| Accession | ARO:3002854 |
| Synonym(s) | dfr1 |
| Definition | dfrA1 is an integron-encoded dihydrofolate reductase |
| AMR Gene Family | trimethoprim resistant dihydrofolate reductase dfr |
| Drug Class | diaminopyrimidine antibiotic |
| Resistance Mechanism | antibiotic target replacement |
| Resistomes | Citrobacter freundiip+wgs, Enterobacter asburiaewgs, Enterobacter cloacaep+wgs, Enterobacter hormaecheip+wgs, Enterobacter kobeiwgs, Escherichia colig+p+wgs, Klebsiella oxytocawgs, Proteus mirabiliswgs, Providencia rettgeriwgs, Providencia stuartiiwgs, Raoultella planticolawgs, Salmonella entericawgs, Shigella dysenteriaep+wgs, Shigella flexnerig+wgs, Shigella sonneiwgs |
| Classification | 10 ontology terms | Show + process or component of antibiotic biology or chemistry + mechanism of antibiotic resistance + antibiotic molecule + determinant of antibiotic resistance + antibiotic target replacement [Resistance Mechanism] + diaminopyrimidine antibiotic [Drug Class] + antibiotic target replacement protein + antibiotic resistant dihydrofolate reductase + determinant of diaminopyrimidine resistance + trimethoprim [Antibiotic] |
| Parent Term(s) | 3 ontology terms | Show + confers_resistance_to_antibiotic trimethoprim [Antibiotic] + derives_from antibiotic sensitive dihydrofolate reductase + trimethoprim resistant dihydrofolate reductase dfr [AMR Gene Family] |
| Publications | Saenz Y, et al. 2004. Antimicrob Agents Chemother 48(10): 3996-4001. Mechanisms of resistance in multiple-antibiotic-resistant Escherichia coli strains of human, animal, and food origins. (PMID 15388464) |
Prevalence of dfrA1 among the sequenced genomes, plasmids, and whole-genome shotgun assemblies available at NCBI for 82 important pathogens (see methodological details and complete list of analyzed pathogens). Values reflect percentage of genomes, plasmids, 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 |
|---|---|---|---|
| Acinetobacter baumannii | 1.91% | 0% | 1.31% |
| Citrobacter freundii | 6.9% | 1.16% | 16.28% |
| Enterobacter asburiae | 0% | 0% | 1.56% |
| Enterobacter cloacae | 0% | 2.6% | 8.13% |
| Enterobacter hormaechei | 0% | 3.6% | 7.13% |
| Enterobacter kobei | 0% | 0% | 12.5% |
| Escherichia coli | 0.15% | 0.64% | 5.34% |
| Klebsiella oxytoca | 0% | 0% | 14.02% |
| Klebsiella pneumoniae | 0% | 0% | 0% |
| Morganella morganii | 18.18% | 0% | 9.52% |
| Proteus mirabilis | 30.43% | 0% | 43.1% |
| Proteus penneri | 0% | 0% | 0% |
| Proteus vulgaris | 0% | 0% | 25% |
| Providencia rettgeri | 25% | 0% | 30.77% |
| Providencia stuartii | 14.29% | 0% | 23.08% |
| Pseudomonas stutzeri | 0% | 0% | 7.46% |
| Raoultella planticola | 0% | 0% | 5.26% |
| Salmonella enterica | 0% | 0% | 0.78% |
| Serratia marcescens | 0% | 0% | 6.22% |
| Shigella dysenteriae | 22.22% | 3.57% | 14.29% |
| Shigella flexneri | 27.27% | 2.13% | 59.48% |
| Shigella sonnei | 60% | 5.88% | 77.65% |
| Vibrio cholerae | 8.24% | 0% | 45.1% |
| Vibrio vulnificus | 0% | 0% | 0.68% |
| Yersinia enterocolitica | 0% | 0% | 0.65% |
Model Type: protein homolog model
Model Definition: The protein homolog model is an AMR detection model. Protein homolog models detect a protein sequence based on its similarity to a curated reference sequence. A protein homolog model has only one parameter: a curated BLASTP bitscore cutoff for determining the strength of a match. Protein homolog model matches to reference sequences are categorized on three criteria: perfect, strict and loose. A perfect match is 100% identical to the reference sequence along its entire length; a strict match is not identical but the bitscore of the matched sequence is greater than the curated BLASTP bitscore cutoff. Loose matches are other sequences with a match bitscore less than the curated BLASTP bitscore.
Bit-score Cut-off (blastP): 300