This video demonstrates an assay for screening antimicrobial compounds that efficiently eliminate biofilms using a peg-plate. The methodology monitors the biofilm's metabolic state after treatment with antimicrobial compounds, facilitating the determination of the minimum biofilm eradication concentration.
Protocol
1. Biofilm Initiation Grow a culture of biofilm-producing organisms in a nutrient-rich medium. Inoculate Staphylococcus aureus strain Newman in 10 ml of Mueller-Hinton medium from a glycerol stock. Perform all work involving handling of S. aureus with gloves and within a biosafety cabinet. Incubate for 16 hr at 37 °C on a rotary shaker (100-200 rpm). Determine OD600 of the culture using a spectrophotometer and a st…
Representative Results
Figure 1. Challenge plate layout. Example layout of challenge plate accommodating parallel testing of four compounds in triplicate at six distinct concentrations. Untreated and sterility controls are also included. The layout design supports convenient in-plate preparation of serial dilutions using a multichannel pipet. Concentrations are in µM.
Açıklamalar
The authors have nothing to disclose.
Materials
Mueller-Hinton Medium
Oxoid
CM0405
Follow recommendations of manufacturer
RPMI-medium
Corning
17-105-CV
CRPMI
Ref 9
RPMI-1640 medium chelexed for 1 hr with Chelex 100 resin and then supplemented with 10% unchelexed RPMI-1640
Chelex 100 Resin
Bio Rad
142-2822
MBEC-plates
Innovotech
19111
Resazurin Sodium Salt
Sigma
R7017
800 µg/ml in DI water Filter sterile
Micro Plate Shaking Platform
Heidolph Titramax 1000
Cytation 3 Plate Reader
Biotek
Gen5 software
Biotek
Recording and analysis of resazurin conversion
Neocuproine
Sigma
N1501
Prepare 10 mM stock in 100% Ethanol, store at -80 ºC
Copper sulfate
Acros Organics
7758-99-8
Prepare a 100 mM stock solution in water, store at 4 ºC
Cu-Neocuproine
Self-Made
Generated by mixing equal molarities of neocuproine and copper sulfate. Mix was diluted in CRPMI medium to desired concentration.