OXA-51-like beta-lactamases and their association with particular epidemic lineages of Acinetobacter baumannii.
Sixty diverse clinical Acinetobacter baumannii isolates of worldwide origin were assigned to sequence groups, based on a multiplex PCR for the ompA, csuE and bla(OXA-51-like) genes. The majority (77%) of isolates belonged to sequence groups 1 and 2 (SG1 and SG2), with sequence group 3 (SG3) and non-grouped isolates accounting for the remainder. The isolates were not closely related according to pulsed-field gel electrophoresis (PFGE), and the majority were sensitive to imipenem and meropenem. The construction of a linkage map of OXA-51-like beta-lactamase sequence relationships revealed two closely related clusters of enzymes, one focused around OXA-66 and the other around OXA-69. Isolates belonging to SG1 encoded an enzyme from the OXA-66 cluster, while those belonging to SG2 encoded an enzyme from the OXA-69 cluster. All SG3 isolates encoded OXA-71, which does not form part of a close enzyme grouping. Major multinational lineages accounted for a significant proportion of A. baumannii clinical isolates, and the evolution of the OXA-51-like enzymes appears to be an ongoing process.
Evans
B A
BA
Centre for Infectious Diseases, The University of Edinburgh, Edinburgh, UK.
Hamouda
A
A
Towner
K J
KJ
Amyes
S G B
SG
D000151:Acinetobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000145:classification* / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D019143:Evolution, Molecular; D005838:Genotype; D006801:Humans; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000235:genetics*
D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; C078167:OMPA outer membrane proteins; D001618:beta-Lactamases