A Deferred Growth Inhibition Assay to Evaluate the Effect of Bacteria-Derived Antimicrobial Compounds

Abstract

Source: Moran, J. C. et al., Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition. J. Vis. Exp. (2016)

This video showcases the deferred growth inhibition assay, used to investigate how antimicrobial compounds produced by one type of bacteria affect another competing bacterial strain.

Protocol

The following method is adapted to test competitor strains with inhibitor-producing strains.

NOTE: This protocol involves aerosol generation with bacterial cultures. This can only be performed in a contained space with the implementation of locally approved safety considerations. Spraying of the culture onto the agar plates within a level 2 safety cabinet will minimize contamination of the agar plates and the surrounding environment. This will also protect the researcher from aerosol inhalation of the sprayed bacteria, this is a major concern if the researcher is using containment level 2 organisms. Appropriate personal pro....

Results

Figure 1: The range of qualitative and quantitative results that can be obtained from the deferred growth inhibition assay. Results for the growth inhibit.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Brain heart infusion broth	Lab M	lab049	Rich general purpose media
Agar-agar	Merck Milipore	101614
Petri dishes	Sarstedt	82.1473.001
Plastic perfume vaporizer	not known	-	10 cm high with 3.5 cm diameter clear plastic spray bottle with lid, purchased from the travel section of a supermarket
Universal bottles		no longer in production, alternative SLS BOT5006	28 ml glass cylindrical bottle (approx 280 mm diameter, 850 mm height), flat bottomed with plastic screw cap
Decon 90	Decon		surface active cleaning agent