Accession ARO:3002858
DefinitiondfrA12 is an integron-encoded dihydrofolate reductase found in Vibrio cholerae
AMR Gene Familytrimethoprim resistant dihydrofolate reductase dfr
Drug Classdiaminopyrimidine antibiotic
Resistance Mechanismantibiotic target replacement
ResistomesAcinetobacter baumanniig+wgs, Citrobacter freundiip+wgs, Citrobacter koserig, Citrobacter youngaewgs, Enterobacter cloacaep+wgs, Enterobacter hormaecheig+p+wgs, Enterobacter kobeiwgs, Escherichia colig+p+wgs, Klebsiella aerogenesg+p+wgs, Klebsiella oxytocawgs, Klebsiella pneumoniaeg+p+wgs, Morganella morganiig+wgs, Proteus mirabilisg+p+wgs, Proteus vulgarisp, Providencia rettgerip, Providencia stuartiig+wgs, Raoultella planticolawgs, Salmonella entericag+p+wgs, Shigella flexneriwgs, Shigella sonneiwgs, Vibrio choleraewgs
Classification9 ontology terms | Show
Parent Term(s)2 ontology terms | Show

Thungapathra M, et al. 2002. Antimicrob Agents Chemother 46(9): 2948-2955. Occurrence of antibiotic resistance gene cassettes aac(6')-Ib, dfrA5, dfrA12, and ereA2 in class I integrons in non-O1, non-O139 Vibrio cholerae strains in India. (PMID 12183252)

Miriagou V, et al. 2010. Antimicrob. Agents Chemother. 54(10):4497-502 Sequence of pNL194, a 79.3-kilobase IncN plasmid carrying the blaVIM-1 metallo-beta-lactamase gene in Klebsiella pneumoniae. (PMID 20660690)


Prevalence of dfrA12 among the sequenced genomes, plasmids, and whole-genome shotgun assemblies available at NCBI for 88 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 baumannii0.54%0%0.12%
Acinetobacter nosocomialis0%0%1.1%
Citrobacter freundii0%2.83%9.55%
Citrobacter koseri12.5%0%0%
Citrobacter youngae0%0%12.5%
Enterobacter cloacae0%1.15%1.76%
Enterobacter hormaechei1.61%4.4%7.21%
Enterobacter kobei0%0%4.35%
Escherichia coli0.57%1.26%6.52%
Klebsiella aerogenes3.45%4%0.94%
Klebsiella oxytoca0%0%1.17%
Klebsiella pneumoniae2.59%3.44%26.29%
Morganella morganii17.65%0%3.57%
Proteus mirabilis11.9%13.89%3.91%
Proteus vulgaris0%25%0%
Providencia rettgeri0%20%0%
Providencia stuartii10%0%4.17%
Raoultella planticola0%0%3.57%
Salmonella enterica0.99%2.25%1.46%
Shigella flexneri0%0%0.83%
Shigella sonnei0%0%1.48%
Vibrio cholerae0%0%0.24%
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|ADG84870.1|-|dfrA12 [Klebsiella pneumoniae]

>gb|GU585907.1|-|21606-22103|dfrA12 [Klebsiella pneumoniae]