Trimethoprim-resistant dihydrofolate reductase DfrA43

Accession ARO:3005345
CARD Short NameDfrA43_TMP
DefinitionDfrA43 is a dihydrofolate reductase that confers resistance to Trimethoprim. Originially described by Shi YZ et al, 2016, and isolated from Proteus penneri.
AMR Gene Familytrimethoprim resistant dihydrofolate reductase dfr
Drug Classdiaminopyrimidine antibiotic
Resistance Mechanismantibiotic target replacement
Classification9 ontology terms | Show
Parent Term(s)2 ontology terms | Show
+ trimethoprim resistant dihydrofolate reductase dfr [AMR Gene Family]
+ confers_resistance_to_antibiotic trimethoprim [Antibiotic]

Li L, et al. 2021. Antimicrob Agents Chemother : Identification and characterization of two novel ISCR1-associated genes dfrA42 and dfrA43 encoding trimethoprim resistant dihydrofolate reductases. (PMID 33593833)


Prevalence of Trimethoprim-resistant dihydrofolate reductase DfrA43 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).

Prevalence: protein homolog model

SpeciesNCBI ChromosomeNCBI PlasmidNCBI WGSNCBI GI
No prevalence data

Detection Models

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): 350

>gb|WP_188331861.1|+|Trimethoprim-resistant dihydrofolate reductase DfrA43 [Proteus penneri]

>gb|NG_070721.1|+|101-688|Trimethoprim-resistant dihydrofolate reductase DfrA43 [Proteus penneri]