Open AccessSulfonamide resistance mechanism in Escherichia coli: R plasmids can determine sulfonamide-resistant dihydropteroate synthases.
Author(s) -
Edmund M. Wise,
Martha M. AbouDonia
Publication year - 1975
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.72.7.2621
Subject(s) - dihydropteroate synthase , sulfonamide , dhps , escherichia coli , microbiology and biotechnology , enzyme , klebsiella pneumoniae , chemistry , biology , biochemistry , stereochemistry , pyrimethamine , plasmodium falciparum , malaria , gene , immunology
Several natural isolate E. coli strains highly resistant to sulfonamides and antibiotics are shown to contain a sulfonamide-resistant dihydropteroate synthase (2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine-diphosphate:4-aminobenzoate 2-amino-4-hydroxydihydropteridine-6-methenyltransferase, EC 2.5.1.15) in addition to the normal sensitive enzyme. The resistant dihydropteroate synthases examined are determined by an R plasmid and are smaller and less heat stable than the normal sulfonamide-sensitive enzyme. One synthase resistant to any sulfonamide tested, and to sulfanilic and arsanilic acids, was still inhibited by several non-sulfonamide analogs of p-aminobenzoate. Citrobacter and Klebsiella pneumoniae strains also show similar mechanisms of sulfonamide resistance.