TABLE 2.

Mechanisms of resistance in Acinetobacter baumannii

Antimicrobial class and resistance mechanismEnzyme(s)aReference(s)
β-Lactams
    β-LactamasesTEM 148, 387
SHV 248, 387
ADCs 49, 249, 250, 427, 468
VEB 71, 381, 382, 417, 442
PER 250, 381, 385, 417, 439, 565, 611
CTX-M 76, 386
OXAThis study
IMP 89, 104, 113, 179, 246, 265, 298, 316, 402, 471, 506, 530, 544, 618
VIM 316, 335, 551, 606, 615
SIM 320
    OMPsCarO (29 kDa) 336, 380, 511
47-, 44-, and 37-kDa OMPs 446
22- and 33-kDa OMPs 47
HMP-AB 209
33- to 36-kDa OMPs 94, 119
43-kDa OMP 141
OmpW 510
    EffluxAdeABC 232, 236, 347, 420
    Altered penicillin-binding proteinsAltered penicillin-binding proteins 165, 188, 405, 510
Aminoglycosides
    Aminoglycoside-modifying enzymesAcetyltransferases, nucleotidyltransferases, phosphotransferases 246, 250, 320, 395, 458, 503, 551, 556, 618
    Ribosomal (16S rRNA) methylation 129, 314, 608
    EffluxAdeABC 347
AdeM 525
Quinolones
    Modification to target binding siteGyrA, ParC 220, 236, 504, 581, 582
    EffluxAdeABC 236, 347
AdeM 525
Tetracyclines and glycylcyclines
    Tetracycline-specific effluxTet(A), Tet(B) 217, 455, 457
    Ribosomal protectionTet(M) 457
    Multidrug effluxAdeABC 347, 420, 469
  • a ADCs, Acinetobacter-derived cephalosporinases; HMP-AB, heat-modifiable protein in Acinetobacter baumannii.