Paper
Organic & Biomolecular Chemistry
as the lowest concentration of test compound at which no
visible growth of bacteria was observed.
Acknowledgements
BROTH MICRODILUTION METHOD FOR ANTIBIOTIC RESENSITIZATION. Muel- The authors thank the DOD DMRDP program (W81XWH-11-2-
ler–Hinton broth (MHB) was inoculated (5 × 105 CFU mL−1
0115) for support of this work. The DMRDP program is admi-
)
with MRSA (BAA-44). The resulting bacterial suspension was nistered by the Department of Army, The U.S. Army Medical
aliquoted (5 mL) into culture tubes and test compound (from Research Acquisition Activity, 820 Chandler Street, Fort
its DMSO stock) was added to give the final concentration to Detrick, MD 21702-5014 is the awarding and administering
be tested. Bacteria not treated with the tested 2-AI derivative office. The content of this manuscript does not necessarily
served as the control. After sitting for 30 min at room tempera- reflect the position or the policy of the Government, and no
ture, 1 mL of each sample was transferred to a new culture official endorsement should be inferred.
tube and oxacillin was added from 128 mg mL−1 water stock to
give a concentration of 128 μg mL−1. Rows 2–12 of a 96-well
microtiter plate were filled with 100 μL per well from the
remaining 3 mL bacterial subcultures, allowing the concen-
tration of compound to be kept uniform throughout the anti-
Notes and references
biotic dilution procedure. After standing for 10 min, the
samples containing antibiotic were aliquoted (200 μL) into the
corresponding first row wells of the microtiter plate. Row 1
wells were mixed 6 to 8 times then 100 μL was transferred to
row 2. Row 2 wells were mixed 6 to 8 times, followed by a
100 μL transfer from row 2 to row 3. This procedure was
repeated to serially dilute the rest of the rows of the microtiter
plate, with the exception of the final row, to which no anti-
biotic was added. The plate was then sealed with GLAD Press
n’ Seal® and incubated under stationary conditions at 37 °C.
After 16 h, minimum inhibitory concentration (MIC) values
were recorded as the lowest concentration of antibiotic at
which no visible growth of bacteria was observed.
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Chem., 2008, 6, 1356–1363.
136 | Org. Biomol. Chem., 2013, 11, 130–137
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