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: RAHN-2, a chromosomal extended-spectrum class A beta-lactamase from Rahnella aquatilis.
    Author: Ruimy R, Meziane-Cherif D, Momcilovic S, Arlet G, Andremont A, Courvalin P.
    Journal: J Antimicrob Chemother; 2010 Aug; 65(8):1619-23. PubMed ID: 20511369.
    Abstract:
    OBJECTIVES: Rahnella aquatilis is an environmental enterobacterial species with a chromosomal bla(RAHN-1) gene encoding extended-spectrum class A beta-lactamase RAHN-1. We describe the diversity of bla(RAHN) genes from two groups of strains, G1 and G2, isolated from raw fruits and vegetables, and the new class A beta-lactamase RAHN-2. METHODS: MICs were determined by Etest. bla(RAHN) genes were amplified by PCR, sequenced, and cloned to produce RAHN-1 and RAHN-2 proteins whose kinetic parameters were determined. RESULTS: All strains had similar beta-lactam resistance patterns. However, isolates of G1 were at least 2-fold more susceptible to piperacillin, amoxicillin, piperacillin/clavulanic acid, piperacillin/tazobactam and cefotaxime. Sequences of bla(RAHN) from G1 had <82.9% identity with that of bla(RAHN-1), whereas those of G2 were >92% identical. The RAHN-2 beta-lactamase was 89.8% identical to RAHN-1, 5-fold more efficient than RAHN-1 in hydrolysing ticarcillin and 2.5-fold more efficient in cefotaxime and cefuroxime hydrolysis. However, the specific activity of RAHN-1 was 2-fold higher than that of RAHN-2 suggesting that the bla(RAHN) genes are regulated differently. CONCLUSIONS: The new class A beta-lactamase RAHN-2 is phenotypically difficult to detect and requires MIC determination.
    [Abstract] [Full Text] [Related] [New Search]