Open AccessOuter membrane protein profiles of clonally related Klebsiella pneumoniae isolates that differ in cefoxitin resistance
Author(s) -
ŠkopkováŽarnayová Martina,
Siebor Eliane,
Rovná Daniela,
Bujdáková Helena,
Neuwirth Catherine
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2004.12.023
Subject(s) - cefoxitin , microbiology and biotechnology , aztreonam , klebsiella pneumoniae , porin , cefepime , cefotaxime , ceftazidime , imipenem , moxalactam , cephalosporin , biology , bacterial outer membrane , ciprofloxacin , meropenem , antibacterial agent , ertapenem , antibiotics , antibiotic resistance , bacteria , pseudomonas aeruginosa , escherichia coli , biochemistry , gene , genetics , staphylococcus aureus
Eleven genotypically related Klebsiella pneumoniae isolates were obtained from 11 patients. All isolates were resistant to third‐generation cephalosporins due to the production of SHV‐2a extended‐spectrum β‐lactamase. Comparison of the outer membrane protein profiles revealed one isolate that lacked porins. This porin‐deficient isolate was also resistant to cefoxitin (MIC 128 μg ml −1 ) and moxalactam (MIC 64 μg ml −1 ) and had elevated MIC of meropenem (2 μg ml −1 ) when compared to porin‐expressing isolates (2–8, 4 and <0.06–0.125 μg ml −1 , respectively). Higher MICs, associated with loss of porins in outer membrane, were also observed for cefotaxime (4–8‐fold), cefepime (>2–16‐fold), ciprofloxacin (4–16‐fold), imipenem and aztreonam (2–16‐fold), but there was no significant difference among MICs of ceftazidime. The porin‐deficient mutant was probably selected in vivo during ofloxacin therapy.