Methods for the detection of beta-lactamases in a sample
Presented herein are methods for the detection of specific beta-lactamases, including class A serine carbapenemases, metallo-beta-lactamases, AmpC beta-lactamases, and extended-spectrum beta-lactamases (ESBLs). The methods presented herein include methods that permit the detection of the presence of specific beta-lactamases in bacterial samples within as few as 2 to 10 minutes.
1. A method for detecting the presence of a beta-lactamase in a sample, comprising:
(a) providing a solid support comprising a plurality of wells, the plurality of wells comprising:
i) a first well containing a dry composition comprising a lysis reagent, and
ii) a second well containing a dry composition comprising a beta-lactamase substrate;
(b) rehydrating the dry composition in the first and second well;
(c) contacting a bacterial sample with the composition in the first well;
(d) contacting the bacterial sample with the composition in the second well; and
(e) detecting utilization of the beta-lactamase substrate in the second well,
wherein utilization of the beta-lactamase substrate indicates the presence of a beta-lactamase.
2. The method of claim 1 , wherein the beta-lactamase substrate is an antibiotic.
3. The method of claim 1 , wherein the plurality of wells further comprise a third well containing a dry composition comprising a beta-lactamase substrate and one or more beta-lactamase inhibitors, and wherein the method further comprises:
(b)′ rehydrating the dry composition in the third well;
(d)′ contacting the bacterial sample with the composition in the third well; and
(e)′ detecting utilization of the beta-lactamase substrate in the third well,
wherein utilization of the beta-lactamase substrate in the third well indicates the presence of a beta-lactamase not inhibited by the one or more beta-lactamase inhibitors.