| Accession | ARO:3002716 |
| CARD Short Name | QnrB3 |
| Definition | QnrB3 is a plasmid-mediated quinolone resistance protein found in Escherichia coli. |
| AMR Gene Family | quinolone resistance protein (qnr) |
| Drug Class | fluoroquinolone antibiotic |
| Resistance Mechanism | antibiotic target protection |
| Resistomes with Perfect Matches | Enterobacter hormaecheiwgs |
| Resistomes with Sequence Variants | Citrobacter freundiiwgs, Enterobacter hormaecheiwgs |
| Classification | 14 ontology terms | Show + process or component of antibiotic biology or chemistry + antibiotic molecule + mechanism of antibiotic resistance + determinant of antibiotic resistance + antibiotic target protection [Resistance Mechanism] + fluoroquinolone antibiotic [Drug Class] + sparfloxacin [Antibiotic] + norfloxacin [Antibiotic] + nalidixic acid [Antibiotic] + gatifloxacin [Antibiotic] + antibiotic target protection protein + moxifloxacin [Antibiotic] + levofloxacin [Antibiotic] + ciprofloxacin [Antibiotic] |
| Parent Term(s) | 2 ontology terms | Show + confers_resistance_to_antibiotic ciprofloxacin [Antibiotic] + quinolone resistance protein (qnr) [AMR Gene Family] |
| Publications | Robicsek A, et al. 2006. Antimicrob Agents Chemother 50(8): 2872-2874. qnr prevalence in ceftazidime-resistant Enterobacteriaceae isolates from the United States. (PMID 16870791) |
Prevalence of QnrB3 among the sequenced genomes, plasmids, and whole-genome shotgun assemblies available at NCBI or IslandViewer for 413 important pathogens (see methodological details and complete list of analyzed pathogens). Values reflect percentage of genomes, plasmids, genome islands, or whole-genome shotgun assemblies that have at least one hit to the AMR detection model. Default view includes percentages calculated based on Perfect plus Strict RGI hits. Select the checkbox to view percentages based on only Perfect matches to AMR reference sequences curated in CARD (note: this excludes resistance via mutation as references in protein variant models are often wild-type, sensitive sequences).
| Species | NCBI Chromosome | NCBI Plasmid | NCBI WGS | NCBI GI |
|---|---|---|---|---|
| Citrobacter freundii | 0% | 0% | 0.19% | 0% |
| Enterobacter hormaechei | 0% | 0% | 0.04% | 0% |
Model Type: protein homolog model
Model Definition: Protein Homolog Models (PHM) detect protein sequences based on their similarity to a curated reference sequence, using curated BLASTP bitscore cut-offs. Protein Homolog Models apply to all genes that confer resistance through their presence in an organism, such as the presence of a beta-lactamase gene on a plasmid. PHMs include a reference sequence and a bitscore cut-off for detection using BLASTP. A Perfect RGI match is 100% identical to the reference protein sequence along its entire length, a Strict RGI match is not identical but the bit-score of the matched sequence is greater than the curated BLASTP bit-score cutoff, Loose RGI matches have a bit-score less than the curated BLASTP bit-score cut-off.
Bit-score Cut-off (blastP): 400