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PubMed · 1286571

Simple method for measuring the antibiotic concentration required to kill adherent bacteria.

Y Miyake·S Fujiwara·T Usui·H Suginaka
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Abstract

A simple method was developed for measuring the antibiotic susceptibility of bacteria adherent to plastic surfaces. Staphylococcus aureus cells adhered to the bottom of a 96-well plastic tissue culture plate were incubated in serially diluted antibiotic solutions. After a 24-hour-incubation the solutions were removed, and fresh medium without antibiotics was added to each well. The viability of the cells was judged by their growth after a further 24-hour-incubation. The antibiotic concentration required to kill adherent bacteria was far higher than that required for planktonic cells, although we used bactericidal drugs; beta-lactam, quinolone, and aminoglycoside antibiotics. The tolerance demonstrated by adherent cells is likely to play a role in the difficulties encountered in the chemotherapy of biofilm infections.

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Anti-Bacterial AgentsBacterial AdhesionMicrobial Sensitivity TestsPlasticsStaphylococcus aureusComparative StudyJournal Article

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Y Miyake, S Fujiwara, T Usui, H Suginaka. 1992. Simple method for measuring the antibiotic concentration required to kill adherent bacteria.. https://doi.org/10.1159/000239015

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