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: Cefoxitin resistance to beta-lactamase: a major factor for susceptibility of bacteroides fragilis to the antibiotic.
    Author: Darland G, Birnbaum J.
    Journal: Antimicrob Agents Chemother; 1977 Apr; 11(4):725-34. PubMed ID: 856025.
    Abstract:
    Toluene-treated cell suspensions of Bacteroides fragilis were used to screen clinical isolates for the production of beta-lactamase. Approximately one-third of the isolates possessed considerable cephalosporinase activity. A significant correlation was found between beta-lactamase production and resistance to cephalosporin antibiotics. Several isolates were resistant to cefuroxime and cefamandole and produced enzymes capable of hydrolyzing these antibiotics. However, none of the 79 strains tested could hydrolyze the cephamycin derivative, cefoxitin. A large percentage (>90%) of the strains were susceptible to cefoxitin. Therefore, resistance to lactamase hydrolysis is a major factor for the effectiveness of cefoxitin against B. fragilis. Detailed studies of four isolates suggest that two different enzymes may be produced. Both are cephalosporinases but differ with regard to cellular distribution and substrate specificity. Cefoxitin is not a substrate for either enzyme, but it is an excellent competitive inhibitor (K(i) approximately 0.1 muM).
    [Abstract] [Full Text] [Related] [New Search]