Accession ARO:3004141
DefinitionAn RND-type efflux system that confers innate aminoglycoside resistance to Achromobacter spp. It has a transcriptional regulator encoded by the axyZ gene located upstream of axyXY-oprZ. In-frame axyZ gene deletion assay led to increased MICs of antibiotic substrates of the efflux system: aminoglycosides, cefepime, fluoroquinolones, tetracyclines and erythromycin, indicating that the product of axyZ negatively regulates expression of axyXY-oprZ. Moreover a 45 amino-acid substitution at position 29 of AxyZ (V29G) was identified in a clinical Achromobacter strain that occurred during the course of chronic respiratory tract colonization in a cystic fibrosis (CF) patient. This substitution, also detected in 3 other strains exposed in vitro to tobramycin, led to the increase in axyY transcription level (5 to 17-fold) together with the increase in antibiotic resistance level.
AMR Gene Familyresistance-nodulation-cell division (RND) antibiotic efflux pump
Drug Classcephalosporin, macrolide antibiotic, aminoglycoside antibiotic, fluoroquinolone antibiotic
Resistance Mechanismantibiotic efflux
Efflux Componentefflux pump complex or subunit conferring antibiotic resistance
Classification10 ontology terms | Show
Parent Term(s)5 ontology terms | Show
+ resistance-nodulation-cell division (RND) antibiotic efflux pump [AMR Gene Family]
+ confers_resistance_to_antibiotic cefepime [Antibiotic]
+ confers_resistance_to_antibiotic erythromycin [Antibiotic]
+ confers_resistance_to_drug_class aminoglycoside antibiotic [Drug Class]
+ confers_resistance_to_drug_class fluoroquinolone antibiotic [Drug Class]
4 ontology terms | Show
+ OprZ part_of
+ AxyX part_of
+ AxyY part_of
+ AxyZ part_of

Bador J, et al. 2017. Antimicrob. Agents Chemother. : The role of AxyZ transcriptional regulator in the overproduction of AxyXY-OprZ multidrug efflux system in Achromobacter spp. mutants selected by tobramycin. (PMID 28584156)