Multilocus sequence typing of Acinetobacter baumanni strains and the distribution of blaOXA-51-like genes in those isolates in Guangzhou / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the distribution of blaOXA-51-like genes and the clonal relation-ship among Acinetobacter baumannii strains isolated from three teaching hospitals in Guangzhou , China. Methods Fifty-two Acinetobacter baumannii isolates were genotyped by multilocus sequence typing (MLST).eBURST algorithm was performed to define clonal complexes (CCs).blaOXA-51-like genes were am-plified by using polymerase chain reaction ( PCR) and sequenced .Results MLST grouped the A.bauman-nii isolates into 5 existing sequence types (STs) and 7 new STs.STn4 carried allele G1 with a T→C muta-tion at the 3rd nucleotide site (nt3) on the gpi111 locus.STn5 carried allele A1, possessing A→C muta-tions at nt156 and nt159 on the gltA1 locus.ST195 and ST208 accounted for 69.2%of all isolates.Clonal relationship analysis showed that ST 195 and ST208 belonged to CC92.Fifty-one A.baumannii isolates car-ried OXA-66 and the rest one carried OXA-199.Conclusion A.baumannii strains that belonged to CC92 and carried OXA-66 were the predominant genotype circulating in Guangzhou , China.