These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Increase in ampC promoter strength due to mutations and deletion of the attenuator in a clinical isolate of cefoxitin-resistant Escherichia coli as determined by RT-PCR.
    Author: Tracz DM, Boyd DA, Bryden L, Hizon R, Giercke S, Van Caeseele P, Mulvey MR.
    Journal: J Antimicrob Chemother; 2005 May; 55(5):768-72. PubMed ID: 15761065.
    Abstract:
    OBJECTIVES: To characterize the mechanism of cefoxitin resistance in clinical isolate Escherichia coli N99-0001. METHODS: Plasmid analysis, PCR for beta-lactamases, and sequencing of the ampC genes was carried out. An RT-PCR method was developed to determine relative ampC expression. RESULTS: Analysis of the ampC promoter region of E. coli N99-0001 revealed a T-->A mutation at -32, a C-->A mutation at -11, an insertion of a T between -20 and -21, and a 28 bp deletion including the entire attenuator. RT-PCR showed that ampC was expressed 140-fold higher in E. coli N99-0001 than in E. coli ATCC 25922. CONCLUSIONS: Cefoxitin resistance in E. coli N99-0001 was due to overexpression of ampC caused by an increase in promoter strength.
    [Abstract] [Full Text] [Related] [New Search]