Selection during cefepime treatment of a new cephalosporinase variant with extended-spectrum resistance to cefepime in an Enterobacter aerogenes clinical isolate.
Enterobacter aerogenes resistant to cefepime (MIC, 32 microg/ml) was isolated from a patient treated with cefepime for an infection caused by a strain of E. aerogenes overproducing its AmpC beta-lactamase (MIC of cefepime, 0.5 microg/ml). The AmpC beta-lactamase of the resistant strain had an L-293-P amino acid substitution and a high k(cat)/K(m) ratio for cefepime. Both of these modifications were necessary for resistance to cefepime.
Service de Bactériologie, Hôpital Tenon AP-H, Hôpital Lariboisière AP-HP, Paris. guilene.barnaud@lmr.ap-hop-paris.fr
G
G
Barnaud
Y
Y
Benzerara
J
J
Gravisse
L
L
Raskine
M J
MJ
Sanson-Le Pors
R
R
Labia
G
G
Arlet
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics; D000077723:Cefepime; D002510:Cephalosporinase / Q000235:genetics / Q000378:metabolism*; D002511:Cephalosporins / Q000494:pharmacology* / Q000627:therapeutic use; D016521:Electrophoresis, Gel, Pulsed-Field; D021902:Enterobacter aerogenes / Q000187:drug effects* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000188:drug therapy / Q000382:microbiology*; D005798:Genes, Bacterial / Q000235:genetics; D007700:Kinetics; D008969:Molecular Sequence Data
D002511:Cephalosporins; D000077723:Cefepime; D002510:Cephalosporinase