Display Settings:

Format

Send to:

Choose Destination

    J Bacteriol. 1995 Jun;177(11):2965-70.

    Characterization of the gene for the chromosomal dihydrofolate reductase (DHFR) of Staphylococcus epidermidis ATCC 14990: the origin of the trimethoprim-resistant S1 DHFR from Staphylococcus aureus?

    Dale GE, Broger C, Hartman PG, Langen H, Page MG, Then RL, Stüber D.

    Department of Gene Technologies, F. Hoffmann-La Roche Ltd., Basel, Switzerland.

    The gene for the chromosomally encoded dihydrofolate reductase (DHFR) of Staphylococcus epidermidis ATCC 14990 has been cloned and characterized. The structural gene encodes a polypeptide of 161 amino acid residues with a calculated molecular weight of 18,417. This trimethoprim-sensitive (Tmps) DHFR, SeDHFR, differs in only three amino acids (Val-31-->Ile, Gly-43-->Ala, and Phe-98-->Tyr) from the trimethoprim-resistant (Tmpr) S1 DHFR encoded by transposon Tn4003. Since in addition the S. epidermidis gene also forms part of an operon with thyE and open reading frame 140 as in Tn4003, the chromosomally located gene encoding the Tmps SeDHFR is likely to be the molecular origin of the plasmid-located gene encoding the Tmpr S1 DHFR. Site-directed mutagenesis and kinetic analysis of the purified enzymes suggest that a single Phe-->Tyr change at position 98 is the major determinant of trimethoprim resistance.

    PMID: 7768789 [PubMed - indexed for MEDLINE]

    PMCID: 176980

    Supplemental Content

    Click here to read Click here to read

    Patient drug information

    • Trimethoprim (Proloprim®)

      Trimethoprim eliminates bacteria that cause urinary tract infections. It is used in combination with other drugs to treat certain types of pneumonia. It also is used to treat 'travelers' diarrhea.' Antibiotics will not w...