| Accession | ARO:3000378 |
| CARD Short Name | MexB |
| Definition | MexB is the inner membrane multidrug exporter of the efflux complex MexAB-OprM. |
| AMR Gene Family | resistance-nodulation-cell division (RND) antibiotic efflux pump |
| Drug Class | peptide antibiotic, diaminopyrimidine antibiotic, sulfonamide antibiotic, phenicol antibiotic, penam, macrolide antibiotic, carbapenem, cephalosporin, tetracycline antibiotic, monobactam, fluoroquinolone antibiotic, aminocoumarin antibiotic, penem, cephamycin |
| Resistance Mechanism | antibiotic efflux |
| Efflux Component | efflux pump complex or subunit conferring antibiotic resistance |
| Resistomes with Sequence Variants | Acinetobacter baumanniiwgs, Acinetobacter nosocomialiswgs, Burkholderia multivoranswgs, Enterobacter hormaecheiwgs, Escherichia coliwgs, Klebsiella pneumoniaewgs, Pseudomonas aeruginosag+p+wgs, Pseudomonas fluorescensg, Staphylococcus aureuswgs, Stenotrophomonas maltophiliawgs, Vibrio vulnificuswgs |
| Classification | 47 ontology terms | Show + process or component of antibiotic biology or chemistry + antibiotic molecule + peptide antibiotic [Drug Class] + lipopeptide antibiotic + beta-lactam antibiotic + mechanism of antibiotic resistance + determinant of antibiotic resistance + diaminopyrimidine antibiotic [Drug Class] + polymyxin antibiotic + antibiotic efflux [Resistance Mechanism] + cephem + sulfonamide antibiotic [Drug Class] + trimethoprim [Antibiotic] + phenicol antibiotic [Drug Class] + colistin + penam [Drug Class] + macrolide antibiotic [Drug Class] + carbapenem [Drug Class] + efflux pump complex or subunit conferring antibiotic resistance [Efflux Component] + cephalosporin [Drug Class] + tetracycline antibiotic [Drug Class] + antibiotic mixture + monobactam [Drug Class] + fluoroquinolone antibiotic [Drug Class] + sulfamethoxazole [Antibiotic] + aminocoumarin antibiotic [Drug Class] + ciprofloxacin [Antibiotic] + colistin B [Antibiotic] + aztreonam [Antibiotic] + azithromycin [Antibiotic] + panipenem [Antibiotic] + colistin A [Antibiotic] + ceftazidime [Antibiotic] + chloramphenicol [Antibiotic] + resistance-nodulation-cell division (RND) antibiotic efflux pump [AMR Gene Family] + erythromycin [Antibiotic] + trimethoprim-sulfamethoxazole [Antibiotic] + ceftriaxone [Antibiotic] + ampicillin [Antibiotic] + penem [Drug Class] + tetracycline [Antibiotic] + meropenem [Antibiotic] + novobiocin [Antibiotic] + cephamycin [Drug Class] + MexAB-OprM + nalidixic acid [Antibiotic] + ticarcillin [Antibiotic] |
| Parent Term(s) | 7 ontology terms | Show + part_of MexAB-OprM + subunit of efflux pump conferring antibiotic resistance + part_of MexAB-OprM with prematurely terminated MexR conferring resistance to meropenem and ciprofloxacin + part_of MexAB-OprM with NalC mutations conferring resistance to aztreonam + part_of MexAB-OprM with NalD mutations conferring resistance to multiple antibiotics + part_of MexAB-OprM with CpxR regulator conferring resistance to ciprofloxacin, ceftazidime, and aztreonam + part_of MexAB-OprM with MexR mutations confers resistance to multiple antibiotics |
| Publications | Sennhauser G, et al. 2009. J Mol Biol 389(1): 134-145. Crystal structure of the multidrug exporter MexB from Pseudomonas aeruginosa. (PMID 19361527) Bhatt FH and Jeffery CJ. 2010. J Vis Exp 46. Expression, detergent solubilization, and purification of a membrane transporter, the MexB multidrug resistance protein. (PMID 21178960) Welch A, et al. 2010. Biochem J 430(2): 355-364. Promiscuous partnering and independent activity of MexB, the multidrug transporter protein from Pseudomonas aeruginosa. (PMID 20583998) Middlemiss JK and Poole K. 2004. J Bacteriol 186(5): 1258-1269. Differential impact of MexB mutations on substrate selectivity of the MexAB-OprM multidrug efflux pump of Pseudomonas aeruginosa. (PMID 14973037) |
Prevalence of MexB among the sequenced genomes, plasmids, and whole-genome shotgun assemblies available at NCBI or IslandViewer for 377 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 |
|---|---|---|---|---|
| Acinetobacter baumannii | 0% | 0% | 0.02% | 0% |
| Acinetobacter nosocomialis | 0% | 0% | 0.65% | 0% |
| Burkholderia multivorans | 0% | 0% | 0.96% | 0% |
| Enterobacter hormaechei | 0% | 0% | 0.05% | 0% |
| Escherichia coli | 0% | 0% | 0.01% | 0% |
| Klebsiella pneumoniae | 0% | 0% | 0.03% | 0% |
| Pseudomonas aeruginosa | 99.81% | 0.64% | 75.36% | 0% |
| Pseudomonas fluorescens | 2.86% | 0% | 0% | 0% |
| Staphylococcus aureus | 0% | 0% | 0.01% | 0% |
| Stenotrophomonas maltophilia | 0% | 0% | 0.34% | 0% |
| Vibrio vulnificus | 0% | 0% | 0.4% | 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): 1950
