Accession ARO:3002859
DefinitiondfrA14 is an integron-encoded dihydrofolate reductase found in Escherichia coli
AMR Gene Familytrimethoprim resistant dihydrofolate reductase dfr
Drug Classdiaminopyrimidine antibiotic
Resistance Mechanismantibiotic target replacement
ResistomesCitrobacter freundiiwgs, Enterobacter cloacaewgs, Enterobacter hormaecheiwgs, Escherichia coliwgs, Klebsiella oxytocawgs, Salmonella entericawgs, Serratia marcescensp, Shigella flexneriwgs, Shigella sonneiwgs, Yersinia enterocoliticawgs
Classification10 ontology terms | Show
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]

Marquez C, et al. 2008. Antimicrob Agents Chemother 52(11): 4153-4154. Recovery of a functional class 2 integron from an Escherichia coli strain mediating a urinary tract infection. (PMID 18794381)


Prevalence of dfrA14 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).

Prevalence: protein homolog model (view sequences)

SpeciesNCBI ChromosomeNCBI PlasmidNCBI WGS
Acinetobacter nosocomialis0%0%2%
Citrobacter amalonaticus0%0%22.22%
Citrobacter freundii0%2.33%7.75%
Enterobacter asburiae0%9.09%1.56%
Enterobacter cloacae6.67%9.09%7.45%
Enterobacter hormaechei0%5.41%31.7%
Enterobacter kobei0%0%3.12%
Escherichia coli0%0.64%3.05%
Klebsiella oxytoca0%3.33%13.08%
Klebsiella pneumoniae0%0%0%
Morganella morganii0%13.33%2.38%
Proteus mirabilis0%7.41%2.59%
Providencia rettgeri0%0%15.38%
Providencia stuartii0%7.14%15.38%
Raoultella planticola0%12.5%5.26%
Salmonella enterica0%0.7%1.13%
Serratia marcescens0%3.28%3.92%
Shigella dysenteriae0%0%2.86%
Shigella flexneri0%6.38%11.43%
Shigella sonnei0%0%7.76%
Vibrio parahaemolyticus0%0%0.17%
Yersinia enterocolitica0%0%1.3%
Show Perfect Only

Detection Models

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

>gb|ACI32877.1|+|dfrA14 [Escherichia coli]

>gb|EU780012|+|2163-2645|dfrA14 [Escherichia coli]