Search results
Results from the WOW.Com Content Network
Agar dilution is one of two methods (along with broth dilution) used by researchers to determine the minimum inhibitory concentration (MIC) of antibiotics. It is the dilution method most frequently used to test the effectiveness of new antibiotics when a few antibiotics are tested against a large panel of different bacteria.
To calculate the transformation efficiency, divide the number of colonies by the number of cells plated and multiply by 100. The result will be the transformation efficiency as a percentage. For example, if you plate 1x 10 7 cells and count 1000 colonies, the transformation efficiency is: (1000/1x 10 7) x 100 = 0.1%
Negative selection through replica plating to screen for ampicillin sensitive colonies. Replica plating is a microbiological technique in which one or more secondary Petri plates containing different solid (agar-based) selective growth media (lacking nutrients or containing chemical growth inhibitors such as antibiotics) are inoculated with the same colonies of microorganisms from a primary ...
Blood agar plates (BAPs) contain mammalian blood (usually sheep or horse), typically at a 5–10% concentration. BAPs are enriched, and differential media is used to isolate fastidious organisms and detect hemolytic activity. β-Hemolytic activity will show lysis and complete digestion of red blood cell contents surrounding a colony.
The CFU/plate is read from a plate in the linear range, and then the CFU/g (or CFU/mL) of the original is deduced mathematically, factoring in the amount plated and its dilution factor. A solution of bacteria at an unknown concentration is often serially diluted in order to obtain at least one plate with a countable number of bacteria.
The plates are left upright on the bench to dry before inversion and incubation at 37 °C for 18 – 24 hours (or appropriate incubation conditions considering the organism and agar used). Each sector is observed for growth, high concentrations will give a confluent growth over the area of the drop, or a large number of small/merged colonies.
But rookie DC Zach Orr has his unit on track, in large part thanks to multi-talented S Kyle Hamilton exerting his various talents of late and a pass rush being led by veteran LB Kyle Van Noy.
Plate 1:10 and 1:100 dilutions of the incubated cultures on selective/ screening plates (e.g. Ampicillin and/or X-gal) onto LB plates to which the antibiotics to be used for selection have been added; Incubate overnight at 37°C; Finally, observe isolated colonies on the plates