Activity of human beta-defensins 2 and 3 against ESBL-producing Klebsiella strains.
OBJECTIVE
To test the bactericidal activity of human beta-defensins (hBDs) 2 and 3 against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella strains.


METHODS
Thirty-six Klebsiella pneumoniae and seventeen Klebsiella oxytoca ESBL-producing isolates from nosocomial infections were tested. The bactericidal activity of recombinantly synthesized hBD-2 and -3 was tested and the results were given either as lethal doses killing > or = 90% of bacteria (LD90s) or as MBCs (> or = 99.9% killing).


RESULTS
Except for one intermediately susceptible strain (MBC = 25 mg/L), all other ESBL-producing strains were highly susceptible to both defensins (LD90s and MBCs < or = 12.5 mg/L).


CONCLUSIONS
The results underline the high efficacy of hBD-2 and -3 against ESBL-producing Klebsiella, making both defensins attractive candidates as antimicrobial agents to combat these increasingly troublesome bacteria.
Sahly
Hany
H
Institute of Infection Medicine, Faculty of Medicine, University of Kiel, Brunswiker Strasse 4, 24105 Kiel, Germany. sahly@infmed.uni-kiel.de
Schubert
Sabine
S
Harder
Jürgen
J
Kleine
Michael
M
Sandvang
Dorthe
D
Ullmann
Uwe
U
Schröder
Jens M
JM
Podschun
Rainer
R
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D006801:Humans; D041121:Klebsiella oxytoca / Q000187:drug effects* / Q000201:enzymology*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology*; D023083:beta-Defensins / Q000494:pharmacology*; D001618:beta-Lactamases / Q000378:metabolism*
D000900:Anti-Bacterial Agents; C422950:DEFB103A protein, human; C106641:DEFB4A protein, human; D023083:beta-Defensins; D001618:beta-Lactamases