

Keywords:

• Acinetobacter baumannii
• non-baumannii Acinetobacter spp
• bla
• OXA-51-like genes