Genetically diverse ceftazidime-resistant isolates from a single center: biochemical and genetic characterization of TEM-10 beta-lactamases encoded by different nucleotide sequences.
Ceftazidime-resistant isolates of Escherichia coli and Klebsiella pneumoniae produced a plasmid-mediated beta-lactamase with a pI of 5.6 with biochemical characteristics comparable to those of the TEM-10 beta-lactamase. Plasmids from the two strains were nonidentical. Both TEM-10 sequences differed from TEM-1 by substitutions of Ser-162 and Lys-237. The nucleotide sequences of the two genes were identical except for three silent nucleotide substitutions corresponding to the nucleotide differences in the Tn2 TEM-1 or Tn3 TEM-1 genes. The original TEM-10 plasmid was identical to that found in the E. coli isolate and coded for a gene that corresponded to the TEM-10 beta-lactamase from Tn2.
Rasmussen
B A
BA
Medical Research Division, American Cyanamid, Pearl River, New York 10965.
Bradford
P A
PA
Quinn
J P
JP
Wiener
J
J
Weinstein
R A
RA
Bush
K
K
D002442:Ceftazidime / Q000494:pharmacology*; D003001:Cloning, Molecular; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D006801:Humans; D007525:Isoelectric Focusing; D007700:Kinetics; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D010957:Plasmids; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D002442:Ceftazidime; C084251:beta-lactamase TEM-10; D001618:beta-Lactamases