dfrB1

Accession ARO:3002864
Synonym(s)dfr2a dfrII
CARD Short NamedfrB1
DefinitionA plasmid-associated trimethoprim-resistant dihydrofolate reductase detected in Bordetella bronchispetica on pKBB958.
AMR Gene Familytrimethoprim resistant dihydrofolate reductase dfr
Drug Classdiaminopyrimidine antibiotic
Resistance Mechanismantibiotic target replacement
Resistomes with Perfect MatchesAcinetobacter baumanniiwgs, Citrobacter freundiip+wgs, Citrobacter portucalensiswgs, Enterobacter cloacaep+wgs, Enterobacter hormaecheip+wgs, Enterobacter roggenkampiiwgs, Escherichia colip+wgs, Klebsiella michiganensiswgs, Klebsiella oxytocap, Klebsiella pneumoniaewgs, Klebsiella quasipneumoniaewgs, Providencia rettgeriwgs, Pseudomonas aeruginosawgs, Salmonella entericawgs, Serratia marcescenswgs
Resistomes with Sequence VariantsAcinetobacter baumanniiwgs, Citrobacter freundiip+wgs, Citrobacter portucalensiswgs, Enterobacter cloacaep+wgs, Enterobacter hormaecheip+wgs, Enterobacter roggenkampiiwgs, Escherichia colip+wgs, Klebsiella michiganensiswgs, Klebsiella oxytocap, Klebsiella pneumoniaewgs, Klebsiella quasipneumoniaewgs, Providencia rettgeriwgs, Pseudomonas aeruginosawgs, Salmonella entericawgs, Serratia marcescenswgs
Classification9 ontology terms | Show
Parent Term(s)3 ontology terms | Show
+ trimethoprim resistant dihydrofolate reductase dfr [AMR Gene Family]
+ derives_from antibiotic sensitive dihydrofolate reductase
+ confers_resistance_to_antibiotic trimethoprim [Antibiotic]
Publications

Kadlec K, et al. 2005. J Antimicrob Chemother 56(3): 485-490. Molecular basis of resistance to trimethoprim, chloramphenicol and sulphonamides in Bordetella bronchiseptica. (PMID 16046466)

Resistomes

Prevalence of dfrB1 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 (view sequences)

SpeciesNCBI ChromosomeNCBI PlasmidNCBI WGSNCBI GI
Acinetobacter baumannii0%0%0.03%0%
Citrobacter freundii0%0.31%1.74%0%
Citrobacter portucalensis0%0%0.9%0%
Enterobacter cloacae0%0.56%0.32%0%
Enterobacter hormaechei0%0.13%0.39%0%
Enterobacter roggenkampii0%0%0.72%0%
Escherichia coli0%0.01%0.01%0%
Klebsiella michiganensis0%0%0.27%0%
Klebsiella oxytoca0%0.68%0%0%
Klebsiella pneumoniae0%0%0.14%0%
Klebsiella quasipneumoniae0%0%0.13%0%
Providencia rettgeri0%0%0.64%0%
Pseudomonas aeruginosa0%0%0.14%0%
Salmonella enterica0%0%0.01%0%
Serratia marcescens0%0%0.39%0%
Show Perfect Only


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): 175


>gb|AAA82255.1|+|dfrB1 [Escherichia coli]
MERSSNEVSNPVAGNFVFPSNATFGMGDRVRKKSGAAWQGQIVGWYCTNLTPEGYAVESEAHPGSVQIYPVAALERIN


>gb|U36276.1|+|717-953|dfrB1 [Escherichia coli]
ATGGAACGAAGTAGCAATGAAGTCAGTAATCCAGTTGCTGGCAATTTTGTATTCCCATCGAACGCCACGTTTGGTATGGGAGATCGCGTG
CGCAAGAAATCCGGCGCCGCCTGGCAAGGTCAGATTGTCGGGTGGTACTGCACAAATTTGACCCCCGAAGGCTACGCCGTCGAGTCTGAG
GCTCACCCAGGCTCAGTACAGATTTATCCTGTTGCGGCGCTTGAACGCATCAACTGA