[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyo University Hospital--the second report].
We studied the high-level resistant to cefotaxime (CTX, MIC > or = 512 micrograms/ml) clinical isolates of Escherichia coli and Klebsiella pneumoniae in Teikyo University Hospital. The CTX-resistance could be transferred to E. coli K-12 chi 1037 or ML4903 strains from 30 of the 33 isolates by conjugation at a frequency of 10(-4). When the hydrolysis rate of benzylpenicillin was 100%, the beta-lactamases which were extracted from the transconjugants hydrolyzed CTX, CAZ and AZT at the rate of 38-95%, 0-8.6% and 0-56%, respectively. These results demonstrate that these enzymes should be categorized into ESBL. The nucleotide sequence of CTX-resistant gene was identified to that of the CTX-M2 gene which was first described in Argentina. It was found to have 99.9% homology to Toho-1 gene in Japan and 99.6% homology to CMY-2 gene. Using a PCR methods for the detection of one of ESBL gene such as CTX-M2, Toho-1 or CMY-2, the DNA was amplified from all strains (11 isolates of E. coli and 21 isolates of K. pneumoniae).
Kawakami
S
S
Department of Central Clinical Laboratory, Teikyo University School of Medicine.
Ono
Y
Y
Yamamoto
M
M
Matumura
M
M
Okamoto
R
R
Inoue
M
M
Miyazawa
Y
Y
D002439:Cefotaxime / Q000494:pharmacology*; D018550:Cephalosporin Resistance / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics*; D001618:beta-Lactamases / Q000032:analysis*
D001618:beta-Lactamases; D002439:Cefotaxime